Resistance to blighting by Monilinia vaccinii-corymbosi in diploid and polyploid Vaccinium species

Abstract

Resistance to blighting by Monilinia vaccinii-corymbosi (Reade) Honey was evaluated under greenhouse conditions in multiple populations of the diploid species Vaccinium boreale Hall & Aalders, V. corymbosum L., V. darrowi Camp, V. elliottii Chapm., V. myrtilloides Michx., V. myrtillus L., V. pallidum Ait., and V. tenellum Ait., as well as in accessions of the polyploid species 4x V. hirsutum Buckley and 6x V. corymbosum f. amoenum Aiton. Significant species differences were found in mean blighting levels averaged over 2 years, with values ranging from 3.5% for V. boreale to 49.2% for 2x V. corymbosum, compared with 27.5% for the resistant 4x V. corymbosum check, 'Bluejay', and 64.3% for the susceptible 4x V. corymbosum check, 'Blueray'. Wild Vaccinium species may serve as new sources of resistance to blighting, if resistance can be transferred easily and horticultural type recovered.