Abstract:

Genetic diversity and population structure of 95 local cultivars of Chinese chestnut （Castanea mollissima BL.）from 10 provinces，such as Shandong etc.，were analyzed using SSR markers，and association analysis was conducted with 18 agronomic traits，all of these laid the theoretical basis for rational use and protection of the germplasm resources，and molecular marker-assisted breeding of Chinese chestnut. The results showed：（1）Forty-four allelic loci were detected from 95 chestnut cultivars in 17 SSR markers，the average was 2.6，and the mean of Shannon’s index（I）and polymorphism information content （PIC）were 0.67 and 0.352，respectively，which reveal that the genetic diversity were abundant；（2）Percentage of polymorphic loci of Shandong and Jiangsu population reach the highest of 94.12%，and observed number of alleles（Na）of them were 2.53 and 2.18，respectively，which also higher than the other provinces，indicated that genetic diversity of them were higher than the other provinces；（3）Ninety-two chestnut cultivars were divided into three subgroups based on statistical model of Evanno etc.，the three subgroups contain 25，40 and 27 cultivars，respectively，and their geographical origin were highly complexly，however，the other three cultivars were clearly not assigned to any subgroup；（4）Petiole length and starch cotent were significantly associated with CsCAT5 and CsCAT22 markers after a false positive test by using GLM and MLM models，and their association coefficient were 0.4027 and 0.1869，repectively.

Key words: Chinese chestnut, SSR, genetic diversity, population structure, association analysis