黑胫病生防菌施用后对不同抗性烟草品种酶活性和 MDA 含量的影响

为了探究生防菌对烟草抗病性的影响，2012年，以对黑胫病抗性不同的高抗品种（云烟87）、中抗品种（ K326）和感病品种（红花大金元）等3种烟草品种70天苗龄的实生苗为实验材料，在烟苗茎秆接种黑胫病原后施用该生防菌，于不同接种时期（0天、15天、30天、45天、60天、75天）测定叶片中苯丙氨酸解氨酶（PAL）、多酚氧化酶（PPO）、过氧化物酶（POD）的活性及丙二醛（MDA）含量。结果表明，（1）高抗品种、中抗品种和感病品种的PAL、 PPO及POD活性水平皆明显高于各自的对照，且前期增加速度表现为高抗品种＞中抗品种＞感病品种，后期PPO活性减小情况也符合以上规律。（2）高抗品种、中抗品种和感病品种的MDA的含量增加速度明显低于各自的对照，前期MDA含量增加的速度和后期降低的速度均是感病品种＞中抗品种＞高抗品种。可见，施用该生防菌可通过调节抗性酶活性和MDA含量提高烟株对烟草黑胫病的抗病性。

Variation of Enzymatic Activity and MDA Contents in Tobacco Cultivars with Different Resistance Response to Black Shank Bio-control Bacteria Inoculation

For understanding the effect of a bio-bacterial strain on tobacco disease resistance , three 70-day-tobac-co cultivars with different resistance to black shank were used as materials in 2012.Phenylalanine ammonia lyase （ PAL） , polyphenol oxidase （ PPO） , peroxidase （ POD） and content of malondialdehyde （ MDA） in different pe-riod （0 d, 15 d, 30 d, 45 d, 60 d and 75 d） after infected with pathogen of tobacco black shank and applica-tion of bio-bacterial strain The results showed that： 1） PAL, PPO and POD of high resistant variety , resistant va-riety and susceptible variety were much higher than those of their control , and the increasing speed at early stage showed as high resistant variety 〉resistant variety〉susceptible variety , and decreased of PPO activity later was al-so comply with the above rules .2） The increase speed of MDA content of high resistant variety , resistant variety and susceptible variety was much lower than those of their control , and the increasing speed at early stage and de-creasing speed at later stage of MDA content showed as susceptible variety 〉resistant variety 〉high resistant varie-ty.In this sense , by adusting resistant enzyme activity and MDA content , tobacco black shank disease resistance could be improved .