Diallel analysis of upland cotton cultivars

Crosses involving eight commercial upland cotton cultivars were performed in all possible combinations to generate 28 hybrids. The eight parental genotypes were also evaluated. Afield experiment was conducted using a triple Latice design (6 x 6) in Itumbiara, Brazil, during the 2000101 growing season. Data of the following agronomic and fiber traits were collected: seedcotton yield, lint yield, seed index, picked lint percent, index of production and earliness, micronaire index, fiber strength, fiber length, uniformity index, short-fiber index, fiber elongation, CSP index, reflectance and yellowness and used in the analysis of variance as proposed by Griffing (1956), method 4. Significant differences were detected among treatments and the estimates of combining abilities. Additive gene action prevailed for most traits studied. Both positive and negative heterotic values were detected, demonstrating the potential of hybrid combinations for trait improvement in breeding programs.