Study of Gene Effects for Stalk Sugar Yield and Its Component Traits in Sweet Sorghum [Sorghum bicolor (L.) Moench] Using Generation Mean Analysis

Generation mean analysis was carried out to estimate the nature and magnitude of gene effects for sugar yield and its component traits in sweet sorghum [Sorghum bicolor (L.) Moench. Six basic generations, namely P1, P2, F1, F2, BC1P1, BC1P2 of four crosses involving seven diverse parents were evaluated in rainy 2009. The mean performance of the F1 in all the crosses indicated dominant gene effect for all the characters. Simple additive-dominance model indicated presence of epistatic interaction. High positive additive × additive interaction effects were found in all the crosses. Higher magnitude of dominance and dominance × dominance gene interactions which were found minimizes the expression of heterosis leading to non-exploitation of crosses with duplicate epistasis. Reciprocal recurrent selection and/or biparental mating in early segregating generations has been suggested for development of high sugar yielding genotypes in view of the genotypes studied.