外源NO对采后芒果果实低温胁迫后H2O2代谢的影响

Effect of Exogenous NO on H_2O_2 Metabolism in Postharvest Mango Fruit under Low Temperature Stress

一氧化氮(NO)是植物体内重要的信号分子。为了探讨NO对采后芒果低温胁迫后果实过氧化氢(H2O2)及抗氧化酶的影响,分别采用0.08 mmol/L NO供体SNP溶液和30μL/L NO气体处理采后青芒果果实,并于3℃低温贮藏12 d后,检测芒果果皮和果肉中H2O2含量和相关抗氧化酶的活性。结果表明,外源NO浸泡处理能显著降低低温胁迫后芒果果皮中H2O2水平,提高超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性,其中NO对CAT活性的影响最大,可能是外源NO处理调控H2O2水平的关键作用点。NO供体SNP处理效果优于NO气体处理,主要作用部位为芒果果皮。

Nitric oxide （NO） is an important signal molecule in plants. In order to discuss the effect of NO on H202 level and metabolism in postharvest mango fruit under low temperature stress, 0. 08 mmoL/L NO donor SNP and 30 μL/L NO gas were used to treat green mango fruit before cold storage. H202 content and the activities of superoxide dismutase （ SOD）, catalase （ CAT）, peroxidase（POD） and aseorbate peroxidase （APX） were measured 12 d after cold storage at 3~C. The results showed that both SNP and NO gas treatments had significantly reduced H2O2 level in postharvest mango fruit pericarp, and increased the activities of SOD, CAT and POD. The effect of SNP was more significant than NO gas. The main effect site of exogenous NO was pericarp.