Genetic And Variation Study To Laminaria "901" Strain

Based on the DNA extraction and optimization of random amplified reaction (RAPD) to the gametophytes and sporophytes of Laminaria "901"strain, genetic and variation study were conducted to its parents and F6, F7, F8, F9 generations' samples. By the statistics and analysis data obtained with the software process, we analyzed population genetics and the influence of parents to each generation's materials, the main conclusions are shown as follows:1. Among the 30 selected primers for the study, 297 loci ranging from 200 to 3000 bp were obtained and, the average is 9.9 bands for each primer. This indicated the high polymorphic rate with RAPD detection. UPGMA analysis showed that each male and female gametophyte in one generation could be clustered into one pair respectively. The genetic distances to each generation are 0.3212-0.4767, and the maximum is between F7 to F8 (0.4767). Identity analysis indicated that F6 generation is inherited mostly from the female parent (0.6593), and F7 generation is mostly from the male parent (0.5788).2. Population genetic study revealed that, of the 24 selected primers for the RAPD amplification, 206 loci ranging from 230-2800 bp were obtained, and the average to each primer is 8.6 bands. The mean percentages of polymorphic loci to the five populations tested were male parent (0.2272), F6 (0.2017), F7 (0.2190), F8 (0.2181), F9 (0.2953). The nearest genetic distance is 0.00812 (F8, F9) and the second one is 0.1065 (F6, F7). Comparatively, the genetic distance between male parent to all the generations is not close. Taking the F6, F7, F8, F9 as a whole population, Gst of the F6, F7, F8, F9 generations is 0.2936, this implied that divergent rate is 29.36 % in the four sub-populations.3. Six SCAR (sequence characterized amplified regions) were obtained through the RAPD analysis for Laminaria "901"strain, and this is significant for molecular marker assistance in breeding and selection to Laminaria. ...