黄瓜及其近缘种对南方根结线虫的抗性及酶响应变化的研究

 选取6份黄瓜品种和2份近缘种(非洲角和酸黄瓜) 进行了南方根结线虫病抗性鉴定, 2份 近缘野生种高抗南方根结线虫病, 6份黄瓜品种为感病类型。接种前后根系酶活性与病情指数相关性分析表明, 超氧化物歧化酶( SOD) 、过氧化物酶( POD) 、苯丙氨酸解氨酶( PAL) 活性变化与其病情指数分别呈显著正相关( r = 0.8278*) 、极显著负相关( r = - 0.9679** ) 和显著负相关( r = - 0.8499*) 。POD同工酶电泳分析表明, 抗病材料酸黄瓜较未接种对照增加了3 条酶带(相对迁移率Rf = 0.126, 0.188,0.944) , 而感病材料北京截头只增加了1条弱带(Rf = 0.396) 。SOD、POD及PAL活性水平可作为甜瓜属作物抗根结线虫病鉴定的生化指标及常规抗性鉴定方法的补充。

Cucumber and Its Related Species for Resistance to the Sourthern Root-knot Nematode Meloidogyne incognita and Respond to Changes of Enzyme

The eight Cucumis germplasms were selected for evaluation of their resistance to the root-knot nematodes Meloidogyne incognita.The results showed that the two Cucumis wild relatives were highly resistant to Meloidogyne incognita,and the six varieties of cucumber were all susceptible.The correlation analysis between the rates of changes of superoxide dismutase(SOD),peroxidase(POD),phenylalanine ammonialyase(PAL)in roots before and after inoculation and disease index for Cucumis species tested was performed.The results showed that there was a significant positive correlation of SOD(r=0.8278*),highly significant negative correlation of POD(r=0.9679**)and significant negative correlation of PAL(r=0.8499*) associated with the disease index,respectively.POD isoenzyme electrophoresis analysis showed that there were three more enzyme bands(Rf=0.126,0.188,0.944)in the resistant genotype'C.hystrix',but only one weak band(Rf=0.396)in the susceptible genotype'Beijing Jietou'when compared to noninoculated control.The level of SOD,POD and PAL activities can be used as the biochemical markers and the supplement for the conventional method of evaluation for resistance to the root-knot nematodes in Cucumis species.