Cytoplasmic-nuclear male sterility in pearl millet: comparative RFLP and transcript analyses of isonuclear male-sterile lines

Abstract

The identification of diagnostic cytoplasmic molecular markers is of prime interest to pearl millet breeders wishing to identify sources of cytoplasmicnuclear male sterility (CMS) which can be used as an alternative to the single source currently used in the production of F hybrid seed. Here, we report the classification of five pearl millet CMS sources based on RFLP analysis of isonuclear lines carried out using mitochondrial gene-specific DNA probes in combination with eight restriction endonucleases. On the basis of RFLP data, the five CMS cytoplasms can be distinguished from each other and from the isonuclear fertile cytoplasm. In addition, based on cox1, cox3, atp6 and atp9 polymorphisms, these lines can be classified into two major groups: one corresponds to A , A , A and A cytoplasms, and the other consists of the A cytoplasm. Our results suggest that a rearrangement involving the cox1 gene might be related to CMS in the first group (A , A , A and A ), whereas a rearrangement within the atp6/cox3 cluster region might be related to CMS in the second group (A ).

Effect of cytoplasm and cytoplasm-nuclear interaction on combining ability and heterosis for agronomic traits in pearl millet {Pennisetum glaucum (L) Br. R}

“…Besides, different qualitative and quantitative characters including yield and its components are known to be influenced by cytoplasmic genes. Thus there is a strong argument for cytoplasmic diversification of hybrids for improving yield and resistance to biotic and abiotic stresses (Scheifele et al 1970;Rai et al 1996;Delorme et al 1997;Ekiz et al 1998;Bao and Xia 1999;Stamp et al 2000;Moran and Rooney 2003;Tao et al 2004). Also, the availability of various CMS sources in a crop species provides an array of choices to the plant breeders to diversify both genetic and cytoplasmic bases in hybrid cultivars.…”

Genetic diversity among pearl millet maintainers using microsatellite markers

“…Of the various DNA markers, restriction fragment length polymorphisms (RFLPs) (Liu et al. 1994, Delorme et al. 1997, Bhattacharjee et al.…”

Exploitation of Heterosis in Pearl Millet: A Review

“…These systems can be differentiated by differential expression of male fertility restoration genes or by variations in mitochondrial gene expression. Detailed restriction fragment length polymorphism (RFLP) analysis in pearl millet revealed that there were five CMS cytoplasm that were distinct from one another due to the rearrangement of mitochondrial genes, viz., cox1 and atp6, and cox3 , in cluster regions, in which cox1 gene rearrangement led to the formation of A 5 A egp , A 1 and A 4 and other gene alterations led to the formation of A 4 CMS system [ 112 ]. Based on the phenotype of the restorer, genes for different forms of CMS have been identified on different linkage groups [ 98 , 113 ].…”