南方根结线虫侵染对2个不同抗性番茄砧木幼苗苯丙烷类代谢的影响

Effects of Infection with Meloidogyne incognita on Phenylpropanes Metabolism in Two Different Resistant Tomato Rootstock Seedlings

摘要:

为明确不同抗性番茄(Lycopersicon esculentum)砧木幼苗苯丙烷类代谢与抗南方根结线虫(Meloidogyne incognita)的关系,以高感砧木‘Ls-89’和高抗砧木‘坂砧2号’为试材,采用盆栽人工接种二龄幼虫的方法,研究番茄砧木幼苗苯丙烷类代谢的变化。结果表明,未接种根结线虫时,‘坂砧2号’的根系PAL活性与‘Ls-89’无显著差异,而根系PPO活性及叶片PAL、PPO活性和总酚、类黄酮、木质素含量却显著高于‘Ls-89’。接种根结线虫后,两砧木根系与叶片的PAL、PPO活性与总酚、类黄酮含量均呈周期性升高,木质素含量也逐渐升高,但‘坂砧2号’的升幅均显著高于‘Ls-89’。在一个侵染周期内,‘坂砧2号’根系PAL、PPO活性与总酚、类黄酮含量的峰值分别比‘Ls-89’高28.45%、71.47%、54.24%、91.71%,而叶片的分别高47.29%、64.00%、23.33%、52.61%。这说明南方根结线虫侵染使砧木幼苗苯丙烷类代谢活性显著增强,且‘坂砧2号’显著高于‘Ls-89’,表明番茄砧木幼苗苯丙烷类代谢与抗南方根结线虫水平密切相关。

Abstract:

To understand the relationship between phenylpropanes metabolism in tomato rootstock seedlings and their resistance to Meloidogyne incognita, highly susceptible rootstock ‘Ls-89’ and highly resistant rootstock ‘Banzhen No. 2’ were selected as materials, planted in pots and inoculated with second instar larvae. The effect of M. incognita infection on the phenylpropanes metabolism in roots and leaves of tomato rootstock seedlings was studied. The results showed that the phenylalanine ammonia lyase (PAL) activity in ‘Banzhen No. 2’ and ‘Ls-89’ roots had not significant difference without inoculation, but polyphenol oxidase (PPO) activities in ‘Banzhen No. 2’ roots, PAL and PPO activities, total phenolic, flavonoid and lignin contents in ‘Banzhen No. 2’ leaves were significantly greater than those in ‘Ls-89’. After inoculated by M. incognita, PAL and PPO activities, total phenolic and flavonoid contents in roots and leaves of two rootstocks increased cyclically, while the lignin contents gradually increased, and their increases in ‘Banzhen No. 2’ were significantly greater than those in ‘Ls-89’. In an infection cycle, the peak values of PAL and PPO activities, total phenolic and flavonoid contents in ‘Banzhen No. 2’ roots were greater than those in ‘Ls-89’ for 28.45%, 71.47%, 54.24%, 91.71%, respectively, while those in ‘Banzhen No. 2’ leaves were higher than those in ‘Ls-89’ for 47.29%, 64.00%, 23.33%, 52.61%, respectively. Therefore, phenylpropanes metabolism activities were significantly enhanced infected by M. incognita, and those in ‘Banzhen No. 2’ were significantly higher than those in ‘Ls-89’, So, it was suggested that there were close relation between the phenylpropanes metabolism in tomato rootstock seedlings and resistance to M. incognita.