Title: Molecular markers linked to fertility restorer gene in A<sub>2</sub> cytoplasm male sterility of pigeon pea [<i>Cajanus cajan</i>]
Abstract: In pigeonpea the cytoplasmic-genetic male sterility (CMS) system is considered to be a feasible approach for the development of hybrids. Identification of CMS lines and their putative restorers using molecular markers in the early stage of growth is an important and economical in long duration pigeonpea. Based on phenotyping, the 120 plants of F 2 designated as fertile and sterile. Both visual and pollen staining phenotyping unequivocally exhibited 85 fertile: 35 sterile plants in F 2 population. The segregation of F 2 for fertility restoration of A 2 cytoplasm indicated 3F:1S segregation indicating dominant monogenic control of fertility restoration. Bulk segregant analysis revealed that 10 of the 139 polymorphic decamer RAPD markers produced precisely distinct bands subjective to fertility restorer DNA bulk while, none of the SSR was found polymorphic between bulks. Two of them viz ; OPC 7 617 (GTC CCG ACG A) and OPK 3 860 (CCA GCT TAG G) evinced clear and unambiguous bands for fertility restorations in F 2 population at 0.5 and 1.0 cM, respectively. They could be exploited as a precise selection tool for seminal but stubborn character like restoration of fertility in male sterile lines that has germane significance in otherwise immensely important heterosis breeding in pigeonpea. Key Words C. cajan, C. scarabaeoides, CGMS system, RAPD, SSR