【摘要】 用来自赤星病菌弱毒株的糖蛋白激发子处理烟草 ,能明显抑制烟草体内过氧化氢酶 (CAT)的活性 ,增加组织中H2 O2 的含量。诱导后 1dCAT活性就已开始下降 ,至第 6天下降到最低 ,以后又逐渐恢复。而H2 O2 含量的变化趋势与CAT活性的变化相反 ,随CAT活性的降低 ,组织中H2 O2 含量逐渐增加 ,在诱导后第 10天达到最大值。激发子处理烟草还可以诱导碱性PR蛋白基因PR 1b的表达 ;同时 ,烟草对赤星病强毒株的抗性逐渐增强 ,以诱导后第 10天接种抗性最强 ,且这种抗性是系统性的。水杨酸 (SA)处理后CAT及H2 O2 的变化与上述趋势类似。更多还原

【Abstract】 Tobacco plants treated with a glycoprotein elicitor from the hypovirulent strain TBA 16 of Alternaria alternata, the pathogen that causes brown spot in tobacco,displayed a decreased catalase (CAT) activity and an increased hydrogen peroxide (H 2O 2) content,similarly as did plants treated with salicylic acid(a positive control), compared with the negative control (treatment with sterilized water).CAT activity began to decline one day and got to the lowest level at the sixth day,while H 2O 2 content elevated continuously and reached to the highest level ten days after induction.Application of the elicitor to tobacco induced expression of PR 1b ,a gene encoding basic pathogenesis related protein 1b.Treatment of tobacco with the elicitor induced systemic resistance to the virulent strain TBA28 of the pathogen.更多还原