Project Number: 6435-21000-016-03
Project Type: Trust

Start Date: Jan 01, 2011
End Date: Dec 31, 2011

Objective:
The overall objective is to identify molecular markers associated with quantitative trait loci (QTL) controlling fiber quality traits and yield, and eventually apply the identified markers in breeding. The specific objectives of this agreement are: 1) to identify molecular markers associated with fiber quality traits (length, strength, micronaire, uniformity, elongation) and yield; 2) to determine the effects of random mating on breaking adverse linkage such as between fiber quality and yield.

Approach:
ARS scientists at Mississippi State have developed a unique random mated germplasm population of Upland cotton (Gossypium hirsutum L.) involving six cycles of random mating beginning with an 11 parent half diallel. This germplasm designated RMUP-C5 (Random Mated Upland Population Cycle 5) (Reg. No. GP-893, PI 652942) was released in 2008. The 11 parents used in development represented nonrelated or distantly related cultivars or breeding lines from across the U.S. Cotton Belt. Two hundred thirty three recombinant inbred lines (RILs) from this population are being evaluated for fiber quality traits (strength, length, micronaire, uniformity, etc) and yield. Twenty mapped simple sequence repeat (SSR) markers will be selected from each chromosome based on a high density linkage map. In addition, only markers known to be polymorphic within Upland cotton will be selected. A total of 520 polymorphic SSR markers will be used to scan the genomes of 233 RILs and their 11 parents. Associations between SSR markers and trait of interests will be determined using statistical analysis and other appropriate softwares.