Fingerprinting Of Cultivars In National Winter Rapeseed Official Trials Detected By SSR Technique

Rapeseed is a multi-purpose cash crop, which can not only meet the increasing demand for edible oil, but also play an important role to ease the energy crisis. Last three decades, the process of the breeding of hybrid rapeseed has become quicker, and the number of varieties has sharply increased, but genetic basis of most varieties is relatively narrow. The emergence and rapid development of DNA molecular markers provide us a new technology for precise identification of rapeseed varieties. In this study, new winter rapeseed cultivars in the national field tests are analyzed by fingerprint during the 2007-2008,2008-2009 and 2009-2010. The results are as follows:1. In this study,74 SSR markers developed from EST sequences and 148 pair of primers from Wang Tonghua (2007) and Yang jun (2009) are filtered for core primers. Finally,21 pair of core primers with stability, repetition and clear amplification are filtered and the PCR reaction system and conditions are also optimized. Annealing temperature and primer concentration are found to effect amplification greatly. The 21 pair of primers’concentration fluctuate between 0.15 and 0.4 umol/L, and annealing temperature fluctuate between 55℃-61℃. Using extensive-polymorphic SSR primers to do PCR amplification in two different amplification systems. Then doing electrophoresis on 3% agarose gel and 6% polyacrylamide gel respectively to compare and analyze the both amplication influence. The result show that resolution of 3% agarose gel electrophoresis is lower, so it can not make fingerprint analysis instead of 6% polyacrylamide gel electrophoresis.2. By the screening primers, optimized PCR reaction system and conditions,106 materials from 2007-2008,164 materials from 2008-2009 and 168 materials from 2009-2010 were analyzed by fingerprint. Such rule was found that the lines with close genetic distance are usually derived from the same unit. For example, sunshine 198 and sunshine2009 come from; sunshine epoch seed company; C922 and C868 come from Hunan crop institute. There are two qinyou7 lines in the national field tests during 2009-2010, which are completely overlapping in the clustering result. Analyzing the yearly clustering results by dividing regions, there was not apparent relationship between genetic distance and lines’origin.