| Cnidocampa flavescens (Walker), Setora postornata (Hampson), Thosea sinensis (Walker), Parasa lepida (Cramer) and P. consocia (Walker) are common leaf-eating pests in city virescence in Shanghai. And the damage was serious in some areas based on investigation of common species of Limacodidae. This paper studied some items as follows: 1) the niche relationships of Limacodidae; 2) effect of environment on eclosion of adults living through the winter of C. flavescens and S. postornata; 3) the biology and ecology of P. consocia;4) the early-warning index system to calamity of pest in city virescence taking P. consocia for the example. The main contents and conclusions are as follows:1. In order to evaluate interspecific interactions of four species of Limacodidae in Shanghai urban greening, niche breadth, niche overlap, niche similarity and interspecific competition of C. flavescens, S. postornata, P. lepida and P. consocia were estimated in three dimensions: trophic, time and spatial resources array. The results showed that P. consocia used more hosts resources than other three pests used, and its Levins'breadth index was 0.5447. C. flavescens and S. postornata occupied more time resources with the niche breadth index 0.4304 and 0.4415 respectively. Cocoons of C. flavescens manifested the best spatial resources predominance and the niche breadth index was 0.5441. Interspecific relation showed that trophic resources between S. postornata and P. lepida were the adjacentest, and their niche overlap (2.6647), niche similarity proportion (0.5199) and interspecific competition index (0.7015) were all higher than that of others. Meanwhile, C. flavescens and S. postornata used time resources more closely than others used with the niche overlap index 0.4806 and competition index 0.5222 respectively. However, the niche overlap, niche similarity proportion and interspecific competition index of spatial resources between S. postornata and P. consocia were 2.7495, 0.9165 and 0.9959 respectively, and it showed that these two species were adjacentest on spatial resources using.2. The effect of temperatures, relative humidity, soil moisture and other main environment factors on emergence of hibernating generation adults of C. flavescens and S. postornata. The results showed that 20~30℃was the optimum temperature range of emergence of two species of Limacodidae, but the emergence rate of 15℃and 35℃was evidently lower. The highest emergence rate of two species of Limacodidae was 87.23 percent and 75 percent respectively. The eclosion schedule of the two species were different in different temperature. The eclosion fastigium of C. flavescens at 15℃, 20℃, 25℃, 30℃, 35℃was the fifth, the fourth, the second, the second and the third week respectively. The eclosion fastigium of S. postornata at 15℃, 20℃, 25℃, 30℃were the sixth, the fourth, the third and the second week respectively. The linear regression method and the Logisitic method both suited for analyzing the relationship of the eclosion schedule and temperature, and the terminal eclosion schedule of C. flavescens at 25℃was earliest with linear regression method, and the date was June 3th, while that of S. postornata at 30℃was earliest by linear regression method, and the date was May 30th. High relative humidity was benefit for eclosion of C. flavescens. The eclosion rate of C. flavescens was 81.00 percent in RH 80 percent and 84.00 percent in RH 90 percent, which was higher than the rate in RH below 70 percent. The eclosion rate of S. postornata was from 50 percent to 65 percent in the soil moisture from 10 percent to 40 percent, while the adults could not emerged in above the soil moisture 50 percent. The effect of relative humidity, soil moisture on emergence rate of progress is not evidently. Emergence rate of S. postornata in different depth of soil was different, and the rate was 10.00 percent under 5cm and 70.00 percent under soil 2cm.3. The morphology characteristics,life habits and life history in Shanghai were observed in nature and laboratory. This paper also researched mortality in hibernation and mensurated super-cooling point and freezing point of hibernating larvae of P.consocia. The results showed that average mortality in hibernation of P. consocia was 45.5% and average parasitism of Chrysis shanghaiensis was 28%. The super-cooling point during before winter,midwinter,after winter were -1.95℃,-4.32℃,-3.54℃respectively. 4. This paper also studied the spatial distribution pattern of hibernating cocoon of P. consocia on different plants in Shanghai by Iwao method, Taylor method models and some indices of aggregation (C,M,?M/?x,I,K,CA,I ? ), all indices indicated its distribution was in negative binominal distribution of an aggregated pattern in whole density, intensity of aggregation swells by density. The theoretical sampling number and Kuno's sequential sampling method were presented by the parameter of spatial distribution pattern.5. Feeding behavior and feeding amount of P. consocia were observed with Populus spp. The results showed that the larvae age of the first generation and second generation was 7 and 8 respectively. Average feeding amount per larva of the two generations was 167.71cm2 and 170.49cm2 respectively, and feeding period was 26 days and 27 days respectively. Feeding amount proportion of the final instar larvae was about 80 percent. The 4th and 5th larvae were the critical instars to control.6. Life tables of laboratory population of P. consocia were constructed at four temperatures. The result showed that the development rate increased with temperature increasing from 20℃to 30℃and the development rate of 3rd instar to 7th instar larva and pupa varied slightly at 35℃, but failed to be survival at 15℃. The relationship between development rate and temperature suit for Logistic model. The threshold temperatures and effective accumulated temperatures for egg to pre-oviposition and whole generation were 8.73℃, 10.22℃, 7.76℃, 15.19℃, 10.65℃, 13.04℃, 12.41℃, 11.79℃, 11.43℃, 8.79℃, 17.48℃and 8.75℃respectively, and 100.92,22.34,88.64,34.99,68.18,65.82,80.36,145.83,510.20,414.95,15.68,1159.30 degree-day respectively. The lifespan of adults were shorted with temperature increasing from 20℃to 35℃. Generally, lifespan of female was longer than that of male. The maximum number of eggs laid was 120.1 per female at 30℃, while the least number was 61.78 at 20℃. So the most suitale temperature range was 25℃to 30℃.7. The active factor life tables of natural population of the first generation of P. consocia was built, and the controlling effect of active factors was evaluated by using exclusion index of population control (EIPC) method. The results showed that the population trend indices was 4.10, and the EIPC of natural enemy, natural death, and NPV was 2.4447, 2.2044, 1.2398 respectively. So the natural enemy was the most important factor.8. Taking hazards of urban green plant pests as one kind of the important natural calamities, the early-warning index system of calamity of pest in city virescence was put forward. This system involved warning headstream, warning premonition and warning scene. Taking P. consocia for the example, the weight coefficient of each factor of the three factors was given. Then we calculated the integrated early warning index and risky grade. The warning grade of P. consocia was intermediate risky using yellow warning for issuing on forecasts. It should be controlled during the 3~4 instar larvae.
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