Genetic fingerprinting of diploid and tetraploid cotton cultivars by retrotransposon-based markers

Abstract

Cotton (Gossypium spp.) is the most important natural fiber and oil source worldwide. The genus Gossypium has 45 diploid and 5 allotetraploid species. Currently cotton has only 4 cultivated species, two tetraploid species [G. hirsutum L. and G. barbadense L., (2n = 4x = 52)] and two diploid species [G. arboreum L. and G. herbaceum L., (2n = 2x = 26]. Continuous artificial selection and cultivation of available cotton cultivars has led to genetic erosion and loss of useful genetic loci from the available cotton germplasm. Different molecular markers used in genetic fingerprinting of cottons, revealed narrow genetic variability. In order to provide data on genetic diversity present in our cotton germplasm collection, we carried out genetic fingerprinting study of 17 diploid and tetraploid cotton accessions by inter retrotransposon amplified polymorphism markers. The results showed low-moderate genetic variability (0.0–18%) among the studied cultivars. However, we obtained high genetic variability within each species (45–80%). Moreover, some specific bands (alleles) were identified in these species. Such moderate to high genetic variability in cotton germplasm is of high importance for choosing parental plants for hybridization. Inter retrotransposon amplified polymorphism markers could efficiently differentiate the cultivars and the studied diploid species from tetraploids. Therefore, these are suitable molecular markers for fast screening and genetic fingerprinting of large cotton germplasm.