Studies On The Genetic Relationships Of Apricot Species By ISSR, SSR Markers

The apricot belongs to the stone fruit. It is originally produced in China and gerplasm resources are extremely rich. Many studies have been done on phenotypic observations,evaluation of palynology and isozymes. Recently, Molecular markers especially RAPD markers have been used on the genetic relationships of apricot species. It is poor that studies genetic relationships of apricot by other markers such as ISSR,SSR. This research is"Studies on the phylogenetic relationships of apricot species by ISSR, SSR Markers", which is for the purpose to carry out the apricot's species and their genetic relationships and the classified status from the DNA level, through the ISSR and SSR analyzed on the main kind of DNA gene groups of 30 gerplasm resources of the apricot, as well to establish DNA fingerprint atlas and identifying the germplasm resources to discriminate duplicated or mislabelled collections, evaluating the diversity to facilitate using in breeding and further collection and analysing the genetic relationship of apricot species. Meanwhile, the study also carries on the exploration to the kernel-used apricots' origination. Main conclusions are educed as below through the experiment.(1) ISSR optimization reacting system of The apricot category: When the bulk volume is 20μl, the DNA template measures 200ng; primer density 0.2μM, 10×buffer(20mM MgSO₄, 100mMKCl, 80mM(NH4) SO₄,100mMTris-HCl, 0.5%NP-40, pH9.0) 2μl, dNTP200μM, Taq polymerase 2U, best annealing temperature 52℃.(2) SSR marker may have the currency among the different breeds even also the different categories. In this experiment, we screen out 22 pairs from 108 pairs of SSR primers which are developed from the peaches and the cherries: BPPCT009, BPPCT020, BPPCT022, BPPCT033, BPPCT040,CPPCT6, CPPCT7, CPPCT8, CPPCT10, CPPCT14, CPPCT15, CPPCT16, CPPCT28,CPPCT30, CPPCT31, UDP96-010, UDP96-015, UDP96-019, UDP94-402,UDP98-406, UDP98-408, PS08E08. These primers can be directly applied to the SSR analysis of the apricot breeds and the variety.(3) ISSR, SSR marker researches of 30 varieties of the apricot category plants are used clustering analysis method and the host coordinates analysis method.ISSR marker analysis results:Clustering results divide the apricot category plants used in the experiments into 9 big groups: The groupâ… includes all varieties of Armeniaca vulgaris and a A. sibirica variety—Honghuashanxing; The groupâ…¡separately converges a group for A.holosericea; The groupâ…¢includes all varieties of the kernel-used apricots; The groupâ…£is A. sibirica variety which includes A. sibirica var.sibirica, dashanxing and A. sibirica var. pubescens Kost; The groupâ…¤separately converges a group for A. mandshurica; The groupâ…¥is the hongmeixing, one kind of A. limeixing; The groupâ…¦is A. dasycarpa; The groupâ…§is the varieties of the A. limeixing including the taianxingmei, limixing, and changlixingmei; The group DC separately converges a group—songchun.The main coordinates analysis results divide the apricot category plants used in the experiments into 3 groups: according to their distributions in the coordinates map, the kernel-used apricot is marked off as one group; The A. limeixing's several varieties, A. dasycarpa, songchun is divided into one group; Armeniaca vulgaris, A. sibirica,A. mandshurica,A. holosericea gather at a region, so they are divided into one group.SSR marker result analysis:Clustering results divide the apricot category plants used in the experiments into 9 big groups: The groupâ… includes four varieties of Armeniaca vulgaris, Luotuohuangxing, Huaxianjiexing, A. vulgaris var. meixianensis, Chuanzhihong and a variety of kernel-used apricot 80D05; The groupâ…¡includes all varieties of A. sibirica and kernel-used apricot except 80D05; The groupâ…¢separately converges a group for A. mandshurica; The groupâ…£includes Kezikeximixixing and the A. holosericea; The groupâ…¤is Hongmeixing which is one variety of A. limeixing; The groupâ…¥is songchun; The groupâ…¦includes A. limeixing's two breeds—Tai'anxingmei, Limixing; The groupâ…§is the Changli-xingmei which is also belong to A. limeixing; The groupâ…¨is A.dasycarpa, a single variety.The main coordinates analysis results shows that, Armeniaca vulgaris, A. sibirica, A. mandshurica and A. holosericea gather at the first quadrant, what is different with the ISSR main coordinates analysis results, one A.limeixing variety-hongmeixing(14) also gathers here; 13 kernel-used apricots distribute gradually from the first quadrant to the second quadrant, 3 kernel-used apricot distribute among above varieties' periphery, but 6 kernel-used apricot completely distribute in the second quadrant, other kernel-used apricots are situated between the two; A. limeixing variety: Tai'anxingmei(15), Limixing(16), Changlixingmei(17) and all varieties of A. dasycarpa and songchun gathers at the third quadrant.(4) The SSR marker clustering analysis results show that, the similarity factor for the oil kernel to the genetic distance is 0, and to the DNA molecule level, they are the same thing but the different names. But the ISSR mark analysis results have not educed this conclusion.(5) C210-5 is the variety gotten from Longwangmaoxing through the clone choice method. Through the SSR-PCR method, the experiment has proven C210-5 may be taken as an independent species to be named. (6) About the kernel-used apricot's origin, Experiment has used ISSR and SSR, the two testing methods, to carry on the analysis and educed the different conclusion: The ISSR method showed that the kernel-used apricot relates nearer with the ordinary apricot; The SSR method show that the kernel-used apricot relates nearer with the Siberian apricot. It needs further studies to find out the reasons of the different results through the two methods. Through the main coordinates analysis results.