Integration of biotechnology and conventional breeding to develop citrus seedless cultivars in Vietnam

Citrus is a major fruit product in Vietnam. However, most of citrus cultivars are high number of seeds that curb in developing citrus production and fruit quality. Seedless is an important trait in Citrus. Hence, the objective of current study was to integrate the conventional breeding and biotechnological approaches for developing Citrus seedless cultivars in the country. By integration between conventional and biotechnological breeding approaches, 5 new seedless cultivars have been released and approved. The method of tetraloid induction by colchicine in vivo treatment on mature buds and following interploid hybridization have showed highly effective for pummelos triploid breeding. Numerous triploids have been obtained in Citrus nobilis Cam Sanh by embryo rescue in vitro of aborted and small seeds and also developed by interploid crosses. The method of tetraploid induction on buds of mature diploid plants and grafting of young triploid buds on mature trees is two effective ways for shortening breeding circle in Citrus. The intensive field test is urgently needed for next 5 years to select and release the best triploids for production in the country.