摘要
分析结果表明,呼市地区露地黄瓜霜霉病一般在6月下旬开始发病,7月上中旬病害开始流行。黄瓜霜霉病的发生与流行与6月下旬至7月下旬的旬平均湿度和累积降雨量以及连续5d 以上的阴雨天关系密切。旬平均相对湿度高于72％,累积降雨量高于152.8mm 以上,为重发生年;二者条件具一,为中发生年;连续5d 以上的阴雨天,会促使病害加重发生。旬平均湿度低于60％,降雨量低于90mm 以下,病害为轻发生年或轻微发生年。呼市地区6月下旬～7月下旬的旬平均温度为20.9℃～22.5℃,均是适于病害流行的最佳温度。
Analysis result showed that Pseudoperonospora cubensis often occurred in the last ten-day of June and developed in the first ten-day of July to the middle ten-day of July in Huhhotcountry-side.Occurrence and develpoment of the disease had close relations with average humidity ofthe period,accumulated rainfall and more than five-day of overcast and rainy weather duringthe last ten-day of June to the last ten-day of July.The disease development in a year will be serious when everage humidity of the period ismore thn 72 per cent and accumulated rainfall is higher than 152.8mm.The disease developing will be less serious in the condition of either over 72 per cent rel- ative average humidity or over 152.8mm accumulated rainfall.But more than five-day of overcast and rainy weather will promote the disease spread-ing.The disease will spread slightly in a year when average humidity of the period of ten-dayis less than 60 per cent and accumulated rainfall is bess than 90mm.Average temperature of the period of ten-day is 20.9℃ to 22.5℃ in the last ten-day ofJune to the last ten-day of July in Huhhot countryside,which is optimum temperature forPseudoperonospora cubensis development.
关键词
黄瓜
霜霉病
气象条件
cucumber downy mildew
humidity
rainfall overcast
epidemic
forecasting
