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冬油菜是庆阳地区主要油料作物,年种植面积15万亩左右,但由于害虫种类多,危害严重,致使产量低而不稳。据我所1979年冬在西峰、宁县的14个乡镇24个自然村60块大田、290亩油菜地的调查,一般根蛆蛀害率18％～30％,严重受害株36％～68％。株虫数少则3～10头,多则高达50～60头。受害轻的植株可以越冬,受害重的植株大部分在越冬过程中死亡。由于根部受损,生长不壮,致使越冬死亡而翻耕改种,加上其它害虫的为害,使油菜成为本区产量很不稳定的一种作物,一般亩产仅50～100公斤,影响了油菜生产的发展。为
Winter rapeseed is the major oilseed crop in Qingyang, with an annual planting area of about 150,000 mu. However, due to the large number of pests and serious harm, the yield is low and unstable. According to my survey conducted in the winter of 1979 in 60 fields and 290 mu of rape in 24 villages of 14 townships and towns in Xifeng and Ningxian counties, the general rate of root-maggot decay was 18% -30% and that of the severely affected plants was 36% -68%. The number of strains of worms is 3 to 10, as many as 50 to 60 heads. The plants suffering from light damage can overwinter, and most of the heavily injured plants die during the wintering season. As a result of damaged roots and poor growth, which led to the death of overwintering and conversion of tillage and the damage of other pests, rape has become a very unstable crop in the area. Generally, only 50-100 kg per mu is affected, affecting Development of rapeseed production. for