Morphological studies on interspecific F₁ hybrids in genus Citrullus

Interspecific crosses in genus Citrullus involving two accessions of C. colocynthis i.e. cv. GP 3 and cv. GP 177 (diploid, 2n = 22), wild perennial and a cultivar of C. vulgaris var watermelon cv. RW 177-3 (diploid, 2n = 22), a cultivated annual yielded 8 hybrid fruits. Interspecific hybrids showed intermediary values between the parents for most of the attributes studied, though reciprocal differences were there. Hybrid plants were earlier in opening of female flower than respective female parent. F₁ hybrids of the crosses involving C. colocynthis as female parent showed flower shedding and delayed maturity of fruits, consequently, resulting in high rate of seed abortion. Pulp colour, pulp taste and seed coat colour were intermediate in crosses involving C. vulgaris var. watermelon as seed parent. The character expression of F₁s surpassing with the parent either in positive or negative direction was comparable to transgression effect. Resemblance to either of the parent and intermediate character expression were attributed to dominance and additive gene action, respectively.