Identification Of Undaria Culture Lines And Their Genetics Background Study

The aim of this research is to apply the valid DNA fingerprint methods to identify the germplasm of Undaria culture lines, which were widely applied in the cultivation in China. Undaria is one of the three main commercial seaweeds cultivated in China. It is essential to select the strains with high quality and steady heredity in practice. In this research, all the representative cultured cell lines applied in China were chosen to analyze such as Southern Japan (U. typical) cell line, Northern Japan (U. distans) cell line, Dalian China cell line, Weihai Shandong cell line, Rongcheng Shandong cell line, Rizhao Shandong cell line and Qingdao wild type. Eleven pairs of Undaria pinnatifida gametophytes and one Laminaria japonica cell line as outgroup, were analyzed with RAPD technique. A total of 312 polymorphic loci were obtained from the 20 selected 10 base primers, of which 97.7% were polymorphic for the Undaria gametophytes. DNA fingerprints of the 22 Undaria gametophytes were constructed with seven repetitive and clear RAPD loci. After the reexamination, four SCAR markers were successfully converted from the three RAPD markers, and could be applied to Undaria germplasm identification and selection. ISSR analysis was either applied in analyzing of the gametophytes. A total of 99 polymorphic loci were obtained from the 13 selected ISSR primers. There were no obvious differences between the dendrograms constructed from the two methods. Six pairs of male and female gametophytes were clustered with RAPD analysis, and seven pairs were clustered with ISSR analysis. The yielded loci from ISSR detection were less than that of RAPD analysis, this may attributed to that all the selected gametophytes were from the same species Undaria pinnatifida, and furthermore specific ISSR primer were needed to be developed for verification of Undaria cell lines. The constructed fingerprints, SCAR markers and the ISSR markers can provide a molecular basis for Undaria selection and breeding, and will be useful in the Undaria procduction.