Studies On The Cold Tolerance Of Brontispa Longissima(Gestro)

Brontispa longissima (Gestro) is one kind of quarantine insect pests, major hazards palm plants. It already caused significant harm on coconut, betel nut industry in Hainan and Guangdong province. Brontispa longissima(Gestro) distributed in low latitudes so far, such as the whole Hainan island and parts of Guangxi, Yunnan, Guangdong province. In order to determine whether the pest could continue to spread, meanwhile, fill the gaps in Brontispa longissima(Gestro) cold tolerance research. By studying the short-term low temperature on the the Brontispa longissima(Gestro) adults influence the physiological state to determine whether they have a certain pest tolerance to cold, and research the system of cold hardiness substance. The research revealed the adults of Brontispa longissima could sharply accumulate trehalose, glycogen, glycerol, fat, protein, and increase the activity of SOD、POD、CAT to respond to the low temperature environment.1、-20℃lethal time of Brontispa longissima(Gestro)Under the-20℃cold stress10、20、30and32minutes the mortality of Brontispa longissima(Gestro) which under4℃cold acclimation was20%、34%、47%and57%, obviously lower than the control groups27%、50%、93%and100%. Experiment found the treatment group need at least40minutes to kill all the Brontispa longissima(Gestro) adults under the-20℃cold stress. But the control group only needs32minutes. The differences between the two groups of lethal time were striking.2, Content of free water in adult of Brontispa longissima(Gestro)The content of free water was67.10%in control group adults. However it is45.11%in treatment group. The result revealed that Brontispa longissima sharply decrease the content of free water to respond to the low temperature environment.3, Content of saccharides(total carbonhydrate, trehalose, glycogen) in adult of Brontispa longissima(Gestro)Experiment found in treatment groups the total carbonhydrate slightly decreased from19.82(μg/mg) to18.00(μg/mg), yet the content of the trehalose, glycogen showed large accumulation compared to the control groups. Trehalose increased from3.22(μg/mg) to5.88(μg/mg); glycogen increased from1.12(μg/mg) to4.46(μg/mg). So the adults of Brontispa longissima could accumulate trehalose and glycogen to respond to the low temperature environment. 4、Content of glycerol in adult of Brontispa longissima(Gestro)Experiment found in treatment group the content of glycerol sharply increased from11.45(μg/mg) to15.10(μg/mg) compared to the control group. It showed that the adults of Brontispa longissima could accumulate glycerol to respond to the low temperature environment.5、Content of fat in adult of Brontispa longissima(Gestro)Experiment found in treatment group the content of fat sharply increased from6.43%to8.14%compared to the control group. It showed that the adults of Brontispa longissima could accumulate fat to respond to the low temperature environment.6、Content of protein in adult of Brontispa longissima(Gestro)Experiment found in treatment group the content of protein sharply increased from1.23(μg/mg) to1.32(μg/mg) compared to the control group. It showed that the adults of Brontispa longissima could accumulate protein to respond to the low temperature environment.7、The activity of Superoxide Dismutase(SOD)%Peroxidase(POD)、Catalase(CAT) in adult of Brontispa longissima(Gestro)The activity of SOD in treatment group slightly increased from6.65(U/mg) to7.56(U/mg). The activity of POD in treatment group significantly increased from1.36(U/mg) to1.95(U/mg)(p<0.01). The activity of CAT in treatment group slightly increased from1.49(U/g) to1.98(U/g). It showed that the adults of Brontispa longissima could increase the activity of SOD%POD、CAT to response to the low temperature environment.