4种防御酶在木薯-细菌性枯萎病菌反应中的活性变化

不同木薯种质对细菌性枯萎病的抗性是不同的。本研究选择2个抗病和2个感病木薯种质,接种病原菌后评价了过氧化物酶(POD)、多酚氧化酶(PPO)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)的活性变化。结果表明:病菌侵染后POD活性呈上升趋势,接种后6 d达最高峰,随后呈下降趋势,且抗病种质显著高于感病种质;接种时,抗病种质PPO活性显著增高,随后下降,且抗性种质高于感病种质;CAT活性变化与抗病反应之间无相关性;抗感种质的SOD活性在病菌侵染后均表现出类似的下降趋势。由此表明,POD和抗病反应具有较强的相关性。

Activity Changes of Four Defensive Enzymes in Cassava Resistant Reaction to Xanthamonas axonopodis pv.manihotis

There is different resistance reaction in cassava varieties against Xanthamonas axonopodis pv.manihotis.Activity changes of peroxidase(POD),polyphenol oxidase(PPO),superoxide dismutase(SOD) and catalase(CAT) in two resistant and two susceptible germplasms with different reaction were studied.The activity of POD was increasing and decreasing followed,the highest value was appeared at the sixth day,and the resistant germplasms were notably higher than susceptible germplasms.The PPO activity was obviously enhanced at the inoculative time and subsequently weakening,resistant germplasms were higher than susceptible germplasms.The CAT activity changes weren’t related with resistant reaction.The similar downtrend was emerged on the SOD activity of all the germplasms.These results showed a strong correlation between resistance reaction and POD.