气象因子对马铃薯晚疫病发生规律的影响

Effect of Meteorological Factors on Occurrence Regulation of Potato Late Blight

利用2008年在贵州盘县四格乡坡上村(海拔2 230～2 280 m)马铃薯不同品种晚疫病发生的大田试验资料,研究马铃薯晚疫病发生、流行的气象条件和动态特征以及产量损失程度.结果表明:4月下旬开始,当连续降雨日数超过5 d、日平均温度低于13℃、日平均日照时数不足4 h时,马铃薯晚疫病即将发生.5月下旬开始,当日降水量≥0.1 mm连续达5 d、日平均温度低于17℃、日平均日照时数不足3 h时,马铃薯晚疫病即将暴发、流行.马铃薯晚疫病流行的主要时期在5月下旬至6月中旬;威芋3号较会-2号偏重,其病指偏多0.4～19.8;平均产量未防治区较防治区损失9.63 t/hm2.同时提出了防治对策.

The meteorological condition of occurrence and epidemic of potato late blight and its yield loss were analyzed by using the late blight data of two potato varieties planted in Poshang village with an elevation of 2 230～2 280 m in 2008.The results showed that when the continuous rainfall days were over 5 d,mean daily temperature was below 13℃ and mean daily sunshine duration was less than 4 h from the last ten-day period of April,the potato late blight would emergence,and when the daily precipitation ratio of 5 continuous rainfall days was ≥0.1 mm,mean daily temperature was below 17℃ and mean daily sunshine duration was less than 3 h from the last ten-day period of May,the potato late blight would emergence seriously.The main epidemic period of potato late blight is from the last ten-day period of May to the middle ten-day period of June and the disease index of Weiyu 3 is 0.4～19.8 higher than Hui-2.The average yield of the un-control plot is 9.63 t/hm2 lower than the yield of the control plot.The paper puts forward the countermeasures for controlling potato late blight.