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- Author or Editor: Hugh A. Daubeny x
The indigenous North American red raspberry, Rubis strigosus has been neglected in breeding programs. Only four cultivars, `Cuthbert', `Latham', `Herbert' and `Ranere' provide most of the germplasm contained in present-day cultivars; no more than six individual wild genotypes of the species are represented by the four cultivars. In recent years, the B.C. breeding program has screened seedling populations of hitherto unexploited genotypes of the species from various locations in North America. Useful traits identified in selections from the populations include levels of resistance to 1) the North American aphid vector, Amphorophora agathonica, of the raspberry mosaic virus complex, 2) to several cane diseases and 3) to root rot caused by Phytophthora fragariae var rubi, as well as desirable fruit traits, such as bright, non-darkening red color and easy release. Selections with cultivar potential have now been identified in the second and third backcross generations from the species.
Abstract
Nineteen red raspberry cultivars were screened for immunity to Amphorophora agathonica, the aphid vector of red raspberry mosaic virus; ‘Reveille’ and ‘Pyne’s Royal’ were immune. The immunity of ‘Reville’ was derived from the ‘Lloyd George’ cultivar. ‘Pyne’s Royal’ appears to be a distinct source of immunity. Immunity of various selections appeared to be derived from one or more cultivars: ‘Lloyd George’, ‘Burnetholm’ and possibly ‘Pyne‘s Royal’ as well as the tetraploid ‘La France’. It is suggested that all cultivars developed in North America be screened for their reaction to A. agathonica prior to release.
Abstract
‘Sumas’ is a new strawberry cultivar released from the breeding program at the Agriculture Canada Research Station, Vancouver, B.C. In trials throughout the Pacific Northwest it has been noted for high yields and fruit qualities that compare favorably with those of ‘Totem’, currently the most widely grown cultivar in the region. Plants of ‘Sumas’ are winter hardy, show a high level of virus tolerance, and some resistance to red stele caused by Phytophthora fragariae Hickman. These traits will contribute to longevity of plantings. ‘Sumas’, an Indian word meaning “a big level opening,” now refers to Sumas Prairie, which is the fertile farm land at the eastern extremity of the B.C. Lower Mainland strawberry production region.
Abstract
‘Chilliwack’ and ‘Comox’ are new red raspberry (Rubus idaeus L.) cultivars released from the breeding program at the Agriculture Canada Research Station, Vancouver, B.C. ‘Chilliwack’ has been noted for its large, firm fruit with exceptionally high quality (Fig. 1). The fruit appear equally well-suited to fresh and to processing markets and have considerable resistance to both pre- and postharvest fruit rots, the former caused by Botrytis cinerea Pers. ex Fr. and the latter caused mostly by B. cinerea and Rhizopus spp. [probably R. stolonifer (Ehr. ex. Fr.) Vuill]. ‘Comox’ has been noted for its exceptionally high yields and, similar to ‘Chilliwack’, the fruit are large and firm and suited to fresh and processing markets (Fig. 2). Plants of both cultivars are highly resistant to Ampho-rophora agathonica Hottes, the aphid vector of the raspberry mosaic virus complex (RMV). In addition, ‘Chilliwack’ plants have some resistance to root rot, most likely caused by Phytophthora erythroseptica Pethyb.
Abstract
Reaction to cane Botrytis was determined for 43 red raspberry cultivars and selections and for seedlings of 25 progenies. Although there were some variations in relative reactions, it was possible to class the cultivars and selections as resistant or susceptible after examinations in at least two years. Segregations in the seedling populations suggested that two gene pairs might be involved in the reaction to the disease with the presence of at least two dominant genes necessary to give a resistant reaction. Postulated genotypes should be of predictive value in the choice of parents.
Abstract
Southwestern British Columbia, specifically the Lower Fraser Valley, is one of the world's leading producers of red raspberries (Rubus idaeus L.). About 2500 hectares produce the highest yields per unit area of any region in the world today. Production has increased in recent years because of the demands for red raspberry-derived products such as jam, yogurt, and juice as well as increased demand for fresh market berries.
Abstract
Variations in self-fertility, expressed as percentages of drupelets set, were observed among 69 red raspberry cultivars or selections. The incidence of reduced self-fertility was particularly prevalent among some of the older cultivars but was also observed in several selections. In a particular cultivar or selection reduction of self-fertility usually followed both self- and open-pollination. Reductions from self-pollination seemed mostly to involve self-incompatibility although at least one was due to reduced pollen-fertility. Reductions from open-pollination probably involved reduced numbers of functional embryo sacs.