红三叶白粉病田间分布型的研究

STUDY ON FIELD DISTRIBUTION PATTERN OF RED CLOVER POWDERY MILDEW

The methods of linear regtession eguation mean Crowding(m~*)on mean number of infected branches(X)were used to study the field distribution patterm of red clover branches infected by powdery mildew(Erysiphe polygoni)and that of their infectiosity classes,in this paper.The tesults show that the field distribution patterns of both infected branthes and their infectiosity classes were aggregative ones,with obvious infecting centre,while there was a regular distribution in intra-colony,instead.