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越南水稻种植面积约6百万公顷。在北部,水稻为冬春作及夏作雨季,大约有60%的种植品种为抗褐飞虱Ⅱ型;在南部,为冬春作、夏作和夏秋作三季,大约70%以上的品种为抗褐飞虱Ⅱ型品种,但其中有不少现今已经不抗Ⅱ型褐飞虱了。在北部以夏季稻褐飞虱为害重,总发生面积10万公顷左右。在南部每年有3个褐飞虱发生高峰,即1—2月份;7—8月份和10—11月份。在1990—1991年,一个诱虫灯,一个夜晚,最高曾诱到褐飞虱成虫达10万头。1973—1975年曾种植抗褐飞虱Ⅰ型的品种,如 IR1561、IR26、IR30等,
Vietnam has about 6 million hectares of rice planted. In the north, rice is spring-winter and summer-raining, with about 60% of the cultivars being resistant to BPH type Ⅱ; in the south, three seasons are winter-spring, summer and summer, about 70% of which are BPH Ⅱ type, but many of them now have no resistance to type Ⅱ brown planthopper. In the northern summer, the Nilaparvata lugens (Nilai) planthopper infestation rate is about 10 000 hectares. In the south, there are 3 brown planthopper peaks each year in January-February, July-August and October-November. In the period of 1990-1991, a trap light, one night, lured up to 100,000 BPH adults. 1973-1975 years have been resistant to brown planthopper type Ⅰ varieties, such as IR1561, IR26, IR30, etc.,