Genetic basis of variation for seedling traits in Gossypium hirsutum L.
A 6 × 6 complete diallel analysis was performed to study the inheritance of seedling traits in cotton. Significant differences among genotypes showed the genetic variation and formal analysis predicted the presence of both additive and non-additive genetic variation for inheritance of seedling traits. Further, the estimates of genetic components D, H1 and H2 confirmed the presence of both additive and non-additive genetic effects for all the characteristics. Dominant genes were responsible for the
increase of seedling shoot length, root length, shoot weight and root weight. However, recessive genes were accountable for the increase of shoot root ratio by length and by weight. Seedling shoot length, root length and root weight can be improved through heterosis breeding. The magnitude of broad sense heritability was greater than narrow sense for all the six traits under study hence diminished the scope of selection in the early segregating generation therefore pedigree breeding method is suggested for the improvement of these traits.
Key words: Additive dominance model, gene action, Gossypium hirsutum L, heritability, seedling traits.