基于田间空气中病菌孢子浓度的小麦白粉病病情估计模型研究

2014和2015两年度利用Burkard定容式孢子捕捉器监测了高感小麦白粉病品种京双16种植区和中感品种众麦2号种植区田间空气中的病菌孢子浓度变化动态,同时利用小型气象站监测了田间的气象因子,通过分析京双16和众麦2号种植区空气中孢子浓度与空气温度、湿度、降雨、风速和太阳辐射率的相关性,发现空气中的孢子浓度主要与空气温度呈显著的正相关性(r0.348 3,P0.05)。在此基础上,分别分析了田间病情与调查日期前累积孢子浓度、一周前累积孢子浓度、前一周累积孢子浓度和当周累积孢子浓度的关系,结果表明,中感品种众麦2号田间病情与累积孢子浓度的关系均呈指数关系,其中田间病情与调查日期前累积孢子浓度或一周前累积孢子浓度的拟合效果最好,而感病品种京双16的田间病情与累积孢子浓度多呈对数关系,其中病情指数与一周前累积孢子浓度的拟合效果最好。

Models of disease index estimation of wheat powdery mildew based on the concentrations of Blumeria graminis f. sp. tritici conidia in the fields

Daily sporec on centration of Blumeria graminis f. sp. tritici were monitored using Burkard volumetric spore samplers in the air of moderately susceptible variety Zhongmai2 and highly susceptible variety Jingshuang16 wheat fields in 2014 and 2015.Daily meteorological factors were recorded by meteorological station in the fields. The correlations were analyzed between spore concentration and meteorological factors, such as air temperature, humidity, rainfall, wind speed and solar radiation. The results showed that spore concentration was mainly positively and significantly correlated to air temperature(r>0.348 3,P<0.05). Then the correlations were calculated between disease index (DI)and four kind of accumulated spore concentrations, which were the accumulated spore concentration before the day of disease measuring, and the accumulated spore concentration before the current week of disease measuring, and the accumulated spore concentration in the previous week of disease measuring, and the accumulated spore concentration in the current week of disease measuring respectively. The data showed that there were exponential relationships between DI and the accumulated spore concentration in mo-derately susceptible variety Zhongmai2 wheat fields in 2014 and 2015, and the best DI estimating model was based on the accumulated spore concentration before the day of disease measuring or on the accumulated spore concentration before the current week of disease measuring; there were mainly logarithmic relationships between DI and the accumulated spore concentration in highly susceptible variety Jingshuang16 wheat fields in 2014 and 2015, and the best DI estimating model was based on the accumulated spore concentration before the current week of disease measuring.