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Apple snails (Pomacea canaliculata Lamarck) belongs gastropods (Gastropoda), snails Branch (Ampullariidae). Apple snails are aquatic crops and crop damage xeric waters near a class of more serious harm snails, place an area has expanded each year, endangering increasing. I started in Fuzhou from 2008 through field investigation and laboratory testing by combining apple snails spawning habits, field eggs, egg development, egg shell height width, addicted to diet, food consumption, drought (famine) capabilities, Indoor populations wintering mortality viability and biological characteristics of the system studied; and current production were measured more commonly used five kinds of pesticides on different age snails snails virulence. The results are as follows: apple snail egg masses are mainly distributed in the vertical height from the surface of the host between 11 ~ 35cm or canal wall (accounting for 89.2%). Snails fecundity increases with rain days and rainfall decreases with temperature increases. Egg development rate and temperature is linear regression equation used Y = 0.006X-0.068 to represent; egg developmental threshold temperature and effective accumulated temperature was 14.2 ℃ and 152.16 day · degree. Hatchability and relative humidity is linear regression equation used Y = 2.24X-103.417 representation. Apple snail shell height and shell width is proportional to the growth, with an average ratio of 1.32. Lo age and shell height, shell width relationship was logistic model, the regression equation Y = 29.5203 / (1 EXP (2.5972-0.044251X)) and Y = 21.9053 / (1 EXP (2.4041-0.039919X)). 10 kinds of food palatability test determination of snails on sweet potato leaves hobby strongest, white radish leaves hobby worst. The food consumption of snails and snail logistic model showed a relationship between age, the available regression equation Y = 3876.4840 / (1 EXP (4.1493-0.055856X)) representation. Apple snails drought (famine) capability as snails increased with the increase of age. Lo Lo at age 25d 8d after treatment, the mortality rate was 83.3%; 50d snails snails in dealing 25d of age, the mortality rate of 76.7%; 75d snails snails in dealing 31d of age, the mortality rate of 83.3%; 100d snails age snails in dealing 50d, the mortality rate of 86.7%; 125d snails snails in dealing 55d of age, the mortality rate of 90%. Kept indoors, the test population growth after hatching low survival rate within the first month, only 76.8%. Month survival after feeding on some long and stable with an average of 97.575%. Laboratory simulation of the test populations overwinter survival rate was 80.2%. After wintering survival again to a steady increase in average of 94.94%. In the indoor winter trials, snails of different sizes mortality differences are significant. Shell snails 5 ~ 10cm high mortality rate was 36%, shell height 11 ~ 15cm for 16.33%, shell height 16 ~ 25cm for 9.67%. Select five kinds of agents, indoors virulence test performed on snails. The results show that the wettable powders, the snails to 45% triphenyl most sensitive acid, its 20d, 40d, 60d, 80d, 100d and 120d Lo Lo age test The LD50 values 168.6768g/hm ~ 2 , 220.9243g/hm ~ 2,288.0803 g / hm ~ 2,359.5908 g / hm ~ 2,472.6099 g / hm ~ 2 and 543.6025g/hm ~ 2. In granules, apple snails for 6% A Neville · metaldehyde strongest sensitivity for snails. Its 20d, 40d, 60d, 80d, 100d, 120d try snails snails age LD50 values 2517.9169g/hm ~ 2,1074.0023 g / hm ~ 2,843.2485 g / hm ~ 2,746.4958 g / hm ~ 2,794.8684 g / hm ~ 2 and 372.6845g/hm ~ 2.
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