Development Of Cotton New Markers And QTL Mapping Of Upland Cotton

The study has two parts: one part is the screening of microsatellite markers from Cotton ESTs; the other is construction of molecular linkage map and QTL mapping of upland cotton. The major results were presented below: (1) Approximately 94709 EST sequences were searched for identification of SSRs using the Simple Sequences Repeat Identification Tool (SSRIT), 4396 microsatellite sequences were obtained from 94709 EST sequences, about 4.64% of the whole database, a total of 1282(29.2%) dinucleotide repeats and 2411(54.8%) trinucleotide repeats were found in these microsatellite sequences. 25 primer pairs were designed from microsatellite using computer program prime primer (version 5.0). Among the 25 primer pairs, 17 can achieve clear PCR products by electrophoresis. The SSR markers reported in this study were highly polymorphic between Gossypium Hirsutum and Gossypium arboreum but were low polymorphic in Gossypium Hirsutum L. In order to evaluate tranfer-ability of EST-SSRs, we also select six species (Gossypium Hirsutum, Zea mays, Lycopersicum escuentum, Brassica napus, Beta vulgaris, Abutilon theophrasti) to detect the product. Among the primers Cri1, Cri3, Cri4, Cri7, Cri9, Cri14 and Cri15 have products in all of these six species. Cri16, Cri17 have no product in Z. mays, L. escuentum and B. vulgaris. And Cri13 has no product in L. escuentum and B.vulgaris. (2) CCRI36, a short season cotton variety, and TM-1 were used to create 207 F₂ segregating population in Anyang city. The two parents were used to screen 73 polymorphism markers from 518 pair SSR primers, 1200 RAPD primers and 153 of pair SRAP primers. The 207 F₂ populations were tagged and mapped with 73 polymorphism markers, including 25 SSR, 35 RAPD and 13 SRAP markers. 43 of the informative loci were used in linkage map...