Evaluation Of Waterlogging Toierance At Different Developmental And Construction Genetic Linkage Man In Brassica Napus. L

Rapeseed is not only one of the world’s major sources of edible oil but also raw material for industrial product, so the research of rapeseed is very important. Yangtze River Valley is the biggest rapeseed production zone in China, in which rice-rapeseed crop rotation prevail. In this area, frequent seasonal rainy climate cause heavy rapeseed yield lost (almost17%-42%).Therefore, the genetic improvement of rapeseed waterlogging tolerance will be vital both for alleviation of waterlogging and exploitation of winter fallow field. To reveal the physiological mechanism of the waterlogging resistance of rapeseed, we study the different time gradient of waterlogging stress at germination stage and seedling stage by P90, and screening and identification the waterlogging resistance of rapeseed according to the waterlogging stress system. Moreover, we also constructed genetic linkage maps based on RILs lines derived from a cross of Zhongshuang9×GH01.The results are as following:1. With different methods of waterlogging stress by P90at germination stage and seedling stage, the characteristics related to waterlogging stress were investigated. The results showed that waterlogging12h at germination stage and5d at seedling stage can be used for evaluation of waterlogging resistance of rapeseed. Though membership function or tolerance index based on yield, the material can be divided into tolerance, middling and sensitive. We screened7strong waterlogging resistance material at germination stage,5strong waterlogging resistance material at seedling stage and3strong waterlogging resistance material at field experiment. In25material, there are3sensitive and5middling in three periods, these materials which are the same tolerance resistance at the different periods, suggest that there are a common mechanism of waterlogging resistance in this material, makes the performance the same resistance in different periods.Correlation analysis showed that the shoot length index, fresh weight index and root length index at the germination stage and root length index,shoot length index and full length index at seedling stage and yield index has signification correlation, so the germination stage and seedling stage can evaluation the tolerance at the yield waterlogging tolerance.We evaluated the testing methods to waterlogging tolerance at different growth stages.2. We constructed genetic linkage maps based on RILs lines derived from a cross of Zhongshuang9×GH01.912pairs of SSR markers and42pairs of SRAP markers were screened in parents, the result show that SSR polymorphism proportion is19.07%and the SRAP is64.29%. We choose good polymorphism153SSR and2SRAP markers amplification, and get172SSR banding and4SRAP banding.The Jion map was used to construct genetic linkage map, a middle-density genetic linkage maps of rapeseed with19groups was constructed by147SSR marker loci and3SRAP maker loci, which covered1409.1cM and the average interval was9.64cM.