中文摘要：

为明确葡萄霜霉病流行速率、空中孢子囊密度与环境因素之间的相关性,以感病品种红地球为试材,采用田间小区试验系统调查了沈阳地区葡萄霜霉病的流行动态,并对空中孢子囊密度进行定时捕捉,结合田间环境监测分析不同变量之间的相关性。结果显示,葡萄霜霉病的流行规律为：指数增长期为5月1日至7月23日,逻辑斯蒂增长期为7月23日至8月19日,衰退期为8月19日至葡萄生育末期。整个生长季葡萄霜霉病流行速率呈正态分布,其变化动态与该病害的流行时期特点基本一致。单季病害流行期,流行速率与温度、前5 d平均相对湿度均呈显著正相关,相关系数分别为0.442和0.409;在始发期和盛发期,空中孢子囊密度与流行速率、前5 d平均相对湿度、前5 d平均叶面湿润时数、前5 d积累降雨量基本均呈显著正相关,相关系数分别为0.753和0.768、0.836和0.651、0.651和0.834、0.954和0.747;与当日降雨量呈负相关,相关系数分别为-0.473和-0.542。表明上述与葡萄霜霉病流行相关性较高的因素可作为构建葡萄霜霉病预测模型的关键因子。

英文摘要：

To explore the correlation among epidemic rate,airborne sporangium density of Plasmopara viticola and environmental factors,using the susceptible variety ‘Red-globe ＇ as material,epidemic dynamics of grape downy mildew was investigated in field,airborne sporangium density of P. viticola and environmental factors were also monitored in field in Shenyang. Analyses of the variables showed that the epidemiological characteristics of grape downy mildew were as follows： exponential phase was from May 1st to July 23 rd,logistic phase was from July 23 rd to August 19 th,decline phase was after August 19 th. The epidemic rate of grape downy mildew appeared to be approaching normal distribution in the growth season,and its dynamics was consistent with epidemic period of the disease. Epidemic rate was in significant positive correlations with temperature and the average 5-day relative humidity in the growing season,where the correlation coefficients were 0. 442 and 0. 409,respectively. Airborne sporangium density was in significant positive correlations with epidemic rate,average 5-day relative humidity,average 5-day leaf wetness duration and accumulated 5-day rainfall in exponential phase and logistic phase,where the correlation coefficients were 0. 753 and 0. 768,0. 836 and 0. 651,0. 651 and 0. 834,0. 954 and 0. 747,respectively. Airborne sporangium density was in negative correlation with daily rainfall in exponential phase and logistic phase,where the correlation coefficients were- 0. 473 and- 0. 542,respectively.These factors could be used as key parameters of grape downy mildew forecasting model.