红砂愈伤组织耐低温和盐胁迫的适应性

Characteristics adapting to cold and salt stresses in callus culture of Reaumuria soongorica

对荒漠植物红砂愈伤组织分别在不同低温(0℃,4℃)和不同浓度NaCl处理下细胞的相对活性、质膜透性和脂质过氧化程度、抗氧化物质黄酮类质量分数以及抗氧化系统酶活性的变化进行研究.结果表明:低温0℃,4℃处理对红砂生理变化的影响差别不大.与室温相比,红砂愈伤组织在0℃,4℃低温胁迫的48 h内敏感性较高,细胞质膜透性增大,细胞活性有所降低,H_2O_2、丙二醛(MDA)和具有抗氧化能力的花色素苷质量分数升高,抗氧化系统酶过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)活性逐渐升高,但活性均低于对照材料的,而总黄酮质量分数以及超氧化物歧化酶(SOD)和过氧化物酶(POD)活性的变化随处理时间变化不太明显.低温处理48 h后这些生理指标都趋于稳定.同时,不同浓度NaCl处理下发现红砂愈伤组织在50 mmol/L NaCl中生长最快,总黄酮质量分数随着盐浓度增加而升高.这些结果表明红砂愈伤组织具有很强的适应低温和盐胁迫的调控能力.

The study was conducted on physio-biochemical indices in callus culture of desert plant Reaumuria soongorica under cold（0℃and 4℃） and salt stresses.These indices included relative cell activity,plasma membrane permeability,level of lipid peroxidation,content of flavonoids and antioxidant system enzymes. The results showed that there were no significant different effects on physio-biochemical indices between 0℃and 4℃.The callus exhibited high sensitivity within 48 h after being treated with 0℃and 4℃compared to the controls.Within 48 h,the plasma membrane permeability increased and the relative cell activity decreased,and the contents of H_2O_2,malondialdehyde（MDA） and anthocyanin also increased.The activities of catalase and ascorbate peroxidase increased and no marked variations were observed in peroxidase and superoxide dismutase.However,these indices remained constant after treatment 48 h of 0℃and 4℃.Callus on media with different NaCl levels was found to grow quickly in 50 mmol/L NaCl.Flavonoids accumulation was observed with the increased NaCl levels.The results indicated that Reaumuria soongorica has a strong tolerance of cold and salt stresses.