Genetic studies on silica and sugar contents in rabi sorghum (Sorghum bicolor L. Moench) as shoot fly resistant traits

Genetics of traits associated with shootfly resistance in rabi sorghum (Sorghum bicolor L. Moench) were studied to understand the nature and magnitude of gene action involved with respect tosilica and sugar contenst. The experiment consisted of nine generations (P₁, P₂, F₁, F₂, B₁, B₂, F₃, B₁F₂ and B₂F₂) of four crosses viz., SPV1587 x RSV458, SPV1587 x RSE3, SPV 1546 x RSV458 and SPV1546 x RSE3. Significance of dominant gene action and its magnitude indicated inheritance of silica content. Magnitude of additive x additive type of non-allelic interaction was found to be more pronounced, indicated additivity for this trait. Gene effects for deposition of silica content were found to be more consistent among all the crosses. The parent RSV458 was found to be promising on the basis of high silica content, individually as well as in cross (SPV1546 x RSV458). Dominance gene action was more pronounced along with predominance of dominance x dominance interaction for inheritance of sugar content in all the four crosses. Parents RSV458 and RSE-3 were found to be most promising for evolving shootfly tolerant genotype.