The raspberry aphid, Amphorophora agathonica Hottes, is the principal vector for four viruses in the Raspberry mosaic virus complex which contributes to field decline and crumbly fruit symptoms in red raspberries (Rubus idaeus L.) in the Pacific Northwest. Breeding for aphid resistance has been a major emphasis in raspberry breeding in British Columbia since the 1960s. The most widely used resistance gene in the breeding program, Am, broke down in 1990. The appearance of additional resistance-breaking aphid biotypes since then has resulted in the need to identify new sources of resistance and develop approaches for maintaining their durability. We surveyed aphids from commercial fields in the Fraser Valley of British Columbia and identified seven biotypes of A. agathonica as determined by a differential set of cultivars and selections. Every cultivar released by the program to date is susceptible to one or more biotypes, though biotypes A and B, which are only capable of colonizing plants with no identified resistance (A) or with resistance from 'Newburgh' (B), appear to be the most common. A single aphid isolate capable of aggressively colonizing strawberry (Fragaria xananassa Duch.) in addition to raspberry was also identified, opening up the possibility of virus exchange between these species. Several sources of resistance in wild raspberry germplasm have been identified and current efforts are aimed at identifying markers for unbroken resistance sources to aid in effectively pyramiding resistance genes to slow the breakdown of resistance. Existing sources of resistance and the current status of knowledge on each will be presented as well as instances of apparent genetic drift of aphid colonies in the greenhouse.

Phytophthora root rot caused by Phytophthora rubi ((Wilcox & Duncan) Man in't Veld) is a disease that limits the production and longevity of raspberry fields throughout the world. Natural plant resistance to the pathogen is available in some cultivars and in some related species of Rubus, and plant breeders are working to incorporate this resistance into commercially acceptable cultivars. Because the disease can be patchy and slow to appear in the field, a more rapid and standardized method of screening selections in the greenhouse was developed at the Agriculture and Agri-Food Canada Research Centre at Agassiz, British Columbia. P. rubi was isolated from two raspberry fields exhibiting root rot symptoms, and these isolates were used in the screens. Test plants were raised in tissue culture and inoculated with macerated hyphae of the pathogen, in a semi-hydroponic system in the greenhouse. After incubation under flooded conditions, roots were rated for root rot severity. The process is relatively rapid and has consistently discriminated known susceptible cultivars from known resistant cultivars. The screenings have identified new sources of resistance in clones that are derivatives of R. strigosus, R. niveus, R. lasiostylus and R. innominatus. A new source of resistance has also been identified in a clone of the Korean black raspberry R. coreanus.

The root-lesion nematode Pratylenchus penetrans is a pathogen of red raspberry (Rubus idaeus). A field experiment was initiated in 2003 to determine the effects of organic mulches of two different composts, broiler manure, and shredded paper co-applied with broiler manure, on (i) the abundance of P. penetrans, (ii) free-living nematodes as indicators of soil food web structure, and (iii) root biomass and early productivity of 'Malahat' red raspberry. The organic mulches were applied each year at rates estimated to provide the 1.5 m wide root zone strip with approximately 133 kg.ha(-1) of potentially available nitrogen. The nonmulched control was fertilized each year with urea at 133 kg N.ha(-1). Soil samples were taken from the root zone for root biomass and nematode analyses at five dates during the 2005 and 2006 growing seasons. Population densities of P. penetrans in soil were lower and root biomass was greater under one of the composts and the shredded paper - broiler manure mulch relative to the nonmulched treatment. Fine root biomass was negatively correlated with P. penetrans per gram root. The abundance of omnivorous and predacious nematodes was negatively correlated with P. penetrans population densities and positively correlated with root biomass. The data are consistent with our hypothesis that organic mulches increase soil food web structure and the abundance of nematode antagonists (e.g., predacious nematodes), resulting in reduced crop damage by P. penetrans. However, we cannot rule out the possibility that the improved raspberry root growth and primocane productivity was the result of beneficial changes in soil chemical properties, such as increases in exchangeable calcium and pH.

Previous observations of strawberry roots of plants grown in peat-based medium in a screenhouse or grown in the field in soil indicated that genotypes differ in root length and volume. This experiment was designed to evaluate a large number of genotypes to better quantify this variability and to identify those genotypes with large root systems. Plant material consisted of 100 cold-stored dormant genotypes and 71 micropropagated genotypes. Plants were grown for 8 weeks in a greenhouse, then dry weights of shoots, roots and stolons were obtained. For the cold-stored plants, root dry weight ranged from 0.74 g for 'K99-5' to 2.18 g for 'Brunswick'. The shoot-to-root ratio ranged from 2.51 for 'K03-2' to 5.43 for 'K99-36', with a mean of 3.51. For the micropropagated plants, root dry weight ranged from 0.26 g for 'BC4-41-67' to 2.14 g for 'WSU2464', with a mean of 1.01 g for 71 genotypes. The shoot to root ratio ranged from 2.01 for 'BC92-20-85' to 6.72 for 'BC4-9-5', with a mean of 4.44 for 70 genotypes. Genotypes identified in this study as having large root systems or small shoot:root ratios can be used to test whether these types are more tolerant of root pathogens or abiotic stresses.

The Pacific Agri-Food Research Centre (PARC) breeding programme supports the raspberry growing industry throughout the Pacific Northwest (PNW). Of special interest is the development of cultivars adapted to both the processing and fresh markets and with resistance or tolerance to diseases and pests. The most important pests include raspberry bushy dwarf virus (RBDV), the North American aphid vector (Amphorophora agathonica Hottes) of the raspberry mosaic virus complex (RMV), root rot (mostly caused by Phytophthora fragariae var. rubi Wilcox & Duncan), and post harvest fruit rot (mostly caused by Botrytis cinerea Pers. ex Fr.). Earlier releases which have met with success include 'Tulameen', now the most extensively planted fresh market cultivar in the world, as well as 'Qualicum', 'Chilliwack', 'Skeena' and 'Chilcotin'. Recent releases include 'Malahat', which has become the leading cultivar in the PNW for the early fresh market and is also adapted to machine harvesting for the processing market, and 'Cowichan', which appears to escape the pollen-borne RBDV and is equally suited to both processing and fresh use. Other recent cultivars are 'Chemainus' and 'Esquimait'. 'Chemainus' is suited to both market outlets, whereas 'Esquimait' is best suited to the late fresh market. 'Saanich', another multi-purpose cultivar, is the most recent release and is particularly well-suited for the IQF market. Advanced selections, including several with genes derived from hitherto unexploited selections of the North American red raspberry, Rubus strigosus Michx (R. idaeus subsp. stirgosus Michx.), will be discussed.

The goal of this study was to determine the level of genetic diversity and relatedness among 16 strawberry (Fragaria H ananassa Duch.) cultivars and 11 breeding lines developed in Canada, using Inter Simple Sequence Repeat (ISSR) markers. Seventeen primers generated 225 polymorphic ISSR-PCR bands. Cluster analysis by the unweighted pair-group method with arithmetic averages (UPGMA) revealed a substantial degree of genetic similarity among the genotypes ranging from 63 to 77% that were in agreement with the principal coordinate (PCO) analysis. Geographical distribution for the place of breeding program explained only 1.4% of total variation as revealed by analysis of molecular variance (AMOVA). The ISSR markers detected a sufficient degree of polymorphism to differentiate among strawberry genotypes, making this technology valuable for cultivar identification and for the more efficient choice of parents in current strawberry breeding programs. Key words: Fragaria × ananassa, DNA fingerprinting, multivariate analysis, breeding, genetic similarity

The vegetative and reproductive potential of six red raspberry (Rubus idaeus L.) cultivars developed at the Agriculture and Agri-Food Canada (AAFC) Pacific Agri-Food Research Centre (PARC) at Agassiz, British Columbia, Canada ('Chilcotin', 'Chilliwack', 'Comox', 'Haida'. 'Nootka' and 'Skeena') were evaluated in the Belgrade region of Serbia from 2001 to 2004. 'Willamette' was used as a standard of comparison. 'Comox' and 'Skeena' produced greater fruit yield (12.5 t.ha(-1) and 16.7 t.ha(-1), respectively) than 'Willamette' (2.2 t.ha(-1)). Absolute minimum temperatures of - 14 degrees C. recorded in January 2002 and 2003, as well as temperature fluctuations and drought periods may have reduced fruit yield of 'Willamette'. The mean height of 'Haida' dormant primocanes was about 0.5 m shorter than that of 'Willamette' primocanes, but it out-yielded the standard cultivar.

In a trial in Northern Serbia, six raspberry cultivars from the AAFC-PARC breeding program were tested against 'Wilamette', the leading raspberry cultivar grown in Serbia. These six included 'Chilcotin', 'Chilliwack', 'Comox', 'Haida', 'Nootka', and 'Skeena'. It was found that 'Comox' and 'Skeena' cultivars exhibit desirable pomological traits such as high fruit quality and low susceptibility to major diseases and pests. Based on the results from this trial, 'Comox' and 'Skeena' are recommended for further testing throughout the Belgrade region to determine the potential role of 'Comox' and 'Skeena' in the expansion of red raspberry production in the region.

Nitrogen (N) is important for sustained production of raspberries. Inorganic (e.g., commercial) and organic (e.g., manure, compost) applications are common, often resulting in applications of N in excess to that required by the plant for intensive production situations resulting in pollution of groundwater with nitrate. During the development of a simulation model for evaluating N use for raspberry production, data for the N content of dormant cane materials were not available. Floricane materials and primocane prunings are often chopped and returned to the soil. Dormant-cane material was sampled in a cultivar breeding trial plot. The amount of the various materials and their N and carbon (C) concentrations differed among cane types (floricane stems and laterals, and primocanes) and cultivars. The C:N ratio of some of these components was quite high (> 130), which would likely cause at least temporary immobilization of inorganic N by microbes in the soil and reduce N that is available to the plant. The implications of the amount and quality of dormant cane materials of different cultivars to N cycling in raspberry require the assessment of the interaction of soil transformation and plant uptake processes such as the application of simulation models. This understanding is necessary for the development of N management practices that balance sustained high yields while minimizing nitrate pollution potential.

idaeus, fruit breeding, fruit quality, fresh market, yield, disease resistance 'Esquimalt' (Fig. 1) is a new fl oricane-fruiting red raspberry (Rubus idaeus L.) cultivar

‘Cowichan’ (Fig. 1) is a new fl oricane-fruiting red raspberry (Rubus idaeus L.) cultivar from the breeding program at the Pacifi c AgriFood Research Centre (PARC) of Agriculture and Agri-Food Canada (AAFC), Agassiz, B.C. ‘Cowichan’ produces high yields of large, relatively fi rm fruit suited to machine harvest. It is adapted to both the processing and fresh markets. It appears to escape infection from the pollen-borne raspberry bushy dwarf virus (RBDV) and might be resistant or immune. It is resistant to the common strain of the North American aphid vector, Amphorophora agathonica Hottes, of the raspberry mosaic virus (RMV) complex. ‘Cowichan’ is the name of a lake on Vancouver Island and follows the tradition of naming PARC berry cultivars with B.C. First Nations names. ‘Cowichan’ translates as warmed by the sun or warm country.

‘Marion’ is currently the most important blackberry (Rubus L. subgenus Rubus) cultivar in the world as it is the predominant cultivar grown for the processed fruit market (Finn et al., 1997). ‘Chester Thornless’ was probably the most important fresh market blackberry in the world in the 1990s (Clark, 1992; Strik, 1992). However, since that time hundreds of acres of ‘Navaho’ in the midwestern U.S., ‘Tupi’ and ‘Brazos’ in Mexico, and proprietary cultivars around the world (J. Clark and C. Fear, personal communication) have been planted. The erect cultivars (e.g., ‘Navaho, ‘Apache, ‘Arapaho, and ‘Cherokee) and semi-erect cultivars (e.g., ‘Chester Thornless’, ‘Hull Thornless’, and ‘Triple Crown’) have been primarily grown for fresh market sales and the trailing cultivars (e.g., ‘Marion’, ‘Kotata’, and ‘Waldo’) for processing. However, there are some exceptions. ‘Olallie’, a trailing blackberry, was a major fresh-market cultivar in California for local sales and long-distance shipping until about 2001 (R. Harrison, personal communication) and, more recently, ‘Siskiyou’, which is produced along the West Coast, has proven adapted to long distance shipping. In the past, the erect and semi-erect blackberries have typically had better fi rmness and skin toughness and black color than the trailing cultivars, but the trailing cultivars have generally had better fl avor and are more pleasant to eat (perception of smaller or fewer seeds). The USDA–ARS Description and Performance

Strawberries and raspberries are crops that are traditionally produced in the field. Recently, a desire on the part of consumers for year-round fresh berries has stimulated 'out-of-season' production around the world. A brief review will be presented on the developments in 'out-of-season' production of berries in greenhouses and plastic tunnels. Forcing practices, cultural and production systems will be described. Other important aspects of protected cultivation such as dormancy and chilling requirements, forcing floricanes and primocanes raspberries and the use of bumblebees for pollination will be discussed.