论文部分内容阅读
广东省的防治三化螟虫策略,过去重点是放在早、晚两造受害最重的第二代和第四代的防治上。但是由于第二、四代螟虫发生数量大、受害面积大,防治时机又紧迫,虽然大搞,用了很多农药,不一定受到如期效果,例如花县1963年第二代三化螟的防治运动称是空前的,但螟害白穗率仍达
The strategy of preventing and controlling stem borers in Guangdong Province was focused on prevention and control of the second and fourth generations which harmed the hardest and hardest in the past. However, since the second and fourth generations of stem borers occur in large numbers and the affected area is large, the time for prevention and treatment is urgent. Although many pesticides are used vigorously, they are not necessarily affected by the expected results. For example, the prevention and control campaign of the third generation of Borer in China in 1963 Known to be unprecedented, but borer white spike rate is still up