花绒寄甲对高温胁迫的适应能力及生理响应

Adaptation and Physiological Response of Dastarcus helophoroides(Fairmaire)to High Temperature Stress

商品化天敌昆虫在我国不同区域释放可能受到极端温度的影响和制约。花绒寄甲Dastarcus helophoroides(Fairmaire)是松墨天牛Monochamus alternatus Hope等蛀干害虫的重要天敌之一,具有良好的应用前景,但其在我国南方应用时控害效果常不稳定。以商品化花绒寄甲成虫为研究对象,并以常温25℃为对照,研究不同高温胁迫条件(33℃、36℃、39℃、42℃和45℃)对成虫的寿命、生殖、体内营养物质及抗氧化物活性的影响,旨在综合评价花绒寄甲成虫对高温胁迫的适应能力,为探讨其在我国南方松林中最佳释放时机、控害效果评价以及种群稳定性等方面提供科学依据。试验结果表明:高温胁迫(33℃~45℃)对花绒寄甲的成虫寿命具有显著影响,且随温度升高而显著缩短,据此可将高温区划分为致死高温区(42℃~45℃)、亚致死高温区(39℃~42℃)和高适温区(33℃~39℃),其中花绒寄甲成虫在致死高温区内无法产卵,且卵块不能孵化;表明高温胁迫诱导花绒寄甲成虫产生强烈的抗逆代谢,消耗了大量营养物质,显著改变花绒寄甲成虫体内总糖、海藻糖和甘油三酯的含量;与此同时诱导花绒寄甲SOD、CAT活性的显著升高,POD活性的显著降低,与清除自由基有关。花绒寄甲成虫商品化种群耐受高温胁迫能力较弱,建议其在选择林间释放时间时,规避高温的潜在影响。应采用高适温区(33℃~39℃)进行驯化,以增强其成虫的耐高温及控害能力。

The release of commercial natural enemy insects in different regions of China may be affected and restricted by extreme temperature.Dastarcus helophoroides(Fairmaire)is one of the important natural enemies of stem borers,such as Monochamus alternatus Hope.It has a good application prospect,but its population density is low in southern China,and its control effect is limited.In this study,the commercial adult of the D.helophoroides was taken as the research object,and the normal temperature of 25℃was taken as the control.The effects of different high temperature stress conditions(33℃,36℃,39℃,42℃and 45℃)on the longevity,reproduction nutrients and antioxidant activities of commercial adults of D.helophoroides were studied in order to comprehensively evaluate the adaptability of D.helophoroides to high temperature stress.To provide a scientific basis for the study of the optimal release time,the evaluation of control effect and the stability of the population of D.helophoroides in Pine forest in southern China.The results showed that high temperature stress(33℃-45℃)had a significant effect on the longevity of the adults,and it shortened significantly with the increase of temperature.The high temperature area can be divided into lethal high temperature area(42℃-45℃),sub lethal high temperature area(39℃-42℃)and high temperature area(33℃-39℃).The results showed that high temperature stress induced strong stress resistance metabolism,consumed a lot of nutrients,and significantly changed the contents of total sugar,trehalose and triglyceride.At the same time,the activities of SOD and CAT increased significantly and the activity of POD decreased significantly,which was related to the scavenging of free radicals.It is suggested that the release time should be chosen to avoid the potential effects of high temperature.In order to enhance the ability of high temperature tolerance and pest control,the high suitable temperature zone(33℃-39℃)should be used for domestication.