Management of Valsa canker disease on fruit trees: can plant nutrition balance be potential solution?

Valsa canker disease causes significant losses in apple, pear, walnut, and other woody fruit crop production. The disease is caused by Cytospora fungi that infect opportunistically through natural wounds. Fungal infection can kill twigs, limbs, trunks and even entire tree. In field conditions, Valsa canker is difficult to control. Fruit trees with weak vigor, due to factors like old age, inadequate soil fertilization and canopy architecture are especially susceptible to the disease. Plant health depends on the balance of macro and microelements, and it has been long recognized that plant nutrient status can affect its ability to resist disease. This presentation will discuss the damage caused by the disease and practical management solutions for Valsa canker, the disease risk factors and the potential significance of plant nutrient balance strategy, and in particular, the crucial involvement of antifungal secondary metabolites in high potassium-mediated resistance against Valsa canker on apple.