Valsa

基本解釋

On Infectious Degree of 25 Species of Poplar by Valsa sordida Nits.
25種楊樹(shù)感發(fā)爛皮病程度的研究。
It is discussed the occurrence and harmfulness of valsa sordida of poplar in 4 aspects.
從4個(gè)方面論述了楊樹(shù)爛皮病的發(fā)生規(guī)律及危害性。
Cause of occurrence of apple tree valsa canker and its control
蘋(píng)果樹(shù)腐爛病發(fā)生與蔓延的原因及防治
Studies on Valsa Canker of Armandii Pine and its Control
華山松腐爛病及防治研究
A Study on the Control Index of Valsa Canker of Armandii Pine
華山松腐爛病防治指標(biāo)的研究