Full Text
(189 K)

Laboratory Tests Used to Screen for Chilling Tolerance in Cotton Genotypes

D.H. Schulze, N.W. Hopper, J.R. Gannaway, G.M. Jividen


Cotton production (quantity and quality) on the Texas High Plains is limited by the number of heat units available during the growing season. Producers, therefore, face a dilemma in their planting schedule. Early plantings to obtain good yield and fiber quality by having the crop mature early in the fall when temperatures are warm, risk poor stand establishment from cool spring soils. Later plantings, to ensure good stand establishment in warmer soils, risk poor yield and fiber quality from crop maturation in the cooler late fall conditions. Cold tolerant cotton genotypes would allow earlier planting; thus, allowing for more profit from reductions in seeding rates and obtaining greater yields of high quality fiber. This study was initiated to screen a number of commercial and experimental cotton genotypes for both early and late season cold tolerance and to identify or develop laboratory test(s) to identify this trait. The test will then be available to breeders to initially screen large numbers of breeding lines for this trait prior to field testing those lines that have been identified as cold tolerant. Thirty two genotypes were planted on April 12 and June 9 to identify early and late season cold tolerance, respectively, in field situations. Field parameters were then correlated with lab tests conducted on seed and seedlings. The EC 40 F and Pouch Germination tests correlated with several field parameters at the 5% significance level, but r2 values were low. We believe that variables other than temperature masked results in the field and are responsible for the low r2 values. Therefore, a cold temperature room has recently been obtained for future testing that allows for control of all variables as temperature is changed to better identify a suitable screening test.

Reprinted from Proceedings of the 1996 Beltwide Cotton Conferences pp. 1240 - 1243
©National Cotton Council, Memphis TN

[Main TOC] | [TOC] | [TOC by Section] | [Search] | [Help]
Previous Page [Previous] [Next] Next Page
Document last modified Sunday, Dec 6 1998