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A data-driven approach for devising and assessing precision nitrogen management strategies applied to wheat systems in India
No full textLimiting nitrogen pollution from crop production is essential for mitigating greenhouse gas emissions and protecting aquatic ecosystems while maintaining food security. Precision nitrogen management (PNM) provides a conceptual framework for achieving yield goals while maintaining nitrogen pollution within planetary boundaries by matching fertilizer rates to specific production conditions. Nevertheless, PNM strategies for smallholder contexts like India, a global nitrogen pollution hotspot, have proven costly to implement and are often ineffective. By combining survey data of production practices from 8705 wheat fields with digital soil mapping, we develop a novel PNM strategy that ‘learns from landscapes’ to generate and evaluate novel decision logic for nitrogen management. With this approach, ex-ante simulations indicate that reductions of 9% in nitrogen use and 16% in N2O emissions can be achieved without compromising yields, saving US$ 28 million per year in subsidies for the Indian state of Bihar alone. In contrast, conventional soil test-based recommendations may increase nitrogen use by 5% without corresponding yield gains. Our method that leverages large-n survey data and predictive modeling may provide a scalable pathway for PNM in similarly complex crop production environments where field and management heterogeneity is high
From genes to fields: Marker-assisted selection for nematode resistance in crops
No full textPlant-parasitic nematodes (PPNs) are one of the serious threats to agricultural production worldwide, causing enormous economic losses and posing a threat to food security. This review outlines a few important groups of PPNs, their economic losses, and current control approaches. Marker Assisted Selection (MAS) has been recognized as a precise and efficient approach for developing nematode-resistant cultivars and an environmentally friendly alternative to conventional control practices. Genome-Wide Association Studies (GWAS) thereby provide a way of identifying novel resistance loci and deciphering the genetic basis of resistance traits. MAS guided by validated GWAS results have therefore immense prospects for enhancing resistance breeding, reducing over-dependence on nematicides, and fostering healthy agricultural systems. Future efforts should focus on integrating molecular with field-based approaches to maximize benefits in the control of nematodes.1-1
Determinants of improved seed adoption and intensity in lentil farming: evidence from Terai region of Nepal
No full textThe prevailing dominance of the informal seed system and dramatically low seed replacement rate (SRR) are the potent evidence of poor adoption of improved lentil seed in Nepal. In this study, we used a logit model to identify the determinants of farmers' decisions regarding the adoption of improved lentil seed in Nepal. A total of 300 participants, selected using stratified random sampling, were interviewed using a pretested questionnaire. Focus group discussions and key informant interviews were also conducted. The empirical results showed that owned land (p <= .047), number of economically active household members (p <= .018), improved seed knowledge (p <= .001), training (p <= .045), technical assistance (p <= .005), demonstration visits (p <= .001) and subsidies (p <= .035) had a significantly positive effect on the adoption of improved lentil seed, while waterlogging low land (p <= .049) and seed cost (p <= .032) had a significantly negative effect. The level of recommended technology adoption by improved seed adopters was calculated using the adoption index. The low adoption index (0.38) revealed the underutilization of recommended lentil production technologies by the improved seed adopters. The proportion of land with improved seed and the rate of seed used were satisfactory, but fertilizer and pesticide use were dramatically lower than the recommended level. To facilitate the sustainable adoption of improved seed, the government must place emphasis on holistic and robust research and extension services, technical assistance and demonstration visits, along with the implementation of targeted subsidy programs
Farm production, marketing, and children's nutritional outcomes in rural Zambia
No full textDespite increasing agricultural productivity, malnutrition remains high among food producers in many developing countries. This study examines how the difference between agricultural household nutrition requirements and production kept for home consumption, the Nutritient deficiency from own production (NDOP), impacts children's height-for-age z-scores (HAZ) using a unique survey of 528 households in Zambia. The study also investigates the relationship between NDOP and market-bought nutrition and the role of intra-season price changes in nutrition. To address the endogeneity of NDOP, we use a control function approach. We find that NDOP is associated with lower HAZ. Both energy (calories) NDOP and nutrient-specific NDOP, resulting from underproduction relative to nutritional requirements and from selling more than surplus food crops, are negatively correlated with HAZ. This result suggests that higher productivity and market participation do not always lead to better nutrition. We also find that crop sales (commercialization) only benefit nutrition if the household only sells surplus output relative to its nutritional requirements. Finally, we also find that NDOP does not correlate with market food purchases, and that the seasonal price increases for cereals further dampens market food purchases. The findings highlight that policies promoting smallholder commercialisation may overlook detrimental nutrition trade-offs when own-production falls short of household needs. Accounting for post-harvest allocation of nutrients between own-consumption, sales, and purchases can help ensure agricultural interventions improve farmer livelihoods and child nutrition.283-30
EXGEP: a framework for predicting genotype-by-environment interactions using ensembles of explainable machine-learning models
No full textPhenotypic variation results from the combination of genotype, the environment, and their interaction. The ability to quantify the relative contributions of genetic and environmental factors to complex traits can help in breeding crops with superior adaptability for growth in varied environments. Here, we developed and extensively evaluated the performance of an explainable machine-learning framework named explainable genotype-by-environment interactions prediction (EXGEP) to accurately predict the grain yield in crops. To assess the performance of EXGEP, we applied it to a dataset comprising 70 693 phenotypic records of grain yield traits for 3793 hybrids (also including both genotype and environmental condition data). When used with four different combinations of genotypes and environmental data, EXGEP exceeded the yield prediction performance of the classic model Bayesian ridge regression model by 17.37%-42.35%. Moreover, EXGEP incorporates SHapley Additive exPlanations values that can uncover complex nonlinear relationships between genotype and environment and identify key features, and their interactions, that provide the main contributions to model performance, thus enhancing our understanding of genotype-by-environment interactions. Additionally, data from a series of tests support that EXGEP exhibits superior performance in terms of prediction accuracy and explainability. Our development of EXGEP and comparisons of it against alternative models provides valuable insights into methods for accurately predicting complex traits in multiple environments
Motivations and incentives for mechanization in Zambia: a mixed-methods analysis
No full textSmallholder farmers in Zambia face low agricultural productivity, and while tractor mechanization offers a solution, adoption rates remain low. The contextual factors driving this low uptake, including farmers’ preferences for different ownership and financing models, are not well understood. This study uses a mixed-methods approach, including surveys with 208 farmers, 18 focus group discussions (FGDs) and 28 key informant interviews (KIIs) across three districts in Zambia to examine these issues. The analysis shows that the motivations for tractor ownership are centred around both productivity enhancement and income generation through service provision, with farmers valuing tractors’ ability to improve operational timeliness given narrowing planting windows. The results reveal a clear divergence in ownership preferences. Individual ownership is favoured by male farmers and those in more mechanized districts seeking operational autonomy, while group ownership is preferred by female farmers and those in less-mechanized areas for its cost-sharing and risk-management benefits. In terms of incentives for ownership, risk-contingent credit (RCC), particularly when bundled with repair insurance, emerges as the most desirable incentive for encouraging tractor ownership. This highlights the need to de-risk mechanization investments. Key barriers to adoption include high maintenance costs, poor access to spare parts and the financial strains due to social obligations. These results demonstrate that a ‘one-size-fits-all’ approach to promoting mechanization is ineffective. Instead, successful interventions must be flexible, gender-responsive and tailored to the local context. Such an approach would likely increase ownership and improve livelihoods
Impact pathways for the adoption of biological nitrification inhibition (BNI) wheat: a scoping study
No full textThis scoping study assesses the institutional, systemic, and market readiness for introducing Biological Nitrification Inhibition (BNI) wheat in Kenya, Ethiopia, and India. It applies CIMMYT’s Scaling for Impact diagnostic framework to identify technical, regulatory, and behavioral constraints to BNI scaling. The study draws on a systematic review of seed systems and farmer typology; analysis of nationally representative household surveys; and stakeholder consultations with 75 experts.64 page
Mitigating micro-nutrient deficiencies in the diets of rural farm households on the south-central coast of Bangladesh: What roles do the markets and homestead play?
No full textThis study explores the roles of market access and on-farm production in ensuring adequate micronutrient consumption among households in coastal Bangladesh. First, the study employed a 7-day weighed food record method, where respondents documented all food items consumed daily at the household level. These food items were then converted into their corresponding nutritional values to estimate the intake of key nutrients, including protein, crude fiber, fat, calcium, potassium, iron, magnesium, phosphorus, zinc, vitamin A, vitamin C, niacin, riboflavin, thiamin, and folate. Household nutritional requirements were calculated based on the Bangladesh Recommended Dietary Allowances (RDAs), accounting for the age and sex of household members. Nutrient adequacy was assessed by comparing actual nutrient intake against these RDA benchmarks. Second, the study analyzed the determinants of nutrient adequacy using truncated regression models, incorporating relevant socioeconomic and demographic variables. The findings reveal a stark contrast: households meeting RDAs predominantly source their nutrients from markets, highlighting the significance of market accessibility and financial capacity. In contrast, households failing to meet RDAs depend heavily on homesteads, which often lacks dietary diversity and nutrient density. Moreover, the food sources vary depending on the micronutrients in question. Additionally, the study identifies key socio-economic vulnerabilities: younger household heads, often prioritizing crop sales, require greater nutritional awareness; female-headed households face unique barriers to adequate nutrient intake; and households burdened by credit constraints experience reduced consumption of critical nutrients like folate and crude fiber. To address these challenges, the study advocates target group differentiated policy approaches, promoting nutrient-dense crop production, subsidized food safety nets, market-based interventions, credit restructuring, and homestead gardening programs that can attain and long-term nutritional resilience in coastal Bangladesh
