apple valsa canker

基本解释

The effects of S-921 strain (Streptomyces aureus) and its fermented broth on apple tree canker, Valsa mali, were tested by plating and free culture methods.
采用平板和离体培养法测定S-921菌株及其发酵液对苹果树腐烂病菌的作用。
It was revealed in an extensive survey that the occurrence of apple Valsa canker (Valsa ceratosperma) is correlated negatively with potassium content in bark.
矫治试验结果表明，春季增施钾肥，可提高树皮含钾量并减轻腐烂病发生程度。
But recently, the apple tree valsa canker caused by Cytospora spp occurred seriously and prevalently, which had became a threaten that held back the apple industry development.
然而，近年来苹果树腐烂病的普遍严重发生，已经对陕西苹果产业的顺利发展构成了严重的威胁。