IntroductionAccurate prediction of maize (Zea mays L.) grain yield is critical for efficient resource management and enhancing productivity in sustainable agriculture, particularly in low-input systems. The integration of biofertilizers, such as plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF), offers a promising avenue to improve crop performance while reducing environmental impacts. However, the complexity of ecophysiological data and their interactions necessitates advanced modeling techniques for precise yield prediction. Machine learning (ML) algorithms, combined with optimization methods, provide robust tools to address this challenge (Ingole et al., 2025). This study proposes a novel hybrid approach combining the Non-dominated Sorting Genetic Algorithm II (NSGA-II) for feature selection and the eXtreme Gradient Boosting (XGBoost) algorithm for predictive modeling. By leveraging ecophysiological data, this approach aims to optimize maize yield predictions under biofertilizer applications, supporting precision agriculture and climate adaptation strategies. The objectives were to identify key predictive features, enhance model accuracy, and interpret the contributions of selected variables to yield outcomes. Materials and MethodsThe study utilized data from 96 experimental plots at the Ferdowsi University of Mashhad's research fields, collected over two years. A comprehensive dataset comprising 75 features (32 primary and 43 interaction terms) was compiled, including ecophysiological variables such as chlorophyll content index (SPAD), canopy temperature, maximum photosynthesis rate, specific root length, and soil phosphorus percentage. The methodology consisted of two main phases: feature selection and predictive modeling. First, NSGA-II, a multi-objective optimization algorithm, was employed to select an optimal subset of features by simultaneously maximizing prediction accuracy (coefficient of determination, R²) and minimizing the number of features. NSGA-II iteratively evaluated feature combinations to identify a Pareto-optimal set, balancing model simplicity and performance. Subsequently, the selected features were used to train an XGBoost model, a gradient-boosting framework known for its robustness in handling complex datasets. The model was validated using 5-fold cross-validation to ensure generalizability. Model interpretability was enhanced through SHapley Additive exPlanations (SHAP) and Local Interpretable Model-agnostic Explanations (LIME) methods. SHAP analysis provided global and local feature importance, while LIME elucidated individual prediction contributions. Counterfactual analysis was also conducted to assess the impact of removing key features on model predictions. Results and DiscussionNSGA-II successfully identified nine key features critical for yield prediction, including canopy temperature at the dough stage (Canopy Temp_4), chlorophyll content index at the milk stage (SPAD_3), soil respiration rate, and maximum photosynthesis rate. These features were selected for their ability to maximize R² while maintaining model parsimony. The trained XGBoost model achieved an R² of 0.63 and a root mean square error (RMSE) of 2.171 tons per hectare, indicating moderate predictive accuracy suitable for agricultural applications. SHAP analysis revealed that SPAD_3 (mean SHAP value: 0.2603 t/ha) and Canopy Temp_4 (0.2512 t/ha) were the most influential predictors, positively contributing to yield predictions. Conversely, complex interactions, such as the interaction between leaf area index at the silking stage and the squared mean canopy temperature, had a slight negative effect (-0.0674 t/ha). LIME analysis further highlighted the negative influence of ear length (weight: -0.9252), suggesting its role in reducing predicted yields in specific cases. The Pareto front generated by NSGA-II corroborated the trade-off between feature count and prediction accuracy, while feature importance plots aligned with SHAP and LIME findings. Counterfactual analysis demonstrated that excluding key features significantly altered predictions, underscoring their importance. The integration of NSGA-II and XGBoost proved highly effective in optimizing maize yield predictions under biofertilizer influence, offering a robust framework for low-input agriculture. The selection of nine key features by NSGA-II reduced model complexity while maintaining predictive power, aligning with the principles of precision agriculture. The high influence of SPAD_3 and Canopy Temp_4 underscores the importance of physiological and environmental factors in yield determination, particularly in biofertilizer-enhanced systems. The negative contribution of certain interaction terms and ear length suggests the need for careful consideration of variable interactions in model development. The use of SHAP and LIME enhanced model transparency, providing actionable insights for farmers and researchers. Compared to traditional models, this hybrid approach outperformed baseline methods, achieving a higher R² and lower RMSE. The findings support the adoption of advanced ML techniques in sustainable agriculture, enabling precise resource allocation and adaptation to climatic variability. Future research could explore additional biofertilizer types and larger datasets to further refine predictive accuracy and generalizability. ConclusionIn conclusion, this study successfully developed and validated a hybrid modeling framework integrating NSGA-II for multi-objective feature selection with XGBoost for predictive modeling, enabling accurate maize grain yield prediction under biofertilizer applications in low-input systems. By identifying a parsimonious set of nine key ecophysiological features—most notably chlorophyll content index at the milk stage (SPAD_3) and canopy temperature at the dough stage—the approach achieved a respectable R² of 0.63 and RMSE of 2.171 t/ha, demonstrating moderate yet practical predictive power suitable for precision agriculture in variable environments. Interpretability analyses via SHAP and LIME underscored the dominant positive contributions of physiological indicators while highlighting nuanced negative effects from certain interactions and traits like ear length, providing valuable insights into biofertilizer-mediated yield dynamics. This methodology not only outperformed traditional baselines by balancing model complexity and accuracy but also supports sustainable resource management and climate-resilient strategies in arid and semi-arid regions. Future efforts should expand datasets, incorporate diverse biofertilizer regimes, and test generalizability across broader agroecological zones to further enhance predictive robustness and real-world applicability.
IntroductionWheat (Triticum aestivum L.) is a strategic global crop, vital for food security, providing approximately 20-25% of the world's caloric intake and a significant share of dietary protein. With the global population projected to reach 9.6 billion by 2050, the implementation of sustainable agricultural practices has become imperative to meet escalating food demands without exacerbating environmental degradation. Traditional farming, heavily reliant on chemical fertilizers and pesticides, has led to soil and water pollution, threatening ecosystem health and human safety. In this context, soil microorganisms, particularly arbuscular mycorrhizal fungi (AMF), play a pivotal role in sustainable production by enhancing nutrient cycling and improving the bioavailability of essential elements like nitrogen and phosphorus. Nitrogen is a major yield-limiting factor in wheat production, with peak demand during tillering, heading, and grain filling stages. However, conventional nitrogen sources like urea are prone to leaching in light soils, contaminating groundwater. Bio-fertilizers and plant growth-promoting rhizobacteria (PGPR) offer a sustainable and eco-friendly alternative to chemical fertilizers, improving both targeted plant nutrition and soil physicochemical properties. Furthermore, plant hormones, such as cytokinins, act as chemical messengers and are crucial in mediating plant responses to environmental stresses. Cytokinins regulate key processes including cell division, chlorophyll synthesis, delay of senescence, and ultimately, yield enhancement. The Pishgam wheat cultivar, developed for cultivation under normal and limited irrigation in Iran's cold climates, has shown promising performance. However, limited information exists on its response to co-application of mycorrhizal fungi and cytokinin hormones. Therefore, this study was conducted to investigate the effects of different inoculation levels of mycorrhizal fungi, urea fertilizer, and cytokinin foliar application on the yield and yield components of irrigated Pishgam wheat. Materials and MethodsThe experiment was carried out during the 2022-2023 cropping season at the research farm of Islamic Azad University, Mahabad Branch, West Azerbaijan, Iran. The study was arranged as a factorial experiment based on a Randomized Complete Block Design (RCBD) with three replications. The experimental factors included: first, mycorrhizal organic fertilizer (containing mycorrhizal fungi) at three levels (2, 4, and 6 kg per 100 kg of seed); second, urea fertilizer from a urea source at three levels (0, 50, and 100 kg per hectare); and third, cytokinin foliar application (6-benzylaminopurine) at three stages (no application, application at flowering stage—Zadoks code 55, and application at the beginning of grain filling stage). The seeds of the Pishgam cultivar were disinfected with 70% ethanol and sodium hypochlorite before being inoculated based on the treatment groups. Soil analysis indicated a loamy clay texture with neutral to weak alkaline pH, negligible urea, and sufficient levels of phosphorus and potassium. Seeds were planted at a depth of 4 cm with a density of 180 kg.ha-1. Urea fertilizer was applied in two splits: one-third at planting and the remaining two-thirds at the beginning of stem elongation and before flowering. A 3 mM cytokinin solution was prepared and applied at a rate of 1.5 liters per plot using a hand sprayer, with Tween 20 added as a surfactant. Standard weed, pest, and disease management practices were uniformly applied. At physiological maturity, plants from a one-square-meter area per plot were harvested. Measured traits included plant height, flag leaf length, spike length, number of fertile spikes per square meter, number of grains per spike, thousand-kernel weight, biological yield, grain yield, and harvest index. Data were subjected to analysis of variance (ANOVA) using SAS software (version 9.4), and mean comparisons were performed using Duncan's Multiple Range Test at a 5% probability level. Results and DiscussionThe analysis of variance revealed that the interaction effects between the factors were highly significant. The interaction between mycorrhizal fungi and urea fertilizer significantly influenced flag leaf length, spike length, number of spikes per square meter, and biological yield. Similarly, the interaction between mycorrhizal fungi and cytokinin application had a significant effect on plant height, flag leaf length, grain yield, and harvest index. Furthermore, the interaction between urea fertilizer and cytokinin application timing significantly affected spike length, number of spikes per square meter, thousand-kernel weight, grain yield, and harvest index. The highest grain yield (approximately 12 tons.ha-1) was achieved with the combined application of 4 kg.ha-1 mycorrhiza, 50 kg.ha-1 urea, and cytokinin spraying at the flowering stage. This combination outperformed the control and other treatments, highlighting a strong synergistic effect. The results demonstrated that mycorrhizal inoculation, particularly at 4 kg.ha-1, significantly enhanced nutrient uptake, especially phosphorus, leading to improved photosynthetic capacity and longer flag leaf duration. Cytokinin application, especially at the flowering and grain filling stages, effectively delayed senescence, increased the number of fertile tillers, and improved grain filling efficiency. The combination of these treatments allowed for a substantial reduction in urea fertilizer input by 50% (from 100 to 50 kg.ha-1) without any compromise in yield, underscoring the role of bio-fertilizers and growth regulators in enhancing nutrient use efficiency. The improvement in yield components, including spike length, number of spikes per unit area, and thousand-kernel weight, was directly linked to better resource allocation and reduced oxidative stress under the integrated management approach. ConclusionThe findings of this research conclusively show that the integrated application of mycorrhizal fungi (at an optimal rate of 4 kg.ha-1), reduced urea fertilizer (50 kg.ha-1), and cytokinin foliar spraying at critical reproductive stages (flowering and early grain filling) can significantly enhance the yield and yield components of Pishgam wheat. This management strategy works through multiple mechanisms: improved nutrient and water uptake via expanded root systems mediated by mycorrhizae, enhanced photosynthetic activity and delayed leaf senescence induced by cytokinins, and more efficient allocation of photo-assimilates to the grains. The study successfully demonstrates that it is possible to replace a significant portion of chemical urea fertilizer with organic amendments and growth regulators, thereby promoting a more sustainable and environmentally friendly wheat production system without sacrificing productivity. For achieving high and stable yields in wheat cultivation under similar agro-climatic conditions, it is highly recommended to adopt this integrated approach using 4 kg.ha-1 mycorrhizal seed inoculation, 50 kg/ha urea application, and cytokinin foliar spray at the flowering stage. AcknowledgementThe authors of this article feel it necessary to sincerely express their gratitude for the cooperation and support of the officials of the Faculty of Agriculture and the laboratory experts at Islamic Azad University, Mahabad Branch, who extended their utmost assistance during various stages of this research.
IntroductionThis temperature varies for each species, but there is a linear relationship between growing degree-days and plant growth rate. Growing degree-days (GDD) are used to classify plants by their flowering date, to estimate harvest maturity, and to predict the length of time between two growth stages. In a study in Ardabil, the findings indicated that the temperature of the region is correlated with the temperature of corn growth, and based on the zoning, about 16% of the total area of the province was identified as very suitable, 22% as suitable, 27% as moderate, and about 35% as unsuitable for corn cultivation. The aim of this study is to zone GDD and identify ranges of cumulative growth degree days, which can be used to more accurately determine the amount of crop cultivation and their production management in different counties of Isfahan province. Materials and MethodsIn this study, 30-year daily temperature statistics (minimum, maximum, and average) from 33 meteorological stations were used to calculate GDD and growing season length (1984 to 2021). To calculate thermal units, the first growing season length for temperature thresholds of 5°C and 10°C was extracted using the Jillosy coding method (March 3rd with code 1 and March 2nd with code 365), and then the growing season thermal units were calculated by subtracting the average daily temperature from the base temperature. Finally, zoning maps were drawn for each indicator in Arc GIS. Despite different definitions of the growing season, temperature and humidity play a special role in all of these definitions. According to the definition of the World Meteorological Organization's Commission on Climatology/Climate Variability, the length of the growing season is the time interval between the first period after July 10th in which the average daily temperature is above 5°C for at least 6 consecutive days (as the starting point) and the first 6-day period with an average daily temperature below 5°C (as the ending point). Results and DiscussionThe cities of Isfahan province were divided into 4 groups based on a base temperature of 5°C, which received a range of 2500 to 5000-degree days of temperature growth. This number changed from 1500 to 4500 degrees Celsius for a base temperature of 10°C. Based on a base temperature of 5°C, the shortest growing season length of 114-200 days was observed in the western and southern regions of the province, and the longest growing season length of 365-331 days was observed in the northern and eastern regions of Isfahan province. For a base temperature of 10°C, a similar geographical trend was observed, with the difference that the range of the shortest and longest growing season lengths was (72-140) and (306-261) days, respectively. The correlation coefficient between GDD at base temperatures of 5 and 10°C and longitude was significant at the 95% level. The relationship between the temperature units received during the growing season and the longitude at the base temperature of 5 and 10 °C was increasing from west to east of Isfahan province. ConclusionThe results showed that in Isfahan province, the length of the growing season and the absorbed GDD increase as one move from west to east. Moving from north to south of the province was an inverse relationship. Based on the base temperature of 5°C, the shortest growing season length is 114-200 days in the western and southern regions of the province and the longest growing season length is 331-365 days in the northern and eastern regions of Isfahan province. For the base temperature of 10°C, a similar geographical trend is observed, with the difference that the range of the shortest and longest growing season lengths is (72-140) and (306-261) days, respectively. Considering the base temperatures of 5°C and 10°C, the cities of Isfahan province are classified in the range of 1500 to more than 5000 GDD. The help of this classification, it is possible to predict the time of occurrence of weeds and pests in different regions. Certainly, by combining temperature zoning with other elements required by each plant (soil, topography and precipitation), more comprehensive information will be obtained.
IntroductionSesame (Sesamum indicum L.) is a key oilseed crop, prized for its high-quality oil and protein content, making it vital to both agriculture and the economy. As global population growth drives up demand for vegetable oils, sesame production has become increasingly significant in Iran and worldwide. However, the heavy reliance on chemical fertilizers to enhance yields has caused environmental challenges, including soil degradation, reduced fertility, and water pollution. Biochar, a stable organic material produced through the thermal decomposition of plant biomass, offers a sustainable alternative by improving soil’s physical and chemical properties, enhancing water retention, and reducing nutrient loss. Combining biochar with chemical fertilizers can decrease dependency on chemical inputs while boosting crop performance, supporting sustainable farming practices. This study evaluated the effects of integrated biochar and chemical fertilizer application on sesame’s morphophysiological and agronomic traits, aiming to develop a practical strategy for improving its productivity. Materials and MethodsThis study was conducted during the 2020-2021 cropping season as a factorial experiment in a randomized complete block design with three replications in a field located in Aliabad-e Katul, Golestan Province, Iran. The experiment evaluated five biochar levels (0, 2, 4, 8, and 10 by weight, denoted as B0, B2, B4, B8 and B10) and three chemical fertilizer levels (0, 50%, and 100% of crop requirement, denoted as F0, F50%, and F100%). Soil samples from a 0-30 cm depth were analyzed for physicochemical properties before land preparation, which involved plowing, disking, and leveling. Nitrogen, phosphorus, and potassium fertilizers were applied based on soil test results, with urea, triple superphosphate, and potassium sulfate as sources. The cultivar Oltan was planted manually on June 15, 2020, in 4×5 m plots. Irrigation occurred weekly, and weed, pest, and disease control were maintained. Harvesting took place on October 12, 2020, with traits such as plant height, number of lateral branches, number of capsules per plant, number of seeds per capsule, 1000-seed weight, seed yield, biological yield, harvest index, Oil percentage, Oil yield and chlorophyll content (a, b, and total) measured. Chlorophyll was quantified using spectrophotometry at 663, 646, and 470 nm wavelengths. Results and DiscussionThe results indicated that all examined traits were significantly influenced by the main effects of biochar and chemical fertilizer. The interaction effect was significant only for the number of capsules per plant. The highest plant height (102.57 cm), number of lateral branches (4.03), number of capsules per plant (54.11), thousand seed weight (2.97 g), seed yield (1267.4 kg.ha-1), biological yield (5418.3 kg.ha-1), harvest index (22.03%), Oil yield (625.22 kg.ha-1) and chlorophyll a (1.62 mg.g-1 fresh weight) were obtained from the treatment with B8 biochar and F100% chemical fertilizer. The highest number of seeds per capsule (70.59) was recorded in the B10 biochar treatment. The highest levels of chlorophyll b and total chlorophyll were observed in the B4 biochar treatment, with 1.15 and 2.75 mg.g-1 fresh weight, respectively. The control treatment recorded the highest oil percentage of 52.82%. Biochar improved soil water and nutrient retention and enhanced the uptake of nutrients such as nitrogen and magnesium, while chemical fertilizers provided direct access to nutrients and promoted growth. These results are consistent with previous research that emphasizes biochar’s role in increasing crop yield and quality. The synergy between biochar’s soil-improving effects (such as increased cation exchange capacity) and the nutrient supply from chemical fertilizers significantly enhanced sesame performance. Since the highest seed yield was obtained at the highest fertilizer level used, further research is recommended to determine the optimal fertilizer level. ConclusionThe use of biochar and chemical fertilizers markedly enhanced sesame’s morphophysiological and agronomic responses. Biochar improved soil conditions and minimized nutrient leaching, while chemical fertilizers supplied essential nutrients, resulting in higher seed yields and better growth metrics. This approach demonstrates potential for reducing chemical fertilizer use and advancing sustainable agriculture. Future studies should explore optimal application rates and long-term impacts.
Introduction[1]The escalating demand for food, driven by global population growth, poses a significant threat to environmental sustainability. Conventional monoculture agricultural systems, while often profitable in the short term, are increasingly recognized as major contributors to soil degradation, biodiversity loss, and heightened vulnerability to climate change and economic fluctuations. In response, integrated agricultural systems, such as agroforestry, which synergistically combine crops, livestock, poultry, and trees, have emerged as a promising pathway toward sustainable intensification. These systems are theorized to enhance ecological resilience through increased biodiversity, improve soil health, and offer greater economic stability by diversifying income sources and reducing dependency on external inputs. This study was therefore designed to conduct a comprehensive evaluation of sustainability and economic productivity indicators, comparing mono-dimensional and integrated agricultural systems in two distinct villages within Meshginshahr County, Iran, with a specific focus on ecological health, economic viability, and the critical metric of local food security. Materials and MethodsThis survey-analytical research was conducted in 2023 in two purposively selected villages—Arjaq and Jabdaraq—located in Meshginshahr County, Ardabil Province, Iran. Data collection integrated field observations, in-person interviews with local farmers, and official agricultural census data. To quantitatively assess sustainability, a novel Composite Agricultural Diversity Index (ADI) was constructed, comprising five weighted components: Biodiversity (Shannon-Wiener Index), Functional Diversity, Spatial Diversity, Temporal Diversity, and Resilience (assessed through farmer surveys on system recovery from disturbances). Economic analysis was performed by calculating total costs, income, profit, and profit percentage for each documented agricultural system. Food self-sufficiency was evaluated by comparing the annual production of key food groups within each village against established per capita consumption requirements. Additionally, new indices for land-based and population-based self-sufficiency were developed and calculated to provide a holistic view of local food security. Results and DiscussionThe findings revealed a pronounced superiority of integrated agricultural systems across all evaluated metrics. Ecologically, the most complex system (Arable + Gardening + Livestock + Poultry) achieved the highest Composite Agricultural Diversity Index in both Arjaq (4.718) and Jabdaraq (4.181), far exceeding scores for single-activity systems like sole gardening (1.170) or livestock (0.865). This high ADI signifies greater biodiversity, functional redundancy, and spatial complexity, which directly contribute to enhanced ecosystem resilience against environmental stresses such as pests and drought. Soil quality analysis corroborated these findings, showing superior organic matter content and nutrient levels (e.g., nitrogen, phosphorus) in systems incorporating trees and diverse plant cover compared to monoculture arable lands. Economically, the integrated systems demonstrated robust performance. While individual components like poultry sometimes showed high profit percentages, the combined systems (e.g., Arable+Gardening+Livestock) generated significantly higher total absolute profits (e.g., 270.97 million Rials in Arjaq) due to synergistic effects. These synergies included using livestock manure as organic fertilizer, thereby reducing costs for chemical inputs, and utilizing crop residues as animal feed. This resource recycling not only lowered operational expenses but also distributed economic risk across multiple revenue streams, insulating farmers from market or crop-specific failures. The most striking outcome was the disparity in food self-sufficiency. Jabdaraq, with its highly diversified production, achieved complete self-sufficiency, producing surpluses in crucial categories like poultry meat (175% of need), cereals (187%), and garden products (a remarkable 1714%). In stark contrast, Arjaq, despite its focus on lucrative grape production and greater access to irrigation, exhibited significant deficits in animal protein, meeting only 38% of its poultry, 44% of its egg, and 0% of its fish requirements. Its massive surplus in garden products (1589%) was insufficient to compensate for these core nutritional shortfalls, highlighting the risks of over-specialization. Consequently, the composite self-sufficiency index for Jabdaraq (5.08) was more than double that of Arjaq (2.3), underscoring that diversification, rather than mere land or water availability, is the cornerstone of sustainable food security. ConclusionIn general, multi-dimensional, integrated agricultural systems deliver enhanced ecological sustainability through greater biodiversity and soil health, improved economic profitability and risk mitigation through synergistic resource use, and, most importantly, ensure genuine local food self-sufficiency. the presence of diverse agricultural systems in an area leads to increased economic sustainability and food security, and to some extent compensates for limited access to water. It also reduces the need for external and chemical inputs, which results in greater economic and environmental productivity.
IntroductionGlobal food demand is rising, and by 2050 the world population is expected to reach about 9 billion. To meet this demand under increasing environmental pressures, improving the efficiency of production factors through sustainable agricultural practices is essential. Conventional tillage and sole-cropping systems often suffer from limited ground cover and associated soil degradation. Intercropping systems, especially mixtures of cereals and legumes, can enhance resource use efficiency, improve soil quality via biological nitrogen fixation, and reduce soil erosion while maintaining or increasing forage yield and quality. This study focuses on the performance of intercropping two forage crops, vetch (Vicia sativa L.) and triticale (×Triticosecale Wittmack), under different tillage regimes, aiming to identify combinations that optimize forage quality under dryland conditions in Kurdistan, Iran. Materials and MethodsThe field experiment was conducted during the 2019–2020 growing season at the Kurdistan University experimental farm. The trial employed a split-plot based on a randomized complete block design with three replicates. The main plots consisted of three tillage treatments: conventional tillage (plough-back, disc, and harrow), reduced tillage (chisels), and no-tillage. Subplots represented six sowing patterns: (I1v) pure vetch, (I1t) pure triticale, (I2) 80% triticale+20% vetch, (I3) 60% triticale+40% vetch, (I4) 40% triticale+60% vetch, and (I5) 20% triticale+80% vetch. Subplot dimensions and spacings were standardized, with three 5 m by 1.5 m main plots per replicate. Quality parameters of the forage were assessed at anthesis by harvesting excluding edge effects. The laboratory analyses included crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and ash content, following standard procedures. Plant height and dry matter (DM) yield were also recorded. Data were analyzed using SAS 9.1. Means were compared with LSD at 5% probability. Figures were produced in Excel. Results and Discussion Analysis of variance showed significant interactions between tillage and intercropping on several forage quality traits in both species. Specifically, the interaction affected the acid detergent fiber (ADF) and crude protein (CP) of vetch forage at the 1% level, and also influenced the neutral detergent fiber (NDF) and CP of vetch and triticale in different contexts. Overall, ADF and ash contents, and CP of vetch, were sensitive to tillage × intercropping, whereas NDF showed pronounced responses to tillage and intercropping independently in many treatment combinations. Crude protein was higher in vetch pure stands and generally increased under no-tillage compared with conventional tillage. In the intercropping setups, CP of triticale tended to rise as vetch proportion increased, indicating a positive effect of legume association on the protein content of the cereal component, likely due to better nitrogen availability and improved canopy light capture under mixed stands. The content of ADF (and thus digestibility potential) and NDF was notably affected by tillage and intercropping. Pure cropping with conventional tillage tended to exhibit higher NDF and ADF values compared with no-till and mixed stands, suggesting lower forage digestibility in traditional systems. Intercropping, especially with favorable cereal-legume ratios, reduced fiber concentrations in some treatments, aligning with improved forage quality reported in other cereal-legume mixtures. Ash content was mainly driven by intercropping. Among the treatments, pure vetch exhibited the highest ash content, while pure triticale had the lowest, with mixed patterns showing intermediate values. This pattern reflects changes in mineral content and tissue composition influenced by species mix and resource availability. Dry matter did not show significant differences among tillage systems in this study. The land equivalent ratio (LER) analysis demonstrated that intercropping, particularly at ratios of triticale 80% + vetch 20% improved LER across all tillage treatments, with the highest LER observed under conservation tillage systems. ConclusionThe study demonstrates that tillage systems and intercropping patterns significantly influence the quality of forage from vetch and triticale under dry Mediterranean conditions. Intercropping, particularly with balanced cereal–legume ratios, improved forage quality by modulating Crude Protein and fiber fractions (Acid Detergent Fiber and Natural Detergent Fiber), and reduced ash content relative to pure stands under some tillage regimes. No-tillage tended to enhance CP for vetch, and under intercropping, CP of the cereal component increased, suggesting improved nitrogen use efficiency and forage nutritive value in conservative farming systems. Intercropping, especially at an 80:20 ratio, improved LER, particularly under conservation tillage systems. Practically, adopting conservation or reduced tillage in combination with carefully designed vetch–triticale mixtures can enhance forage quality and soil health in semi-arid environments.
IntroductionWheat (Triticum aestivum L) is one of the most important cereal crops. A model is a tool that helps us interpret and understand the world we live in. Crop modeling, a branch of agricultural science, has been around for about 40 years, with the development of powerful and efficient computers playing a major role in its advancement. These models usually enable the determination of management options and can be used to explore a wide range of management strategies at low costs. Plant models have proven to be useful tools for estimating crop yield, integrating a comprehensive set of values under physiological conditions, and evaluating crop management options. One essential feature of simulation models is the accurate prediction of crop phenology. The key phenological stages required for simulating the physiological processes of growth and yield in wheat are as follows: Days from planting to emergence, days from emergence to tillering, days from tillering to stem elongation, days from stem elongation to booting, days from booting to heading, days from heading to anthesis, days from anthesis to physiological maturity, and days from physiological maturity to harvest. The aim of this research is to evaluate the SSM-Wheat model for predicting the phenological stages and yield of wheat. Materials and MethodsThe necessary information for simulating the phenological stages and yield of wheat was obtained from experimental data on 7 planting dates (November 1st, November 10th, November 20th, November 30th, December 10th, December 20th, and December 30th) and four bread wheat genotypes (line N9-93 and the varieties Araz, Taktaz, and Arman) over two cropping years, 2019-2020 and 2020-2021. Data on the phenological stages and yield of wheat were used to evaluate the model. Daily meteorological data (maximum and minimum temperatures, precipitation, and solar radiation) were collected and defined in the model. Soil characteristics parameters were considered based on the model's default data. Results and DiscussionThe evaluation of the SSM-Wheat model showed that this model accurately simulates the phenological stages, including days to emergence, days to stem elongation, days to heading, days to flowering, and days to physiological maturity, as well as grain yield across different planting dates and wheat varieties under the climatic conditions of Gonbad. However, the model did not accurately predict days to tillering, biological yield, and harvest index. The highest coefficients of determination (R²) were obtained for days to heading (0.79), days to flowering (0.77), and days to physiological maturity (0.92). Accurate prediction of crop phenology is a crucial feature of simulation models. Yield in crop simulation models is largely regulated by the timing of developmental stages. The poor prediction of biological yield and harvest index may be due to water stress and high temperatures during the grain-filling and maturity stages, which caused leaf drop and reduced biomass, leading to incomplete harvest by the combine. Delayed planting and low temperatures during the early growth stages in areas with very cold winters, due to inadequate plant establishment and growth to withstand autumn frosts, and high temperatures in hot and dry regions during the late growth stages, especially the grain-filling period, can reduce plant yield. Grain weight is a key component of final grain yield and is influenced by environmental stresses, particularly water stress. ConclusionThe evaluation of the SSM-Wheat model showed that this model was acceptable in simulating phenological stages, including days to emergence, days to stem elongation, days to heading, days to flowering, days to physiological maturity, and grain yield across different planting dates and cultivars under the climatic conditions of Gonbad Kavous. However, the model poorly predicted days to tillering, biological yield, and harvest index. It seems necessary to revalidate and refine the model accuracy using data from diverse experiments, and if the results of this review are confirmed, to incorporate them into the model equations. Nevertheless, this model can be used in field management planning, such as selecting planting dates, suitable cultivars, analyzing crop yield, and its limitations. Obviously, models become effective only when applied with an analysis of physiological and ecological conditions, based on experimental measurements and observations from the system. © Authors retain the copyright. This is an open access article distributed under Creative Commons Attribution 4.0 International License (CC BY 4.0)
IntroductionCompetition between wheat (Triticum aestivum L.) and weeds is one of the most important restrictions of global production of this plant, and Human solutions for management of pests and weeds have destroyed the biodiversity in agroecosystems (Bushong et al., 2011; Lemerle et al., 2001). The function of natural and agricultural ecosystems is based on biodiversity. Destruction of biodiversity is a serious threat to the sustainability of agricultural ecosystems and, ultimately, food security in the world. Use of pesticides and chemical fertilizers is one of the most important methods of intensive management in agriculture that damages biodiversity (Marshal et al., 2003). Materials and MethodsA factorial experiment based on a randomized complete block design with three replications in two years of 2012-13 and 2013-14. The test factors included pesticides at three levels (Non insecticide, Deltamethrin as a general insecticide and Phyenrythion as a specific insecticide) and Herbicide on four levels (Non herbicide, two herbicides 2,4.D , Topic and the combination of them) was carried out. Weeds were sampled 5 times during the growing season, and Weed species were identified and counted. Sampling was performed before and after the treatment. Relative density and relative frequency of weeds, weed Species, Shannone diversity index, Species reachness and wheat yield were studied. Results and Discussion Data analysis showed that in both years, the effect of herbicides on the weed density and dry weight of broad-leaf weeds and total weed dry weight were significant. However, the effects of pesticide treatments on the density and dry weight of weeds were not significant. In both crop years, the use of two herbicide mixtures had the greatest effect on reducing the density and dry weight of broadleaved weeds and total weed dry weight. The highest Shanone diversity index was observed in non-herbicide treatments in 2012-13, which had a significant difference with other treatments. The highest Shannon diversity index was observed in the control plots, and the lowest Shannon diversity index were observed in the combined treatments of both herbicides in the 2013-14 crop year. It seems that the combination of both herbicides, in addition to dry weight and density, has the greatest impact on weed species diversity. The species observed in both years were similar to each other. The main weed species of the field included Convolvulus arvensis L.، Descurainia sophia Webb ex Prantl ، Avena ludoviciana Durieu, and Secale cereale L. The contribution of grass species to the total density was 30% and the share of broad-leaf weed was measured at 70%. Therefore, the frequency of broadleaved species was higher than that of grass weeds in the field. Herbicides changed the demographic structure of weed societies and reduced the weed biodiversity index. In both years, different treatments of pesticides did not have a significant effect on the changes in weed density. The effect of herbicides in both years and the effect of pesticides only in the 2013-2014 on the yield of wheat were significant. The application of pesticides significantly increased the economic yield of wheat. However, increasing the density and dry weight of the weed decreased wheat economic yield. Wheat economic yield decreased with increase in weed density and weed dry weight. ConclusionHerbicides have changed the population structure of weeds and reduced the biodiversity index of weeds. Negative and significant correlations were observed between wheat yield and species richness and shannon diversity index in both years. In general, Intensive management, specially herbicide usage in wheat agroecosystem, changed the composition of the plant communities and reduced the biodiversity and weed species richness. The result of the reduction in diversity in this ecosystem is a greater dependence on chemical inputs, which causes environmental pollution and a threat to agricultural sustainability.
Introduction Cowpea (Vigna unguiculata L.) is an annual plant from the legume family. This plant is adaptable to different climates and can be cultivated in many regions of Iran. Legumes often experience strong competition from weeds because of their slow early growth rate and limited leaf area development during the initial stages of growth. Weeds reduce nutrient uptake, make mechanized harvesting difficult, and reduce the quality and quantity of grain and straw. Therefore, weed control is a key aspect of agricultural production. Chemical control is not the only solution. The continuous use of herbicides has negative environmental impacts and is not compatible with the goals of sustainable agriculture. Planting arrangements enhance weed competition by altering the structure of the canopy. Mulches reduce water evaporation, improve soil temperature, and reduce competition for water and nutrients. Mulches inhibit weed germination by providing shade, a physical barrier, and the release of allelopathic substances. They also reduce water evaporation, improve soil temperature, and reduce competition for water and nutrients. Mulches suppress weed germination by providing shade, a physical barrier, and the release of allelopathic substances. Despite the great differences in the growth habits of cowpea species, little is known about the effect of these differences on weed competition. Also, the effect of planting arrangement and plant mulch on yield and weed competition has not been investigated. Therefore, this study was conducted to determine the optimum planting arrangement to reduce yield loss and to evaluate the role of mulch in controlling weeds and their competition with cowpea. Materials and MethodsThis study was conducted during the 2021–2022 growing season at Haft Tappeh Sugarcane Cultivation Company in Shush, Iran, to evaluate the effects of planting patterns and non-chemical weed control methods on the uptake efficiency of nitrogen (N), phosphorus (P), and potassium (K) in cowpea (Vigna unguiculata). The experiment was arranged as a factorial based on a randomized complete block design with three replications. The first factor was planting arrangement at three levels: (1) single-row planting with 10 cm spacing, (2) double-row planting with 20 cm spacing, and (3) triple-row planting with 30 cm spacing. The second factor was weed management method at six levels: (1) weed-infested control, (2) hand weeding twice (4 & 8 weeks after emergence), (3) wheat stubble mulch (5 t/ha), (4) wheat stubble mulch + weeding once, (5) sugarcane bagasse mulch (5 t.ha-1), and (6) sugarcane bagasse mulch + weeding once. Each plot consisted of 4 ridges, 75 cm wide and 9 m2 in area. The amount of mulch in each plot was 4.5 kg with an approximate thickness of 5-7 cm. The mulches were distributed after planting and before the first irrigation (24/07/2022). Cowpea (Mashhadi cultivar) was planted on 23/07/2022. Mulches were distributed after the first irrigation, when the soil reached its field capacity, to prevent displacement. Fertilization included 100 kg.ha-1 of phosphorus (triple superphosphate), 100 kg.ha-1 of potassium (potassium sulfate) as a base, and 40 kg/ha of nitrogen (urea) in two applications (4-leaf stage and stem growth, 20 kg.ha-1 each). Weed density and dry weight were measured 4 weeks after the treatments and at the end of the growth period with a 1×1 m2 quadrat. Statistical analysis was performed with SAS version 9.4, and the means were compared with the LSD test at the 5% level (p < 0.05). Results and DiscussionThe results indicated that the interaction of planting arrangement and non-chemical weed control significantly affected nitrogen content in shoots (p < 0.05) and phosphorus content in seeds (p < 0.01). The triple-row planting arrangement exhibited the highest phosphorus content in shoots (0.81%) and seeds (1.4%), attributed to enhanced root expansion and reduced weed competition. The double-row arrangement showed the highest potassium content in shoots (6.1%) and seeds (3.44%), due to reduced intra-species competition. The treatment of sugarcane bagasse mulch + weeding once reduced wet and dry weed biomass significantly at 5% level (wet: 15.6 g.m-²; dry: 3.7 g.m-²). ConclusionThe integrated application of sugarcane bagasse mulch and weeding once effectively decreased weed competition and enhanced nutrient availability, improved cowpea yield. Given the environmental concerns associated with chemical herbicides, these sustainable practices offer promising alternatives for weed management and soil fertility enhancement.
Introduction[1]Garlic (Allium sativum L.) and black seed (Nigella sativa L.) are medicinal plants with diverse applications. Intercropping, a sustainable agricultural practice, can enhance land productivity, reduce pests and diseases, and improve soil fertility. This study aimed to investigate the effects of different intercropping ratios and sowing methods on garlic yield and physiological traits by creating a favourable microclimate. The experiment was conducted in Dezful, Iran, a region with a semi-arid climate, to evaluate how these factors influence garlic growth and productivity. The study focused on optimizing resource use efficiency and understanding the competitive dynamics between garlic and black seed in mixed cropping systems. Materials and MethodsThe study was conducted during the 2021-2022 growing season in Dezful, Iran, at 32°16' N latitude and 48°25' E longitude, with an elevation of 82.9 meters above sea level. The experiment followed a randomized complete block design with three replications. Treatments included combinations of four sowing methods (ridge, furrow, ridge-furrow, and flat planting) and five intercropping ratios (100% black seed, 75% black seed + 25% garlic, 50% black seed + 50% garlic, 25% black seed + 75% garlic, and 100% garlic). The volume of the garlic bulb was measured using a graduated cylinder containing a specific amount of water. By submerging the garlic bulb into the graduated cylinder and recording the increase in the water volume, the volume of the garlic bulb was calculated. Garlic cloves were pre-chilled at 4°C for five days before planting. Black seed was sown at a depth of 1 cm, and garlic at 3.5 cm, with row and plant spacings of 50 cm and 12 cm, respectively. Fertilization included 125 kg.ha-1 of nitrogen (applied in three stages) and 100 kg.ha-1 of phosphorus. Irrigation, weeding, and thinning were performed as needed. Measured traits included leaf area index (LAI), chlorophyll index (SPAD), plant height, leaf dimensions, stem diameter, bulb volume, clove number, bulb weight, and yield. Data were analyzed using SAS software, and means were compared using the LSD test at a 5% significance level. Results and DiscussionThe results revealed significant effects of intercropping ratios and sowing methods on garlic traits. The highest garlic yield (15,003 kg.ha-1) was achieved in sole garlic cultivation with the ridge-furrow method (GRF100), followed by flat planting (GP100) and furrow planting (GF100). Mixed cropping with higher black seed ratios (75%) significantly reduced garlic yield, indicating intense interspecies competition.Leaf Area Index (LAI): The highest LAI (0.200) was observed in the treatment with 75% black seed in furrows and 25% garlic on ridges (BF75+GR25), while the lowest LAI (0.023) occurred in the 25% black seed + 75% garlic ratio on ridges (BR25+GR75). • Chlorophyll Index (SPAD): The highest SPAD value (61.4) was recorded for black seed on ridges and garlic in furrows (BR75+GF25), suggesting better light and nutrient conditions in this arrangement.Bulb Traits: The highest bulb weight (66.7 g) and volume (101 cm³) were observed in sole garlic under flat planting (GP100). Intercropping, especially with high black seed ratios, negatively affected bulb traits.The highest stem diameter of garlic was observed in flat planting of garlic (GP100), while most of the ridge planting treatments showed smaller stem diameters.Yield: The ridge-furrow method (GRF100) outperformed other treatments, likely due to improved soil aeration and reduced competition. Mixed cropping at a 50:50 ratio with black seed on ridges and garlic in furrows (BR50+GF50) showed the lowest competition index (0.50) and the highest land equivalent ratio (1.20), indicating efficient resource use.The lowest competition index and the highest land equivalent ratio (LER) were observed when black seed was planted on ridges and garlic in furrows, with an equal plant ratio (50%-50%). ConclusionsThe study demonstrated that sole garlic cultivation, particularly in ridge-furrow or flat planting systems, maximizes yield and bulb quality. However, intercropping garlic with black seed at a 50:50 ratio, with black seed on ridges and garlic in furrows (BR50+GF50), offers a sustainable alternative by balancing yield and resource efficiency. This arrangement minimized competition and optimized land use, making it suitable for farmers seeking diversified and economically viable cropping systems. Future research should explore nutrient management and irrigation strategies to further enhance the productivity of intercropping systems.
IntroductionSugar beet is the main source of sugar production in Iran, accounting for approximately 60% of the country's sugar production comes. The rest comes from sugar cane (Ribeiro et al., 2016). Hamedan province, with a cultivated area of about 7 percent of the total cultivated area of the country, is one of the most important provinces in terms of sugar beet cultivation and sugar production. Nahavand and Asadabad regions also have the largest cultivated area of sugar beet in Hamedan Province and are considered the most important sugar beet cultivation areas in the province. Seed is a crucial agricultural input. It provides farmers with significant added value by improving the efficiency of other inputs, such as water, fertilizer, pesticides, and machinery. Maximizing yield is impossible without using the right seeds, even with significant energy investment (Sadeghzadeh Hemayati et al., 2024). The primary aim of conducting variety comparison experiments is to select and introduce suitable varieties to farmers in each region, this study was conducted to compare sugar beet varieties and introduce the best variety in the Nahavand and Asadabad regions of Hamedan province. Materials and MethodsTo evaluate the root yield and quality characteristics of some breeding commercial sugar beet varieties in Hamedan province, an experiment was conducted in two regions: Asadabad-Vanderabad Village and Nahavand-Gyan Village, in 2023, under farm conditions. The study included five Iranian commercial cultivars—Sina, Nika, Shokofa, Asia, and Dena—as well as a foreign cultivar, Urslina, which served as the control. Planting took place in Nahavand on March 10, 2022, and in Asadabad on April 15, 2023. A total of 30 planting lines, each measuring 300 meters in length and spaced 50 centimeters apart, were allocated for each cultivar. Each cultivar was planted in an area of 4,500 square meters. The farmer carried out all land preparation and farm management operations in accordance with local customs. At the end of the growing season, four samples (as four replicates) of each variety were randomly harvested and weighed, and root yield was obtained. The harvested roots were washed, pulped, and sent to the Sugar Technology Laboratory at the Sugar Beet Seed Institute for quality characteristic measurement. Cluster analysis and factor analysis were performed using R v.4.2.2 software. Results and DiscussionBecause of the significant interaction effect between cultivar and environment, which indicated independent responses of cultivars in the two different locations, all data analyses were performed separately for each site. In Nahavand, the highest sugar content and white sugar content were observed with 18.24 and 15.87 percent, respectively, and the highest sugar yield and white sugar yield were observed with 19.29 and 16.79 ton.ha-1, respectively, in the foreign cultivar Urslina. Among the Iranian cultivars, the two cultivars Dena and Asia had the highest yield. In Asadabad, results showed that the foreign cultivar Urslina had the highest values among the studied cultivars in terms of sugar content (18.29%), sugar yield (19.80 ton.ha-1), white sugar content (16.17%), white sugar yield (17.51 ton.ha-1), and sugar extraction coefficient (88.4%). Cluster analysis results indicated that the cultivars were grouped into three clusters in Nahavand and four clusters in Asadabad. Based on the results of the cluster analysis conducted in the Nahavand environment, two clusters were introduced as superior clusters. The first cluster included the Urslina variety, while the second cluster comprised the Dena, Asia, and Shokofa varieties. In the Asadabad environment, the first cluster also included the Urslina variety, and the fourth cluster contained the Nika variety, both of which were recognized as superior clusters. Factor analysis identified two significant factors, explaining 95.57% of the variation in Nahavand and 95.94% in Asadabad. ConclusionOverall, the Urslina cultivar emerged as the superior cultivar in both environments. Among the Iranian cultivars, the Dena and Asia cultivars were recommended for the Nahavand environment, while the Nika cultivar was suggested for the Asadabad environment due to their better quantitative and qualitative characteristics.
IntroductionPinto bean (Phaseolus vulgaris L. cv. Pinto) is one of the most important legume crops within the Fabaceae family, cultivated extensively in tropical and subtropical regions. Despite its sensitivity to drought, this species plays a crucial role in food security and sustainable agriculture due to its rich composition of high-quality protein, complex carbohydrates, and essential micronutrients. However, drought stress represents a major abiotic constraint that significantly impairs crop performance by reducing stomatal conductance, decreasing chlorophyll content, disrupting photosynthesis, and limiting root and shoot development. To address this challenge, regulated deficit irrigation has emerged as an efficient strategy for optimizing water use while maintaining acceptable yield levels. Moreover, the application of plant growth regulators such as brassinosteroids, bioactive, eco-friendly, and steroidal compounds, has been recognized as a promising approach to enhancing plant tolerance to abiotic stress. These compounds contribute to stress mitigation by enhancing photosynthetic efficiency, stimulating the biosynthesis of vital metabolites, and activating enzymatic defence systems, thereby supporting plant growth and yield under water-limited conditions. Numerous studies have demonstrated that foliar application of brassinolide, particularly during sensitive developmental stages such as flowering, can substantially alleviate the adverse effects of drought and improve agronomic traits and seed yield. Consequently, the integration of deficit irrigation practices with exogenous brassinosteroid application represents a synergistic and effective approach for improving productivity and sustainability in pinto bean cultivation under arid and semi-arid climatic conditions. Materials and MethodsTo investigate the effects of foliar application of 24-epibrassinolide on morphological and agronomic traits of pinto bean (Phaseolus vulgaris L. cv. Pinto), a split-plot experiment was conducted in a randomized complete block design (RCBD) with three replications in 2022 at the Research Farm of Yasouj University. In this study, the main factor consisted of three irrigation levels based on Class A pan evaporation data: full irrigation (100% of crop water requirement), moderate drought stress (80%), and severe drought stress (60%). The sub-factor included four levels of 24-epibrassinolide foliar application: control (distilled water), 0.05, 0.1, and 0.2 mg.L⁻¹. The foliar treatments were applied to the aerial parts of the plants during both vegetative and reproductive growth stages. The objective of this research was to evaluate the interactive effects of drought stress and 24-epibrassinolide application on growth indices, yield components, and the adaptive responses of pinto bean under limited water availability. Results and DiscussionThe results demonstrated that severe drought stress (60% of crop water requirement) led to a significant reduction in morphological traits, with leaf area index and plant height decreasing by 47.26% and 19.19%, respectively. In contrast, foliar application of 0.2 mg L⁻¹ 24-epibrassinolide significantly improved these traits, resulting in increases of 14.86% and 22.80% compared to the control. Furthermore, yield components including the number of pods per plant, the number of seeds per pod, and hundred-seed weight were markedly reduced under severe drought by 21.42%, 27.56%, and 12.69%, respectively. However, application of the highest 24-epibrassinolide concentration substantially enhanced these parameters, with increases of 105%, 61.56%, and 26.54% relative to the untreated control. The interaction between irrigation and foliar treatment revealed that under severe drought conditions, the application of 0.2 mg L⁻¹ 24-epibrassinolide led to notable improvements in seed yield (44.34%), biological yield (39.78%), and harvest index (7.29%) compared to non-treated plants. Moreover, the highest water use efficiency was recorded under severe drought stress combined with this level of 24-epibrassinolide application, indicating the compound’s significant role in optimizing performance under limited water availability. These findings highlight the protective and stimulatory effects of brassinosteroids in enhancing the growth and productivity of pinto bean under drought stress conditions. ConclusionOverall, these findings indicate that foliar application of 0.2 mg L⁻¹ 24-epibrassinolide can serve as an effective strategy to enhance agronomic traits, seed yield, and water use efficiency of pinto bean under both full irrigation and deficit irrigation conditions. This underscores the critical role of this plant growth regulator in improving drought tolerance and sustaining economic yield under water-limited environments. AcknowledgementsThe authors gratefully acknowledge the Research and Technology Deputy of Yasouj University for financial support of this experiment.
Introduction[1]Intercropping is the cultivation of two or more crops in the same area at the same time, used as a practical approach to enhance the sustainability of agroecosystems. This cropping system is applied to increase resource productivity and decrease production risk. In an intercropping system, plants of the leguminous family, due to some specific characteristics as high protein contents and biological nitrogen fixation, are used as an important component of intercropping. This study was performed in order to investigate the yield and yield components of isabgol (Plantago ovata Forsk) and peanut (Arachis hypogaea) under intercropping system conditions and to evaluate indices of land equivalent ratio, productivity and intercropping advantage. Materials and Methods This study was conducted at Jiroft University to evaluate the benefits of intercropping peanut and plantain in the subtropical climate of southern Kerman province. The experiment was conducted in a randomized complete block design with eight treatments and three replications in the 2015-2016 crop year. The experimental treatments were: 1- single peanut crop, 2- single plantain crop, 3- 20% plantain + 100% peanut, 4- 30% plantain + 100% peanut, 5- 40% plantain + 100% peanut, 6- 50% plantain + 100% peanut, 7- 75% plantain + 100% peanut, 8- 100% plantain + 100% peanut. Before planting the test plants, the physical and chemical properties of the soil were evaluated. Peanut density was kept constant at 25 plants per square meter, and psyllium density was added incrementally between peanut rows based on experimental treatments. The traits and indices studied were psyllium yield and yield components, peanut yield and yield components, and intercropping utility indices. The data variance analysis was carried out using SAS 9.4 software and mean comparison using Duncan test in significant level 5% and to evaluate the linear relationships between the studied quantitative variables, the Pearson correlation coefficient was calculated using standard statistical procedures. Results and Discussion Results showed that the number of shoot branches , pod weight, normal pods, biomass, seed dry weight per plant and grain yield were significantly (p<0.01) affected by the additive ratios of isabgol. The effect of these treatments on hollow pods and pod scurf was not significant. Increasing isabgol density ratio at intercropping caused a linear decrease (R2>90) in the number of shoots, pod weight, normal pods, biomass, and seed dry weight per plant. It is considerable that observed differences in these variables between peanut sole cropping and its intercropping with 20% and 30% isabgol addition treatments were not significant. Analyses of isabgol yield and its components indicated that, increase in isabgol density caused a significant (p<0.01) decrease in seed per spicule of isabgol and spicule per plant, but had no significant effect on 1000 seed weight of isabgol, whereas additive treatments of isabgol caused an increase in seed yield and biomass of isabgol per surface unit. The highest yield of Isabgol (69.07 g.m-²) was obtained under sole cropping, which showed no significant difference compared to the intercropping of 100% I + 100% P (67.63 g.m-²). The lowest yield (55.33 g.m-²) was recorded in the intercropping system of 20% I with 100% P. The highest productivity index (SPI=72.13) and intercropping advantage (IA=5.51) were obtained from the 100% peanut + 20% psyllium treatments. Conclusion Overall, considering the limited competitive ability of peanut at higher planting densities of isabgol, the cropping ratio of 20% psyllium + 100% peanut led to improvements in yield, yield components, and various indices of mixed cropping efficiency compared to sole cropping. Consequently, this treatment is recommended for tropical and subtropical conditions such as those found in Jiroft." Of course, this issue requires further studies. AcknowledgementsThis article is an extract from the final report of the research project 8-95-2828 approved by the Vice Chancellor for Research of Jiroft University. Therefore, thanks and appreciation are extended to Jiroft University for providing the costs of this project.
IntroductionGuar (Cyamopsis tetragonoloba L.) is an annual plant that tolerates salinity and drought from the legume family, which can be used as an alternative product in low-water plains. Considering the characteristics of the guar, such as having the ability to fix nitrogen biologically and a relatively deep root system, high adaptability to drought and poor soils, high competitive power and favourable morphology, it seems that placing it in intercropping, cultivation, can increase the efficiency of the final yield of intercropping crops. Utilizing the intercropping system for plants is an effective measure to improve soil fertility, increase the absorption of nutrients and improve the efficiency of water consumption, and it is considered one of the most important scientific methods to help maintain the stability and balance of the living system of soil. Therefore, this research was carried out with the aim of comparing different patterns of intercropping cultivation of guar next to the roselle (Hibiscus sabdariffa L.) with its pure cultivation at different levels of nitrogen fertilizer in the field of Toos Planting Manager Company in Taybad city, located in Polband plain. Materials and Methods The experiment was performed as a split plot in the form of a randomized complete block design with two factors and in three replications. The first factor included eight ratios of mixed crops, which were implemented as follows: sole cultivation of guar, one row of guar + one row of roselle, two row of guar + one row of roselle, three row of guar + one row of roselle, one row of guar + two row of roselle, one row of guar + three row of roselle, two row of guar + three row of roselle and three row of guar + two row of roselle. The second factor included nitrogen fertilizer, based on the recommendation of the soil laboratory, at three levels: without giving nitrogen fertilizer (zero kg per hectare) and 50 and 100 percent of the guar's requirement for nitrogen, one half at the time of planting and the other at the time of pod formation. Results and DiscussionThe results indicated a significant superiority of sole cultivation of guar treatment in 100 percent of guar's requirement for nitrogen fertilizer in terms of the number of pods per plant and the length of the roots. Nevertheless, in attributes of weight of one hundred seeds and pod length, a significant superiority changed in favour of the treatment of three rows of guar + one row of roselle under conditions of 100 percent of guar's requirement for nitrogen fertilizer. In attributes of shoot dry weight and seed yield, the two treatments of sole cultivation of guar and three rows of guar + one row of roselle, under the condition of providing 100 percent of the nitrogen fertilizer requirement, have a significant advantage and were placed in a statistical group. The study of roselle traits showed that, except for the three-row guar + one-row roselle treatment, all treatment levels of the intercropping arrangement showed the highest sepal dry weight under conditions of 100% fertilizer requirement. However, the results of the land equivalent ratio (LER) trait showed that the only treatment where LER was above one, is the treatment of one row of guar + three rows of roselle, under the condition of providing 50% of the N fertilizer requirement. ConclusionBased on the results of this research, the only treatment whose intercropping was justifiable is the treatment of one row of guar + three rows of roselle, under the condition of providing 50% of the N fertilizer requirement. Therefore, it seems that this intercropping combination is recommended for farmers who like this type of planting system. Doing intercropping for species with different phenology can increase the productivity of agricultural lands while creating biodiversity and guaranteeing production. AcknowledgementsWe hereby express our gratitude and appreciation to Mr. Engineer Jahangir, the respected managing director of Toos Planting Manager Company, who cooperated fully in the implementation and financing of this project.
IntroductionChickpea (Cicer arietinum L.), a cool-season legume, plays a vital role in sustainable agriculture and human nutrition due to its high protein content and nitrogen-fixing capacity. It contributes to crop rotation systems by suppressing weeds, reducing soil-borne diseases, and enhancing soil fertility. In regions with heavy-textured soils and high water-holding capacity, chickpea is typically sown in late autumn or early winter when soil moisture is adequate. Cultivated in over 56 countries, chickpea is often grown in semi-arid to arid environments, where abiotic stresses such as drought and cold limit its productivity. Its reproductive phase is especially sensitive to environmental stressors, making sowing date a crucial determinant of yield performance. Early sowing may extend the growth period and improve biomass accumulation, whereas late sowing can expose the crop to terminal drought. This study aimed to identify the optimal genotypes and planting dates for maximizing growth and yield under the cold and dry conditions of northwestern Iran. Materials and MethodsThe experiment was conducted during the 2019–2020 cropping season in Khusheh Darreh village, Saqqez County, Kurdistan Province, Iran (36°22′N, 46°34′E; 1502 m a.s.l.). A randomized complete block design (RCBD) with three replications was employed, evaluating five chickpea genotypes—including ‘Adel’ and ‘Mansour’—across five sowing dates: November 6, February 11, March 10, April 29, and May 22. Soil samples were collected at two depths (0–30 cm and 30–60 cm) for analysis of physical and chemical properties, and average climatic data were recorded. Morphological traits such as plant height, number of secondary branches, and number of pods, along with physiological indices including green emergence percentage, biological yield, seed yield, and harvest index, were measured. Results and DiscussionSowing date and genotype significantly affected all measured traits. The highest green emergence (82%) was recorded for the April 29 sowing date, whereas sowing in early December resulted in lower emergence due to cold stress. Late May sowing led to poor establishment caused by water stress. The February 11 sowing date produced the highest grain yield (652 kg/ha) and harvest index (48%), attributed to an optimal combination of growing season duration and favourable environmental conditions. Genotypic differences were evident, with ‘Adel’ and ‘Mansour’ performing best under early sowing conditions, reflecting their superior tolerance to cold and extended vegetative growth. Late sowing restricted plant development and yield due to a shortened growth period and terminal drought. Early sowing (in the absence of frost damage) allowed for prolonged growth, improved utilization of light and moisture, and more effective resource allocation, enhancing both vegetative and reproductive traits. Pod number and seed number were identified as key determinants of yield, consistent with previous findings. Environmental stress during the flowering and pod development stages resulted in an increased number of empty pods and reduced seed weight, highlighting the importance of aligning crop phenology with climatic conditions. The study also confirmed that Desi-type chickpeas exhibit greater resilience to abiotic stresses compared to Kabuli types. Tailoring sowing dates to genotype-specific growth patterns and climatic forecasts is essential for sustainable chickpea production in cold and water-limited regions. ConclusionThis research emphasizes the critical role of sowing date in optimizing chickpea performance under cold, dry agro-climatic conditions. Among the treatments, sowing on February 11 combined with genotypes such as ‘Adel’ and ‘Mansour’ resulted in superior growth and yield. The findings highlight the importance of location-specific agronomic planning that integrates genotype selection with optimal sowing time. These results offer practical recommendations for enhancing chickpea productivity in highland areas prone to cold and drought stress. Future research should investigate the physiological mechanisms behind genotype responses and explore integrated crop management strategies for further yield stabilization. AcknowledgementsThe authors thank the Agricultural Research Station of Kurdistan Province for providing the research site and technical support. Special appreciation is extended to the local farmers of Saqqez for their cooperation and logistical assistance during the fieldwork.
Introduction Rice (Oryza sativa L.) is recognized as one of the earliest cultivated crops, providing essential nutrients for human growth and health. One of the major challenges today is the severe limitation of arable land available for rice production. This issue is particularly critical in countries with arid and semi-arid climates and limited water resources, such as Iran, where rice cultivation requires substantial amounts of water. Ecological intensification is an approach that optimally utilizes natural resources to enhance productivity while minimizing negative environmental impacts. The present study aimed to investigate the effects of various cultivation systems on the quantitative and qualitative characteristics of rice (Tarom Hashemi cultivar). Materials and MethodsThis study was conducted through two separate experiments based on a randomized complete block design with four replications, under nursery and field conditions in the city of Babol, Iran, during the 2022 and 2023 growing seasons. The experimental treatments included three cultivation systems: the System of Rice Intensification (SRI), an intermediate system, and a traditional system. In the nursery, seed densities for the ecological intensification, intermediate, and traditional systems were set at 100, 200, and 300 g.m-², respectively. In field conditions, treatments included transplanting ages of seedlings (20, 30, and 40 days), planting densities (25, 30 and 20 plants.m-2), irrigation regimes (water deficit as alternative water, saturated irrigation at the soil level, and permanent waterlogging in 10 cm above the soil), and the number of seedlings (1, 4, and 8 seedlings per hill). The traits under investigation included seedling length, stem diameter, and root diameter at the time of transplanting from the nursery to the field. Evaluated quantitative traits included growth characteristics (panicle length), yield components (percentage of unfertile grains and number of productive tillers), biological yield, paddy yield, harvest index, and quality traits (amylose content and gel consistency temperature). Results and DiscussionThe results from the nursery experiment indicated that the main effect of planting systems on stem length, stem diameter, and root diameter of seedlings was significant. Except for root length, the interaction between year and planting systems was not significant for the other traits in the nursery. In the ecological intensification system, stem diameter, stem length, and root diameter measured 24.5 cm, 4.1 mm, and 0.52 cm, respectively. In both years, the longest root length observed was 13 cm in the ecological intensification system. In contrast, the lowest values for these traits were recorded in the traditional system. The examination of quantitative traits of rice in field conditions revealed significant interaction effects between year and planting systems on the number of fertile tillers. The highest number of fertile tillers was recorded for SRI. The effect of planting systems was significant on both biological yield and paddy yield. The maximum biological yield (2.9 kg/ha) and paddy yield (0.83 kg/ha) were associated with SRI. The highest amylose content and gel consistency temperature were found in the ecological intensification system (with 22.7% and 3.7, respectively), while the traditional system exhibited the lowest values (with 21.5% and 3.0, respectively). Correlation coefficients between paddy yield with panicle length (r = 0.98**), number of fertile tillers (r = 0.99**), and biological yield (r = 0.97**) were all positive and statistically significant at the 1% probability level. Conclusion Overall, the results of this study demonstrate that the ecological intensification system outperformed the other management systems and can be considered an effective approach in ecological management. This contributes to sustainable production, food security, and improvements in environmental characteristics.
IntroductionCowpea (Vigna unguiculata) an annual legume, originated in Iran. It is one of the main sources of protein, amino acids, vitamins, minerals, and energy, and therefore is important for a well-balanced diet with good nutritional value. In recent years, the application of organic fertilizers has increased tremendously in agricultural production. Humic compounds such as HA is one of the organic-mineral fertilizers, which is commonly used for the production of crops. In order to increase the quantitative and qualitative traits of plants, the extract of some plants, such as green tea extract and coffee extract, can be used. Materials and MethodsIn order to investigate the effect of biofertilizers, including humic acid, green tea extract, and coffee extract, on the improvement of pigments and physiological traits of cowpea, an experiment was designed and implemented in 2023 at a private farm in Semnan city. The experiment was a factorial format based on a randomized complete block design with three replications. The test treatments include seed priming at five levels (control, distilled water, humic acid (750 mg/liter), green tea extract (10% concentration) and coffee extract (10% concentration)) and foliar spraying at four levels (control, humic acid (750 mg/liter), green tea extract (concentration 10%) and coffee extract (concentration 10%). Pretreatment of seeds with desired concentrations was done for six hours, following the principles of seed aeration. Foliar spraying was done at the beginning of flowering. Seeds were sown on June 25 (as the second planting). Before planting, all the seeds were disinfected with benomyl and then in each plot, four rows of five meters were planted with a distance of 25 cm between the rows and 8 cm within the row at a depth of 5 cm.Results and DiscussionThe results showed that pretreatment of seeds with humic acid, green tea extract and coffee extract led to an increase in the traits of relative leaf water content, membrane stability index, leaf surface index, photosynthetic pigments, protein yield, and grain yield. In plants grown from pre-treated seeds, the amount of malondialdehyde and soluble carbohydrates in leaves decreased to a significant level. Foliar spraying with these substances led to the improvement of leaf surface index, the amount of photosynthetic pigments, protein yield, and seed yield. Application of foliar spraying also reduced the amount of malondialdehyde and soluble carbohydrates in leaves. Finally, within the scope of the research, the use of humic acid at the rate of 750 mg/liter and green tea at a concentration of 10% is recommended as seed pre-treatment and foliar spraying in the field. More research is needed on the recommendation of seed pretreatment and coffee extract foliar spraying. When seed yield was considered as a dependent trait, the traits of leaf surface index (0.6076), carotenoid (0.7265), membrane stability index (0.6501), leaf soluble carbohydrates (-0.6678), and Malondialdehyde (0.6096) entered the model as main variables. The results of this research showed that carotenoid (0.3764) and membrane stability index (0.2950) had the most positive direct effect on grain yield.ConclusionThe results of this research showed that the photosynthetic pigments, protein yield, and grain yield of cowpea increased to a significant level by using humic acid, green tea extract, and coffee extract as seed pretreatment and foliar spraying. Seed protein percentage, yield components, and grain yield of cowpea increased to a significant level with the application of humic acid, green tea extract, and coffee extract as seed pretreatment and foliar spraying. Finally, within the scope of this research, the use of humic acid at the rate of 750 mg/L and green tea at a concentration of 10% is recommended as seed pretreatment and foliar spraying in the field. More research is needed on the recommendation of seed pretreatment and foliar spraying of coffee extract.
IntroductionThe growing global population, coupled with the scarcity and limitations of food resources, has prompted researchers and agricultural professionals to seek more effective solutions for feeding millions of people, particularly in developing countries. Guar (Cyamopsis tetragonoloba L.) is an annual legume known for its tolerance to salinity and drought, making it a promising alternative crop for low-water plains. Determining the appropriate planting date and optimal plant density are crucial factors that contribute to the efficient use of environmental resources and achieving high yields. Materials and MethodsThis experiment was performed in the form of split plots based on a randomized complete block design with three replications in 1398 in Mohammadieh Agricultural Research Station, Birjand. Experimental factors include planting date in four levels (May 10, June 10, June 25 and July 10) as main plots and plant density in three levels (distances of 10, 20 and 30 cm between plants in a row) as plots Guar cultivar was a Pakistani mass that was prepared from Pakan Bazar Isfahan Company. For planting, the land was plotted after preparation so that each plot consists of 4 ridges 60 cm wide and 3 m long, and on each row of two rows was planted manually at a depth of five centimeters, and irrigation was carried out immediately. After reaching the final height of Guar plant and physiological maturity before final harvest, taking into account the marginal effect of five plants from each plot, they were randomly selected and the characteristics of plant height, number of sub-branches per plant, pod length, number of pods per plant, number pods per plant, 1000-seed weight, initial plant weight, plant weight without pods and pod weight were measured. The number of pods per square meter, plant yield, and biological yield were calculated after removing the marginal effects based on plants harvested from one square meter in the middle of each plot. Data were analyzed using SAS software (V9.1) and comparisons of means were performed by Duncan method at 5% level and graphs were drawn with Excel.Results and DiscussionOne of the most important fields of research on legumes is the study of different environmental conditions affecting their quantitative (biological) yield and economic performance. Therefore, studying and obtaining the best growing environment conditions that can lead to crop production with the highest economic yield is one of the most important goals in research related to the cultivation of legumes. The results of the present study showed that seed yield and its components were affected by planting date and with delay in planting, the amount of studied traits was significantly reduced, so that this decrease was more in the planting date of 10 July because the planting date late exposure of guava plants to adverse conditions such as lower temperature, more humidity and less day length at the end of the growing season and causes a decrease in grain yield. Also, in this experiment, planting density levels on the studied traits were significant, and according to the results of the experiment, it can be stated that with increasing plant density, the distribution of sources such as light, nutrients, and moisture between plants was more favorable. It led to an increase in grain yield and biological yield per unit area, so that the highest grain yield and biological yield were obtained at the highest density (10 cm distance between plants per row). Therefore, planting at higher plant densities will probably be economically justified. ConclusionsBased on this research, it can be concluded that planting guar in early June with a spacing of 10 cm between plants yields the highest productivity and optimal crop components.
Introduction Safflower, scientifically known as Carthamus tinctorius L., is an annual plant belonging to the Asteraceae family. Today, with the development of high-yield varieties that produce substantial quantities of high-quality oil, safflower is recognized as one of the world's important oilseed crops. Given its strong resistance to salinity and ability to grow under rain-fed conditions, it is considered a drought-tolerant plant—an attribute that significantly enhances its value. Additionally, humic acid, as an organic compound, poses minimal harm to the environment. Additionally, through its hormone-like activity, it has many positive effects on various traits, including performance characteristics. The presence of micronutrients, especially Fe, enhances the plant's resistance to various biotic and abiotic stresses. Materials and Methods This study was conducted at the Ardabil Agricultural Research Center to evaluate the effect of two types of fertilizers (iron fertilizer and humic acid) on the yield and phenological traits of two safflower cultivars. This experiment was conducted as a split-plot design based on a completely randomized block design with three replications. The main factor included two safflower varieties named "Chini" and "Goldasht," while the sub-factor consisted of nine fertilizer levels. These fertilizer levels included one control level, two levels of 95% humic acid (two milligrams per liter and four milligrams per liter), two levels of 12% EDTA chelated iron (one milligram per liter and two milligrams per liter), and four combined levels of iron and humic acid fertilizers. Results and Discussion The results revealed a significant difference in performance traits between the two varieties, Chini and Goldasht. Observations showed that the Goldasht variety produced a significantly higher seed yield of 1,462.5 kg per hectare, compared to 1,403.3 kg per hectare for the Chini variety. Additionally, the second level of iron + second level of humic acid treatment showed significantly the highest yield, resulting in a 49% increase in seed yield compared to the control. Overall, the combined use of these two fertilizers is recommended. The Goldasht variety requires a shorter time for flowering and maturity compared to the Chini variety and matures earlier while also having a higher yield, making it preferable in this regard. For the traits of plant height and antioxidant activity, there is no significant difference among the cultivars. However, among the fertilizer levels, the second level of humic acid resulted in a height of 68.3 cm, and for antioxidant activity, the combination of the second level of humic acid and the second level of iron exhibited the highest activity at 84.5%. Overall, among the cultivars, 'Goldasht' and among the fertilizer levels, the treatment combining the second levels of iron and humic acid had the highest biological yield, the highest harvest index, oilseed yield, and seed yield. Humic acid, due to its nitrogen-like effects and its richness in organic materials, leads to increased seed filling and higher thousand-grain weight. On the other hand, the application of iron helps to cleanse reactive oxygen species and improves the plant's sink performance, providing more seeds for filling. Conclusion The studies indicated that the Goldasht variety matures earlier and yields more than the Chini variety. Due to its longer growth period, the Chini variety is more susceptible to late-season challenges such as heat stress, pests, and bird damage, which can negatively affect yield. Therefore, the cultivation of the Goldasht variety is preferable in this context. In terms of physiological traits, the application of iron and humic acid fertilizers was found to enhance the stability and resilience of both varieties. The interaction between humic acid and iron proved beneficial for safflower health, promoting greater nutrient uptake, improved growth parameters, increased seed yield, and enhanced stress tolerance.
IntroductionRainfed farming plays an important role in the food production of many countries in the semi-arid regions of the world and includes 80% of the total usable agricultural land. Barley is cultivated in most parts of the world in areas that are threatened by moisture stress, the lack of which affects different stages of plant growth from germination to seed set, and finally affects the grain yield. Studies show that the stress caused by the lack of water in plants is one of the important factors in crop reduction in semi-arid regions. Application of biofertilizers improves yield by improving the physical properties of the soil, increasing soil fertility, and increasing the availability of nutrients for plant uptake, among which mycorrhizal fungi are considered the most important microorganisms. Mycorrhizal fungi are effective in nutrient uptake, including phosphorus, water uptake in dehydrated conditions, hormone production, modulation of environmental stresses, improvement of root growth, and effect on soil granulation. Since not much research has been done on the application of mycorrhizal fungi on dryland barley in the country and especially in Ilam province, the present experiment was conducted to investigate the effect of mycorrhizal fungi on yield, yield components, and gas exchanges of dryland barley. Materials and MethodsIn order to investigate the effect of mycorrhiza inoculation on yield and yield components and gas exchange of barley cultivars under rainfed conditions, a field experiment was carried out in factorial analysis based on a randomized complete block design with three replications at the farm of Sarablah Agricultural Research Center station during the 2019-2020 cropping season. Experimental treatments include barley cultivars (Mahali, Mahour, Khorram, and Fardan) and fertilizer sources treatment, including control (no fertilizer source), 50% phosphorus fertilizer, mycorrhizal fungi (Glomus mosseae, Glomus etunicatum, and Rhizophagus irregularis), and Mycorrhizal fungi were +50% phosphorus fertilizer and 100% phosphorus fertilizers. In this study, the length of each plot was four meters, the number of rows in each plot was eight rows, and the distance between the rows was 20 cm. The measured traits were: yield and yield components, as well as gas exchanges, including photosynthetic rate, transpiration rate, photosynthetic water consumption efficiency, mesophilic conductance, co2, and leaf temperature. The effect of the treatments on yield and yield components and gas exchange of the barley cultivars in the field was assessed using SAS; software, means were compared by Duncan's multiple range test method, and graphs were drawn using Excel software.Results and DiscussionThe results of this study showed that the interaction of cultivar×fertilizer sources on yield, grain yield components, as well as gas exchange characteristics, including photosynthetic mesoton, transpiration rate, photosynthetic water consumption efficiency, mesophilic conductance, substomatal carbon dioxide concentration, and leaf temperature in rainfed barley was significant. So that the maximum number of seeds per spike (32.3 seeds), 1000-grain weight (38.5 g), grain yield (4238.3 kg/ha), biomass yield (10123.3 kg/ha), photosynthesis rate (5.7 µmol Co2 m-2s-1), transpiration rate (4 mmol H2o m-2s-1), mesophilic conductivity (0.019 mmol co2 M-2S-1) and water use efficiency Photosynthesis (µmol co2 mol-1H2o) was obtained in Fardan cultivar ×Mycorrhiza+50% of phosphorus fertilizer compared to the control (no fertilizer source was used). Conclusion The results of this study showed that under rainfed conditions, yield and yield components, photosynthesis rate, transpiration rate, mesophilic conductance, and photosynthetic water use efficiency in all cultivars of barley were significantly reduced. However, the use of mycorrhizal fungi in dryland conditions improved grain yield and gas exchanges. In this study, Barley Fardan×application of Mycorrhizal fungi caused a significant increase in yield and grain yield components by increasing photosynthesis and increasing photosynthetic water use efficiency, as well as decreasing leaf temperature.
