Study On The Genetic Diversity Of Melon Germplasm Resource Using RAPD Molecular-marker

China is one of the important places which melon is originating from and has much abundant germplasm resources of melon,especially the thin and thick cultivars.In the long run,conserving genetic resources of melon is a vital issue for the sustainability of the melon industry both in china and in the world.On the hand,the germplasm conserving and collection both protect the vital representative resources and avoid the resources are reduce and repeat in the genetic biotype.On the other hand,it is able to research and use more available germplasm resources by the analysis and set up the core gene bank.According to an incomplete Statistics,it shows that our country have the all over the world germplasm resources of melon about three thousand five hundred.The center of thin melon conserving place is Turpan Xinjiang grape and melon Institution and the center of thick melon conserving place is the melon's room of Zhengzhou Fruit Institution of the Chinese Academy of Agricultural Sciences.The author selected thirty varieties of representative melon resource and researched their genetic diversity using the random amplified polymorphic DNA(RAPD)marks.The results not only provide a reliable theoretical basis for making use of Local melon biotype but also have the significant to the future breeding work of Anhui province.The main results showed:1.Using CTAB Method extract DNA from burgeon of melon,OD_260/280value of extracted DNA was 1.8～2.0 and OD_260/230was much more two by UV spectrophotometer testing.The productivity and purity extracted DNA by using CTAB matched well for the requirement of RAPD-PCR.The amplified bands are easy distinguished by agarose analysis and repetitive well.The result is reliable for RAPD-PCR use these DNA amplifying.2.Experiment was made to optimize the amplification efficiency of different amplification conditions.The parameters in RAPD reaction system were determined by orthogonal experiment:In the system of 25μl,the quantity of template DNA is 100ng, primer 0.3μM,dNTPs 0.3mM,10×PCR Buffer 2.5μl,MgCl₂ 3mM;Taq polymerase 1.0U.3.The genomic DNAs of thirty biotypes were amplified by RAPD analysis using sixteen primers arbitrary primers screened from 60 ones.Sixteen primers amplified 134 DNA bands which hailed from thirty cultivars(Lines),114 polymorphic locus were produced, percentage of polymorphic loci was 85.07%.Every primer amplified an average of 8.4 bands,which concluded 1.3 single locus and 7.1 polymorphic locus.The average locus were four to twelve,molecular weigh of locus ranged from 100～3000.4.The cluster analysis indicated that thirty melon cultivars were classified into two group in the threshold of 0.21distance:thick melon group and thin melon group.The relationship of both melon group were far.The genetic diversity between colony indicate that Nei is 0.2638 and Shannon is 0.4036 use the popgene31 analysis.On the whole,the result of classification was conformed by using two different arithmetic computer the distance and two different software(MEGA3.1 and SPSS10.0).