| Diaphania perspectali(swalker),is sorted to Pyralidae,Lepidoptera,which distributes in Beijing and also north,east,northwest,centre,south of China. While it appears in Japan,Korea , India and other countries abroad. Diaphania perspectalis is the evil leaf-ate pest which is feed on courtyard ornamental named box.This pest occurred 3 generations in Shangdong provice,and the third little larva lives through the winter with its spin in leaf bud.It maily causes damage to box such as B. bodinier, Buxus slnica,Bucud hstlandii,which are all virescence plants. This thesis are composed of several experiments study including the response of development, survive , propagation of Diaphania perspectalis to temperature,the production of its life table,the measurement of its super-cooling point and ice point,the relations between entironment temperature and super-cooling point and ice point changes, and its chemical control . The main results are as follows.1 In the studied of the effect of temperature to the development, survive and propagation of Diaphania perspectalis, took quadratic parabola to fit the regression relations between the developmental period or rate of Diaphania perspectalis; determined the temperature of development beginning point and valid cumulative temperature applied the life table technique to set up Time-specific life table and Age-specific life table.1.1 The opening of the quadratic parabola between developmental period and temperature was up , the opening of the quadratic parabola between developmental rate and temperature was downward. At 27℃, developmental periods reached the lowest degree, and developmental rate reached the fastest dgree.1.2 At the range of 18~30℃, all stages livabilities of Diaphania perspectalis reached the peak at 27℃, when temperatures were higher or lower than 27℃, all stages livabilities decreased evidently.1.3 Total oviposition by one female adult and by one female adult a day ran to the peak at 27℃; 232.6667 granuies.1.4 At 27℃, the adults life was the longest, 10.5 d, when temperatures were higher or lower than 27℃, the adults life decreased , and the shortest at 30℃, 7.1667 d.2. 5 Calculated the start temperature and valid cumulative temperature by two methods, such as linear regression method and straight-way optimum method. the valid cumulative temperature of larva was the mostest , and the start temperature of larva was the lowest in the four stages .2. 6 By means of setting up two types of life table , we found out the relations between the life parameters of experimental population and temperature: the life expectancy of all ages assumed falling tendency with increase of ages; R0, rm,λand I all came at the maximum at 27℃, p.d.t ran to the minimum correspondingly. In the light of livabilities, oviposition by one female adult a day, adult life, R0 and I, the optimum theoretical temperatures for development were obtained, 21~27℃.2 In the study of the two experiments which included the determined of super-cooling point and ice point when Diaphania perspectalis lived through the winter and the relationship between entironment temperature and super-cooling point and ice point changes.The results are as follows.2.1 At the beginning of living through the winter, the super-cooling point and ice point of Diaphania perspectalis gradually went down and in the end of the winter then gradually went up.The super-cooling point of larva through the winter between October and November was apparently higher than that in September,which was apparently lower than that between December and January. In the February 2007,the super-cooling point went down to the lowest value(-22.03℃),while in the March the point went up to-16.35℃. The ice point of larva through the winter gradually went down between September and February next year,which meant from -2.57℃to -8.95℃。2.2 From the changes of the super-cooling point and ice point of Diaphania perspectalis,we found that the and ice point can went down along with the drop of environment temperature,and went up back along with the ascend of environment temperature.When the drops were in relative high temperature,the relations between the range of the dropped temperature and its drops of super-cooling point were not serious.However,when the drops were close to 0℃, the super-cooling point of Diaphania perspectalis fell rapidly along with the drop of environment temperature.It revealed that low temperature can induce the larva of the pests to promote the cold-resistant ability.This was accordant to the cold-resistant changes rule of many insects.The super-cooling point of Diaphania perspectalis fell rapidly to a very low point in the short time by low temperature domestication,which could ensure it to get through the cold winter.But the changes of its super-cooling point was later than the changes of temperature.In winter,the ice point went down gradually from September to January next year,is meant from -2.57℃to -8.19℃,which could be found that 5.62℃was dropped in all.,and the changes were relatively equality,lack of great changes.It showed that ice point changes of the pest was hardly ever effected by low temperature inducement,so it could not be used as the index of cold-resistant.Furthermore, the changes of ice point was also later than the changes of temperature of the winter larva,and the lowest value appeared in February.It would went up back after February which was similar to the changes of super-cooling point.3 The main conclusion of the single test on chemical control of Diaphania perspectalis3.1 The order of virulence to Diaphania perspectalis detected by several insecticides was 5%Chlorfluazuron SC,2.5% spinosad SC,5% Fipronil EC,5% Imidacloprid EC,48% Chlorpyrifos EC.The result showed that Regent and spinosad are the most perfect insecticides to control Diaphania perspectalis,so they were commended to be used on the virescence belt.3.2 The result of the outdoor,which was tested on effect of insecticide to Diaphania perspectalis ,showed that Regent and spinosad had better effect on controlling Diaphania perspectalis.It was worth to be commended to application because of the rapidness of the effect,the lasting ,safe to the human and animals and non-pollution to environment.Thereinto,the effect of control of 5% Regent 1000 fold could reach to 95.3%.Otherwise,spinosad was a bio-fountain insecticide which could be used to control other Lepidoptera pests.Its effects would be found intraday soon and its speed was much quickly than the normal slow effect insecticide.It would be slowly effect and more lasting if we used Imidacloprid to control Diaphania perspectalis.Because chlorfluazuron was used by people through and through,the pests had developed certain resistance,so the effect was not so good and it should be managed after controlling 7~10days,however, High toxin insecticides such asMethamidophos had been forbidden and restrictly used.It was proposed that Regent and spinosad should be extend to use to control Diaphania perspectalis.
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