Validation of SCAR markers, diversity analysis of male sterile (S-) cytoplasms and isolation of an alloplasmic S-cytoplasm in Capsicum

Abstracts: Cytoplasmic male sterility (CMS) is increasingly being utilized for hybrid seed production of hot pepper (Capsicum annuum). Two CMS specific sequenced characterized amplified regions (SCARs), viz., atp6 607 and coxII 708 developed elsewhere were validated in an array of genotypes possessing male sterile (S-) and normal/male fertile (N-) cytoplasms and their feasible uses in CMS based pepper hybrid breeding have been elaborated. A set of eight maintainer and restorer inbreds were crossed on four CMS lines possessing two independently isolated and commercially utilized S-cytoplasms (Peterson''s and Reddy''s). Based on fertility restoration/maintenance reaction of 32 resulted F1s and on the presence of two SCARs (atp6 607 and coxII 708) in both the S-cytoplasms, it has been concluded that although two S-cytoplasms were isolated and commercially utilized independently, they are genetically same or similar. Through inter-specific hybridization between C. chacoense and C. annuum, a new alloplasmic S-cytoplasm in the genus Capsicum has been isolated and the CMS F1 has been advanced to CMS BC1F1. [Copyright &y& Elsevier]