Genetic Relationship Analysis Of Apple Cultivars Using SSR And SRAP Markers

Apple (Malus domestica Borkh.) is one of the most important temperate deciduous fruit trees. It was cultivated from long time ago and apple is of wide distribution. How to make use of the genetic diversity of apple cultivation to breed new varieties has been paied much attention in the traditional breeding method. In order to select the proper parents in apple breeding which are with less similarity in genetic material. The genetic relationship of 37 apple cultivars have been studied by the SSR and SRAP markers. The results as following:(1)By using a new type of reagent named Taq Master Mix which is a kind of mixture of Taq Polymerase, dNTPs and Mg2+ . The degrading has been prevented during operation. SSR-PCR system: 50ng genomie DNA, prime(r10μmol/L)1μL, Taq Master Mix:10μL. Total volume is 20μL, the rest volume is filled with ddH2O. SRAP-PCR system: 50 ng genomie DNA 2μL. Primer(10μmol/L)1μL, Taq Master Mix:10μL. Total volume is 25μL, the rest volume is filled with ddH2O.(2)56 and 64 bands were obtained by SSR and SRAP markers amplified through 10 selected primers respectively. Polymorphic percentage is 61.09 % and 70.80 %.(3)Relevance analysis of SSR and SRAP were significantly correlated shows that the datum of synthesizing SSR and SRAP can study the genetic relationship clearly.(4)Based on the SSR+SRAP results, the similarity coefficient was calculated first, then UPGMA cluster analysis were built. The result showed that the selected primers were effective in revealing genetic diversity of the tested varieties, and the apple cultivars could be classified into the six groups , which were similar to the traditional classification. GroupⅠinclude 27 cultivars: Golden Delicious, Mutsu, Toko, Huaguan, Jonagold, Yanguang, Danxia,Qinyang, Orin ,Pimklady , Cox's orange are in A subclass . Fuji , Ralls, Hongbaoshi , HAC9 , Delicious , Starkrimson, Qiujin Sekaiichi, Qinxing , Yueshuai, Kuihua , Megumi , Yanfeng , Shinsekai, Qianqiu, Senshu are in B subclass; GroupⅡinclude 2 varieties Empire and McIntosh; GroupⅢinclude 4 cultivars: Royal Gala, Gala, Jinhong, Kizashi; GroupⅣandⅥinclude only 1 cultivar respectively as Indo and Jonathan while groupⅤinclude 2 cutivars: Qinguan and Jiguan.