Abstract Seed quality critically influences bread wheat ( Triticum aestivum L.) productivity and food security in Ethiopia. Limited information exists on how farmers' seed recycling practices and lot level variations affect seed quality. Therefore, this study was conducted to assess the quality characteristics of bread wheat seeds used by farmers in Debre Elias district of East Gojjam Zone, Ethiopia. We analyzed 20 seed lots—comprising 15 farmer‐recycled samples (spanning 1–3 years of recycling, with five lots per year category) and five enterprise lots serving as fresh benchmarks. The results revealed that recycling frequency significantly ( p < 0.001) affected physical purity components, germination performance, and dead seed proportions. The lowest purity (99.21%) was recorded from the 3‐year recycled samples. Highly significant ( p < 0.001) differences were also observed among individual seed lots in analytical purity and inert matter composition. Significant ( p < 0.001) variations in seed germination and vigor performance were also observed among individual seed lots. These laboratory findings indicate that recycling duration was associated with declining seed quality, while lot‐to‐lot variation was also substantial. Lot‐level quality assessment may therefore complement recycling history when evaluating farmer‐saved seed, though field validation is required before these results can inform seed replacement decisions.
Abstract Carrot ( Daucus carota L.) is a nutritionally vital root vegetable, yet productivity in Ethiopia's Sankura District remains constrained by suboptimal agronomic practices. This study evaluated the interactive effects of variety, plant spacing, and nitrogen (N) fertilization on carrot growth, yield, and nitrogen use efficiency (NUE) components: partial factor productivity (PFP), agronomic efficiency (AE), physiological efficiency, and recovery efficiency. A 2 × 4 × 3 factorial randomized complete block design with three replications tested two varieties (Nantes and Nantes‐Improved), four intra‐row spacings (4, 6, 8, and 10 cm), and three N rates (0, 69, and 138 kg N ha − 1 ) across two cropping years (2023 and 2024). Nantes‐Improved consistently outperformed Nantes in yield and NUE parameters. The combination of 6 cm spacing with 69 kg N ha − 1 produced the highest marketable yield (23.7 t ha − 1 ) and net economic benefit (292,411 ETB [Ethiopian Birr] ha − 1 ), while the interaction between narrow spacing (4 cm) and high N (138 kg N ha − 1 ) increased unmarketable yields due to competition‐induced deformities. Tissue N (nitrogen concentration) content and AE peaked at 69 kg N ha − 1 , beyond which diminishing returns occurred. PFP was highest (38.1 kg kg − 1 N) at the moderate N rate, indicating optimal N utilization. Correlation analysis revealed a trade‐off between shoot vigor and root development, with plant height positively correlating with yield but negatively affecting root dimensions. This study provides the first comprehensive assessment of variety × spacing × N interactions for carrots in Ethiopian highland conditions, demonstrating that adopting Nantes‐Improved at 6 cm spacing with 69 kg N ha − 1 optimizes productivity, quality, and profitability while improving NUE. These findings offer actionable recommendations for smallholder farmers and extension services to enhance sustainable carrot production.
Abstract Soil harbors diverse microbial communities that are fundamental to soil health and agricultural sustainability. Despite their ecological and agronomic importance, these communities remain underutilized as biological resources for improving crop production. With increasing concern over future food security under population growth, land constraints, and environmental degradation, biologically informed alternatives to input‐intensive agriculture are urgently needed. Soil microorganisms contribute to agricultural productivity through nutrient transformation, mineral solubilization, phytohormone production, metabolite secretion, and interactions that influence soil structure and plant performance. However, translating this potential into sustainable farming requires a clearer understanding of microbial taxonomy, ecological function, depth‐specific distribution, and plant–soil–microbe interactions. This review synthesizes current knowledge on soil microbial diversity and highlights the roles of microbial communities in metabolite secretion, nutrient dynamics, and soil ecosystem functioning. We also discuss how these processes can be better harnessed to support sustainable agriculture. By integrating recent literature on microbial diversity, functional traits, and soil‐profile heterogeneity, this review emphasizes both the opportunities and the current knowledge gaps in using soil microbiomes to strengthen agricultural resilience and long‐term soil health.
Abstract In semiarid western US dairy systems, field evidence remains limited on whether processed manure products can sustain silage corn ( Zea mays L.) productivity and improve soil health. A field experiment conducted in Logan, UT, during 2021–2022 compared compost, vermicompost, Sedron (a thermally and mechanically processed dairy manure), dissolved air flotation, mineral fertilizer, and unfertilized control for their effects on soil chemical properties, silage corn yield, forage quality, and soil health indicators. Amendments effects on soil pH and total carbon were limited, but the compost + vermicompost mixture produced the highest surface‐soil phosphorus and potassium concentrations of 35.6 and 241 mg kg −1 , respectively. Silage corn yield ranged from 21.5 to 27.8 Mg ha −1 in 2021 and 17.0 to 25.8 Mg ha −1 in 2022. The compost + vermicompost produced the highest yield of 25.8 Mg ha −1 in 2022 compared with 17.0 Mg ha −1 in the control. Sedron produced the highest crude protein and total digestible nutrients and the lowest acid detergent fiber (ADF), at 8.40%, 73.0%, and 21.1%, respectively. Compost increased soil infiltration to 1.83 cm h −1 compared with 0.62 cm h −1 in the control. Sedron maintained higher potentially mineralizable nitrogen (N) in the second year. Processed manure products did not consistently outperform compost or mineral fertilizer, but individual products improved specific responses. These materials may therefore be useful in silage corn systems for recycling manure nutrients while improving forage quality, infiltration, or N mineralization. Longer‐term studies are needed to determine whether these effects persist and lead to broader gains in soil health and nutrient‐use efficiency.
Abstract In the irrigated arid regions of Iraq, soil degradation and severe evaporative demand constrain legume productivity. Although ecological intensification using organic amendments is widely promoted, the specific mechanisms governing crop–weed–soil interactions remain poorly understood. A field experiment was conducted in Baghdad (spring‐summer 2025) using a split‐plot factorial design (3 × 3 factorial with three replications) to evaluate the individual and combined effects of wheat straw mulch (0, 5, 10 cm) and compost (1, 2, 3 t ha −1 ) on lima bean ( Phaseolus lunatus L.) performance and weed density. Mulch (10 cm) enhanced seed yield by 45.5% and markedly suppressed weed density. Increasing compost rates (up to 3 t ha −1 ) promoted vegetative growth and pod formation. The interaction between mulch and compost was trait‐dependent: no significant mulch × compost interaction was detected for seed and biological yields, whereas significant interactions were observed for harvest index, crude protein content, branch number, and weed density. The treatment combination of 10 cm mulch × 3 t ha −1 compost maximized seed protein (23.16%), and the combination of 1 t ha −1 compost + 10 cm mulch reduced weed density by 44% compared to the 3 t ha −1 compost + 0 cm mulch treatment. A logarithmic regression indicated a significant negative association between mid‐season weed density and seed yield ( R 2 = 0.44). Under the conditions of this study, coupling thick straw mulch with increasing compost rates altered resource partitioning into seed quality, offering a practical supplementary weed management option within fertilized arid agroecosystems.
