Abstract In coffee (Coffea arabica L.), vegetative and reproductive growth occur simultaneously, creating strong competition for assimilates and constraining biomass allocation. Although fruits are the dominant sink, quantitative relationships between fruit load, vegetative growth, and harvest index (HI) remain poorly understood in perennial crops. We evaluated how fruit load regulates vegetative biomass accumulation, yield, and HI in field-grown coffee trees and proposed a practical framework to quantify biomass partitioning under contrasting reproductive demand. Three field experiments were conducted in southeastern Brazil over two growing seasons, where six fruit load levels (100%, 80%, 60%, 40%, 20%, and 0%) were manually imposed at the pinhead stage. Vegetative growth, leaf area, fruit yield, and aboveground biomass were measured. Increasing fruit load markedly reduced vegetative biomass by up to 79% compared with trees without fruits, suppressing leaf and branch development. Each kilogram of fruit dry matter produced was associated with a reduction of approximately 392 g of vegetative dry matter. HI increased with fruit load but stabilized at approximately 0.75 once fruit dry yield exceeded 1.4 kg tree −1 , indicating a physiological upper limit to reproductive allocation. These values, based on branch and leaf biomass, represent an upper estimate because whole-plant HI including roots and perennial woody tissue would be lower. The plateau likely reflects the need to maintain sufficient vegetative structure to sustain photosynthesis and assimilate transport despite high reproductive demand. These results clarify source-sink regulation in coffee and provide a robust framework for estimating biomass partitioning with applications in crop management and growth modelling.
Abstract Simiao rice, a high-quality indica variety widely cultivated in South China’s double rice cropping systems is vital for regional food security. However, the seasonal and varietal responses of its grain yield and quality to nitrogen (N) application remain insufficiently understood. This two-year (2022–2023) field experiment investigated three N application rates (N1: 105, N2: 135, N3: 165 kg ha −1 ) on multiple Simiao rice varieties, focusing on grain yield, milling, and appearance qualities. Higher N rates had no significant effect on early rice yield, but significantly increased late rice yield. The two-year average yield of N1 (5.71 Mg ha −1 ) was lower than N2 (6.23 Mg ha −1 ) and N3 (6.51 Mg ha −1 ) ( P < 0.05), attributed to increased total spikelets. For early rice, the two-year average head rice rate increased with N (41.4% for N1, 42.6% for N2, 43.7% for N3), mainly driven by improved quality in high-chalkiness varieties (MXZ2, GXYLSM, HFYYX, and QXY19X). These varieties exhibited reduced chalky grain rate (26.0–20.8%) and chalkiness (10.0–7.2%) with increasing N, while low-chalkiness varieties (19X, TX812, XZXSM, and XXZ) showed no significant changes. For late rice, N rates did not affect milling or appearance quality. This study clarified that N application exerts distinct seasonal and varietal effects on dual-use Simiao rice: increasing N application significantly enhances late rice grain yield while improving early rice milling and appearance quality. These findings provide critical insights into tailored N management for high-quality and high-yield Simiao rice production in South China’s double cropping system.
Summary Aeroponics has emerged as a strategic technology for producing high-quality seed potatoes; however, its scientific basis remains methodologically fragmented. This systematic and critical review analyses 29 experimental studies published between 2021 and 2025, selected using a PRISMA-based protocol, to evaluate methodological consistency, genetic representativeness, and transparency in the presentation of results in aeroponic potato research. The results reveal a strong geographic concentration (mainly in India and China) and limited inclusion of key potato-producing regions such as the Andes and Western Europe. Although more than 80 cultivars are reported, their distribution is highly skewed towards a few breeding programmes, limiting their global applicability. High variability was identified in the plant material, environmental conditions, system configuration, nutrient solution composition, and agronomic variables evaluated, frequently reported with inconsistent units and a lack of methodological detail. These limitations reduce reproducibility and hinder comparability between studies. This review highlights the urgent need to establish minimum reporting standards and proposes a structured framework to improve experimental consistency. Moving towards methodological harmonization is essential to enable robust data integration and consolidate aeroponics as a reliable technology for global potato seed production systems.
Summary Intercropping cereals and legumes may enhance system productivity by simultaneously producing grain for human consumption and crop residues for livestock feed. This study evaluated the effects of maize ( Zea mays ) intercropped with cowpea ( Vigna unguiculata ) or mucuna ( Mucuna pruriens ) on soil moisture dynamics, grain and forage yields, and household food and feed self-sufficiency under varying rainfall conditions. The experiment was conducted on five farms in Mutoko District, Zimbabwe, during the 2021/22 and 2022/23 growing seasons using a Randomized Complete Block Design with five treatments: sole maize, sole cowpea, sole mucuna, maize–cowpea intercropping, and maize–mucuna intercropping. Soil moisture was measured biweekly to 1.8 m depth. Each season, experimental sites were classified according to seasonal rainfall as dry (<450 mm), average (450–600 mm), or wet seasons (>600 mm).Intercropping performance was influenced by rainfall. Sole mucuna utilized more soil moisture than other cropping systems. In dry and average seasons, sole maize yielded 1,812 kg ha −1 of grain, 103% more than maize intercrops, and met annual household maize requirements. In wet seasons, maize–cowpea intercropping produced higher maize grain yields (3,273 kg ha −1 ) than sole maize (2,372 kg ha −1 ), with a land equivalent ratio of 2.18. Mid-season dry spells reduced grain yields across treatments but had limited effects on stover production. During wet seasons, mucuna-based systems generated the highest forage and crude protein yields, sufficient to feed five cattle during the dry season. These findings highlight that maize–legume intercropping can enhance food and feed production during relatively wet seasons
Abstract Effective soil nutrient management remains a critical determinant of agricultural profitability among smallholder farmers. This research evaluates the economic viability of fertilizer trials for teff and sorghum crops under different landscape positions in the dryland areas of northeastern Ethiopia. The study employed a randomized complete block design (RCBD) comprising nine treatments across three districts. Data from 855 experimental plots were analysed using a linear mixed-effects model (LMEM) across the slope gradients of foot slope, mid slopes, and hill slopes. Partial budget analysis, value-to-cost ratios (VCRs), and sensitivity analysis were employed to evaluate the economic feasibility of nutrients. The result from the LMEM revealed that fertilizer treatments, crop type, and slope position significantly affect net benefits. The results also showed that profitability declined progressively from the foot slope to the mid slope and further to the hill slope. The mixed model results indicated that the NP fertilizer has substantially increased net benefits relative to other treatments. Moreover, the partial budget, VCR, and sensitivity analyses also confirmed that NP fertilizer produced the highest economic return for both crops. A sensitivity analysis further confirmed the robustness of the NP fertilizer under the price fluctuation scenarios of inputs (fertilizer and both crops). Therefore, the NP is an economically viable fertilizer for both teff and sorghum producers. Strategic soil and nutrient management practices tailored to different landscape positions will further enhance farm profitability in the study areas.
