稻瘟病的预测预报,叶瘟和穗颈瘟不同,一般讲叶瘟预测比较容易,发现病斑之后,再根据病斑型的变化、品种抗性和稻苗生长情况决定是否进行药剂防治。穗颈瘟必须在病害发生之前作出预测,因稻瘟病菌侵染穗颈,只有在抽穗前后,喷药防治也只有在这一段时间,待病菌侵入,症状出现之后,再行喷药防治便太迟了。因此,对穗颈瘟的发生流行趋势作出正确的预测,及早确定防治对象田,做好防治的准备工作,争取在病害发生之前喷药防治,才能收到良好的防治效果。目前我国对穗颈瘟的预测预报,尚无一套 Prediction and prediction of blast are different between leaf blast and panicle blast. Generally speaking, leaf blast is easier to predict. After the spot is found, the disease prevention and control is decided according to the change of spot type, variety resistance and the growth of rice seedlings. Panicle blast must be predicted before the disease occurs, because Magnaporthe grisea infection panicle neck, only in the heading, the spraying control only in this period of time, until the bacteria invade, the symptoms appear, then spray prevention and control too late. Therefore, it is necessary to predict the prevalence of panicle blast, determine the target field as soon as possible and make preparations for prevention and treatment before it can be sprayed and controlled before the disease occurs, in order to receive a good control effect. At present, there is not a set of predictions on panicle blast in our country