Effects Of Cultural Temperature,Humidity And Evaporation On The Activities Of AchE And CarE Of Piutella Xylostella Larvae

The indoor experiments were conducted to test the activityvariations of acetylcholinesterase(AchE) and carboxyesterase(CarE) in the 4th instar larvae of Plutella xylostella due to the constant cultural temperature,humidity (presented as the variation between the dry-bulb and the wet-bulb temperatures) and evaporation. The results are summarized as follows:(1) Under the conditions of 25±1℃and 75%RH, the LC-P equation of the relationship between Avermectin and P. xylostella was estimated as: Y =-1．61X + 10．882 (r=0．9920, d. f. =3, P<0．01) .(2) The linear equation of the relationship between the activities of AchE(Y) and cultural temperatures(X) was estimated as: Y =-0．0002X + 0．0068 (r=0．9601,d.f=3,P<0．01) , and that as Y =-0．0078X + 0．3127 (r=0．9418, d. f=3, P<0．05) for CarE.(3) The equation for the relationship between the activities of AchE(Y) and humidity(X) was estimated as: Y =-0．0003X~2 + 0．0023X-0．0004(d. f. =3, P<0．05) , and that as Y =-0．0168X~2 + 0．1148X-0．0036 (d. f. =3, P<0．05) for CarE.(4) Under the outdoor conditions in Dec. 2006, the activities of AchE and CarE significantly varied by the evaporation variations.