Valsa canker,caused by the fungus Valsa mali,is one of the most destructive diseases of apple in the primary production ......

Valsa canker,caused by the fungus Valsa mali, isone ofthe most destructivediseases of applein the primary production are......

Valsa canker, caused by the fungus Valsamali, is one of the most destructive diseases of apple in the primary production......