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In this paper ,the combination of indoor and outdoor observation was used as the method of studying the morphological characteristics of Evergestis extimalis Scopoli, the state of insect developmental period and damage characteriers, several kinds of pesticides was invest igated for controlling E.extimalis, establishment of integrated control technology demonstration area 1000 acres, comprehensive prevention and treatment area for three years up to 20 acres, pod victimization rate 10%. The results are as follows:Rape angle borer was widespread in Xining area. Occurrence of significant regional differences: altitude 2600 meters above the region sporadic rape angle borer, 2600 meters widespread. Mountain region in which happen light heavy, moderate occurrence River water areas, sporadic brain Hill. The temperature have greatly effected on egg hatching. Hot and dry summer is conducive to adult emergence, spawning, hatching. Continuous rainfall is not conducive to adult emergence. Appropriate early sowing can reduce the angle of borer damage. The crops of contiguous planting of the rape angle borer was infected, provide a better breeding place for future generations, Insect base increased, damage increased.Rape angle borer generations occur in a year in Xining, the mature larvae in the soil in the 20mm-50mm cocoon winter. In early May the following year, the overwintering larvae moved into the pre-pupa stage, in mid-May to enter the pupa stage, pupa duration of 30 days. Adult emergence began in early June unearthed. Adults appear from early June, early September finally see, the occurrence of about 90 days on the peak in mid-July. Adults with phototaxis, life 3-16 days; daytime habitat of the grass or potatoes, wheat, canola and other plants, a little alarmed they fly, flying is not strong; early June adults lay eggs in the main stem or lateral branch of rape in the upper part, pod, stalk angle, leaves, etc., of eggs laid in mid-July, the largest number of eggs per egg ranged from 1-13 grains, the average number of six eggs. Angle borer egg masses produced early yellow-green color, later turn into yellow, golden yellow, black and white (egg shell). Indoor observation showed egg duration 6-8 days. The field observation egg duration indicted 10-19 days. Borer larvae dispersed to find partly, bore into the young seed pods in damage. Field larvae damage occurs in early July. Larvae with silk and transfer habits, there are multiple victims pod holes. Each growth stage larvae in oilseed rape pods eat 4.5-8 months, 3-4.5 months or so to eat empty pod. Began in early august another mature larvae leave the host in the soil in winter cocoon knot soil. Scattered mature larvae have branches or pods wrapped silk net nest building habits.As the rape angle borer larvae length is only about 1 mm, and bore into the pod damage after hatching, the larvae investigated, so it is inappropriate as the basis for forecasting. Forecast to rape until the amount of egg pods initial field survey-based. Until the rape early one hundred egg pods totaled 40 blocks or more to chemical control. Control period to the early pod-based, egg mass can be even more anti-rape plots 2, an interval of 7 days. Through testing to determine the chemical control of oilseed rape angle borer pharmaceutical type, control time, control techniques. By the demonstration, the chemical control effect on a large area of prevention. Angle borer through rape drug test soil and deep plowing, sowing different angle borer damage survey test, good multi-frequency vibration-killing lamp prevention trials, summed up the rape angle borer integrated control technology.
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