胚轴切断法诱导棉花抗棉铃虫及其生化机制研究

ON THE BIOCHEMICAL MECHANISM OF INDUCED RESISTANCE OF COTTON TO COTTON BOLL WORM BY CUTTING OFF YOUNG SEEDLING AT PLUMULAR AXIS

诱导抗虫棉株对棉铃虫营养代谢功能的影响表明,胚轴切断法结合假单孢杆菌(Pseudomonas gladioli D-2251)诱导处理的棉株可使棉铃虫相对生长率(RGR)、相对取食量(RCR)和近似消化率(AD)明显降低,分别降低22.95％、26.12％和27.23％,仅用胚轴切断法处理的棉株可使RGR、RCR和AD分别降低17.25％、21.44％和4.09％。对诱导处理棉株体内植物多元酚和抗虫萜烯类的测定结果表明,经过胚轴切断法后,菌处理和无菌处理的棉株体内植物多元酚的增幅分别为30.78％～289.99％和3.88％～139.69％,其增幅后期比前期低,在6叶期最低。菌诱导棉株和无菌诱导棉株体内抗虫萜烯类含量增幅分别为2.60％～36.22％和1.32％～26.16％。

As the cotton plants has been cut off at plumular axis in 2 - 3 leaves stage and treated with the somatotropin ABT to promote the root regeneration, the relative growth rate (RGR), relative consumption rate (RCR) and approximate digestibility (AD) of cotton bollworm(CBW) Helicoverpa armigera (Hubner) larvae fed on these young cotton plants , with and without inoculation of strain D-2251 of Pseudomonas gladioli, were compared with those on the check plants without treatments. The contents of polyphenols and terpenoids in treated cotton plants increased significantly, and the increase rates of polyphenolic contents in treated plants with and without the bacterium inoculation, in contrast to the check, ranged from 30. 78%- 289. 99% and 3. 88% -139. 69%. Then the increase range of polyphenols reduced later ,to the lowest in six leaves stage. The increase rates of terpenoid contents in treated cotton plants with and without the bacterium inoculation ranged from 2. 60%- 36. 22% and 1. 32% -26. 16%, respectively. The results mentioned above have showed certain contributing factors in association with the induced resistance occurred in treated cotton plants.