Evaluation Of Biological Characters And Analysis On Genetic Relationship Of 66 Mango Germplasm Resources By ISSR Markers

In this study, Hainan, Yunnan and Guangxi mango germplasm survey, collecting more than 20 wild and semi-wild and local varieties of mango germplasm and stored in the Ministry of Agriculture Danzhou mango germplasm nursery, completing 66 of wild. Semi-wild, local varieties and cultivars of mango gemiplasm evaluation of the traits described, while the use of ISSR molecular markers, genomic DNA from the level of the germplasm of clustering and phylogenetic analysis, the main results are as follows:One, In reference to the mango germplasm resources formulated descriptor or standard established by Chen Yeyuan, UPOV, IPGRI, also on the basis of the reality, the Angle of the mango main branch and the trunk and so on. A total of 22 major biological indicators were analyzed and evaluated, found that its has rich diversity. Furthermore,18 indicators of them were graded or classified. In allied species and wild type, observed that BianTao mango, wild mango 1. ChangJiang 002 are extremly different from ordinary mango. Main performances: the blade of BianTao mango is narrow lanceolate, leaf shape index is large; and the blade of wild mango 1 is loval lanceolate and long oval with long, very wide blade and small leaf shape index; But the blade of ChangJiang 002 is long, very broad, and leaf index is small.Two, using orthogonal design, single factor design the mango ISSR reaction system was established. The best reaction system:the total system for 25μl, contains 10 x buffer 2.5μl, template DNA 25ng, dNTPs 0.3 mmol·1-1, Mg2+2.0 mmol·1-1, primer 0.32μmol·1-1 and Taq enzyme 1.25 U. By using the optimized reaction system screened 20 suitable primers for mango ISSR analysis.Three. Using primers screened 66 mango germplasm phylogenetic study was done.166 polymorphic bands were generated totally with an average 8.3 bands per primer. The percentage of polymorphic bands (PPB) was 95.0%. The genetic similarity coefficient amomg germplasm is 0.395-0.882 with the average 0.627. After cluster analysis using the NTSYSpc 2.1 Oe software, the results show that the genetic relationship between the JinSui and NaPo 001 is near, while it is the farthest between GuangXi TuMang and Kyo Savoy.Four. Based on clustering figure and the genetic similarity coefficient between germplasm analysis,66 mango germplasm resources can be separated fundamentally. Taking the similarity coefficient 0.66 for threshold.66 selected germplasm can be divided into 12 groups; while taking the similarity coefficient 0.72 for threshold, the first group of germplasm can be divided into eight groups again.Five. The clustering results showed that the wild mango germplasm resources covered various groups of wild germplasm. semi-wild species exist in a few groups, while the cultivated germplasm almost all concentrated in the same group, the genetic similarity coefficient became smaller, which indicated that the genotypes gradually moved towards single, at the same time, the level of genetic diversity also gradually reduced from the wild. semi-wild to cultivated mango.