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Apple snails (Pomacea canaliculata), originating in South America, the Amazon River basin, is a tropical and subtropical species, is a large freshwater edible snails. Guangdong aquaculture introduced from Taiwan in 1981, and soon extended to all parts of the country, and southern China crops biological predators on a big threat to rice production. South of latitude 30 ° the provinces have apple snails hazards reported. The extent of the harm is positively correlated with temperature and negatively correlated with latitude into their breeding generations into a positive correlation. Apple snails or the zoonotic Guangzhou Angiostrongylus spread in the most important one of the intermediate host, if eaten raw or uncooked apple snails snail meat, can easily cause the foodborne Guangzhou angiostrongyliasis, causing the body increased eosinophil meningitis. The apple snails caused great negative impact on the ecological environment and economic activity. In this study, Suzhou, Jiangsu (120 ° 62'E, 31 ° 32'N), Zhangzhou, Fujian Province (117 ° 35'E, 24 ° 52'N) and Zhuhai, Guangdong (113 ° 52'E, 22 ° 3'N) snails materials, different geographical groups, different breeding generations, breeding base and genetic variability of different shell color apple snails, apple snails fecundity, mating selective, genetic diversity and genetic structure variation characteristics for the control of apple snails on the the rice seedlings hazards and to provide a scientific basis to prevent its spread. The main results and conclusions are as follows: 1, the fecundity of different geographical populations of apple snails comparison. With single mating method to the average individual fecundity of the apple snails, the the individual spawning number of blocks and individual weight relative fecundity of the female screw index analysis of different geographical populations of different shell color apple snails fecundity. The results showed that the variation pond in fecundity. In individual fecundity, Lo, Fujian and Jiangsu snails were significantly different (P lt; 0.05); individual weight relative fecundity of the female screw, Guangdong Lo Lo, Fujian, Guangdong Lo Jiangsu Lo significant difference (P lt; 0.05); different regions, different mating the number of individual spawning block difference is not significant (P gt; 0.05); different shell color apple snails fecundity was not significantly different (P GT; 0.05); different the individual mating male and female size of its mating production positively correlated with the amount of eggs and the female screw body size into body size has nothing to do with the male screw; the female snails individual the greater the amount of spawning more, but the smaller the relative fecundity; the female screw fecundity and the number of egg masses was positively correlated. The apple snails fecundity and environmental conditions, type of food, temperature and other factors are closely related. 2 different geographical populations of apple snails mating selective. In vitro labeling method of selective mating of the three geographical populations of apple snails were observed, the results showed that: Guangdong apple snails tend to mate with each other within the groups, Fujian Lo Jiangsu snails tend to hybridize to each other in different geographical populations; mate choice in apple snails test found that apple snails mating the mixed fixed spouses, the mating between the different shell color apple snails was significantly higher than the same shell color apple snails mating (P lt; 0.05); female snails mating between individuals is greater than the male screw mating form the vast majority of (P lt; 0.05). 3, the inheritance of different shell color apple snails. Application of a single pair of mating method of different shell color apple snails Jiangsu cultured population genetic law,: apple snails yellow and black shell color is a pair of opposing traits controlled by nuclear genes unrelated to sex, genetic law according to Meng Del single factor segregation law, the wild population survey found that apple snails shell color differences naturally exist, but the proportion of different shell color in different regions was different, mainly in Guangdong Lo Black, screw yellow in Yunnan, Fujian the snails and Jiangsu screw in Wong Lo more than black snails. 4, AFLP analysis of genetic diversity of different geographical populations of apple snails. Screened from primers (E32M54, E42M61, E42M54, E45M62, E32M61, E32M62, E32M59, E39M54) apple snails of the three groups in Fujian, Jiangsu and Guangdong AFLP amplification, a total of 382 distinct sites, polymorphism the locus ratio was 96.60%, and the different primer combinations generated amplified loci for 35-61, and an average of 47.75. Fujian, Jiangsu and Guangdong, three groups of polymorphic loci ratio were 85.08%, 84.82% and 79.06%; Nei's gene diversity index 0.2860,0.2819 and 0.2710, respectively; Shannon's diversity index were 0.4308,0.4259 and 0.4079 ; rich in genetic diversity, Fujian Lo genetic diversity highest Guangdong Lo minimum. Genetic distance among populations of 0.0845-0.1017 the screw, Fujian and Guangdong Lo genetic distance (0.0845), of Guangdong Lo Jiangsu Lo genetic distance (0.1017). Trait loci found three groups of 21, including Fujian screw 11, Lo, Jiangsu, Guangdong Lo 4. 5 different shell color apple snails AFLP analysis. By AFLP analysis of different shell color apple snails, yellow snails and black snails polymorphic loci ratio of 92.41% and 93.72%, respectively; Nei's gene diversity index of 0.3214 and 0.3327, respectively; Shannon's diversity index were 0.4819 and 0.4974; genetic diversity, yellow snails compared with the black screw 7 sites deletion. 6 different gender apple snails AFLP analysis. By AFLP analysis of different gender apple snails, the female screw and the male screw of polymorphic point ratio was 94.76% and 91.36%; Nei's genetic diversity index, respectively, to 0.3402 and 0.3222; Shannon's diversity information index was 0.5068 and 0.4816; genetic diversity, male screw and female screw 7 sites deletion. 7, different geographical populations apple snails genetic diversity ISSR analysis. By screening three ISSR primers for amplification of the three groups in Fujian, Jiangsu and Guangdong apple snails, a total of 33 clear sites of polymorphic loci ratio of 93.94%. Fujian, Jiangsu and Guangdong, three groups of polymorphic loci ratio .69.70%, 63.64% and 48.48%; Nei's gene diversity index were 0.2940,0.2387 and 0.1903; Shannon's diversity index were 0.4247,0.3536 and the 0.2796; groups are rich in genetic diversity, Fujian Lo genetic diversity highest Guangdong snails minimum. Genetic distance among populations of 0.1020-0.2158, the the screw, Fujian and Guangdong Lo genetic distance (0.1020), of Guangdong Lo Jiangsu Lo genetic distance (0.2158). The trend is consistent with the AFLP analysis results. 8, the palatability comparison of different geographical populations of apple snails of rice seedlings. Apple snails in southern China hazards crops are rice seedlings, experiments show that: apple snails are omnivorous snails, like feeding young green aquatic plants, in the case of other young green aquatic plants rice seedlings food intake rarely , and floating plants Azolla and duckweed Spirodela strong selective feeding with rice seedlings in paddy fields put the right amount of floating plants (Azolla and duckweed Spirodela, etc.) can be used as a to prevent apple snails hazard rice seedlings kinds of temporary measures.
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