Vol. 11, Issue 3 (2022)

Author(s):
DB Lad, AA Bhagat and SP Karande

Abstract:
The present investigation was conducted with generation mean analysis involving six generations (P₁, P₂, F₁, F₂, B₁ and B₂) of four crosses associated with shootfly tolerance in post rainy season sorghum. The joint scaling test for almost all the characters was found highly significant in all the crosses indicating inadequacy of additive-dominance model and presence of higher order interactions. Additive, dominance and epistasis interactions were found operating in control of almost all the Morphophysiological traits associated with shootfly tolerance. Genetic analysis indicated that the additive gene effects with additive x additive (i) and dominance x dominance (l) were predominant for the inheritance of days to 50 per cent flowering, while dominance gene effects with dominance x dominance (l) were found important for trichome density and seedling vigor. However, both additive and dominance gene effects with additive x additive (i) were found important for leaf surface wetness. As regards the non-allelic interactions, additive x additive (i) and dominance x dominance (l) was found important for most of the characters. For the traits governed by additive gene action, simple selection would be effective for crop improvement, while for the traits governed by dominance gene action, the better option would be adoption of heterosis breeding. Duplicate type of epitasis observed in almost all the crosses as well as all the traits associated with shootfly resistance. In the presence of both additive and dominance gene effects with equal magnitude, the reciprocal recurrent selection will be useful in the improvement of traits associated with shootfly tolerance.