The Molecular Marker Study On Sex Differentiation Of Momordica Charantia. L

Bitter melon (Momordica charantia L.) is a member of Cucurbiteae and an herbaceous trailing annual capable of spreading in all directions. It is a monoecious plant that is cultivated around the country and East Asia for its immature fruits with highly medicinal value.Molecular markers have been widely used in genetic relationship, genetic polymorphism , construction of genetic map , gene location, molecular markers assisted selection , and varieties identification in the vegetable researches and production, but there has been little research about bitter melon. This paper studied the molecular markers related to the sex differentiation of bitter melon with RAPD (Random Amplified Polymorphism DNA) and ISSR (inter-simple sequence repeat).The main results were as following:1. The genomic DNA of bitter melon with high concentration and purity could be obtained with the improved method of CTAB, which was good enough for RAPD and ISSR amplification. And the genomic DNA can be completely digested.2.RAPD markers linked to sex were selected by screening 200 primers. The marker amplified by S30 and S66 were present in all female individuals while absent from all male individuals. It showed that it was a marker closely linked to sex. This work will do great help on cloning sex-linked gene.3. Based on the S30₅₅₀ sequence, a pair of primer P1 and P2 was designed, the marker of RAPD-S30₅₅₀ was successfully converted into SCAR marker SR₅₅₀. The result showed that S30₅₅₀ was a female marker linked to sex.4. Study molecular markers linked to sex differentiation in bitter melon, we set up the system of ISSR-PCR.5. ISSR markers linked to sex were selected by screening 100 primers. The marker amplified by 807-400bp, 809-900bp and 810-1400bp were present in all female individuals while absent from all male individuals. It showed that there were three female markers closely linked to sex. This work will do great help on cloning sex-linked gene.