霜疫病菌侵染对荔枝果实生理变化的影响

Effects of Peronophythora litchi Infection on Physiological Changes of Litchi Fruit

测定了荔枝果实人工接种霜疫病菌后呼吸速率、乙烯释放量的变化和果皮中氧化、过氧化作用以及与酚类氧化有关的几种酶活性的变化。结果表明,接种霜疫病菌的荔枝果实呼吸速率和乙烯释放量显著增高,果皮中活性氧(O2-)产生速率和膜脂过氧化产物丙二醛(MDA)含量增加,超氧化物歧化酶(SOD)活性降低,过氧化物酶(POD)和多酚氧化物酶(PPO)活性增高。这是霜疫病加速采收后荔枝果实衰老、褐变、腐烂的重要原因之一。

Changes of respiration rate ,ethylene production,oxidation and peroxidation process and activities of several enzymes related to phenolic oxidation in litchi fruit after inoculated with peronophythora litchi, were determined. The results suggested that both respiration rate and ethylene production of inoculated litchi fruit enhanced significantly, the rate of superoxide radical anion （O2^-） production and lipid peroxidation rcactant-malondialdehyde （MDA） increased,the activity of superoxide dismutase （SOD） decreased while polyphenoloxidase （PPO）,pcroxidase （POD） promoted in litchi pericarp. All above indicated that the infection of peronophythora litchi could enhance respiration rate and ethylene production,accelerate the course of oxidation and peroxidation,and induce the activities of POD, PPO in litchi pericarp. So the infection of peronophythora litchi, was one of the important reasons that quickened senescence, browning and decay of litehi fruit.