Study On Evaluation Of Germplasm And Rapid Propagation In Dioscorea Opposita Thunb.

Dioscorea opposita Thunb.,commonly known as Chinese yam, which is the a winding vine, ranks in the genus of Dioscoreaceae. It has great edible and officinal value and is one of the famous Huai-Herbs. In this study,154 Dioscorea opposita Thunb. germplasms from Guangdong, Guangxi, Yunnan,Jiangxi, Henan Hainan, Fujian Provinces were involved. Morphological markers and RAPD molecular markers were used to evaluate their germplasm resources;The establishment of tissue culture was studied using No.13 Dioscorea opposita Thunb. germplasm from Bayi, Hainan as material system.1,Agronomic traits of Chinese yam and classified summary analysis of agronomic traits of a difference was not significant indicators of the material classified as a group,The result can be summarised as follows:①ased on the size of the leaves can be divided into 3 groups,large (100-160cm2), in (50.-99 cm2), small (< 50cm2)②thorns on the basis of stem whether or not divided into two groups;③phyllotaxy based, can be divided into opposite, alternate and opposite alternate;④the basis of the availability of stem edges and corners are divided into two groups;⑤on base flowering whether or not divided into two groups;⑥to the bulbil whether or not divided into two groups;⑦based on the shape of underground tubers, can be divided into strips, rod, column 3 months group.2,Using 10 primers from RAPD primers were amplified for 154samples with Dioscorea opposita Thunb.,and a total of 87 sites are amplified,of which polymorphic sites was 82, the Percentage of polymorphism equaled 94.3%.。The coefficient was separately worked out for indicators of these seven agronomic traits and results of RAPD by using SAS and NTSYS software. The result of genetic similarity analysis for 154 samples Dioscorea opposita Thunb. showed that the coefficient of agronomic traits markers and RAPD's coefficient respectively ranged from 0 to 3.2 and from 0.56 to 0.98, suggesting that RAPDmarker were better than agronomic traits markers to analyzing the genetic diversity of Dioscorea opposita Thunb.3,The influence of different hormone 6-BA,NAA levels and sterilizing time from different Dioscorea opposita Thunb. explants was studied. The experiment show that Stems with a best time of 10 min disinfection and The best time for disinfection tip 8 mim In MS+6-BA 0.4mg/L+2,4-D 0.2 mg/L bulbil, Stems with the formation of buds growing thick and grew Well；Following the relatively good performance in culture medium was MS+6.BA 0.5 mg/L+NAA 0.2mg/L+0.8%agar+3% sucrose,l Germination rate can reach 85%,Bud of each segment,the average number of up to 3.3,And better growth status.Rooting medium group is MS+6-BA 0.5mg/L +NAA 0.3mg/L+0.8% agarose+3%sucrose.Cultured 31 days,rooting was 100%, compared with thick root...