| Pomacea canaliculata Lamarck(Gastropoda:Ampullariidae) was one of the most serious pests of aquicolous and terricolous crop around water area.The damage was more and more severely.The paper studied systematically in the biological characteristics of P.canaliculata by the methods of field investigation and laboratory experiment,including oviposition habit,field egg quantity,egg development,height and width of shell,food preference,appetite, drought (hunger) tolerance,indoor population livability,overwintering mortality,and so forth.The toxicity of five kinds of pesticides to P.canaliculata were tested in laboratory.The results are as follows:The results showed that about 89.2% of eggs were distributed on the host plants above the water by 11～35cm on the wall. The egg quantity of P.canaliculata was reduced with the increase of rain days and rainfall,but increased with the raising of temperature.There was a linear relationship between the developmental rate of eggs and the temperature,and the regression equation was Y=0.006X-0.068;The developmental threshold temperature of eggs was 14.2℃,and the effective accumulating temperature was 152.16 degree-days.There was also a linear relationship between the hatchability and the humidity,and the regression equation was Y=2.24X-103.417.The height and width of shell of P.canaliculata scaled up well with the ratio of 1.32±0.09.There was a logistic model between the height,width and the instar,and the regression equation was Y=29.5203/(1+EXP(2.5972-0.044251X)) and Y=21.9053/(1+EXP(2.4041-0.039919X)).The food preference experiment showed that Ipomoea batatas was the most preferential food and Raphanus sativus was on the contrary.There was a logistic model between the appetite and the instar,and the regression equation was Y=3876.4840/(1+EXP(4.1493-0.055856X))。The drought (hunger) tolerance of P.canaliculata was enhanced with the development of the instar.The mortality of 25-day P.canaliculata was 83.3% after 8-day treatment;the mortality of 50-day P.canaliculata was 76.6% after 25-day treatment;the mortality of 75-day P.canaliculata was 83.3% after 31-day treatment;the mortality of 100-day P.canaliculata was 86.7% after 50-day treatment;the mortality of 125-day P.canaliculata was 90% after 55-day treatment.The livability of P.canaliculata population in door at the first month after hatching was relatively low,about 76.8%.The livability tended to remain stable one month later about 97.575%.The simulation overwintering indoor showed that the livability during the overwintering was 80.2%.Then the livability was stable again after the overwintering,about 94.94%.The mortality was obvious different according to different instars during the simulation overwintering experiment in door.The mortality of 5～10cm-height P.canaliculata was 36%;The mortality of 11～15cm-height P.canaliculata was 16.33%;The mortality of 16～25cm-height P.canaliculata was 9.67%.The toxicity test of five kinds of pesticide on P.canaliculata was done in laboratory.The results showed that P.canaliculata was most sensitive to 45% Fentin Acetate in wettable powder, which LD50 was 168.6768g/hm~2(20-day old P.canaliculata),220.9243g/hm~2(40d),288.0803g/hm~2 (60d),359.5908g/hm~2(80d),472.6099g/hm~2(100d),543.6025g/hm~2(120d);in granules,on the other hand,P.canaliculata was most sensitive to 6% Carbaryl·Metaldehyde,which LD50 was 2517.9169g/hm~2(20d),1074.0023g/hm~2(40d),843.2485g/hm~2(60d),746.4958g/hm~2(80d), 794.8684g/hm~2(100d),372.6845g/hm~2(120d).
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