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The apple snail (Pomacea canaliculata) was studied in this article, including high temperature, Low temperature, drought, and starvation stress conditions on apple snails survival, growth, development and reproduction, the reaction by observing its behavior to determine its survival rate, growth rate and an average maximum food rate, the content of the three physiological indicators, clear apple snails on changes in the environment and its physiological indexes of correlation. The results was advantage to developing further disaster risk assessment and analysis of its spreading to provide a basis materials in the future, and thus provide the basis for the development of paddy apple snails prevention and control strategies and select effective control measures. The results of the study are as follows:1. The impact of high temperature force on apple snails. This study shows the effect of high (37,39, and41℃) and low (12,15and18℃) temperatures for30days on both mature and adult stages of Pomacea canaliculata for the survival, development and feeding rate under classical laboratory conditions. The rise in temperature is inversely propotional to the measuring prameters with maximum survival rate of84.44%. The survival rate and foraging behaviour of both mature and adult stages of P. canaliculata under the persistant low temperatures is reduced with no ovipositon at all while adult oviposition, intermittent temperature has no significant effect.2. The impact of Low temperature force on apple snails The survival rate of young and mature stages under low temperatures for30days is reduced while no effect on adult stage. The developmental rate (the weight) of young and adult is decreased at the persistent12and15℃low temperature treatements. There is slight decrease in the average maximum feeding rate for young, mature and adult stages. As compared to non-significant persistent treatment for survival rate, the developmental rate (the weight) of mature and adult P. canaliculata decreased under intimettent low temperature treatment (12℃,15℃). To the conclusion, the decrease in weight (4.95and7.89%) for mature while for adult weight (-22.83and-1.41%) decreased at12and15℃, respectively after30days treatment.3. The impact of starvation force on apple snails Under the condition of water for30d. as a result, survival rate of the youth, mature stage and adult apple snail were0,11%,13%, respectively. Meanwhile, the weight had decreased. With the control of persistent starvation which had reached sexual maturity did not produce offspring.Under the persistent hungry processing, the content of crude protein, crude fat and crude sugar in adult apple snail were lower than the normal ones. However, this phenomenon differs from the treatment of periodic starvation, because the content of crude protein and crude sugar were more than the control, but opposite to that of the crude fat. In spite of, the content of crude protein contained in mature stage apple snails was the same as that of the control, the content of fat and crude sugar kept increasing with the extension of starvation time.4. The impact of drought force on apple snails In order to withstand the adverse environment, apple snail turned into dormancy in the treatment of drought stress, and broke automatically when the drought conditions disappeared. The drought stress played a role on the behavioral reaction of the apple snails, but did not effect its survival in a month.
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