Allelic relationship between restorer genes for A₁ and A₄ CMS systems in pearl millet

Abstract

Understanding the allelic complementation of restoration among the stable restorer lines will contribute to robust pearl millet restorer breeding program. Thus, present study aimed to test allelic relationship between four diverse restorer lines each for A 1 and A 4 cytoplasmic male sterility (CMS) systems to find linkage between restorer genes carried by different restorers of each CMS systems. Six testcrosses were developed for each CMS system by crossing each of A 1 and A 4 male sterile lines (81A 1 and 81 A 4) with all possible combination of F 1 s among four A 1 restorers and A 4 restorers, respectively. Almost all the plants in these testcrosses showed complete male fertility indicating presence of same fertility restoration gene (allelic) is present in all the four restorer lines of A 1 CMS system. Similar results were found for A 4 CMS system. This single gene system within A1 and A4 provides the opportunity to breeders to incorporate this allelic restorer gene into any of the advanced lines for its rapid conversion into new restorer lines besides to search for new restorer gene for future diversification.

Inheritance of fertility restoration of A4 cytoplasm in pearl millet [Pennisetum glaucum (L.) R. Br.]

“…Gupta et al 2018 studied inheritance of fertility restoration for A 5 cytoplasm and reported trigenic inheritance of male fertility restoration, where dominant alleles at any two of the three duplicate complimentary loci will lead to fertility restoration. Govindaraj et al, 2018 reported allelic relationship between fertility restorer genes responsible for fertility restoration in A 1 and A 4 cytoplasm. Singhal et.…”