第三代红铃虫是全年发生数量最多、为害最重的一代。一、二、三代的增殖比例为1∶4—10∶12—25。近17年中(1961—1979年)三代红铃虫大发生的有8年,平均百株累计有卵2238.1粒,铃害率84.22％,单铃虫道2.96头;中等发生的有7年,平均百株累计有卵684.5粒,铃害率70.64％,单铃虫道1.71头;轻发生的有2年,平均百株累计有卵215.7粒,铃害率31.55％,单铃虫道 The third generation of pink bollworm is the largest number of occurrences throughout the year, the most damaging generation. One, two, three proliferation ratio of 1: 4-10: 12-25. In the past 17 years (1961-1979), three generations of pink bollworm occurred for 8 years, with an average of 2238.1 eggs per hundred strains, with a boll damage rate of 84.22% and a single bollworm population of 2.96. For moderately occurring 7 years, There were 684.5 eggs on average and the boll damage rate was 70.64% and 1.71 bollworm alone. The incidence of light was 2 years. There were 215.7 eggs and 31.55%