Postharvest Rhizopus Fruit Rot Resistance in Red Raspberry1

Abstract

Abstract Fruits of 37 red raspberry ( Rubus idaeus L.) cultivars and selections (all subsequently referred to as clones) were screened for postharvest resistance to Rhizopus spp. (probably R. stolonifer [Ehr. ex Fr.] Vuill.) at Abbotsford, British Columbia and Puyallup, Washington. Among clones examined at both locations the more resistant were ‘Meeker’, ‘Nootka’, and selections 6820/54 and 6820/41 from the Scottish Horticultural Research Institute (SHRI) and the more susceptible were ‘Mailing Leo’, ‘Skeena’, ‘Haida’ and SHRI 7023/69. In addition at Abbotsford, ‘Matsqui’ and several British Columbia (BC) selections were resistant, and ‘Mailing Delight’, ‘Canby’, ‘Glen Clova’ and several BC selections were very susceptible. Two sources of resistance were apparent: intrinsic tissue resistance in clones with relatively soft fruit derived from the ‘Cuthberť cultivar, for example ‘Meeker’, ‘Nootka’ and ‘Matsqui’, and resistance associated with fruit firmness in clones derived from the black raspberry ( R. occidentalism , for example SHRI selections 6820/54 and 6820/41.