Yield Stability in Relation to Maturity in Grain Sorghum1
- Mohammad Saeed and
- C. A. Francis2
Yield stability in 54 grain sorghum [Sorghum bicolor (L.) Moench] genotypes in relation to maturity was studied in Nebraska and Kansas across 48 environments. The genotypes were categorized into early, medium, and late maturity groups based on the mean number of days from planting to physiological maturity. A stability analysis was done for each maturity group and for all genotypes ignoring groups. Simple correlation coefficients between stability parameters for yield and stability parameters for yield components were determined. Significant genotype ✕ environment and genotype ✕ environment (linear) interactions were detected for yield and seeds/m2. More than half of the variation in the linear responses of genotypes to environments was attributable to wide differences in maturity among genotypes. Stability analysis of all genotypes ignoring maturity groups showed a significant linear and quadratic relationship between days to flowering and stability parameters, regression coefficient and deviations from regression, respectively, and suggested that differences in yield stability among genotypes were largely a function of relative maturity. Separate stability analysis of genotypes in a maturity group revealed no such relationship in the early and the medium groups. Yield stable genotypes were identified in each group but proportionately fewer in the late group. A combined analysis of genotypes without grouping failed to detect this stability of individual genotypes. When genotypes under test have a wide range of maturity, we suggest a better evaluation for yield stability in groups of genotypes with minimal maturity differences. Early and medium maturing genotypes appeared to be more stable than late maturing genotypes. Stability for yield components such as seed number and seed weight should be considered when breeding for yield stability in grain sorghum.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .