Identification of wild apple germplasm (Malus spp.) accessions with resistance to the postharvest decay pathogens Penicillium expansum and Colletotrichum acutatum

• Published in: Plant breeding Vol. 130; no. 4; pp. 481 - 486
• Main Authors: Jurick II, Wayne M., Janisiewicz, Wojciech J., Saftner, Robert A., Vico, Ivana, Gaskins, Verneta L., Park, Eunhee, Forsline, Philip L., Fazio, Gennaro, Conway, William S.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.2011; Blackwell
• Subjects: Acidity; Agronomy. Soil science and plant productions; Biological and medical sciences; Bitter rot; blue mould; Colletotrichum acutatum; Data processing; Decay; Economics; Fundamental and applied biological sciences. Psychology; Fungi; Gene pool; Generalities. Genetics. Plant material; Genetic diversity; Genetic resources, diversity; Genetics and breeding of economic plants; Germplasm; Malus; Pathogens; Penicillium expansum; Plant breeding; Plant material; Varietal selection. Specialized plant breeding, plant breeding aims; wild apple germplasm; Malus sylvestris; Ornamental shrub; Plant pathogen; Genetic resource; Rosaceae; Postharvest disease; blue mould; Fungi; Resistance; wild apple germplasm; Penicillium expansum; bitter rot; Dicotyledones; Pathogenic; Rot; Angiospermae; Genetic improvement; Wild plant; Spermatophyta; Mould; Fungi Imperfecti; Colletotrichum acutatum
• ISSN: 0179-9541; 1439-0523
• DOI: 10.1111/j.1439-0523.2011.01849.x

With 3 figures and 4 tables Penicillium expansum and Colletotrichum acutatum cause blue mould and bitter rot of apples during storage which results in significant economic losses. Resistance to these pathogens in commercial apple cultivars has not been documented in the literature. An apple germplasm collection, from the centre of origin in Kazakhstan, is maintained in Geneva, New York. This collection represents a more diverse apple gene pool than commercial cultivars and was evaluated for resistance to the pathogens that cause blue mould and bitter rot. Resistance reactions were skewed towards susceptibility for both fungi and comprised the majority of accessions examined. However, resistance to P. expansum was confirmed in select accessions over multiple years. Maturation patterns and quality indices for soluble solids and acidity, which may also affect susceptibility, were highly variable and represent the genetic diversity of the germplasm collection. Resistance in four accessions to C. acutatum and two accessions resistant to both P. expansum and C. acutatum are reported here for the first time. Data from this study will serve as a foundation for conventional apple breeding programmes and molecular genetics investigations to provide resistance against blue mould and bitter rot in commercial apple varieties.