影响稻曲病严重度主要因素的研究

Study on Main Factors Affecting Severity of False Smut

本文通过在水稻的3个时期接种,发现最佳接种时期为破口前7 d,说明稻曲病菌的最佳侵染时期为水稻破口前1周。用正交试验对影响人工接种稻曲病发病率的条件进行研究。结果表明,水稻品种、播种时间、氮肥水平三因子里,对稻曲病发病严重度影响最大的是水稻品种,播种时间在不影响水稻正常生长时,越晚越有利于稻曲病发病。氮肥水平对稻曲病发病严重度的影响相对较弱。

Inoculation conditions for false smut of rice（ caused by Ustilaginoidea virens （Cooke） Tak）was studied under field condition. A- mong three inoculation stages of rice, the case inoculated 7 d before emergence of panicle resulted in optimum diseased effect, the best infec- tion period of U. virens was 7 d before emergence of panicle, and the factors affecting incidence rates of rice false smut were studied with or- thogonal design by means of artificial inoculation on field. The results showed that the varieties were the greatest factor of effect, the later so- wing time was helpful for disease occurrence, and the level of nitrogen fertilizer had less effect.