GENETIC-EFFECTS OF YIELD AND ITS COMPONENTS IN INTERSPECIFIC CROSSES OF COTTON

Seven varieties of cotton, three of which belong to Gossypium hirsutum L. and four to G. barbndense L. were crossed to obtain a set of diall el excluding reciprocals. Analysis of variation among crosses shows a preponderance of general combining ability (GCA) effects over specific combining ability (SCA) effects for all traits studied. SCA variance through consistently smaller than GCA variances were, however, signifi cant for lint per cent and boil size. The results thus indicate that a lthough most of the differences noted among crosses for yield and its components were due to genes with primarily additive effects, the rela tively small contributions of non-additive effects cannot be overlooke d. The implications on breeding procedures in cotton of these findings are discussed.