Pyrus Species and Pear Cultivar Germ Plasm Collection in Oregon

Abstract

A previous report (7) emphasized that "single-clone specimen" Pyruscollections in arboretums and botanic gardens were generally unsuitable materials for use in agriculture. The genus consists of about 22 species, all of which are self-sterile, and thus require more than one clone of a species to obtain seedling populations for testing which are not inter-specific hybrids. Natural hybridization occurs readily in this genus, so that controlled crosses are needed for any plants used in research. During the past 10 years, we have collected seeds from wild Pyrusthroughout the world, and have established populations of each primary species at Corvallis (Table 1). Studies on rootstock potential, pest resistance and inheritance characteristics are underway (1, 2, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17). Materials were also made available to others for a number of different studies (3, 4, 5, in Table 2).