玉米灰斑病抗性反应中酚类物质代谢作用的研究

 研究了玉米灰斑病菌(Cercospora zeae-maydis)侵染前后的4个玉米品种苯丙氨酸解氨酶、过氧化物酶、多酚氧化酶及木质素含量的变化。3种酶比活性在病菌侵染后都发生明显的先增后降的变化,而抗病品种的变化要明显大于感病品种的变化,尤其是苯丙氨酸解氨酶最大增加活性与品种抗病性呈现极显著的相关性。4个品种的木质素含量在病菌侵染的第9 d时增加到最大值,以后略下降,而且抗病品种的木质素含量峰值高于感病品种的峰值。

The function of phenolic metabolism in resistant mechanism of gray leaf spot of corn

The activities of three enzymes related to phenolic metabolism and lignin biosynthesis were studied in four corn cultivars with different level of resistance to the pathogen of gray leaf spot (Cercospora zeae maydis Tehon & Daniels). The phenylalanine ammonialyase (PAL),peroxidase (POD) and polyphenoloxidase (PPO) showed the induced activity peaks following the inoculation. The increasing of these enzymes was more significant in resistant cultivars than in susceptible cultivars. Especially, the increase of PAL activity in different cultivars was positively related with their level of resistance to the pathogen. Lignin, one product from phenolic metabolism pathway, increased in four cultivars and had its maximum 9 days after inoculation. The resistance cultivars showed higher level of lignin content than that in susceptible cultivars.