Analysis Of Genetic Diversity Of Asparagus (asparagus Officinalis L.)

Asparagus (Asparagus officinalis L.) is a dioecious species and a perennial crop. It seems that it has been used and cultivated as a medicinal and food plant for at least two thousand years, and has been playing an increasingly important part in agriculture since imported in 1980s. Rresearches of asparagus has been focused on strengthening the exploitation and conservation of asparagus germplasm resource, analyzing its genetic diversity, aimed at accelerating the selective cultivation of new varieties with modern biotechnology. The molecular marker realized detection of genetic diversity at DNA level. RAPD has the added advantage over other molecular markers of being relatively simple and quick to perform, and require only small quantities of DNA for analysis. As a consequence, RAPD has been widely used to identify and characterize closely related plant species and cultivars. In this paper, RAPD was used to analyze genetic polymorphisms of 43 asparagus cultivas and hybrids.The fingerprints of 43 asparagus cultivars and hybrids were generated using RAPD method. Twelve primers were screened from 60 ten-bp arbitrary primers, and a total of 183 DNA fragments were amplified, among which 170 (92.92%) were polymorphic. The average number of DNA band produced by each primer was 15. The result of genetic similarity analysis for 43 asparagus genotypes showed that the Nei's coefficient ranged from 0.407 to 0.931, and the average Nei's coefficient was 0.765, suggesting that there was a close genetic relationship between them. A DNA molecular dendrogram was established for 43 genotypes based on UPGMA cluster analysis of 183 DNA bands amplified by 12 primers, which divided them into eight groups according to coefficient 0.77. Among them, six genotypes were a group by itself, such as Jwcl, Purple Passion. And the others were divided into two groups.There are few reports about genetic relationship of asparagus on the basis of RAPD fingerprint. In this experiment, RAPD analysis revealed that there was close correlation between the origin of asparagus genotypes and groups. The average coefficient 0.781 provided the information that there was a close genetic relationship between them. These maybe rested in the origin of materials used in asparagus cultivation and breeding. We analyzed the reason and predicted the selection of parental materials for breeding. For long-term development of asparagus undertaking, we made some suggestions of protection and study on asparagus germplasm resource.