土壤温湿度及播种期对玉米丝黑穗病发生的影响

主要研究土壤温度、湿度及播种期与玉米丝黑穗病发生的关系。试验结果表明,土壤温度为21℃,玉米丝黑穗的发病率最高为31.3%,17℃低温下发病率为10.9%~16.7%,温度在24℃时,发病率为3.7%~4.8%;土壤含水量与病害侵染发病有较明显的关系,土壤湿度为15%时利于孢子萌发与侵染,发病率达为31.1%,湿度10%、20%时发病率仅为3.7%~8.8%,干旱和高湿不利于病菌孢子萌发,湿度是决定发病程度的主导因素。早播病害重,晚播病害轻但玉米产量低。

Effects of soil temperature and humidity on maize head smut

The relationship of soil temperature,soil humidity,sowing time and occurrence of maize head smut were studied.The results showed that the disease incidence of maize head smut was 31.3% when the soil temperature was 24℃.It was 10.9%-16.7% and 3.7%-4.8% when the soil temperature was 21℃ and 17℃,respectively.The soil moisture content was significantly related to disease infection.Soil humidity 15% was suitable for spore germination and infection and the disease incidence was 31.1%.When soil water content was 10% and 20%,the disease incidences were(3.7%) and 8.8%,respectively.Drought and high moisture is not good for spore germination and infection.Humidity is the main reason for occurrence of maize head smut.Early sowing caused severe disease.Late sowing could reduce disease but the yield was lower.Suitable sowing time is advocated.