河南省小麦白粉病流行原因和减灾对策

THE CAUSES OF WHEAT POWDERY MILDEW AND THE MEASURES OF DISASTER REDUCTION IN HENAN PROVINCE

本文阐述了河南省小麦白粉病流行成灾的特点、原因和发展趋势,指出今后数年内小麦白粉病的发生仍将严重,并提出了短期和长期减灾对策建议.

The characteristics of wheat powdery mildew expanded in Henan province in recentyears were:(1)The occurrence area was very large,which was more than ten million musfor an average year and was more than forty million mus for great occurrence year;(2)Theoccurrence range was very wide;(3)The epidemic frequency was very high;(4)The timeof powdery mildew appearance moved up;(5)The losses were very heavy.The causes:(1)The varieties of wheat in Henan were mostly susceptible powdery mildew;(2)The origi-nal infection quantity was very large;(3)The variation of cultivation conditions on wheatfield,such as fertilization and water,etc,was advantageous to the occurrence and epidemicof powdery mildew(4)The winter temperature leaned to warmth('greenhouse effect')andthe spring raininess was advantageous to the winter infection,breeding and the spring epi-demic of powdery mildew.In addition,it was advantageous to powdery mildew epidemic thatan amount of the farm chemical was not used rationally,and the ecologic equilibrium was de-stroyed.Moreover,it seems to be one cause that effective farm chemical was lack and theservise systems were not made perfect.It was forecast that wheat powdery mildew in Henanwould seriously occur.The short-term measures:(1)The resistance and susceptible varietiesshould be planted in proper proportions;(2)The nitrogen,phosphorus and potassium shouldbe used in proper proportions;(3)In serious disease area,the seeds should be dressed withthe seed coating formulations and triadimefon when sowing.Triadimefon was sprayed in thefirst tendays of April.The long-term measures:(1)Strengthen the breeding for wheat pow-derty mildew resistance;(2)Strengthen the cooperation research of wheat powdery mildewforecast.(3)Strengthen the farm chemidcal selection for replacing triadimefon.