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Combating aflatoxin contamination by combining biocontrol application and adapted maize germplasm in northeastern and southeastern Mexico
No full textMaize is highly vulnerable to aflatoxin (AF) contamination caused by fungi from the Aspergillus section Flavi, with deficiencies in post-harvest management practices further exacerbating AF levels. Due to their carcinogenic properties, AFs pose significant health risks. Biological control using non-aflatoxigenic A. flavus isolates has been effective for over 25 years in the USA, with two formulations being commercially available. However, no such products have been developed yet for use in Mexico. This study evaluated the effectiveness of AF36-Prevail®, a non-aflatoxigenic strain from Arizona, for reducing aflatoxin contamination in Mexico. Over four years (2019–2022), we assessed its impact alongside regionally adapted maize germplasm in northeastern and southeastern Mexico. We analyzed a total of 1,479 grain samples, with 887 from biocontrol-treated fields, and 592 from untreated fields across 69 sites in Tamaulipas and Campeche. Treated fields showed 59.0 % to 89.9 % reductions in AF content compared to untreated fields, and higher ear rot was observed in untreated fields. Correlation coefficients between ear rot and AF content were r = 0.08 for Campeche and r = 0.36 for Tamaulipas. Significant differences (p ≤ 0.001) were noted between years and hybrids for both yields and AF levels. Three hybrids in Tamaulipas and four in Campeche demonstrated better adaptation, higher yields, and lower AF levels (< 20 ppb). This research underscores the potential for safer maize production in Mexico, particularly when combining biocontrol strain application with adapted germplasm
The role of information and communication technologies-based extension in agriculture: application, opportunities and challenges
No full textLimited access to information about new technologies is a major barrier to agricultural productivity. To bridge this information gap, agricultural extension services increasingly use Information and Communication Technologies (ICTs) to provide timely and actionable information to farmers. This systematic review analyses evidence from 49 studies examining the impact of ICT interventions including mobile apps, SMS messaging, educational videos, and voice calling services on awareness, agricultural practices adoption, yields, and income. The review reveals that 76% of studies reported increased adoption of good agricultural practices, 60% demonstrated improved awareness, 74% indicated higher yields, and 68% observed enhanced incomes. Cereals, particularly maize, were the most studied crops, featuring in 52% of the studies. The success of the ICT interventions depends on well-designed messaging, adequate user training, and integration with complementary interventions. While ICTs demonstrate substantial potential to advance agricultural development outcomes, their success requires customization to local contexts, capacities, and cropping systems
Linking weather and climate information services (WCIS) to Climate-Smart Agriculture (CSA) practices
No full textObjective(s): This study synthesises existing knowledge on the linkages between Weather and Climate Information Services (WCIS) and Climate-Smart Agriculture (CSA) practices. Specifically, it addresses the following questions: (1) What is the current status of knowledge on WCIS and CSA in the global south, specifically the African continent?, (2) Are WCIS effectively tailored and linked to CSA practices and technologies to improve agricultural water management (AWM) amongst smallholder farmers?, and (3) How can linking WCIS and CSA facilitate the identification, appraisal and prioritization of regionally differentiated and context-specific climate-appropriate technologies and policies that enhance agricultural water management at various levels (field, farm, scheme, and catchment)? Methods: The study used the Preferred Reporting Items for Systematic and Meta-Analysis Protocol (PRISMA-P) guidelines. It involved the search of the Scopus and Web of Science databases for peer-reviewed articles, books, and grey literature focussed on the global south. Results: The results revealed that seasonal forecasts were the main WCIS available to farmers who utilised them to plan predominantly for irrigation and water harvesting activities. Daily forecasts were linked to practices such as irrigation. The study also revealed that temperature and rainfall (amount and distribution) were predominantly disseminated to farmers through extension services. The dominant CSA practices used by farmers were carbon-smart (e.g., composting), water-smart practices (improved varieties, irrigation, RWH), weather-smart practices (IPM & crop insurance), and nitrogen-smart practices (organic fertiliser, crop diversification). Advisories on carbon-smart practices generally aligned closely with the start and end of rainfall information, while the water-smart practices were corroborated with the rainfall onset, end of rainfall season, and rainfall intensity. Weather smart practices were strongly linked to drought, temperature, and rainfall distribution, whereas nitrogen smart practices were linked with the end of rainfall and temperature. Conclusions: The study concluded that distinct linkages exist between WCIS and various CSA categories. The study argues that increasing access to WCIS can facilitate the adoption and scaling of CSA practices
Tied ridges compensate for crop residue removal in conservation agriculture
No full textSoil cover with crop residues can increase soil health and water availability, leading to improved production under dryland conditions, but crop residues can be in high demand as animal fodder. In a 21-year-long experiment in central Mexico, we compared the yield and profitability of wheat (Triticum aestivum L.) and maize (Zea mays L.) on conventional tilled beds to permanent beds with varying residue levels and evaluated whether tied ridges could offset the negative effects of residue removal. The maize and wheat grain yields from permanent beds with full residue retention were 2.1 Mg ha−1 (30%) and 0.5 Mg ha−1 (13%) greater, respectively, than the yields from conventional tilled beds. Permanent beds with full residue retention increased yields by over 10% compared to beds with partial retention, while partial residue retention with tied ridges achieved similar yields to full retention. Adding tied ridges to permanent beds without residues increased yields by 20%. Yield stability did not differ among treatments. Permanent beds with full residue retention generated six times higher net income compared with beds with conventional tillage, while the treatment that involved removing all residues and adding tied ridges doubled the profit generated by the treatment using full residue retention. Overall, permanent beds with partial residue retention improve yields, and tied ridges could mitigate some of the adverse effects of partial residue removal, making partial retention with tied ridges a more profitable system, contingent on the residue market
Comparing soil microbial diversity in smallholder plantain backyard gardens and main farms in Western and Central Africa
No full textIn sub-Saharan Africa (SSA), plantains (Musa spp.) are a staple crop and a vital source of income for smallholder farmers. Despite their importance, the microbial diversity of soils in plantain-growing agroecologies remains poorly understood-particularly how it may influence plant performance and resilience through soil-plant interactions. In this study, we used Illumina MiSeq-based 16S rDNA sequencing to characterize bacterial communities in the rhizosphere of plantains cultivated under two distinct agroecological settings: Backyard gardens and main farms. Analyses of alpha and beta diversity (Sobs, Chao1, ACE, Shannon-Wiener, and Simpson indices; P < 0.05) revealed significant differences in species richness and community structure between the two agroecologies. Actinobacteria (55%) emerged as the dominant phylum, followed by Proteobacteria (21%) and Acidobacteria (15%). Beneficial genera such as Bacillus, Streptomyces, Bradyrhizobium, and Paenibacillus were also detected. Functional predictions based on COG and KEGG databases indicated notable differences in microbial functional potential between the two settings. These results suggest that agroecological context and habitat type strongly influence rhizosphere microbial diversity, with important implications for enhancing plant-microbe interactions and supporting crop resilience in SSA's resource-limited smallholder systems
Site-specific nutrient management for rice in Nepal: Estimating indigenous nutrient supply, improving fertilizer recommendations, and enhancing yield in the Terai Region
No full textTo address declining soil fertility and stagnating rice yields in farmers' fields, this study evaluated 4-R (right-source, right-rate, right-time, right-place) principles based site-specific nutrient management (SSNM) strategies and varying potassium application rates in the western foothills of Nepal. Field experiments conducted between 2011–2013 and2022–2023 quantified the indigenous nutrient supply (INS) and evaluated the performance of SSNM strategies. These strategies incorporated real-time nitrogen management using leaf color charts (LCC), soil plant analysis development (SPAD), and Nutrient Expert (decision support tool) along with varying K rates on K-deficient soils to evaluate impacts on yield, nutrient uptake, and nutrient-use efficiencies. The results revealed significant spatial variability in soil nutrient levels, with nitrogen (N) being most limiting, followed by phosphorus (P) and K, with mean INS of 53, 29, and 84 kg N, P2O5, and K2O ha-1. SSNM increased rice yield by 36 % (1.68 t ha−1) over traditional farmer practices and by 12 % over blanket recommendations, while reducing N and P2O5 inputs by 4 % and 28 %, respectively. Potassium application needed to be increased by 80 % to prevent soil depletion, indicating that the current K2O recommendationshould be doubled to 80 kg ha−1 to sustain yield and nutrient uptake. LCC-based N increased yield by 4 % without additional N, while SPAD-based N application further saved 8 kg N ha−1. Farmers' current practices yielded 4.69 t ha−1 reflecting a 33 % yield gap compared to attainable yield (7.0 t ha−1). The combine use of LCC-based N with SSNM and Nutrient Expert achieved yields of 6.61 t ha−1, reduced yield gap just to 5.5 %. Overall, SSNM proved to be a robust strategy for addressing nutrient deficiencies, and improving fertilizer recommendation and use effeciencies in rice, delivering agronomic, economic, and environmental benefits to smallholder systems. However, its wider adoption requires targeted farmers’ training and strengthened extension support
Phenotypic characterization and genetic diversity of sweet corn inbred lines
No full textAn experiment was conducted to evaluate genetic diversity among 23 sweet corn (Zea mays L. saccharata) inbred lines during rabi 2024 at the Main Agriculture Research Station, University of Agricultural Sciences, Raichur, Karnataka. The sweet corn inbred lines were evaluated in a randomized complete block design with two replications. Observations were recorded on key traits and data were analyzed for variability, clustering and principal component analysis (PCA). Analysis of variance revealed significant differences among inbreds, indicating the presence of substantial genetic variability. High genotypic and phenotypic coefficients of variation were observed for kernels per row and kernel rows per cob, while seed weight showed narrow variability. High heritability coupled with high genetic advance for kernels per row and kernel rows per cob suggested the predominance of additive gene action, highlighting the effectiveness of direct selection. Cluster analysis grouped the sweet corn inbreds into three distinct clusters, with maximum inter-cluster divergence observed between Cluster I and Cluster III, providing greater scope for heterotic hybrid development. Cluster mean analysis revealed trait-specific superiority i.e. Cluster I for yield traits, Cluster II for sweetness and Cluster III for kernel compactness. PCA indicated that the first three components accounted for 79.77% of total variation, with cob yield traits contributing predominantly, followed by phenological and quality traits. Promising divergent sweet corn genotypes such as SC-22, SC-30, SC-14 and SC-20 were identified as potential parents. The identified heterotic groups provide a strong genetic basis for parental selection and heterosis exploitation in sweet corn breeding.350-36
TaIAA10-6D orchestrates processing quality and grain yield by modulating glutenin/gliadin ratio and plant morphogenesis in wheat
No full textHigh molecular weight glutenin subunits (HMW-GS), major components of seed storage proteins in wheat, have large effects on processing quality. GLU-1 genes encode HMW-GS and their expression is mainly controlled at the transcriptional level by interactions between cis-regulatory elements and transcription factors. We previously identified an Aux/IAA transcription factor TaIAA10-6D that bound to a conserved cis-regulatory module CCRM1-1, the most essential conserved cis-regulatory module in GLU-1. Here, we confirmed the binding of TaIAA10-6D to CCRM1-1 using yeast one hybrid and dual-luciferase reporter assays. The enhanced expression of TaIAA10-6D suppressed glutenin accumulation and increased gliadin content. Dynamic transcriptome analyses revealed that TaIAA10-6D overexpression down-regulated glutenin and gliadin genes during an early stage of grain filling, but up-regulated gliadin genes during a late stage probably by endoplasmic reticulum stress, accounting for its effect on the trade-off between glutenin and gliadin. Rheological property and processing quality assays showed that TaIAA10-6D overproduction reduced stabilization time and bread quality, but enhanced cookie quality. Overexpression of TaIAA10-6D also reduced plant height, leaf size, kernel number and grain yield. We identified two major haplotypes of TaIAA10-6D, Hap I and Hap II, and developed a breeding-friendly diagnostic marker. Hap I conferred higher expression of TaIAA10-6D and concomitantly reduced plant height and kernel number, but had little effect on grain yield, contributing to lodging resistance without yield penalty. Hap I was subjected to positive selection in breeding. The findings provide a useful gene for wheat improvement and broaden insights into the regulatory machinery underpinning auxin-mediated quality formation, plant morphogenesis and yield gain.1460-146
Geospatial land suitability mapping to support scale-appropriate mechanization in Nepal
No full text20 page
High-throughput phenotyping discovers new stable loci controlling senescence rate in bread wheat
No full textNon-destructive time-series assessment of chlorophyll content in flag-leaf (FLC) accurately mimics the senescence rate and the identification of genetic loci associated with senescence provides valuable knowledge to improve yield stability under stressed environments. In this study, we employed both unmanned aerial vehicles (UAVs) equipped with red-green-blue (RGB) camera and ground-based SPAD-502 instrument to conduct temporal phenotyping of senescence. A total of 262 recombinant inbred lines derived from the cross of Zhongmai 578/ Jimai 22 were evaluated for senescence-related traits across three environments, spanning from heading to 35 d post-anthesis. The manual senescence rate (MSR) was quantified using the FLC and the active accumulated temperature, and UAV derived vegetation index were utilized to assess the stay-green rate (USG) facilitating the identification of senescent and stay-green lines. Results indicated that higher senescence rates significantly impacted grain yield, primarily by influencing thousand-kernel weight, and plant height. Quantitative trait loci (QTL) mapping for FLC, USG, and MSR using the 50K SNP array identified 38 stable loci associated with RGB-based vegetation indices and senescence-related traits: among which 19 loci related to senescence traits from UAV and FLC were consistently detected across at least two growth stages, with nine loci likely representing novel QTL. This study highlights the potential of UAV-based high-throughput phenotyping and phenology in identifying critical loci associated with senescence rates in wheat, validating the relationship between senescence rates and yield-related traits in wheat, offering valuable opportunities for gene discovery and significant applications in breeding programs.1168-117