VARIABILITY FOR REPRODUCTIVE AND VEGETATIVE TRAITS IN VACCINIUM MEMBRANACEUM

Abstract

Vaccinium membranaceum Douglas ex Torrey could be a valuable commercial crop if it could be domesticated, and a valuable genetic resource for highbush blueberry breeding. The broad objectives V. membranaceum project are: 1) to determine whether populations or individuals can be identified that perform well under a highbush blueberry management system in a typical production environment and 2) whether the unique fruit quality characteristics of this species can be incorporated into highbush blueberry. To address the first objective, 33 populations of V. membranaceum from Idaho, Washington and Oregon, were established in 1995, in Corvallis, Ore. in a randomized complete block design. Plants were evaluated for vegetative and reproductive traits, and for the incidence of rust (Pucciniasturm vaccinii [(G. Wint.) Jorst (syn. P. myrtilli Arth.)] and Phomopsis twig blight (Phomopsis vaccinii. Shear in Shear, N. Stevens, & H. Bain). Populations differed significantly for all traits except for fruit diameter in 2000, while year effects were significant. The incidence of the two diseases and date of first flower were the only traits that had a population by year interaction. This germplasm holds promise particularly for very early fruiting and for outstanding flavor. In order for this species to be commercialized as a crop it must be much more productive than was evident in this short term study. Twenty-six selections were made that are precocious, consistently fruitful, and produce good crops of medium to large berries on open, vigorous and disease free plants. These selections are being propagated for further evaluation and crosses between these and highbush blueberry have been unsuccessfully attempted.