施硒对樱桃番茄贮藏品质及3种活性氧代谢酶的影响

Effects of Selenium on Cherry Tomato Storage Qualities and Involved Three Active Oxygen Metabolism Related Enzymes

为探寻施硒对樱桃番茄采后贮藏品质的影响并确定其适宜的处理浓度,在樱桃番茄发育过程中分次冲施不同浓度硒肥,分析番茄果实采收时及在贮藏过程中果实硬度、色泽、乙烯释放量、糖、酸、V_C含量及活性氧代谢相关酶活性的变化情况。结果表明,采收时2 mg/L硒处理的樱桃番茄果实硬度、可溶性糖含量、V_C含量与对照组相比分别增加了7.98%、5.29%和11.32%,并在贮藏过程中始终维持较高含量;同时2 mg/L硒处理提高了采后果实过氧化物酶活性(40.01~64.24 U/g)和超氧化物歧化酶活性(36.94~186.39 U/g);并在乙烯释放高峰时期(21 d)抑制乙烯释放量至8.01μL/kg·h,延缓了樱桃番茄果实的采后衰老。而3 mg/L硒处理在贮藏42 d时对果实的活性氧代谢酶表现出负面影响,过氧化氢酶、过氧化物酶、超氧化物歧化酶活性分别低于对照组11.93%、23.09%和31.01%,不利于维持番茄果实的贮藏品质。2 mg/L为适宜的采前硒处理浓度,可以提升樱桃番茄果实品质及贮藏特性。

In order to explore the effect of selenium on the qualities of postharvest cherry tomatoes and find the proper concentration,selenium with various concentrations were applied to the soil at several stage during cherry tomato development. Then the fruit qualities including fruit firmness,color,soluble sugar,acid,V_C and active oxygen metabolism related enzymes at harvest and during storage were analyzed. The results showed that,the contents of fruit firmness,soluble sugar and V_C of 2 mg/L selenium applied tomato fruits increased by 7.98%,5.29% and 11.32% compared with that of control group at harvest,respectively. During postharvest storage,2 mg/L selenium treatment could maintain better fruit qualities,promote the activities of peroxidase(40.01~64.24 U/g)and superoxide dismutase(36.94~186.39 U/g),decreasd ethylene evolution rate to 8.01 μL/kg·h at 21 d,and then postpone the fruit senescence. However,higher concentration of selenium treatment(3 mg/L)had negative effects on the active oxygen metabolism related enzymes at later storage stage and was not satisfactory for maintaining cherry tomato qualities. The activities of catalase,peroxidase and superoxide dismutase decreased by 11.93%,23.09% and 31.01% than control at day 42,respectively. 2 mg/L concentration of selenium could be applied to promote the qualities of cherry tomato fruits at harvest and during postharvest storage.