目前对昆虫发生期的预报,是根据有效积温和平均温度进行的。对于美国白蛾,用平均气温预报较为可靠。因为有效积温很不稳定。比如,为使幼虫开始孵化所需要的有效积温可在160—170日度之间变化(发育标准为10℃时);也就是说,当所需要的有效积温平均为265日度时,最高和最低相差一倍多。所以我们在制定预报方法时,使用了 The current forecast of insect occurrence is based on effective accumulated temperature and average temperature. For the American white moth, with the average temperature forecast more reliable. Because effective accumulated temperature is very unstable. For example, the effective accumulated temperature needed to start larvae hatching can vary between 160 and 170 days (at 10 ° C); that is, the highest and the lowest when the average required effective accumulated temperature is 265 days Difference more than doubled. So we used it in developing forecasting methods