CDDP genetic diversity analysis of a very small population of wild plant Cypripedium palangshanense

Abstract:

Cypripedium palangshanense is a rare and endangered protected plant unique to China. It is an extremely small population of wild distributed in a narrow area. To study its genetic diversity CDDP molecular marker technology was used to evaluate the genetic diversity of 92 materials from 6 experimental sites in 2 wild populations of C. palangshanense in Wolong and Wanglang Nature Reserves, and further explore the relationship between genetic diversity and environmental factors. The results of the genetic analysis showed that a total of 131 locus were detected at the species level with 12 primers, the percentage of polymorphic loci (PPL) was 100%, the observed allele (Na) was 2, the effective allele (Ne) was 1.5026, the Nei′s genetic diversity index (H) was 0.3141, and the Shannon diversity index (I) was 0.4856; At the population level, the genetic diversity of Wolong population was higher than that of Wanglang population, and the variation range of Na was 1.4504 ~ 1.9160; the variation range of Ne was 1.2446 ~ 1.4336; H was between 0.1464 and 0.2679; I was between 0.2231 and 0.4153; the variation range of PPL was 45.04% ~ 91.60%. The genetic differentiation coefficient (Gst) of C. palangshanense was 02863. The genetic structure and AMOVA analysis showed that there was genetic differentiation among the populations of C. palangshanense. Mantel test showed that there was a significant correlation between genetic distance and geographical distance among Cypripedium palang shanense populations in Balang mountain (R2 = 0.3830, P<0.05). According to UPGMA cluster analysis, Wolong population and Wanglang population are clustered into one branch. The correlation analysis between genetic diversity and environmental factors showed that there was a significant positive correlation among observed allele (Na), the number of polymorphic loci (Np), percentage of polymorphic loci (PPL) and available potassium content (AK); The number of effective alleles (Ne), Nei′s genetic diversity index (H) and Shannon information index (I) were significantly positively correlated with altitude (Alt); There was no significant correlation between remaining environmental factors and genetic diversity index. The results showed that CDDP molecular markers technology was suitable for the study of the genetic diversity of C. palangshanense, and was highly polymorphic.