Title: Meta QTL Analysis Using Three Connected Mapping Populations in Sorghum bicolor for Drought Tolerance Related Traits

Biography:

Techale is serving as an Assistant Professor in the Department of Horticulture and Plant Science at Jimma University, Jimma, Ethiopia. He did his B.Sc. in Horticulture at Jimma University and MSc in plant breeding at Haramaya University in Ethiopia. He is attending his PhD in Plant Molecular Breeding at the University of Georgia in USA and Jimma University in Ethiopia. 

Abstract

The genetic architecture of drought tolerance is expected to involve multiple loci that are unlikely to all segregate for alternative alleles in a single bi-parental population. Therefore, the identification of quantitative trait loci (QTL) that are expressed in diverse genetic backgrounds of multiple bi-parental populations provides evidence about both background-specific and common genetic variants. The purpose of this study was to map QTL related to drought tolerance using three connected mapping populations of different genetic backgrounds, to gain insight into the genomic landscape of this important trait in elite Ethiopian germplasm. The three bi-parental populations, each with 207 F_2:3 lines were evaluated using an alpha lattice design with two replications under two moisture stress environments. Drought tolerance related traits were analyzed separately for each population using composite interval mapping, finding a total of 105 QTLs. All the QTLs identified from individual populations were projected on a combined consensus map, comprising a total of 25 meta QTLs for seven traits. The consensus map allowed us to deduce locations of a larger number of markers than possible in any individual map, providing a reference for genetic studies in different genetic backgrounds. The mQTL identified in this study could be used for marker- assisted breeding programs in sorghum after validation. Only one trait, reduced leaf senescence, showed a striking bias of allele distribution, indicating substantial standing variation among present varieties that might employed in improving drought tolerance of Ethiopian and other sorghums.