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Lr34/Yr18/Sr57/Pm38 confers broad-spectrum resistance to fungal diseases via transport of sinapyl alcohol for cell wall lignification in wheat
No full textThe widely recognized pleiotropic adult plant resistance gene Lr34 encodes an ATP-binding cassette transporter and plays an important role in breeding wheat for enhanced resistance to multiple fungal diseases. Despite its significance, the mechanisms underlying Lr34-mediated pathogen defense remain largely unknown. Our study demonstrates that wheat lines carrying the Lr34res allele exhibit thicker cell walls and enhanced resistance to fungal penetration compared to those without Lr34res. Transcriptome and metabolite profiling revealed that the lignin biosynthetic pathway is suppressed in lr34 mutants, indicating a disruption in cell wall lignification. Additionally, we discovered that lr34 mutant lines are hypersensitive to sinapyl alcohol, a major monolignol crucial for cell wall lignification. Yeast accumulation and efflux assays confirmed that the LR34 protein functions as a sinapyl alcohol transporter. Both genetic and virus-induced gene silencing experiments demonstrated that the disease resistance conferred by Lr34 can be enhanced by incorporating the TaCOMT-3B gene, which is responsible for the biosynthesis of sinapyl alcohol. Collectively, our findings provide novel insights into the role of Lr34 in disease resistance through mediating sinapyl alcohol transport and cell wall deposition, and highlight the synergistic effect of TaCOMT-3B and Lr34 against multiple fungal pathogens by mediating cell wall lignification in adult wheat plants
What adults and adolescents are eating in rural South Asia (Webinar session 11)
No full textTransforming Agrifood Systems in South Asia (TAFSSA), a CGIAR Initiative, hosted a webinar on ‘What are people eating in South Asia: Evidence from district assessment in Bangladesh, India and Nepal’, on June 6, 2024, from 4:00 pm to 5:00 pm IST. This is part of TAFSSA’s 2024 webinar series to highlight the research findings based on a comprehensive sub-national agrifood systems assessment conducted in early 2023 in rural areas of five districts across Bangladesh, India and Nepal.Esha SarswatTimothy J. KrupnikSamuel ScottSharvari PatwardhanArchana KonapurAvinash Kishore1:08:5
Post-intervention outcomes in farmer's behaviour and crop diversification in Chapainawabganj, Bangladesh
No full textCrop production is predominantly rice-centric in Bangladesh and, although economically rational, is risky and arguably unsustainable (1). In response, crop diversification emerged as an important strategy for achieving sustainable agriculture in Bangladesh (2). On-farm trials evaluated new cropping patterns in the Chapainawabganj district and promoted crop diversification among smallholder farmers. This brief summarizes the results from post-intervention outcomes in farmer behavior, covering a) preferred cropping patterns among farmers, b) perceived benefits, challenges, and transaction costs of crop diversification, and c) market awareness among trial farmers. Data were collected through face-to-face surveys involving on-farm trail farmers in the Chapainawabganj district.23 page
Testcross performance and combining ability of early-medium maturing quality protein maize inbred lines in Eastern and Southern Africa
No full textLimited commercial quality protein maize (QPM) varieties with low grain yield potential are currently grown in Eastern and Southern Africa (ESA). This study was conducted to (i) assess the performance of single-cross QPM hybrids that were developed from elite inbred lines using line-by-tester mating design and (ii) estimate the general (GCA) and specific (SCA) combining ability of the QPM inbred lines for grain yield, agronomic and protein quality traits. One hundred and six testcrosses and four checks were evaluated across six environments in ESA during 2015 and 2016. Significant variations (P ≤ 0.01) were observed among environments, genotypes and genotype by environment interaction (GEI) for most traits evaluated. Hybrids H80 and H104 were the highest-yielding, most desirable, and stable QPM hybrids. Combining ability analysis showed both additive and non-additive gene effects to be important in the inheritance of grain yield. Additive effects were more important for agronomic and protein quality traits. Inbred lines L19 and L20 depicted desirable GCA effects for grain yield. Various other inbred lines with favorable GCA effects for agronomic traits, endosperm modification, and protein quality traits were identified. These inbred lines could be utilized for breeding desirable QPM cultivars. The QPM hybrids identified in this study could be commercialized after on-farm verification to replace the low-yielding QPM hybrids grown in ESA
Univariate and multivariate genomic prediction for agronomic traits in durum wheat under two field conditions
No full textGenomic prediction (GP) has been evaluated in durum wheat breeding programs for several years, but prediction accuracy (PA) remains insufficient for some traits. Recently, multivariate (MV) analysis has gained much attention due to its potential to significantly improve PA. In this study, PA was evaluated for several agronomic traits using a univariate (UV) model in durum wheat, subsequently, different multivariate genomic prediction models were performed to attempt to increase PA. The panel was phenotyped for 10 agronomic traits over two consecutive crop seasons and under two different field conditions: high nitrogen and well-watered (HNW), and low nitrogen and rainfed (LNR). Multivariate GP was implemented using two cross-validation (CV) schemes: MV-CV1, testing the model for each target trait using only the markers, and MV-CV2, testing the model for each target trait using additional phenotypic information. These two MV-CVs were applied in two different analyses: modelling the same trait under both HNW and LNR conditions, and modelling grain yield together with the five most genetically correlated traits. PA for all traits in HNW was higher than LNR for the same trait, except for the trait yellow index. Among all traits, PA ranged from 0.34 (NDVI in LNR) to 0.74 (test weight in HNW). In modelling the same traits in both HNW and LNR, MV-CV1 produced improvements in PA up to 12.45% (NDVI in LNR) compared to the univariate model. By contrast, MV-CV2 increased PA up to 56.72% (thousand kernel weight in LNR). The MV-CV1 scheme did not improve PA for grain yield when it was modelled with the five most genetically correlated traits, whereas MV-CV2 significantly improved PA by up to ~18%. This study demonstrated that increases in prediction accuracy for agronomic traits can be achieved by modelling the same traits in two different field conditions using MV-CV2. In addition, the effectiveness of MV-CV2 was established when grain yield was modelled with additional correlated traits
Enhancing trader seed delivery models for sorghum and groundnuts: The case of Tanzania’s Kibaigwa Flour Supplies Ltd
No full text8 page
Value proposition for improved groundnut seed in Tanzania: Why and how to increase it
No full textThis brief explores the value proposition for farmers in Tanzania to invest in improved groundnut seed and the related implications for seed systems development. In late 2023–early 2024, we conducted 21 focus-group discussions and interviews with farmer groups, processors, traders, and seed producers. Our findings suggested that the current value proposition for improved seed was insufficient to encourage uptake at scale of improved seed. Farmers planted groundnut on poor soils, with little use of fertilizers or soil improvement conditioners. Brokers and traders purchased groundnuts in pods at the same price, regardless of size, color, or variety. While improved seed existed in limited volumes, the relatively high cost of the seed, combined with the lack of incentives for quality, meant that most farmers recycled their seed or purchased grain for use as seed. The success of future strategies to increase the impact from groundnut breeding hinges on farmers obtaining a higher value proposition from improved groundnut seed. The focus must be broader than seed systems development, encompassing long-term public and private sector investments in developing the peanut butter value chain, combined with investments in improving the agronomic conditions farmers face.7 page
Modelling the impact of different irrigation regimes and mulching on strawberry crop growth and water use in the arsenic-contaminated Bengal basin
No full textReplacement of water-intensive winter rice with strawberry (Fragaria x ananassa Duch.) may restrict groundwater extraction and improve water productivity and sustainability of agricultural production in the arsenic-contaminated Bengal basin. The potential of strawberry cultivation in terms of yield obtained and water use efficiency need to be evaluated under predominant soil types with mulch applications. Water-driven model AquaCrop was used to predict the canopy cover, soil water storage and above-ground biomass of strawberry in an arsenic-contaminated area in the Bengal basin. After successful calibration and validation over three seasons, AquaCrop was used over a range of management scenarios (nine drip-irrigation x three soil types x four mulch materials) to identify the best irrigation options for a drip-irrigated strawberry crop. The most appropriate irrigation of 176 mm for clay loam soil in lowland and 189 mm for sandy clay loam in medium land rice areas and the use of organic mulch from locally available jute agrotextile improved 1.4 times higher yield and 1.7 times higher water productivity than that of without mulch. Strawberry can be introduced as an alternative crop replacing rice in non-traditional upland and medium land areas of the arsenic-contaminated Bengal basin with 88% lower groundwater extraction load and better economic return to farmers
Bibliometric trends and insights into the potential of maize (Zea mays) under the framework of conservation agriculture
No full textIn spite of the detrimental effects of climate change and decreasing resource efficiency, maize farming is essential to the world’s food and nutritional security. With regard to sustainable maize farming in this environment, conservation agriculture (CA) offers a framework that holds promise in terms of low soil disturbance, perennial soil cover, and sustainable crop rotation. In order to acquire more profound information on the research advancements and publication patterns related to maize under CA scenarios, a bibliometric analysis was conducted. This involved utilizing René Descartes’s Discourse Framework to extract and screen 2587 documents spanning the years 2001 to 2023 from the Dimensions.ai database. The mapping showed that different stakeholders were becoming more interested in maize research under various CA pathways, with a greater emphasis on reaching the second sustainable development target, or “zero hunger”. The most influential journals were “Soil and Tillage Research” and “Field Crops Research”, with 131 and 85 papers with 6861 and 6186 citations, respectively. The performance analysis found “Christian L. Thierfelder” and “Mangi Lal Jat” as the eminent researchers in the areas of maize research under CA. Thus, the International Maize and Wheat Improvement Center (CIMMYT) and the Indian Agricultural Research Institute (IARI) were identified as the important institutions in conducting research pertaining to maize under CA systems, while the United States, India, and Mexico emerged as prominent countries with notable collaboration efforts for imparting research under the given scenarios. Three thematic clusters delineating keywords from three distinct sections—key drivers, objectives, and methodology—were identified through co-word analysis using word clouds, tree maps, and thematic networking of the keywords from the abstract and titles of screened publications. These thematic clusters highlighted the growing emphasis on region-specific studies under CA, particularly in sub-Saharan Africa and the Indo-Gangetic plain, to enhance the resilience of the agri-food system. Therefore, mapping maize’s potentialities within the CA framework has revealed the field’s dynamic nature and offers insightful information to researchers and policymakers that could help them plan future studies and cooperative initiatives aimed at boosting the productivity and sustainability of maize-based systems under the CA framework
Assessment of different frameworks for addressing climate change impact on crop production and water requirement
No full textVarious methodologies are used to estimate the impact of changing climatic factors, such as precipitation, temperature, and solar radiation, on crop production and water demand. In this study, the changes in rice yield, water demand, and crop phenology were estimated with varying CO2 concentration and an ensemble of general circulation models (GCMs), using a decision support system for agrotechnology transfer (DSSAT), a crop growth model. The measured CO2 concentration of 400 ppm from the Keeling curve, was used as the default CO2 concentration to estimate yield, water demand, and phenology. These outputs, obtained with the default concentration, were compared with the results from climate change scenarios' concentrations. Further, the outputs corresponding to the ensembled GCMs' climate data were obtained, and the results were compared with the ensembled crop model outputs simulated with each GCM. The yield was found to increase with the increase in CO2 concentration up to a certain threshold, whereas water demand and phenology were observed to decrease with the increase in CO2 concentration. The two approaches of the ensemble technique to obtain final outputs from DSSAT results did not show a large difference in the predictions