叶损伤对兴安落叶松防御酶活性的系统诱导  

Systemic Induction of Defensive Enzymes in Needles of Larix gmelinii Seedlings in Wounded Conditions

作　　者：王琪[1] 严善春[1] 金虎[1] 王艳军 

机构地区：[1]林木遗传育种国家重点实验室(东北林业大学),哈尔滨150040 [2]内蒙古克什克腾旗林业局森防站

出　　处：《东北林业大学学报》2012年第9期77-80,共4页Journal of Northeast Forestry University

基　　金：国家公益性行业科研专项(200904021);国家自然科学基金项目(30371163);黑龙江省重点基金项目(ZJN0603-01)

摘　　要：为了研究剪叶及昆虫取食诱导与兴安落叶松(Larix gmelinii)针叶内苯丙氨酸解氨酶和多酚氧化酶活性变化的关系,以剪叶及落叶松毛虫(Dendrolimua superans)取食处理兴安落叶松幼苗,用紫外分光光度法测定针叶内苯丙氨酸解氨酶和多酚氧化酶活性的变化趋势。结果表明:剪叶或松毛虫取食均能强烈诱导苯丙氨酸解氨酶和多酚氧化酶活性,4枝50%为最适的损伤程度。多酚氧化酶活性在达到最大值后迅速下降,苯丙氨酸解氨酶活性的持续时间较长。当损伤程度为4枝50%时,松毛虫取食与剪叶处理诱导的苯丙氨酸解氨酶的活性无显著差异,取食诱导的多酚氧化酶的活性显著高于剪叶诱导,但2种处理方法诱导的防御酶活性变化趋势相同,均在同一时间表现出最高的酶活性。因此推测,松毛虫取食与机械损伤可能诱导相同的防御系统,可以考虑通过机械损伤拟合昆虫取食,从而达到较理想的诱导防治效果。An experiment was conducted to study the activity changes in polyphenol oxidase （PPO） and phenylalanine ammonia- lyase （PAL） in Larix gmelinii seedlings after damaged by needle cutting or feeding by Dendrolimus superans （ Lepidoptera： Lasiocampidae） larvae. The activities of these enzymes in needles of L. gmelinii seedlings before and after damage were compared using UV-spectrometry bioassays. Results showed that the activities PPO and PAL in needles of L gmelinii seedlings significantly increased after both needle cutting and feeding by D. superarts larvae, and cutting four branches with 50% of leaves was the most appropriate damage degree. The activity of PPO rapidly declined after reaching its peak values, while elevated PAL activity tended to remain longer. The activity of PAL caused by D. superans was not significantly diffe- rent from that by cutting four branches with 50% of leaves. In contrast, D. superans caused a more intensive increase in PPO activity than needle cutting, but the tendency of changes in activities of defensive enzymes induced by D. superans were similar to those by cutting needles, and the maximum activities of defense enzymes induced by the two treatments ap- peared after similar time lags following cutting or feeding. The results clearly demonstrated that caterpillar feeding and mechanical wounding may resulted in the same inducible defense system, but response intensities of plants were different in these two treatments. Therefore, it implies that the effective methods of pest control could be obtained using mechanical wound intentionally to mimic the effects of herbivore attack.

关 键 词：兴安落叶松 落叶松毛虫 苯丙氨酸解氨酶 多酚氧化酶 剪叶损伤 昆虫取食 

分 类 号：S433.1[农业科学—农业昆虫与害虫防治] S791.222[农业科学—植物保护]