Genetic diversity analysis in male sterile lines of sunflower by SSR markers

Abstract

Sunflower (Helianthus annuus L.) is one of the most important oilseed crops in the world. The sunflower hybrids are superior over open-pollinated varieties in terms of yield, self fertility and resistance to diseases [1]. The development of first cytoplasmic genic male sterile (cms) source Helianthus petiolaris (PET-1) [2] coupled with identification of its fertility restoration genes [3] led to the exploitation of hybrid vigor and commercial use of hybrid sunflower. From 1972 onwards, many hybrids have been developed and released for commercial cultivation, but all of them invariably possessed the PET-1 cytoplasm [4, 5]. Large-scale cultivation of hybrids having single cms source enhances the threat of genetic vulnerability which may be subsided by use of newer sources of cytoplasmic male-sterility and fertility restoration genes. The new cms and fertility restoration lines will also provide cytoplasmic diversity for hybrid sunflower production. In sunflower, there are more than 72 sources of cytoplasmic genic male sterile (cms) sources. However due to the poor availability of the effective restorers, the other cms sources are not widely used. In the present study, genetic diversity of 26 cms lines involving various cytoplasmic sources were studied using 20 SSR markers.