Interspecific Hybridization between Gossypium hirsutum and G. armourianum: Morphological and Molecular Characterization of Hybrids

Abstract

The interspecific hybrids G. hirsutum cv. LRA 5166 X G. armourianum (Hybrid 1) and G. hirsutum cv. Sumangala X G. armourianum (Hybrid 2) were genotyped using Random Amplified Polymorphic DNA (RAPD) markers to confirm hybridity. For hybrid 1, 11 of 30 random primers were informative and 15 of 34 primers were informative for hybrid 2. Based on the presence or absence of DNA bands in the female parent, triploid hybrid and male parent, the molecular markers could be classified into seven Types (I- VII). Results indicated that 48.2 % and 55.5 % of the RAPD markers had additivity among parents and off-spring in hybrid 1 and hybrid 2, respectively. However 41.1% and 33.6% of parental markers (Type III, V and VII) were absent in hybrid 1 and hybrid 2, respectively. For both hybrids 11% of the markers were unique (Type VI). The hybrids having Type IV markers (male specific) clearly showed that DNA based technology such as RAPD can be used to distinguish between true inter-specific hybrids of Gossypium and parental selfs. The morphological and cytological characters augmented with RAPD analysis indicated clear distinction between the parents and the resultant hybrids.