HETEROSIS AND INBREEDING DEPRESSION IN INDIAN MUSTARD

Abstract

Thirty three mustard (Drassica juncea) hybrids derived from crosses of eleven lines and three testers along with their FI, F1 and parents were evaluated to estimate heterosis, inbreeding depression and combining ability. Manifestation of heterosis was maximum for secondary branches per plant and minimum for primary branches per plant. In general, high heterosis for a trait was accompanied by significant inbreeding depression. The estimates of sca were greater than the gca for yield and its components. The use of at least one, preferably both, good general combiners in a particular cross for the trait under consideration was advocated. Based on these results it is suggested that heterotic response, level of inbreeding depression and gca effects of the parents, if considered together, can be helpful in identification of crosses which are likely to yield better performing pure lines by applying suitable breeding procedures.