Genetic analysis of resistance to powdery mildew (podosphaeara leucotricha) in apple (Malus x dornestica Borkh.)

Abstract

Apple powdery mildew, caused by Podosphaera leucotricha, is one of the major diseases of the cultivated apple in the Western Cape, causing severe losses in yield and affecting fruit quality. This affects the deciduous fruit industry as costs are incurred on the management of this disease. The application of fungicides is one of the strategies mostly used to control the spread of the pathogen. Since consumers demand high quality fruit with no harmful chemical residues, alternative approaches that minimize the reliance on agri-chemicals for the control of this disease must be developed. Marker-assisted breeding for the development of new varieties that exhibit durable resistance to the fungus is the best and safest way to reduce damage caused by powdery mildew.