Pointed Gourd (Trichosanthes dioica): A Promising Dioecious Cucurbit

Pointed Gourd (Trichosanthes dioica Roxb.) is one of the most important cucurbit vegetables in tropical and sub-tropical regions but successfully grow in Japan because of its wide range of variabilities. Silver nitrate at 50ppm found as effective to induce hermaphrodite flower with viable pollen and crossbreeding among female genotypes produced almost same size of fruits of normal female and male crossing. Green fruit is the main edible part but presence of a large number of seeds are prompting to produce parthenocarpic seedless or less-seeded fruits. Plant growth regulators induced parthenocarpy is possible through the application of GA3 at 200ppm, CPPU and TIBA at 100ppm at anthesis. However, triploid breeding technique could be useful in developing genetically stable parthenocarpic line and tetraploid induction is possible with 0.5% colchicine for 72 h soaking of mature seeds. Sex expression and fruit setting is found as sensitive to the growing season temperature where low temperature increases the number of female flowers and high temperature promotes the production of male flower.