Rice cultivation is severely affected by Nilaparvata lugens St & aring;l, which causes significant yield losses. Host-plant resistance is the most effective and eco-friendly approach for managing this insect. This study assessed the resistance of eight rice genotypes, namely RP 2068-18-3-5, RP Bio 4918-230S, Salkathi, IRG-309, IRG-221, IRG-98, IR-64, and MTU-1010, against brown planthopper (BPH) under greenhouse conditions using PTB 33 as the resistant check and TN-1 as the susceptible check, and also examined the biochemical basis of resistance. Plant responses were measured in terms of antixenosis, antibiosis, and tolerance. Among the test entries, RP 2068-18-3-5 and Salkathi showed least damage, similar to the resistant check PTB 33, while the susceptible genotypes showed higher honeydew secretion and fecundity. IRG-98 showed high antibiosis, evidence by increased feeding marks along with reduced nymphal emergence and egg hatchability. Biochemical studies showed increased superoxide dismutase (SOD) activity in all genotypes after infestation, with maximum induction in the resistant genotypes. In contrast, elevated catalase (CAT) activity was in the susceptible check, indicated a detoxification response. Peroxidase (POD) and polyphenol oxidase (PPO) activities were higher in all genotypes, with constant induction in IRG-98 and PTB 33. Correlation analysis revealed negative correlations of nymphal survival and honeydew secretion with SOD, POD, and PPO activities, and a positive correlation with CAT activity. Principal Component Analysis (PCA) effectively differentiated susceptible and resistant genotypes based on their biological and biochemical characteristics. The results of this study provide valuable information on the identification of potential sources of resistance to BPH and highlight the coordinated role of antioxidant enzymes in resistance breeding and sustainable pest management.

The impact of surface heat flux (9000 <= q" <= 26000 W/m2) on the heat transfer behavior of water-mist assisted air jet impinging normally on a flat surface has been investigated in the present work. An experimental facility consisting of mist generation system, heating unit, temperature measurement & acquisition system, and experimental image capturing equipment was built. The heat transfer behavior is explained with the help of direct experimental images of droplet deposition on the flat surface at steady state for different operating conditions. A comparison of heat transfer behavior of water-mist assisted air jet impingement and air jet impingement has also been presented. Additionally, the heat transfer behavior for water-mist assisted air jet impingement at different operating parameters such as Reynolds number of air (9048 <= Rea <= 21113), loading fraction of water (1.2% <= f <= 2%), and normalized distance between nozzle and target surface (20 <= H/Do <= 60) has been analyzed. The heat transfer decreases with increase in surface heat flux due to a decrease in water droplet deposition with increase in heat flux, leading to lower conductive and convective heat transfer through droplet deposition at high heat flux. The heat transfer increases significantly with increase in air Reynolds number compared to increase in water loading fraction. Further, it was found that heat transfer decreases with increase in nozzle to plate distance.

Defining and forecasting the life cycle and population dynamics of thrips depend on understanding their developmental and reproductive responses to varying temperatures. The goal of this investigation was to gather precise data on biological fitness and demographic parameters of Thrips parvispinus on two selected hosts (Chilli, Capsicum annuum; Solanaceae and Beans, Phaseolus vulgaris; Leguminosae) at four constant temperatures (15, 20, 28 and 30 degrees C). The total pre-adult duration found longest at 15 degrees C and shortest at 30 degrees C on beans, while longest at 20 degrees C and shortest at 30 degrees C on chilli. Adult longevity was recorded longest at 15 degrees C and the shortest at 30 degrees C on both beans and chilli depicting that 30 degrees C shortened the adult lifespan of T. parvispinus. Fecundity was documented to be highest on beans and chilli at 30 degrees C, and lowest at 20 degrees C on beans and on chilli at 15 degrees C. The total pre-oviposition period was found to be shortest at 30 degrees C both on beans and chilli. Significant differences in the population parameters revealed net-reproductive rate and finite rate of increase to be highest at 30 degrees C on both chilli and beans. The shortest mean generation time was recorded at 30 degrees C on both chilli and beans. This study is first of its kind in investigating the comparative biology of T. parvispinus on chilli and beans under different temperatures. Since, there exists a lack of knowledge on the fitness traits and demography of T. parvispinus, these findings would prove significant for predicting population responses to climate change and tailoring integrated pest management strategies.

This work presents the optimization and performance evaluation of AlGaN/GaN high‐electron‐mobility transistors (HEMT) devices through comprehensive Technology Computer‐Aided Design (TCAD) simulations. The conventional experimental device is accurately calibrated to serve as a baseline for analysis. The barrier thickness T B is analyzed from 25 to 4 nm, and energy band analysis indicated that a thickness between 25 and 7 nm is optimal for creating a strong two‐dimensional electron gas (2DEG). The analysis of sheet carrier density further supported the selection of 7 nm as the preferred T B . Simultaneously, gate length L G scaling from 250 to 100 nm is conducted to assess its impact on device performance. The optimized device achieved a peak transconductance g m of 534 mS mm −1 , an 67% improvement over the conventional design. The device also achieved a maximum cut‐off frequency f T of 74 GHz and a maximum oscillation frequency f max of 97 GHz. These results demonstrate that the optimized device structure is highly suitable for advanced communication.

The present study investigated the impact of weed interference, Trianthema portulacastrum L. and Paspalum distichum L., on the physiological, biochemical, and yield levels of greengram (Vigna radiata) under different environmental conditions, including ambient, elevated CO2 (550 ± 50 ppm), elevated temperature (ambient + 2 °C), and a combination of elevated CO2 and temperature. The findings demonstrated that weed interference caused an oxidative burst, as evidenced by the increased accumulation of superoxide ions and malondialdehyde levels in weed-infested greengram compared to weed-free plants across all environmental conditions. Furthermore, various parameters including membrane stability index, photosynthetic rate, protein content, and yield were significantly reduced under weed infestation in comparison to weed-free greengram, irrespective of the environmental conditions. The highest accumulation of superoxide ions was observed under elevated temperature conditions, primarily due to the biotic stress induced by P. distichum (49.39 µmol g− 1 fresh weight) and T. portulacastrum (60.30 µmol g− 1 fresh weight). Similarly, under elevated temperature, the malondialdehyde content of greengram increased by 10.32 µmol g− 1 fresh weight and 14.02 µmol g− 1 fresh weight in the occurrence of P. distichum and T. portulacastrum, respectively. Additionally, a significant reduction in yield (1.99 g) was observed under elevated temperature conditions. In contrast, elevated CO2 conditions resulted in increased yield (7.80 g) compared to ambient, elevated temperature and combined effect of elevated CO2 and temperature due to higher membrane stability index, relative water content, photosynthetic rates, and protein level. Overall, this study highlights the detrimental impact of weed interference on greengram yield under changing environmental conditions. T. portulacastrum was found to cause a higher reduction in greengram yield. These results impart valuable insights into the ecological and agronomic aspects of weed management strategies, especially in the context of climate change, aiming to enhance crop productivity and sustainability.

Kinnow mandarin (Citrus reticulata Blanco) is a valuable fruit crop mainly grown in the North Indian states of India due to its high-quality juice content. Psylla (Diaphorina citri Kuwayama), whitefly (Dialoeurodes citri Ashmead), sooty mould (Capnodium citri) and dieback (Colletotrichum gloeosporioides) pests are the most important biotic constraints affecting its fruit yield up to 70 percent. To manage these pests, farmers often use mixture of non-label claim pesticides (quinalphos 25%EC, lambda-cyhalothrin 2.5%EC, diafenthiuron 50%WP, chlorantraniliprole 18.5%, cymoxanil 8% + mancozeb 64% WP, etc.) without achieving the desired effect. Hence, area-wide implementation of the Integrated Pest Management (IPM) strategy in Kinnow mandarin was implemented during 2021-2023 covering 5 villages at Hisar, Haryana. Among the IPM strategy, installing yellow sticky traps @ 20/ha, neem seed kernel extract spray @ 5%, and imidacloprid 17.8SL @ 0.3% reduced the whitefly and psylla populations. The spray of 1% starch and dipping infected fruits in a bleaching solution @ 0.1% reduced the severity of sooty mould disease. Pruning and destruction of dead twigs followed by a spray of copper oxychloride 50 WP @ 0.3% were found very effective too. The lowest average population of psylla and whitefly were recorded in T1-IPM compared to T2-farmer practice and T3-control, respectively. Minimum average disease severity of sooty mould and dieback was noticed in T1-IPM compared to T2-farmer practice while the highest disease severity was recorded in T3-control. Population dynamics of psylla, whitefly and sooty mould, dieback severity, and Area Under Diseases Progress Curve (AUDPC) were found to vary during 11th to 52nd standard meteorological week (SMW). They were observed to be highest in T3-control treatment, followed by T2-farmer practice and T1-IPM. The highest natural enemy’s populations (Coccinellid, Chrysoperla, and spider) were recorded in T3-control followed by T1-IPM, and then in T2-farmer practice treatment. The highest average fruit yield and B: C ratio was recorded in T1-IPM compared to T2-farmer practice and T3-control treatment. The validated IPM strategies can be adopted by Kinnow mandarin growing farmers as an economically viable option for the management of psylla, whitefly, sooty mould, and dieback pests.

Ecology relies on collecting, integrating, and interpreting large volumes of diverse data, which remains a greater challenge for ecologists. Ecoinformatics could provide a solution that integrates agricultural and ecosystem sciences with computer sciences, geographic information sciences and quantitative methods. It provides tools and techniques for organizing and converting ecological data into information and knowledge. The use of ecoinformatics in entomology progresses from documenting pest and disease patterns and their colonization, pest impact on crop yield to the food web and farmer’s decision making. However, there are still numerous obstacles to overcome, particularly when it comes to integrating ecoinformatics methods into mainstream research and education. Several technical and sociocultural challenges like collaboration with statisticians, developing data sources, data privacy concerns and developing mobile platforms for pest management remain some of the major hurdles. Since it is akin to experimental methodology, ecoinformatics-based techniques when well-integrated, give a more optimal solution to pest management problems than any single strategy employed independently.

Aim: In the present study, disease surveillance with applied ICT was carried out in Banana (Musa sp.) to assess the severity of leaf spot disease in major banana growing areas of Maharashtra from 2012-2022. Methodology: During the study period, observations of disease severity were recorded from two fixed orchards by field scout. Twenty plants were randomly detected and examined for leaf spot disease. The scoring was done based on 15 leaves per plant. Data were analysed by One-way ANOVA and the statistical procedures were performed with R programme. Results: Data of ten seasons on the leaf spot disease monitoring on banana revealed that, the disease commenced in the month of August-September in Maharashtra. The increased incidence was observed in the month of October with 6 to 15% severity of leaf followed by November (2 to 5% severity on leaf area) in monitored orchards. Interpretation: Implementation of management options before the onset of October and November for leaf spot disease may greatly help the farming community in saving banana crop disease. This will also help plant protection workers to develop integrated disease management strategies. The study offers farmers timely advice on disease management. Key words: ICT tools, Leaf spot disease, Musa sp., Wide-area pest surveillance

ABSTRACT Remote sensing is being increasingly used in agricultural stress management, offering real‐time analysis of crop stress beyond what can be observed visually alone. Hopper burn, induced by brown planthopper (BPH, Nilaparvata lugens ) is a significant challenge to rice production in India. This study aims to characterize the spectral reflectance of rice plants with different infestation levels of 2 nd instar BPH nymphs across three varieties namely Pusa Basamti‐1509, Pusa Basmati‐1121, and TN‐1 (susceptible variety to BPH). The differential infestation included 0, 5, 10, 20, 40, 80, 100, 200 number of nymphs. The spectral signatures of the crop were collected at 20 and 40 days after infestation (DAI). The results indicated a distinct change in reflectance pattern between healthy and infested rice plants across all three varieties in green (490–559 nm), yellow (560–584 nm), orange (585–639 nm), and red (640–699 nm) region of visible portion as affected by chlorophyll pigments and in NIR region (700–1800 nm) as affected by cell structure and in water absorption (1915 nm) region of SWIR portion. The specific wavelength band (470, 660,750, 1800, 1915 nm) showing a correlation above 0.8 with pest severity level, was identified as sensitive for assessing BPH damage. Analysis of reflectance changes across wavelengths highlighted that the first derivative has a strong correlation between BPH severity and reflectance in the green region (500–540 nm) and red edge position (680–760 nm). The amplitude of the red edge value decreased with an increase in the severity level of insects. This study identifies the sensitivity of visible and near‐infrared regions in detecting and assessing BPH infestation severity.

Rice (Oryza sativa L.) encounters significant challenges from insect pests, among which the brown planthopper (BPH), Nilaparvata lugens is particularly damaging. Plants respond to this stress by generating reactive oxygen species (ROS), demanding effective defense mechanism. Superoxide dismutase (SOD) and catalase (CAT) are important antioxidant enzymes that neutralize harmful ROS. Our research investigated SOD and CAT activity changes in these germplasm under BPH infestations after 96 h. Initial observations identified discrete SOD and CAT activity differences among germplasms, with PTB 33, Salkathi, RP 2068-18-3-5 and IRG-98 showing the highest and lowest activity respectively. After BPH feeding, SOD and CAT activities gradually increased in resistant germplasms up to 96 h indicating the biochemical based resistance mechanism.

Cauliflower, a widely cultivated vegetable crop valued for its edible curds, faces a persistent threat from insect pests, which are typically managed using synthetic insecticides. This study evaluated the benefits of intercropping practices as part of an ecological pest management strategy in cauliflower cultivation during the winter seasons of 2017–18 and 2021–22. Nine insect pests belonging to six families of three orders were recorded. The calendula intercropping system (IS) consistently showed the lowest infestation by Plutella xylostella and Pieris brassicae/plant. Calendula IS had attracted the highest numbers of syrphids, Cotesia glomerata, Diaeretiella rapae, Cotesia vestalis, and coccinellids such as Coccinella septempunctata and Cheilomenes sexmaculata. In candytuft IS, a strong tri-trophic interaction between the flower and D. rapae significantly reduced aphid populations, for each additional D. rapae, aphid numbers decreased by 48.53 in 2018. The marigold IS recorded the highest Shannon diversity index in 2021–22. The longest adult survival of C. septempunctata (8.67 ± 3.35 days), in the absence of aphids was recorded on candytuft flowers. The total sugars and protein in flowers positively influenced the longevity of the adult coccinellid beetles (R2-40.42 and 20.79%, respectively). Calendula intercropping yielded the highest revenue return of Indian rupee (₹) 11.33 per INR 1 invested, compared to the cauliflower monocrop (1.58). These findings demonstrate that, intercropping and habitat manipulation can enhance ecological pest control and reduce the dependence on synthetic chemicals.

The air/water mist jet impingement phenomenon on a flat target with constant heat flux has been studied experimentally and numerically. The effects of various operational variables on the heat transfer characteristics of the mist jet have been analyzed through an experimental study. These variables are the air Reynolds number (Rea = 5305-10297), the mist loading percentage (f = 0 %-1.5 %), and the nozzle-to-plate spacing ratio (H/Do = 20-40). Additionally, the computational study investigates the effects of the nozzle ratio parameter (Di/Do = 0.1-0.3) and droplet diameter (2 mu m-100 mu m) on mist jet impingement. A comparison between Eulerian-Eulerian and Eulerian-Lagrangian modeling techniques for simulating the air/water mist jet has been provided. The current computational findings based on the Eulerian-Eulerian method accord well with the experimental data, with an accuracy of 15 %; however, numerical predictions using the Eulerian-Lagrangian approach deviate significantly from the experimental results, with errors of up to 65 %. The increase in Rea results in a greater improvement in the stagnation point Nusselt number, up to 85.32 %, compared to 34.99 % with an increase in f. Furthermore, a rise in f causes a greater spread of the mist jet flow in the domain and on the target impingement surface than an increase in Rea. When Di/Do increases from 0.1 to 0.3, the stagnation point Nusselt number increases by approximately 55.67 %. In addition, the spread of the mist jet flow in the domain increases as the Di/Do ratio increases. Experimental correlations have been developed based on studied parameters for calculating the Nusselt number values on the flat target.

Johnsongrass [Sorghum halepense (L.) Pers.] is a menace in several crops including grain sorghum, maize, cotton, soybean, etc. due to its ability to compete for space, nutrients, and light. It is classified as one of the world’s worst weeds and is a target for eradication efforts worldwide. While prevention remains the most effective strategy for managing its spread to new areas, an alternative approach involves leveraging its economic potential through applications such as animal feed, manure, bioremediation, soil binder, etc. For example, johnsongrass serves as fodder grass in many regions, boasting high protein content (10-12% dry matter) and total digestible nutrients (50-60%). Similarly, it exhibits phytoremediation properties, extracting pollutants from soil and water. Despite its potential, research into the utilization of johnsongrass remains limited. Therefore, this article seeks to consolidate the available knowledge on its economic applications, including its genetic potential in sorghum breeding, role as livestock feed, human health benefits, soil conservation properties, industrial uses, etc. By shedding light on the diverse uses of johnsongrass, this article aims to promote awareness and encourage the transformation of noxious weeds into sources of wealth.

Climate change factors, including elevated carbon dioxide (eCO2), elevated ozone (e03), and the combined effect of elevated temperature and CO2 (eT+eCO2), significantly influence the population dynamics, development, and feeding behavior of the Brown Planthopper (Nilaparvata lugens, BPH) and its impact on rice yield. A two-year field study (2019–2020) showed that BPH populations were highest under eCO2 (61.6 ± 13.5 and 50.6 ± 12.3 N. lugens/hill) and moderate under eT+eCO2 (44.5 ± 9.4 and 47.5 ± 12.1 N. lugens/hill), while e03 drastically reduced populations (17.7 ± 3.1 and 25.1 ± 7.0 N. lugens/hill). Fecundity followed a similar trend, with the highest egg production under eCO2 (219.7 ± 3.3 and 234.3 ± 9.7 eggs/female), moderate under eT+eCO2 (194.2 ± 6.3 and 223.5 ± 9.2 eggs/female), and lowest under e03 (108.4 ± 6.0 and 135.6 ± 3.7 eggs/female). Developmental duration was shortest under eT+eCO2 (14.9 ± 0.3 and 15.9 ± 0.4 days) and longest under e03 (18.2 ± 0.40 and 21.7 ± 0.40 days). Feeding intensity, indicated by honeydew excretion, was highest under eCO2 (124.8 ± 5.3 and 131.3 ± 4.2 mm²), reduced under eT+eCO2 (105.7 ± 4.9 and 107.6 ± 3.4 mm²), and lowest under e03 (44.2 ± 2.5 and 48.9 ± 2.6 mm²). Results indicated that eCO2 promoted overall plant growth, with the highest plant height (65.4 ± 0.8 cm) and reproductive tillers (22.2 ± 0.6). However, under BPH infestation, eCO2 also resulted in the highest yield reduction (15.9%) despite producing the highest grain yield under uninfested conditions (40.1 ± 0.3 g/hill). The eT+eCO2 treatment exhibited moderate reductions in plant height (62.4 ± 0.6 cm) and grain yield (38.1 ± 0.4 g/hill), with a yield loss of 11.5% under infestation. The e03 treatment negatively impacted plant growth, significantly reducing plant height (54.8 ± 1.0 cm), total tillers (17.7 ± 0.9), and grain yield (27.5 ± 0.2 g/hill) in uninfested conditions, with a lower yield reduction (8.72%) under infestation. The findings of this study indicate that pests and host plants benefited under eCO2 and eT+eCO2 conditions; however, increasing BPH populations caused yield losses. Nevertheless, e03 had a detrimental effect on pests as well as host plants. The results pertaining to the collective impact of climate change factors on both the host plant and pests have the potential to contribute to the advancement of insect pest management strategies in response to shifting climates.

Understanding nitrogen use efficiency (NUE) in wheat is crucial for identifying genotypes that can maximize yield with minimal nitrogen input. Despite advancements in the field, optimizing NUE across diverse environmental conditions and nitrogen levels remains challenging, particularly in identifying varieties capable of sustaining high yields with lower nitrogen inputs. A field experiment was conducted to evaluate the NUE of different wheat varieties under graded nitrogen doses during the winter seasons of 2022-2023 and 2023-2024. The study revealed that the variety PBW 826 demonstrated superior performance by applying 210 kg N/ha, exhibiting higher normalized difference vegetation index (NDVI) and chlorophyll content indices, along with lower flavonoid levels. PBW 826 also produced the highest biomass (14,506 kg/ha), grain yield (6,066 kg/ha), and straw yield, with a 17.5% and 20.3% increase in grain yield compared to other varieties. The NUE for PBW 826 was highest (38.1%) at 30 kg N/ha. While biomass, grain yield, and straw yield increased with nitrogen application up to 150 kg/ha, no significant differences were observed beyond this level. NUE metrics, including partial factor productivity and nitrogen harvest index, improved up to 150 kg N/ha but declined with further nitrogen increases. The study concludes that optimizing nitrogen levels up to 150 kg/ha enhances wheat productivity and efficiency, while excessive nitrogen application diminishes these benefits. Additionally, understanding the interaction between varieties and nitrogen levels for yield and NUE can help farmers select the best variety at the lowest nitrogen input, maximizing both profitability and sustainability.

In this paper, the method for extracting equivalent circuit parameters for small-signal operation and the modified Angelov model parameters used for the I-V model of a 0.25 µm indigenous large periphery (10 × 175 µm) GaN HEMT device has been described. The small-signal parameter extraction methodology is based on passive pinch-off S-parameter measurement which is used for getting the starting values of extrinsic elements and then optimizes them to minimize the objective function. For the DC I-V model, curve fitting of the measured I-V data was used for the extraction of model parameters. The accuracy of model was verified by S-parameter matching and I-V matching between the model and the measured data.