关键词: 磷素形态, 温度, 石灰性潮土, 小麦根际

Abstract: To clarify the effects of feedingmodes of different insects on systematic defenses in kidney bean plant, we examined the impacts of damages by tobacco cutworm Spodoptera litura(chewing), spider mite Tetranychus urticae (piercingsucking), and western flower thrips Frankliniella occidentalis (raspingsucking) after 6, 24, 48, and 96 h of feeding middle leaves on activities of polyphenols oxidase (PPO) and phenylalnine ammonialyase (PAL) in the damaged middle leaves and undamaged upper and lower leaves of kidney bean plant. The results showed that PAL and PPO activities were significantly influenced by treatment types, periods of time and leaf position (P<0.01), with significant interactions among the three factors. The activities of PPO in middle leaves increased significantly at 6 h in all different treatments (P<0.05), and changed in different patterns with time extension. The PAL activity in middle leaves was not significantly activated until 48 h after mechanical damage (CK). The activities of PAL in middle leave fed by S. litura, T. urticae and F. occidentalis increased obviously at 6, 6 and 24 h, and reached the maximum, being 2.66, 1.75 and 2.79 times of the control, respectively. The responses of the PAL and PPO in undamaged upper and lower leaves by herbivore feeding were faster than that by mechanical damage. T. urticae feeding caused the fastest changes of PAL activity. The activities of PAL in the upper and lower leaves by T. urticaefeeding reached the maximum at 6 h, which were 2.72 and 5.07 times of the control, respectively. Our results indicated that herbivore feeding could induce the systematic defenses of kidney bean plant, with the effects of temporal and spatial defenses  related to the types of pests.

Key words: phosphorus form, temperature, calcareous fluvo-aquic soil, wheat rhizosphere