【摘要】 以耐盐碱品种龙稻21和盐敏感品种乌兰105为材料，在50 mmol/L NaCl模拟盐胁迫条件下，外源施用1、5、10 mmol/L CaCl₂,筛选Ca²⁺对水稻耐盐性的最佳浓度并阐明其对水稻耐盐的缓解效应。结果表明，50 mmol/L的NaCl胁迫显著抑制了2个品种水稻种子的萌发及幼苗生长，龙稻21表现出较强的耐盐能力。不同浓度的CaCl₂处理均能在一定程度上缓解盐胁迫造成的损伤，促进发芽率、芽长和根长的提升，增强超氧化物歧化酶（SOD）、过氧化物酶（POD）与过氧化氢酶（CAT）活性，降低丙二醛（MDA）含量，其中以5 mmol/L处理的效果最为显著。在该浓度下，龙稻21的SOD、POD、CAT活性分别提升41.32%、27.04%、70.59%,MDA含量降低37.64%;乌兰105的SOD、POD、CAT活性分别提升48.00%、31.81%、72.67%,MDA含量降低36.22%。更多还原

【Abstract】 Using the salt-tolerant rice（Oryza sativa L.） variety Longdao21 and the salt-sensitive variety Wulan105 as materials, under a simulated salt stress condition of 50 mmol/L NaCl, exogenous application of 1, 5, 10 mmol/L CaCl₂ was conducted to screen the optimal concentration of Ca²⁺ for rice salt tolerance and clarify its alleviating effect on rice salt tolerance. The results showed that the 50 mmol/L salt stress significantly inhibited the germination and growth of the seeds of both varieties of rice, and Longdao21 exhibited a stronger salt tolerance. Different concentrations of CaCl₂ treatments could all to some extent alleviate the damage caused by salt stress, promote the increase of germination rate, shoot length and root length, enhance the activities of superoxide dismutase（SOD）, peroxidase（POD） and catalase（CAT）, reduce the content of malondialdehyde（MDA）, and among them, the effect of 5 mmol/L treatment was the most significant. At this concentration, the activities of SOD, POD and CAT in Longdao21 increased by 41.32%, 27.04% and 70.59%, respectively, and the content of MDA decreased by 37.64%. The activities of SOD, POD and CAT in Wulan105 increased by 48.00%, 31.81% and 72.67%, respectively, and the content of MDA decreased by 36.22%.更多还原