Abstract:Mangifera indica germplasm resources serve as the foundation for mango breeding and are of great significance for the development of new varieties and the conservation of genetic diversity. The genetic diversity and cluster analysis on 128 mango germplasm resources preserved in the Yunnan Innovation Base for Mango Germplasm Resources Conservation of Ministry of Agriculture and Rural Affairs were studied by using amplified fragment length polymorphism (AFLP) technology. Five highly polymorphic primer pairs were selected from 64 pairs for fluorescence AFLP detection, and a total of 255 loci were identified, among which 245 were polymorphic loci, with a polymorphism rate of 96.08%. Genetic parameter calculations for all loci revealed an average observed allele number of 1.967 3, an average effective allele number of 1.573 3, an average Nei’s gene diversity index of 0.345 8, and an average Shannon’s diversity index of 0.517 9, indicating that the 128 germ- plasm resources possess rich genetic diversity. Based on the genetic similarity coefficient, cluster analysis divided the 128 germplasm resources into three major categories at a genetic similarity coefficient of 0.77. The first category included 95 resources, the second category 24 resources, and the third category 9 resources. Moreover, there was a phenomenon of cross-clustering among germplasm resources of different pedigrees. Furthermore, high genetic similarity was detected between unknown59 and Purple Flower Mango, Creamy Fragrant Mango and unknown27, as well as unknown10 and unknown25. These would provide an important basis for the selection and utilization of mango germplasm in the future, and offer scientific references for genetic breeding, germplasm conservation, and sustainable use of mango resources.
