2008～2009年采用田间孢子捕捉法和随机区组设计对安徽省单季中稻区稻曲病菌（Ustilaginoidea virens）孢子释放规律、侵染时期和病害防治适期进行研究。结果表明，稻曲病菌孢子始见于7月中旬左右，第一个释放高峰出现在7月下旬至8月初，推测此阶段释放的孢子是初侵染的主要来源；8月下旬孢子释放量急剧增加，此时田间开始显症。晴天孢子以夜间(1:00、5:00)释放为主，白天孢子的释放量较少；阴雨天孢子全天释放，无明显释放高峰。以病菌菌丝+孢子悬浮液在剑叶露尖时接种，水稻不发病；在剑叶完全展开期至扬花期接种，发病率为1.2％～76.4％，其中以孕穗期（剑叶展开后5～6 d）接种发病率最高。药剂防治试验显示，水稻剑叶完全展开期施药防治效果最好，均在78.5%以上，提前或推迟施药防效均有所降低，故认为防治稻曲病的最佳时期是水稻剑叶完全展开期。
Spore releasing regulation and infection period of Ustilaginoidea virens were carried out by using spore catcher and randomized block design in 2008-2009, and the optimum period of controlling rice false smut in the single-middle-season rice area in Anhui Province was also studied. The results showed that spores appeared in around mid-July, and formed the first release peak in late July to early August. Spores releasing in this stage was the primary source of infection. After the appearance of symptom in late August, spores increased rapidly. The release was mainly at night (1:00-5:00 am) in sunny day, while in cloudy-rainy day, it would last all day long without a distinct peak. The incidence of rice was different when inoculated with hypha and spore suspension of U. virens in different growth periods. Inoculated at the exposing of flag leaf apex stage, rice was not infected; from flag-leaf-deployment to flowering, the incidence was from 1.2％ to 76.4％; in booting stage(5 days after the entirely expanding of flag leaves), the incidence was the highest. The control effects of fungicides spraying at flag-leaf-deployment stage were all over 78.5%, better than that in advance or delay. Therefore, the optimal time for controlling rice false smut was at flag-leaf-deployment stage.