Evaluation of cold and drought resistance of four cypress provenances
Some 2-year-old Cupressus funebris seedlings from four different provenances (Sichuan Santai,Hubei Jingshan,Chongqing Youyang,and Zhejiang Kaihua) were adopted as the materials in the present study to evaluate their cold and drought tolerance by low-temperature and drought stress treatments,respectively.Under the stress treatment,the morphology,relative and absolute water content,relative membrane permeability,photo-synthetic pigment content,malondialdehyde content,and proline content of the needles were investigated,respec-tively,and based on the membership function analysis,the cold and drought resistance of the four provenances were evaluated.The results showed that:(1) Under low-temperature treatment,the relative membrane permeabil-ity of all plants increased obviously with the decrease of temperature;the content of chlorophyll decreased signif-icantly,while the carotenoid content changed indistinctively;the content of malondialdehyde and proline in-creased significantly.The response and tolerance of the four provenances to low-temperature stress were different remarkably,and their cold resistance ranked as:Zhejiang Kaihua>Sichuan Santai>Chongqing Youyang>Hubei Jingshan.(2) Drought stress decreased the plant growth and caused obvious water-loss symptoms.After drought treatment for 30 days,the relative membrane permeability and malondialdehyde content in the needles increased significantly,coupled with significantly decreased photosynthetic pigment content,and their values recovered to the control level after 10-day rehydration;the proline content increased significantly as well,but it did not reach the control level at the end of the experiment.The response and tolerance of the four provenances to drought stress were different obviously,and the order of drought resistance of the four provenances was:Chongqing Youyang>Si-chuan Santai>Hubei Jingshan>Zhejiang Kaihua.
万方数据
维普
