9 research outputs found

    Genome-Wide Association Mapping and Genomic Prediction of Anther Extrusion in CIMMYT Hybrid Wheat Breeding Program via Modeling Pedigree, Genomic Relationship, and Interaction With the Environment

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    Anther extrusion (AE) is the most important male floral trait for hybrid wheat seed production. AE is a complex quantitative trait that is difficult to phenotype reliably in field experiments not only due to high genotype-by-environment effects but also due to the short expression window in the field condition. In this study, we conducted a genome-wide association scan (GWAS) and explored the possibility of applying genomic prediction (GP) for AE in the CIMMYT hybrid wheat breeding program. An elite set of male lines (n = 603) were phenotype for anther count (AC) and anther visual score (VS) across three field experiments in 2017–2019 and genotyped with the 20K Infinitum is elect SNP array. GWAS produced five marker trait associations with small effects. For GP, the main effects of lines (L), environment (E), genomic (G) and pedigree relationships (A), and their interaction effects with environments were used to develop seven statistical models of incremental complexity. The base model used only L and E, whereas the most complex model included L, E, G, A, and G × E and A × E. These models were evaluated in three cross-validation scenarios (CV0, CV1, and CV2). In cross-validation CV0, data from two environments were used to predict an untested environment; in random cross-validation CV1, the test set was never evaluated in any environment; and in CV2, the genotypes in the test set were evaluated in only a subset of environments. The prediction accuracies ranged from −0.03 to 0.74 for AC and −0.01 to 0.54 for VS across different models and CV schemes. For both traits, the highest prediction accuracies with low variance were observed in CV2, and inclusion of the interaction effects increased prediction accuracy for AC only. In CV0, the prediction accuracy was 0.73 and 0.45 for AC and VS, respectively, indicating the high reliability of across environment prediction. Genomic prediction appears to be a very reliable tool for AE in hybrid wheat breeding. Moreover, high prediction accuracy in CV0 demonstrates the possibility of implementing genomic selection across breeding cycles in related germplasm, aiding the rapid breeding cycle

    Case study of microgrid for electrification and its benefits in rural Nepal

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    Click on the DOI link to access the article (may not be free).This paper describes a microgrid for electrification of an isolated rural village in Nepal. Photovoltaic and various storage systems were modeled to find the optimal design. The economic and environmental impacts are also studied

    Population and conservation threats to the vulnerable Sarus crane Grus antigone in Nepal

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    Abstract Globally, biodiversity is declining due to habitat loss and degradation, over‐exploitation, climate change, invasive species, pollution, and infrastructure development. These threats affect the populations of large waterbird species, such as Sarus crane (Grus antigone), which inhabits agricultural–wetland ecosystems. Despite the burgeoning built‐up areas and diminishing agricultural and wetland spaces, scant research investigates the impact of these changing land uses on the globally vulnerable Sarus crane in Nepal. During the pre‐breeding season from April to June 2023, our comprehensive study meticulously scrutinized Sarus crane population status and factors associated with the occurrences and conservation challenges across 10 specific districts of Nepal. Our study documented a total of 690 individuals of Sarus cranes in five districts. The Lumbini Province has 685 individuals, occupying 11 roosting sites. Conversely, the remaining five districts have no Sarus cranes presence during this period. Wetland, farmland and built‐up areas exhibited a significantly positive influence on Sarus crane occurrences in the Lumbini Province. Additionally, we recorded 47 fatalities of Sarus cranes over the past 13 years in the Lumbini Province due to electrocution and collisions. Our study provides a baseline dataset crucial for developing conservation policies, particularly during the dry season when Sarus crane populations tend to congregate in larger flocks. The adaptation of the Sarus crane to urbanized landscapes exposes them to several anthropogenic threats in the coming days. Therefore, protecting wetlands and farmland areas and adopting transboundary conservation approaches are imperative for the long‐term conservation of the Sarus crane and its habitat
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