主成分分析不同浓度CaCl2对NaCl胁迫下‘达米娜’葡萄的缓解效应

Principal component analysis on the alleviating effects of different concentrations of CaCl_2 on ‘Tamina' grape under NaCl stress

为探讨钙对葡萄盐害的缓解效应,研究了200 mmol·L^(-1) NaCl胁迫下,不同浓度CaCl_2对‘达米娜’葡萄沙培一年生自根苗的影响。结果显示:NaCl胁迫下,‘达米娜’葡萄根系、叶片相对电导率、叶片超氧阴离子自由基(O_2ˉ·)产生速率和过氧化氢(H_2O_2)含量显著升高,而超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性显著降低,新梢长度和总生物量显著降低。5和10 mmol·L^(-1) CaCl_2显著降低了NaCl胁迫下根系、叶片相对电导率、叶片O_2ˉ·产生速率和H_2O_2含量。CaCl_2显著缓解了NaCl胁迫下SOD和CAT活性的下降,15 mmol·L^(-1) CaCl_2显著缓解了POD活性的下降,而10、15和20 mmol·L^(-1) CaCl_2显著缓解了APX活性的下降。高浓度(25 mmol·L^(-1))CaCl_2处理的叶片相对电导率、O_2ˉ·产生速率和H_2O_2含量显著高于NaCl胁迫的,而POD、APX活性、新梢长和植株总生物量与NaCl胁迫的差异不显著。主成分分析表明10 mmol·L^(-1)是CaCl_2缓解200 mmol·L^(-1) NaCl胁迫对‘达米娜’葡萄的最适浓度,可能与叶片中较高的抗氧化酶活性和较少的活性氧积累有关。

This study aimed to study the alleviating effects of calcium on grape under salt stress.The annual of grapes（Vitis vinifera L.‘Tamina’）grown on the sand were the experimental materials.Then the effects of different CaCl2 concentrations on physiological properties of grape seedling were studied under 200 mmol·L^-1NaCl stress.The results showed that,under 200 mmol·L^-1 NaCl stress,the relative conductivity of roots and leaves,O2ˉ·production rate,H2O2 content of grape leaves increased significantly,while the SOD,CAT,POD,APX activities of grape leaves,shoot length and total plant biomass decreased significantly.Compared with the NaCl stress,5 and 10 mmol·L^-1 CaCl2 significantly decreased the relative conductivity of roots and leaves,O2ˉ·production rate,H2O2 content of grape leaves.Exogenous CaCl2 significantly alleviated the decrease of SOD and CAT activity under NaCl stress,15 mmol·L^-1 CaCl2 significantly increased the POD activity,while 10,15and 20 mmol·L^-1 CaCl2 significantly increased the APX activity under NaCl stress.Under high concentration（25 mmol·L^-1）of CaCl2 treatment,the relative conductivity,O2ˉ·production rate,H2O2 content of grape leaves were significantly higher than those of NaCl stress.However,there were no significant differences in the POD and APX activities,shoot length and total plant biomass between the treatment and NaCl stress.Principal component analysis results showed that the 10 mmol·L^-1 was the appropriate concentration of CaCl2 which relieving the damage of 200 mmol·L^-1 NaCl on grapes,that might be related with the higher activities of antioxidant enzymes and less accumulation of reactive oxygen species.