Salvaging of abortive embryos from mature tetraploid x diploid watermelon fruits through in vitro culturing and realization of a triploid seedless watermelon

摘要

Fruits derived from a cross between the autotetraploid and diploid parental lines of watermelon (Citrullus lanatus Thunb. [Matsum. & Nakai]) cv. Arka Manik bore three types of seeds which included normal black ones with hard testa, white seeds with soft testa, and abortive ones with papery testa. A small proportion of the latter two types (about 2-4%) which normally fail to germinate and express in the natural course of seed perpetuation could be revived under in vitro conditions, revealing the presence of underdeveloped embryo in them. One such line that emanated from an abortive papery seed having a chromosome constitution of 2n = 3x = 33 was further micropropagated, yielding seedless fruits in the field. This approach holds promise for salvaging undeveloped embryos from mature multi-seeded fruits.