Investigating the Role of Allelic and Inter-Locus Interactions That Drive Heterosis for Grain Quantity and Quality of Sorghum bicolor

Heterosis is described as the superiority in size, vigor, fertility or overall productivity of a hybrid over its parents, and it is an important genetic component in improvement of major grain and vegetable crops. Recent advances in genotyping technologies (i.e., genotype by sequencing; GBS) create new opportunities in dissecting this phenomenon using multi-parent populations. We have recently developed the heterotic trait loci (HTL) mapping for genetic dissection of heterosis in a diallel [1]. Heterosis measured in two field trials, and analyses of consecutive F2 populations, shed light on the role of intra- and inter-locus interactions in mediating heterosis. Although significant heterotic trait loci (HTL), which represent significant association of specific local heterozygosity with heterosis, were initially identified, further fine mapping unravel dominant complementations within these overdominant loci. In addition, expanding the study of morphological traits and including quality traits (nitrogen content) show similar complementation between non-linked dominant loci. Nevertheless, combining this approach with path analysis of yield components allowed to identify several significant loci that regulates grain yield and nitrogen content, including some candidate genes which is the focus for molecular and biochemical interrogation. We also combine advanced allele mining approaches using next generation sequencing (ComSeq[2]) to complement our genotype-to-phenotype studies with isogenic mutants for the candidate genes. These results highlight the major role dominance complementation plays in shaping heterosis and the power of implementing ultra-high genetic resolution for molecular study of mechanisms underlying agricultural yield in hybrids.

Title: Investigating the Role of Allelic and Inter-locus Interactions that Drive Heterosis for Grain Quantity and Quality of Sorghum bicolor

 

Submitter's E-mail Address:eyal.fridman@mail.huji.ac.il

Session Selection:Sorghum/Millet

Imri Ben-Israel

Dr. Eyal Fridman

The Hebrew University
Email: eyal.fridman@mail.huji.ac.il