Abstract:

To catalogue and preserve 23 tobacco germplasm resources collected from Hainan Province, agronomic characters and genetic diversity of these tobacco germplasm resources were investigated, and the fingerprints were constructed. The results showed that the agronomic traits and qualitative traits of tested germplasms varied greatly. The coefficient of variation ranged from 20.69% to 29.41% in different agronomic traits. These collected tobacco germplasms were divided into 3 groups by clustering analysis. The germplasms from the second group were the tallest with the largest leaf, which could be used for high-yield breeding. In addition, 12 pairs of primers with specific amplification were screened from 2000 pairs of SSR primers, and 46 polymorphic bands were obtained. An average of 3.83 alleles was observed for each primer pair with the average heterozygosity (Ho) of 0.5301, and the average expected heterozygosity (He) of 0.4700. Shannon’s index was 0.8930, Nei’s index was 0.4593. The genetic diversity of the 23 tobacco germplasm resources was relatively abundant. These varieties were clustered into two groups at the genetic similarly coefficient of 0.206 by UPGMA cluster analysis. At the same time, 12 pairs of primers were used to construct the fingerprints of the 23 tobacco germplasm resources, which laid a theoretical foundation for the research on the identification system of sun-cured tobacco varieties. The study can provide reference for identification and utilization of sun-cured tobacco germplasm resources and selection of parent materials for cigar breeding.

Key words: sun-cured tobacco, germplasm resources, phenotypic traits, simple sequence repeat (SSR), genetic diversity