Identification Of Cold-Resistance In Cabbage And Screening Of Germplasm Resources

In the background of global warming climate, extreme weather events increase in frequency and intensity. The weather phenomenons such as Spring temperature rising slowly and Autumn coming early have became the main difficult problem for the production of cabbage vegetables. Thus, we need some cold hardiness of cabbage varieties to solve this problem, and it becomes a great significance for cold hardiness cabbage varieties breeding to set up a relatively complete identification system for cold resistance germplasm resources.12varieties of cabbage breeding material as the research object, have been studied in three parts, First, we investigated the germination performances of cabbage seeds under the temperature gradient20,15,10,5.Then, the cabbage seedlings to study the Morphological indicators and the change rule of several physiological and biochemical indexes and find out some simple, rapid and effective appraisal indicators. Finally, the content of anthocyanins in cold resistance varieties were determined and analyze these indicators measuring the correlation between these12inbred lines of cold judgment. The main results of experiment were as follows:1.With the treatment time of lower temperature prolonged,12inbred lines of cabbage seedlings in conductivity levels continue to rise, and the difference in conductivity between different inbred lines was very significant, it could be one of the index to appraise cold-resistance of cabbage at the seedling stage.2.With the treatment time of lower temperature prolonged,12Cabbage inbred with the extension of the body the content of soluble sugars^protein and proline cryogenic during seedling stage were all appeared the tendency of raising at first and then declining, and between different inbred lines they have reached a significant difference, so the content of osmotic adjustment substances of cabbage seeding’s leaves after low temperature treatment could act as appraisal index of cold-resistance of cabbage.3.low temperature stress cabbage leaves SOD、POD activity and the content of MDA, significant differences between inbred lines, indicating that the changes in their obvious differences, it could be one of the index to appraise cold-resistance of cabbage at the seedling stage.4.After the low temperature stress,morphological index and biological yield during cabbage seedlings stage were all appeared the tendency of declining, while the root activity were rising, and the significant differences between different inbred lines, so it could be identified as cold-resistance of cabbage reference index. 5. The correlation analysis shows that we can change the conductivity and MDA content of hardy germplasm screening method is simple.Through comparative analysis, as seed germination, the methods of Electric conductivity percentage were simple and easy to operate, less necessary equipment, suitable for mass identification and screening germplasm resources. In this experiment, the analysis of germination, seedling and mature period on a number of indicators,the test material was divided into three groups:High cold-resistance materials:2-1002、2-1001、2-1011、P3、2-1015、8-1005;Moderately cold-resistant:8398、R、0-1012;Low temperature sensitive materials:Q4、 Q2、Jingfeng.