(A) identify the symptoms
The main hazards leaves, shoots, young fruit can also be the pathogenesis. Leaf incidence, the positive anomalies occur translucent spots were light green or light yellow, brown lesion or the final into a reddish-brown and dry. Lesion into the neighboring connected polygonal large plaque. At the same time, Peronospora dorsal gray flakes grow. Shoot growth after the stagnation of the victims, dead or even distorted. Fruitlet influenza epidemics, the occurrence of off-white fruit Peronospora surface, growth stopped, cracking or falling.
(B) prevention and control measures
(1) early onset to peak, each spray interval 1 and a half times the Bordeaux mixture 1:0.5:180. Or 1000 กม 25% Swiss drug mycophenolate or 250 กม 40% had P-Al.
(2) removal of litter orchard concentrated burned.