两优培九稻曲病的发生及其与抽穗后温湿度的关系

分析了两优培九稻曲病的发病程度及其与抽穗后0～15d的平均气温和相对湿度的关系。结果表明，两优培九易感稻曲病。其发病率与抽穗后0～15d的平均气温呈显著正相关，温度是影响其稻曲病发生的主要气象因素，相对湿度起协同作用。提出了发病率为2％和5％时的温湿度指标。根据我国南方一季稻区18个城市42a(1951—1992)8—10月的气象资料，分析了稻曲病的易发区域和适宜抽穗期，为两优培九稻曲病的预防提供依据。

Incidence of Rice False Smut of Liangyou Peijiu and Its Relation to Temperature and Humidity after Heading

The relationship between the incidence of rice false smut and its corresponding temperature and relative humidity after heading was analyzed using a super hybrid rice, Liangyou Peijiu, as the material, and Shanyou 63 as the check hybrid. The results showed that Liangyou Peijiu was susceptible to rice false smut with its disease incidence significantly and positively correlated to the averaged temperature within 15 days after heading. Temperature was the primary climatic factor and relative humidity the secondary climatic factor which have an effect on the incidence of rice false smut of Liangyou Peijiu. The indices of temperature and humidity for 2% and 5% of diseased panicles of rice false smut were put forward. Based on the climatic data from August to October during 1951-1992 of 18 cities in the single cropping rice region of Southern China, the disease prone regions for the false smut and their corresponding safe heading stage were found, which will give a good evidence for preventing the incidence of rice false smut of Liangyou Peijiu in these rice regions.