DNA Fingerprint ing of Upland Cot ton (Gossypium hirsutum) Hybrids and their Parents Using RAPD and SSR Markers

Abstract

Cotton, the white gold is also known as the king of fiber crops and is the main raw material for textile industry. Use of morphological differences, between true hybrids and off types in grow out test (GOT) for genetic purity analysis, are not always apparent and cannot be recognized easily. Further, morphological traits are costly, tedious to score and environment sensitive. Alternatively, it is suggested that recent breakthrough in molecular markers can be employed in genetic purity analysis. Molecular markers such as RAPD and SSR markers were used for the parental identification of different hybrids. The experiment was carried out at the Biotechnology Laboratory, Main Cotton Research Station, Surat, Gujarat during 2013-14. In present study, seven RAPD markers (RP10, RP20, RP21, RP22, RP25, SRT-6 and SRT-13) and six SSR markers (MGHES-62, TMB-1181, TMB-0409, TMB-1791, JESPR-153 and CM-45) were identified to be polymorphic between parents of the hybrids studied. Among these primers JESPR-153 is able to identify the true hybrid (Heteroallelic). These reported markers showed specific size of amplicons which helped in parental confirmation. Results indicated that, these two markers-RAPD and microsatellites individually or in combination are more reliable for identification and testing of genetic purity of cotton hybrids. These highly informative markers not only differentiated the parent genotypes but also confirmed the parentage of their true F₁ hybrids. Our findings revealed that RAPD and SSR procedures were excellent genomic tools for parentage confirmation and hybridity determination, and would also enhance efficiency of our breeding programmes through marker assisted selection.