2种植物生长调节剂诱导烟草抗链格孢菌研究

Induction of Tobacco Resistance to Alternaria alternata by Two Plant Growth Regulators

以链格孢菌Alternaria alternata和烟草Nicotiana tabacum品种云烟87为试材,研究不同浓度茉莉酸甲酯(MeJA)和水杨酸(SA)处理下,链格孢菌菌丝生长情况以及成熟期烟叶防御酶活性与多酚含量变化,探讨植物生长调节剂对烟草抗链格孢菌的影响。结果表明,1 mmol·L^(-1)MeJA对链格孢菌的抑制效果最好,抑菌率高达59%以上,其次是3.5 mmol·L^(-1)SA;MeJA和SA对链格孢菌的抑制效果随药剂浓度升高而增强;0.1 mmol·L^(-1)MeJA和2.5 mmol·L^(-1)SA能诱导烟草叶片SOD、POD、CAT等防御酶活性,并能降低H2O2活性氧含量,尤其以MeJA诱导效果较好。2种植物生长调节剂处理并接种链格孢菌能诱导提高烟叶多酚代谢相关酶PPO及PAL活性,但对烟草多酚类物质影响较小;成熟烟叶中含量较高的前3种多酚物质是绿原酸、芸香苷、隐绿原酸。

In order to explore the effects of plant growth regulators on the metabolism of antioxidant enzymes and polyphenols of tobacco,the mycelia growth of Alternaria alternate,under treatment with different concentrations of methyl jasmonate(MeJA)and salicylic acid(SA),the defense enzyme activities and polyphenol contents in tobacco mature leaves inoculated with and uninoculated with A.alternata were measured.The results showed that 1 mmol·L^(-1) MeJA had the best inhibitory effect on A.alternata,and the inhibitory rate was more than 59%,followed by 3.5 mmol·L^(-1) SA.The inhibitory effect of MeJA and SA on A.alternata was enhanced with the increase of growth regulator concentration.The treatment with 0.1 mmol·L^(-1) MeJA and 2.5 mmol·L^(-1) SA could induce SOD,POD and CAT defense enzymes activities in tobacco,and reduce H2O2 reactive oxygen content,while MeJA had better induction effect.Treatment with the two plant growth regulators and inoculating with the A.alternata could induce and improve the activities of PPO and PAL in tobacco leaves,which were related to polyphenol metabolism,but had little effect on tobacco polyphenols.The top three polyphenols with high content in mature tobacco leaves were chlorogenic acid,rutin and cryptochlorogenic acid.