Analysis On The Diversity Of Genetic Of Betaphycus Gelatinum Among Farmed And Wild Population Based On EST-SSR

Betaphycus gelatinum is one of the major cultivation objects in the production of carrageenan, simple vegetative propagation lead to the degradation of germplasm. The impact of water quality, light, temperature, etc., can lead to the same species have different color, it makes people mistaken it is different algae. The early classification of Eucheuma is confusion, different species product different type of carrageenan, the confusion of classification can affect the adhesive quality and strength. Factors above caused some affect in the carrageenan production. As the view of the above investigation, in order to solve these problems, EST-SSR method was used by this laboratory to get spreliminary judgment of its classification and identification, it had provide some theoretical basis on phyletic evolution, genetic diversity, breeding and seed select of Betaphycus gelatinum.First,1459EST sequences were downloaded from GenBank:5Betaphycus,454Kappaphycus,1000Eucheuma. Then search the SSR from1459EST sequences of Eucheuma, derived a total of56SSRs included in the47EST sequences. After that,28pairs of primers designed by using the Primer Premier5.0software,5primers was select out as its good at RBPD and repeatability.25locus detected from the amplified product, the stripe size between80bp-1.5kb, there was17polymorphic loci, the average percentage of polymorphic loci was68%. Finally, the data was analysised by using the NTSYS software, the results show that, the four geographical groups has the percentage of polymorphic loci varied from33.3%to80%, genetic similarity coefficients ranged from0.51-0.80, the variation of genetic distance0.20-0.49. Using NTSYS software on UPGMA cluster analysis to the four geographical groups, Area B (Wenchang1) and area C (Wenchang2) had the highest genetic similarity coefficient of0.80, area A (Dongfang) and the other three locations had the lowest genetic similarity coefficients of0.51, area D (Qionghai) and area AB clustering around0.70. Population genetic clustering diagram constructed accordance the similarity coefficient by UPGMA method directly reflect the relationship between the four locations. It can be seen that as the geographic point closer the genetic differences is also smaller.In this study, the relationships between Betaphycus gelatinum differences and geographical may be due to sexual reproduction rely on ocean currents. In ports as well as human activities, pollution would be detrimental to Betaphycus gelatinum growth, these areas have been divided into relatively independent coast. The two locations in Wenchang region has no large port to make it separated, but locations in Qionghai have a Qinglan port makes it apart.The three point in a nature reserve of eastern Hainan which sampling of product differences is less than the difference in the point of the western culture zone, may have the following two cases. First one is that, the Eucheuma gelatinae in the culture zone not introduction from east waters of Hainan, the variation difference is purely relative due to the geographical isolation between the east and west; Second, as the long-term asexual reproduction of western culture zone, resulting in the degradation of germplasm resources, genetic drift, the loss of certain genes, thus makes diversity reduced.