酶活性、丙二醛含量变化与豇豆抗枯萎病的关系

以豇豆抗病品种丰产二号和感病品种之豇28-2为试材,对接种枯萎病菌后2、4、6、8、10 d幼苗叶片的多酚氧化酶(PPO)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、过氧化氢酶(CAT)、几丁质酶(chitinase)、β-1,3-葡聚糖酶活性及丙二醛(MDA)含量的变化进行分析.结果表明:1) 未接种枯萎病菌的抗、感品种酶活性与MDA含量均无明显差异.2) 接种后,抗、感品种酶活性与MDA含量都呈升高趋势,抗病品种的酶活性升高幅度大于感病品种,抗病品种PPO、CAT活性与MDA含量始终高于感病品种.3) 接种后,抗病品种PPO、POD、CAT、几丁质酶活性升高比感病品种早,可能是它们可以较早启动抗病性反应.

MDA content and enzymatic changes during resistance of cowpea to Fusarium oxysporum f.sp. tracheiphilum

We evaluated a resistant cultivar(R,Fengchang No.2) and a susceptible cultivar(S,Zhijiang28-2) of cowpea(Vigna sesquipedalis) for changes in the activities of defence enzymes after inoculation of 2,4,6,8,10 d with Fusarium oxysporum f.sp. tracheiphilum.Preoxidase (POD),polyphenol oxidase(PPO),phenylalanine amino-lyase (PAL),catalase(CAT),chitinase and β-1,3-glucanase and the content of malonaldehyde(MDA) in leaves were analyzed. It was found that(1)The activities of 6 enzymes and MDA content showed no significant changes in uninoculated leaves both in resistant and susceptible cultivar.(2) After fungal inoculation,the activities of all enzymes were promoted,there had higher activities in PPO,CAT and MDA in the resistant cultivar comparing with the susceptible.(3)The activities of PPO,POD,CAT and chitinase changed earlier in R than in S after fungal inoculation,indicating the relationship to triggering resistant response to infection.