RAPD Testing of an Interspecific Hybrid Between Gossypium hirsutum and Gossypium sturtianum

摘要

Cotton (Gossypium sp.) is the most important textile fibre crop and is also an important oil seed crop in the world. The genus consists of several tetraploid and diploid species. The wild species are a rich source of useful genes for insect and disease resistance and transfer of these genes into cultivated Gossypium species will have important commercial implications. In the present study, Random Amplified Polymorphic DNA (RAPD) was used to characterize the interspecific hybrid of Gossypium. The interspecific hybrid of G. hirsutum 76IH x G. sturtianum was screened using RAPD markers to test the hybrid nature of the offspring. Out of 55 random primers screened, 28 were selected which revealed 229 RAPD markers. Based on the presence or absence of DNAbands in the female parent, offspring and male parent the molecular markers could be classified into seven types. Type I markers shared bands in both parents and offspring, type II markers shared bands in female and offspring, type III markers shared bands in both parents, type IV markers shared bands in male parent and offspring, type V markers were present only in female parent, type VI were present in offspring only and type VII markers were present only in male parent. Of these, only type IV markersare suitable for identifying true male-specific bands. In this study, 53.7% of the RAPD markers revealed additivity among parents and offspring in the hybrid combination G, hirsutum 76IH x G. sturtianum. However 36.7% of parental markers (types III, V and VII) were absent in the offspring while 9.6% unique markers (type VI) were present in the offspring. The hybrid in the present study showed type IV markers common with male parent, which clearly show that DNA-based technology such as RAPD could be used with greater speed to detect true interspecific hybrids of Gossypium.