CIMMYT annually distributes improved germplasm developed by its researchers and partners in international nurseries trials and experiments. The High Rainfall Wheat Screening Nursery (HRWSN) contains spring bread wheat (Triticum aestivum) germplasm adapted to high rainfall areas (Mega-environment 2).
International Durum Yield Nurseries (IDYN) are replicated yield trials designed to measure the yield potential and adaptation of superior CIMMYT-bred spring durum wheat germplasm that have been developed from tests conducted under irrigation and induced stressed cropping conditions in northwest Mexico. These materials have been subjected to numerous diseases (leaf, stem and yellow rust; Septoria tritici blotch) and varied growing environments. It is distributed to 70 locations, and contains 50 entries.
International Durum Screening Nursery (IDSN) distributes diverse CIMMYT-bred spring durum wheat germplasm adapted to irrigated and variable moisture stressed environments. Disease resistance and high industrial pasta quality are essential traits possessed in this germplasm. It is distributed to 100 locations, and contains 150 entries.
The Harvest Plus Advanced Nursery (HPAN) contains spring bread wheat (Triticum aestivum) germplasm adapted to ME1 (Optimally Irrigated, low rainfall environment) and ME5 (Warmer area environment) environments. It has 100-200 entries with a single replication, white grain color and distributed to more than 35 locations.
This dataset include data from a national wheat survey in Ehiopia in 2016 during the main season for a DNA fingerprinting study. The data contain wheat varieties genotyped using DNA fingerprinting (DNA FP), farmers recall survey and matching of DNA FP with farmers recall.
The objective of the Landscape Diagnostic Survey (LDS) for wheat is to bridge the existing data-gap around current production practices of wheat, and also to help in evidence-based planning. The LDS is designed in a way that data is collected from randomly selected farmers spread uniformly within a KVK (government extension system) domain/district. Data has been collected from farmers largest wheat plot for winter season of 2018. Survey questionnaire captures all production practices applied by farmers from land preparation to harvesting, including detailed sections on fertilizer use, weed control and irrigation application. Data is captured through electronically enabled Open Data Kit (ODK) tool on mobile phone or tablet.
Genetic architecture of grain yield (GY) has been extensively investigated in wheat using genome wide association study (GWAS) approach. However, most studies have used small panel sizes in combination with large genotypic data, typical examples of the so-called ‘large p small n’ or ‘short-fat data’ problem. Further, use of bi-allelic SNPs accentuated ‘missing heritability’ issues and therefore reported markers had limited impact in wheat breeding. We performed haplotype-based GWAS using 519 haplotype blocks on seven large cohorts of advanced CIMMYT spring bread wheat lines comprising overall 6,333 genotypes. In addition, epistatic interactions among the genome-wide haplotypes were investigated, an important aspect which has not yet been fully explored in wheat GWAS in order to address the missing heritability. Our results unveiled the intricate genetic architecture of GY controlled by both main and epistatic effects. The importance of these results from practical applications in the CIMMYT breeding program is discussed.
Conducted genome-wide association scan (GWAS) and explored the possibility of applying genomic prediction (GP) for Anther Extrusion (AE) in the CIMMYT hybrid wheat breeding program
The Stem Rust Resistance Screening Nursery (STEMRRSN) is a single replicate nursery that contains diverse spring bread wheat (Triticum aestivum) germplasm adapted to all mega-environments with total 50-100 entries and white/red grain color.