Abstract:A-genome diploid wheats represent the earliest domesticated and cultivated wheat species in the Fertile Crescent and include the donor of the wheat A sub-genome. The A-genome species encompass the cultivated einkorn (Triticum. monococcum L. subsp. monococcum), wild einkorn (T. monococcum L. subsp. aegilopoides (Link) Thell.), and T. urartu. We evaluated the collection of 930 accessions in the Wheat Genetics Resource Center (WGRC) using genotyping-by-sequencing (GBS) and identified 13,860 curated SNPs. Genomic … Show more
“…The mean θπ of R. agastum was 0.0026 and this taxon had the highest degree of intraspecific individual diversity among the three studied Rhododendron taxa. A greater degree of differentiation between the natural race of einkorn (β) and the hybrid domesticated variety has been observed, with an F ST value between the β race and domesticated einkorn reaching 0.31 [ 28 ].…”
As an important horticultural plant, Rhododendron is often used in urban greening and landscape design. However, factors such as the high rate of genetic recombination, frequent outcrossing in the wild, weak linkage disequilibrium, and the susceptibility of gene expression to environmental factors limit further exploration of functional genes related to important horticultural traits, and making the breeding of new varieties require longer time. Therefore, we choose bark as the target trait which is not easily affected by environmental factors, but also has ornamental properties. Genome-wide association study (GWAS) of Rhododendron delavayi (30 samples), Rhododendron irroratum (30 samples) and their F1 generation Rhododendron agastum (200 samples) was conducted on the roughness of bark phenotypes. Finally, we obtained 2416.31 Gbp of clean data and identified 5,328,800 high-quality SNPs. According to the P-value and the degree of linkage disequilibrium of SNPs, we further identified 4 genes out of 11 candidate genes that affect bark roughness. The results of gene differential expression analysis further indicated that the expression levels of Rhdel02G0243600 and Rhdel08G0220700 in different bark phenotypes were significantly different. Our study identified functional genes that influence important horticultural traits of Rhododendron, and illustrated the powerful utility and great potential of GWAS in understanding and exploiting wild germplasm genetic resources of Rhododendron.
“…The mean θπ of R. agastum was 0.0026 and this taxon had the highest degree of intraspecific individual diversity among the three studied Rhododendron taxa. A greater degree of differentiation between the natural race of einkorn (β) and the hybrid domesticated variety has been observed, with an F ST value between the β race and domesticated einkorn reaching 0.31 [ 28 ].…”
As an important horticultural plant, Rhododendron is often used in urban greening and landscape design. However, factors such as the high rate of genetic recombination, frequent outcrossing in the wild, weak linkage disequilibrium, and the susceptibility of gene expression to environmental factors limit further exploration of functional genes related to important horticultural traits, and making the breeding of new varieties require longer time. Therefore, we choose bark as the target trait which is not easily affected by environmental factors, but also has ornamental properties. Genome-wide association study (GWAS) of Rhododendron delavayi (30 samples), Rhododendron irroratum (30 samples) and their F1 generation Rhododendron agastum (200 samples) was conducted on the roughness of bark phenotypes. Finally, we obtained 2416.31 Gbp of clean data and identified 5,328,800 high-quality SNPs. According to the P-value and the degree of linkage disequilibrium of SNPs, we further identified 4 genes out of 11 candidate genes that affect bark roughness. The results of gene differential expression analysis further indicated that the expression levels of Rhdel02G0243600 and Rhdel08G0220700 in different bark phenotypes were significantly different. Our study identified functional genes that influence important horticultural traits of Rhododendron, and illustrated the powerful utility and great potential of GWAS in understanding and exploiting wild germplasm genetic resources of Rhododendron.
“…The present core set will serve as a rich source of genetic variations to be utilized in the breeding program and should be coupled with careful phenotyping. In recent years, gene bank curation has been done to explore the novel genetic variations in T. monococcum [73] , T. aestivum [74] , [75] , [76] , [77] , Aegilops tauschii [43] , T. turgidum L. [78] , rye [79] , sorghum [80] , melon [81] , pumpkin [82] , capsicum [83] for trait improvement. Fig.…”
“…It circumscribed to cultivate as wild einkorn. With the introduction of large-scale genomics analysis like genotype by sequencing, SNP array revealed that the origin of T. urartu is the closest genome for subgenome A ( Maccaferri et al, 2019 ; Adhikari L. et al, 2022 ). Furthermore, with the commencement of remarkable genetic diversity losses in the pericentromeric and donating B genome by T. speltoides give a new tetraploid T. turgidum .…”
Section: The Wealth Of Indian Wheat Genetic Resources and Its Conserv...mentioning
confidence: 99%
“…Based on the ex situ germplasm collection size conserved in long-term storage, the Indian National Genebank has the second-largest collection in the world (a total of 459,885 accessions conserved in NGB, India, as on 31 March 2022), next only to the USDA Genebank ( Tyagi et al, 2015 ). In the case of wheat, its ex situ collection in the National Genebank (34,000 accessions as on 31 March 2022) is the fifth-largest collection in the world (CIMMYT Genebank ranks first) ( Jacob et al, 2015 ; Adhikari L. et al, 2022 ). These indigenous germplasm accessions are a valuable repository of economically important traits.…”
Wheat is one of the major staple cereal food crops in India. However, most of the wheat-growing areas experience several biotic and abiotic stresses, resulting in poor quality grains and reduced yield. To ensure food security for the growing population in India, there is a compelling need to explore the untapped genetic diversity available in gene banks for the development of stress-resistant/tolerant cultivars. The improvement of any crop lies in exploring and harnessing the genetic diversity available in its genetic resources in the form of cultivated varieties, landraces, wild relatives, and related genera. A huge collection of wheat genetic resources is conserved in various gene banks across the globe. Molecular and phenotypic characterization followed by documentation of conserved genetic resources is a prerequisite for germplasm utilization in crop improvement. The National Genebank of India has an extensive and diverse collection of wheat germplasm, comprising Indian wheat landraces, primitive cultivars, breeding lines, and collection from other countries. The conserved germplasm can contribute immensely to the development of wheat cultivars with high levels of biotic and abiotic stress tolerance. Breeding wheat varieties that can give high yields under different stress environments has not made much headway due to high genotypes and environmental interaction, non-availability of truly resistant/tolerant germplasm, and non-availability of reliable markers linked with the QTL having a significant impact on resistance/tolerance. The development of new breeding technologies like genomic selection (GS), which takes into account the G × E interaction, will facilitate crop improvement through enhanced climate resilience, by combining biotic and abiotic stress resistance/tolerance and maximizing yield potential. In this review article, we have summarized different constraints being faced by Indian wheat-breeding programs, challenges in addressing biotic and abiotic stresses, and improving quality and nutrition. Efforts have been made to highlight the wealth of Indian wheat genetic resources available in our National Genebank and their evaluation for the identification of trait-specific germplasm. Promising genotypes to develop varieties of important targeted traits and the development of different genomics resources have also been highlighted.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
