设施黄瓜白粉病流行动态与预测模型

Epidemic dynamic and prediction model of cucumber powdery mildew under protected cultivation

通过持续监测2007—2019年设施黄瓜白粉病的田间流行动态,研究其田间流行规律并建立预测模型。结果表明,不同年份设施黄瓜白粉病盛发期时间总体较一致,春黄瓜、秋黄瓜发病最高峰分别为6月中旬、10月上旬;年度间的峰期持续时间、发生量差异较大,春黄瓜以2019年高峰期发病最重,秋黄瓜以2009年发病最重,2013年春黄瓜和秋黄瓜上均发病重但峰期持续时间短;该病的流行与气候条件密切相关,干湿交替频繁、冷暖起伏大的环境条件下发病重。在此基础上,根据该病害的田间系统调查资料及每年3—10月的气象因素,采用逐步回归分析法,建立了春黄瓜、秋黄瓜高峰期发生量预测模型。经拟合率检验,各模型均达75分以上的准确度,说明拟合结果与实测值相符,可用于瓜类白粉病的流行预测。

To determine the occurrence rule and prediction model,the field dynamic of cucumber powdery mildew under protected cultivation in Hangzhou during the years from 2007 to 2019 was investigated.The results showed that the peak period of the disease occurrence was very similar among different years.The powdery mildew severity in spring cucumber reached the highest peak in the middle ten days of June,while the occurrence of the disease would reach the peak in early October for autumn cucumber.There were significant differences in the peak duration and quantity of cucumber powdery mildew among years.The disease of spring and autumn cucumber led to peak quantities in 2019 and 2009,respectively.It was an unusual year in 2013 that the disease was found to be serious both in spring and autumn but short in the peak duration.In addition,it was found that the field dynamic of cucumber powdery mildew was closely related to the climate condition.For example,the disease would break out if the air temperature or environmental humidity exchanged frequently.Based on the monitoring data including the disease index of powdery mildew and climate factors from March to October every year,the prediction mathematical models of occurrence quantity for the disease in spring and autumn cucumber were established using the method of stepwise regression.Testing of the prediction accuracy of these models showed that the predicted values were consistent with the measured values and the scores representing prediction accuracy were over 75.Thus,these models could accurately predict the degree of occurrence for cucurbit powdery mildew.