Heterosis, Combining Ability and Gene Action for Yield in Bottle Gourd

The experiment was conducted at the experimental\r\nfield of Olericulture Division, Horticulture Research Centre (HRC), Bangladesh\r\nAgricultural Research Institute (BARI), Gazipur, Bangladesh during the winter\r\nseason of 2018-2019 to study the genetic architecture of yield in a seven parent half\r\ndiallel cross of bottle gourd. The values of mean square for GCA (general\r\ncombining ability) and SCA (specific combining ability) were highly significant\r\nwhich suggested the presence of both additive and non-additive genetic variance\r\nin the population. But the higher magnitude of GCA compared to SCA indicated\r\npredominance of additive genetic variance. In most of the cases, the cross\r\nbetween poor and poor parents showed positive SCA effect for fruit yield, which\r\nindicated the higher yield. The estimates of significant positive better parent\r\nheterosis ranged from 6.27 to 49.72 percent. Analysis of genetic components of\r\nvariation suggested that additive components were more important in the\r\ninheritance of fruit yield. This character was observed being controlled by two\r\nto three pairs of genes or groups of genes. Narrow sense heritability was 23\r\npercent indicating probability of selection in generations. The graphical\r\nanalysis also indicated wide genetic diversity among the parents.