Genetic analysis in sorghum for yield and shoot fly resistance attributes

Abstract

An experiment was conducted at the Centre for Millets Research, Sardarkrushinagar Dantiwada Agricultural University, Deesa during kharif,2022 to estimate general and specific combining ability effects and components of genetic variance for yield and shoot fly resistance attributing traits in sorghum. The mean sum of squares due to general and specific combining ability was found highly significant for all the studied characters. The estimates of σ2gca/σ2sca revealed preponderance of non-additive type of gene action in the expression of yield and shoot fly resistance associated characters. Considering gca effect the parents SWARNA, GJ 43 and GNJ 1 revealed significantly superior gca value and were identified as a good general combiner for yield contributing characters. The parents IS 18551 and IS 2205 were good general combiners for shoot fly resistance attributes. The crosses IS 18551 × SWARNA, GJ 43 × GNJ 1 and IS 2205 × SWARNA for grain yield per plant recorded the highest sca effects which involved poor × good; good × good and poor × good combination, respectively. The cross, IS 18551 × IS 2205 showed significant desirable sca effects for almost all the characters related to shoot fly resistance, viz., seedling vigour, seedling glossiness and shoot fly dead heart at 14th, 21st and 28th days after emergence (DAE).The regression of Wr on Vr was desirable and near unity for seedling vigour, seedling glossiness, days to flowering, total plant height, shoot fly dead heart at 14 DAE, shoot fly dead heart at 21 and 28 DAE, hydrocyanic acid content, grain yield per plant, protein content and total phenol content. The regression line intercepted Wr axis below the origin indicating over dominance for total plant height, shoot fly dead heart at 14 DAE, hydrocyanic acid content and total phenol content. The component D was significant for all the traits suggesting predominance of additive gene effects. The estimates H1 and H2 were significant for all the traits except days to flowering. The magnitude of non-additive (H1) component was higher than additive (D) component for all the traits except seedling vigour which showed more important role of over dominance. In Wr-Vr graph scattering of parental array point along the regression line for the traits hydrocyanic acid content, crude protein content and total phenol content revealed significant genetic diversity among the parents for the above traits.

Keywords

• sorghum
• shoot fly
• gca
• sca