A global barley panel revealing genomic signatures of breeding in modern Australian cultivars. (9th March 2021)

• Record Type: Journal Article
• Authors: Hill, Camilla Beate; Angessa, Tefera Tolera; Zhang, Xiao‐Qi; Chen, Kefei; Zhou, Gaofeng; Tan, Cong; Wang, Penghao; Westcott, Sharon; Li, Chengdao
• Is Part Of: Plant journal. Volume 106:Number 2(2021)
• Page Start: 419
• Page End: 434
• Publication Date: 2021-03-09
• Subjects: barley -- breeding -- population analysis -- selective sweeps -- genetic diversity -- phenology -- next‐generation sequencing -- GWAS -- gene ontology -- genotyping‐by‐sequencing; Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.15173
• Languages: English
• ISSNs: 0960-7412

Abstract

Significance Statement: Our study demonstrates that despite being more extensively bred, modern Australian barley varieties exhibit higher genetic diversity than historical cultivars, countering the common perception that intensive breeding leads to the genetic erosion of adaptive diversity in modern cultivars. Several loci, particularly those related to phenology, were subject to selection during the introduction of other barley varieties to Australia – these genes might continue to be important targets in breeding efforts in the face of changing climatic conditions. SUMMARY: The future of plant cultivar improvement lies in the evaluation of genetic resources from currently available germplasm. Today's gene pool of crop genetic diversity has been shaped during domestication and more recently by breeding. Recent efforts in plant breeding have been aimed at developing new and improved varieties from poorly adapted crops to suit local environments. However, the impact of these breeding efforts is poorly understood. Here, we assess the contributions of both historical and recent breeding efforts to local adaptation and crop improvement in a global barley panel by analysing the distribution of genetic variants with respect to geographic region or historical breeding category. By tracing the impact that breeding had on the genetic diversity of Hordeum vulgare (barley) released in Australia, where the history of barley production is relatively young, we identify 69 candidate regions within 922 genes that were under selection pressure. We also show that modern Australian barley varieties exhibit 12% higher genetic diversity than historical cultivars. Finally, field‐trialling and phenotyping for agriculturally relevant traits across a diverse range of Australian environments suggests that genomic regions under strong breeding selection and their candidate genes are closely associated with key agronomic traits. In conclusion, our combined data set and germplasm collection provide a rich source of genetic diversity that can be applied to understanding and improving environmental adaptation and enhanced yields.