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从19世纪中期,苏联就有草地螟大发生的记载。在20世纪30年代曾几度大发生,此后很长时间受到控制,直至70年代又有回升,重新暴发为主要害虫。其发生特点:第一,在一个省区内一旦大发生,就不仅只发生一年,具有周期性连续发生的特点。如在乌克兰地区1972年开始严重发生后,1973年有所减轻,但到1974—1976年连续三年特大发生,虫口密度高达687头/米~2。第二,在大发生时,虽然来势很猛,蔓延面积较广,但其发生量的分布极不均
From the middle of the 19th century, the Soviet Union had records of great occurrence of grass borers. It took place several times in the 1930s and was then controlled for a long time until it rebounded in the 1970s and re-emerged as the major pest. Its occurrence features: First, once a big occurrence in a province, not only occurred only one year, with a cyclical occurrence of characteristics. As in the Ukraine, the area began to suffer serious damage in 1972, with some relief in 1973, but it took place for three consecutive years from 1974 to 1976 with an insect population density of 687 heads / m 2. Second, at a time of great occurrence, though the situation was very fierce and the area of spread was relatively wide, the distribution of its occurrence was extremely uneven