Development of a screening method for drought tolerance in cotton seedlings
The key to an efficient screening method is the ability to screen large amounts of
plant material in the shortest time possible. Unfortunately, due to the complexity of
drought tolerance, a quick and effective screen for this trait has yet to be established.
The research reported herein was designed to evaluate a screening method for drought
tolerance in cotton (Gossypium hirsutum L.) seedlings. Twenty-one converted race
stocks (CRS) and two cultivars were evaluated for seedling drought tolerance on an
individual plant basis. CRS are day-sensitive primitive lines derived from various wild
race stocks that were converted to day neutrality for use in temperate region plant
improvement programs (McCarty et al., 1993). Genotypes were evaluated October -
November 2004 and February - March 2005 under greenhouse conditions at the Norman
E. Borlaug Center for Southern Crop Improvement, College Station, TX. Seedlings
were subjected to three sequential cycles of drought at 15 days after planting (DAP).
Drought cycles consisted of withholding water until the moisture content of "indicator"
cone-tainers, containing Deltapine 491 (DP 491), had an average volumetric water
content of 0.07. Plants were then watered to field capacity and percent survival was
recorded after 48 hours. Genotypes differed in their percent survival following three consecutive drought cycles. Drought cycles 2 and 3 did not contribute to the separation
of genotypes. DP 491 was the most tolerant genotype evaluated. None of the CRS were
more or less tolerant than Acala 1517-99. CRS M-9044-0165 was the most stable
genotype across the two experiments.
Advisor:Smith, C. Wayne; Thaxton, Peggy; Binzel, Marla; McMichael, Bobbie
School:Texas A&M University
School Location:USA - Texas
Source Type:Master's Thesis
Keywords:cotton drought screen
Date of Publication:12/01/2005