Abstract:

Arecanut (Areca catechu L.) is an important tropical economic and social importance plant in Hainan Province. It has high medicinal value and is listed as the first of the four south China medicinal plants. Areca is mostly planted in underdeveloped areas, and the basic research is weak. The germplasm diversity of areca from Hainan remains unclear due to lack of systemic research of germplasm. We analyzed the genetic diversity among 58 arecanut accessions from Hainan by SSR molecular marker technology to clarify the genetic relationship and provide a theoretical basis for the hybrid breeding and functional gene mining. The results showed that 32 primers with high polymorphism and clear bands were screened out from 500 SSR primers. A total of 79 alleles were detected from the 58 arecanut germplasm resources, and there were 2-5 loci per SSR, with an average of 2.4688 alleles at each marker, and the number of effective allele was accounted for 58.92% of the observed one. The range of PIC was 0.0169-0.5969, with an average of 0.2254. The Shannon index (I) of all primers ranged from 0.0496 to 1.2552, with an average of 0.4496. Nei’s genetic diversity index (Nei) was ranged from 0.0171 to 0.6492, with an average of 0.2596. The genetic diversity of alleles detected by SSR primers was low. UPGMA Cluster analysis showed that the genetic diversity of group V was the richest. Genetic analysis showed that the 58 arecanut were separated from the effect of regional isolation. The conclusion of frequent exchanges among different regions of arecanut in Hainan and lower genetic diversity in Hainan cultivars would provide theoretical guidance for the selection of parents in the genetic breeding of arecanut, while reference for collecting germplasm to supplement different resources in the future.

Key words: arecanut, SSR markers, clustering analysis, genetic diversity