The Adaptability Of Ophraella Communa To High Temperature Change

Ophraella communa is a special natural enemy of the invasive weed----ragweed,which shows effective control effect on ragweed.In this study,we simulated three summer temperature fluctuation modes.The first mode simulates the regular changing diurnal temperature(32 ± 4?)of summer,the second mode is rising the average day temperatures by 2? and the third one is rising the highest temperature by 2? with constant temperature 28? served as control.We further investigated the response of O.communa's Hsp70 to temperature stress from the perspective of molecular biology.The purpose of this study is to reveal the adaptability of O.communa to summer temperature changes,and provide basic data for predicting the development trend of O.communa under climate changes.This study used the methods of biology,physiology and biochemistry,and molecular biology to study:(1)The effects of different day and night temperature fluctuation on the development and reproduction of O.communa.(2)The effects of different day and night temperature fluctuation on the contents of total sugar,glycogen,glycerol,protein,MDA and activities of SOD,CAT and GST in O.communa.(3)The expression of hsp70 was induced at high temperature after cloning of hsp70.Research results:(1)The different day and night temperature fluctuation in summer shortened the developmental duration of O.communa,reduced the survival rate,and the number of eggs-laying.Increasing the average and highest summer temperature by 2?reduced the hatching rate of egg and the survival rate of larvae significantly.(2)The different day and night temperature fluctuation in summer all increased SOD activity,CAT activity,GST activity,glycerol content,and protein content in O.communa.(3)Successful cloning of hsp70.At different heat shock temperatures,the hsp70 expression was the highest at 36?.This study shows that the different day and night temperature modes in summer changes the biological characteristics of O.communa,while O.communa(it)responded positively to temperature changes of summer by changing the content of nutrients and adjusting the activity of antioxidant enzymes in its body,hsp70 played an important role in the heat resistance ability of O.communa.