Plant & Animal Genomes XIII Conference Plant & Animal Genomes XIII ConferenceJanuary 15-19, 2005
Town & Country Convention Center
San Diego, CA
Mehboob-ur- Rahman , Muhammad Asif , Ihsan Ullah , Kausar Abdullah Malik , Yusuf Zafar
Cotton genome initiative in Pakistan started at the fall of 1996, deals with the DNA-based analysis for gene tagging, development of linkage maps genome mapping, genetic diversity estimates, cultivar purity testing, and launching of marker-assisted selection (MAS). Significant advancements have been made in cotton genomic studies to combat insect pests and diseases. DNA marker studies were conducted to find DNA markers linked with cotton leaf curl disease (CLCD), and different traits conferring insect pest resistance (red color, hairiness, nectarilessness etc). A total of 450 random 10-mer primers and 45 microsatellite loci (SSRs) were surveyed. A polymorphic DNA fragment OPN121180 and three SSRs (CM-43, CM-66 and CM-162) were linked with the disease resistance trait. We have also surveyed the available 450 10-mer random primers and 60 SSRs using bulked segregant analysis (BSA) to warrant map-based cloning for velvet hairiness and red leaf color traits, and developed two preliminary genetic linkage maps. Genetic similarity among elite cotton cultivars released in pre-CLCD era was in the range of 81.5% to 93.41%, declared alarming. In another study, genetic similarity among the elite 20 cotton cultivars developed using exotic resistant germplasm, released in post-CLCD era, was in the range of 81.58% to 94.90%. Our study reflects the need to breed for high genetic diversity to serve as a potential buffer against any natural disaster in advance. Three genes were identified conferring resistance against the CLCD. We proposed naming of these genes R1CLCuVhir , R2CLCuVhir and SCLCuVhir.