The Cold Resistance Evaluation Of Xinjiang Bermudagrass

This study took 112 idioplasm resources of Xinjiang Bermudagrass as materials. The materials were classified as three kinds, which were strong cold resistance, middling cold resistance and cold temperature sensitive. Then selected two representational idioplasm resources in each kinds, the physiological response of six materials were studied in artificial and natural low temperature stress. The results showed:1. Winter survival rate reflected cold resistance of Bermudagrass directly, with natural temperature decreasing in winter, its changed range was 9.60%～93.06%. Except of Cd099, the materials derived from beyond Xinjiang can not live in winter.2. The average temperature LT50 in leaf of Bermudagrass derived from Xinjiang and beyond Xinjiang was -14.84℃and-12.31℃respectively. In general, Cold resistance capability of Bermudagrass from Xinjiang were higher than those beyond Xinjiang.3. We selected out 6 types of Bermudagrass materials based on the results of dendrogram analysis of LT50 temperature and winter survival rate, whose cold resistance were different, the strong cold resistance types were Cd039 and Cd093, middling cold resistance types were Cd039 and Cd093, cold temperature sensitive types were Cd128 and Cd147.4. EC showed"ascend-descend-ascend"trend under artificial low temperature stress. When the temperature was 0℃and -10℃,the cell of cold temperature sensitive types injured more serious than middling cold resistance and cold temperature sensitive materials. Under natural low temperature, Bermudagrass of cold temperature sensitive types took root shallow, rhizome were few and thin, and EC fluctuated sharply than strong cold resistance and middling cold resistance materials.5. The cold temperature sensitive materials tasted low temperature earlier than strong cold resistance and middling cold resistance materials. Pro content of cold temperature sensitive materials was low and fluctuated range was limited.6. The MDA content of cold temperature sensitive material Cd128 and Cd147 fluctuated strongly under artificial and nature low temperature stress, but strong cold resistance and middling cold resistance materials were steady relatively. MDA content in rhizome all kinds of Bermudagrass materials showed downtrend under artificial freeze injuring stress.7. SOD activity of cold temperature sensitive material fluctuated greatly than strong cold resistance and middling cold resistance materials under artificial and field cold temperature stress. which was more small than strong cold resistance and middling cold resistance materials under artificial freeze injuring stress. The cells of sensitive and middling cold resistance materials injured earlier than strong cold resistance materials under nature low temperature stress.8. POD activity of cold temperature sensitive materials were higher than strong cold resistance and middling cold resistance materials, it fluctuated great under artificial cold temperature stress. POD activity of cold temperature sensitive materials were lower than cold resistance materials under artificial freeze injuring stress. POD activity of cold temperature sensitive materials fluctuated great under nature low temperature stress, but the other materials fluctuated steady relatively.