Towards a Sustainable, Integrated Management of Apple Diseases

Abstract

Current understandings and guidelines for sustainable, integrated management of apple diseases are reviewed, and currently effective and sustainable tactics are discussed. Disease management in apples faces several critical problems not seen in other agronomic systems. As long-lived, clonal crops, fungicides and disease resistance play crucial roles in the management of apple diseases. Unfortunately, the pressure placed on these two strategies results in the development of fungicide resistance, and breakdown of host resistance. This review discusses the major diseases of apples, their management strategies, and the problems that have developed to impact sustainable apple production. Symptoms, causal pathogens, disease cycles and management practices are reviewed for primary diseases affecting apples in spring like apple scab, powdery mildew, fire blight and rust diseases. Problems due to fungicide resistance and availability of root stocks and cultivars for exploitation of plant resistance are discussed. Applications of cultural and chemical management with predictive models are also shown. Symptoms, disease cycles and management are also reviewed for summer diseases of apple, like bitter rot, flyspeck and sooty blotch