Identification of intergeneric f₁ hybrids of pitayas through molecular approach

Intergeneric cross between diploid Hylocereus polyrhizus, as the female parent, and the tetraploid Selenicereus megalanthus, as the male parent, was previously conducted by the Department of Plant Science, UNIMAS, with a quest to produce F1 hybrid. Conventional identification of the hybrids is laborious and time-consuming. Thus, this project was conducted in order to provide an alternative for identification of hybrids via advancement in molecular marker, inter simple sequence repeat (ISSR). Genomic DNA of both parental and 10 hybrids of root samples were successfully isolated using modified CTAB method. Following PCR amplification using two selected ISSR primers (ISSR 811 and 817), parental sample and only a total of five hybrids were successfully amplified. A dendrogram was constructed based on UPGMA clustering analysis using NTSYS-pc software. Analysis on the polymorphic banding patterns and dendrogram showed that a majority of F 1 hybrids exhibit genetic similarity with female parents. For ISSR 811, two hybrids showed additional bands distinct from parental species. Mutation polymorphism may occur which lead to genetic changes in hybrids