Patial Distrbustion And Cold-hardiness Of Paridea Agulicollis Mostchulsky

Paridea angulicollis Motschulsky is Chrysomelidae, Coleoptera. It's main pest of Gynosttemma pentaphyllum Thumb. The research conducts a preliminary study about P. angulicollis adult ambling technique, spatial distribution patter and cold-hardiness. The results reveal the best sampling technique, spatial distribution in filed and adults cold-hardiness condition. This research provide a scientific basis for insect reproduction, occurrences, distribution, changing dynamic in next season and forecast and management decision-making. The results are as follows:1. Study on spatial distribution pattern and sampling technique of Paridea angulicollis adult in Gynostemma pentaphyllum.Among the five sampling methods, they were all suitable t–test. The parallel sampling method was the lowest error rate of 0.45, then the five point type and chessboard type; the lowest coefficient of variation was 1.455 9% of the parallel type. The spatial distribution pattern of P. angulicollis Motschulsky adult was aggregated and was density dependent. The aggregation was affected by some environmental factors and active process. By sampling mathematic model theory counted the best sampling number under different densities, errors and probability guaranteed in field investigation.2. Study on cold hardiness of Paridea angulicollis adultSuper-cooling point and freezing point: The super-cooling point and freezing point of P. angulicollis female and male adult are similarity in the same season, the female is a little higher than male and their diversity were not significant, but they were diversity in the different season; over-wintering stage was the lowest, the non-overwintering stage was more. There adult analyzing by Duncan's new multiple range method showed that the both October and November didn't have significant difference; May and July, July and September were a little bit significant difference; between May and July, September, October, November were significant difference at 0.01 level. The results indicated that cold-hardiness of the adults varied obviously with seasons. They showed significant difference at 0.05 levels.The water content in body: The water content in body result showed a distinct seasonal changes trend of P. angulicollis adult, they had positive correlation between the water content and the local temperature. The female water count lowed obviously male in overwintering stage and higher in non-overwintering stage. They had close relationship between the changes of water and cold hardiness, they had negative correlation. The result by regression analysis and T-test showed significant difference between the water content and the super-cooling point at 0.05 levels.The fat content in body: The fat content result showed a distinct seasonal changes trend of P. angulicollis adult, they had negative correlation between the fat content and the local temperature. The female fat content higher male between overwintering stage and non-overwintering stage.They had close relationship between the changes of fat content and cold-hardiness, they had positive correlation. The result by regression analysis and T-test showed significant difference between the fat content and the super-cooling point at 0.05 levels.Cold survival rate: Low temperature environment and exposure time were important factors influencing survival rate of P. angulicollis adult. They had different survival rate in different temperature environment and exposure time. Normally, the survival rate would induce following lower temperature and increase exposure time. The result showed the survival rate in 5℃, 0℃,-5℃obviously higher than -10℃,-15℃and 10h higher than 5d, 10d.L_T50 was one index of evaluation cold survival rate. The result showed the LT50 were more than 10d in 5℃&0℃; 5.422, 1.7978, 0.2156 in -5℃,-10℃&-15℃.we knew the lower the temperature, the shorter the L_T50.