ISSR Analysis Of Germplasm Resources Of Momordica

Momordica(Momordica charantia L.)belongs to Cucurbitaceae.It is one of the most well-known special vegetables in south China,mainly distributing in Fujian,Guangdong,Guangxi,Taiwan,Hunan and Sichuan.Momordica has been cultivated in china for hundreds of years.Present studies mainly include cultivation,management,physiologically,medicinal ingredients extraction and so on, seldom from the angle of molecular biology.The research on both genetic diversity investigation and idioplasm evaluation systematically are still absent.In this study,inter-simple sequence repeat(ISSR)method was applied to detect genetic variation of cultivated Momordica from 48 samples.The results could provide scientific basis for making right protection strategy and help to foster new cultivars. The main results were as follow:1.Faced the fact that it is difficulty to extract DNA from momordica which contains phenolic compound and quite a lot of sugar,the researcher used modified CTAB method to extract DNA of momordica,which meets ISSR requirements in high quantity.So far it is quite a proper way to extract DNA from momordica.2.Using the reach results of other cucurbitaceous plants,combined with the orthogonal digram and the singer factor optimization,the technological system of ISSR-PCR reaction of momordica has been built up.In the 20μL reaction system,there is 2.0μL 10×Buffer solution with Mg²⁺,30 ng template DNA,0.5μmol/L of primer,250μmol/L of dNTP,1.25 U of TaqDNA enzyme.According to the system,the experimental steps are as follows.5 min predenaturation at 94℃,30 seconds denaturation at 94℃,60 seconds annealing,90 seconds extension at 72℃.The cycle repeats forty times and ends in 10 min extention at 72℃.3.A total of 14 ISSR primers were employed on 48 individuals of cultivated momordica from 96 primers,and 113 scorable amplified polymorphic were detected,of which 100(60.32%)were polymorphic loci.And this research found that primers containing(GA)n,(AG)n sequence resulted in higher levels of amplified polymorphism of momordica.4.According to the clustering analysis of ISSR results,it proved that the genetic similarity index was 0.685～0.865.From the result,genetic diversity and similarity and genetic relationships were revealed.It provides the theoretical foundation for the breeding research of momordica.