Potato rot nematode, Ditylenchus destructor Thorne, 1945, is a serious nematode pest in a number of root and tube crops, primarily in potatoes, and is an internationally quarantined pest (2). In garlic, it was only reported in Japan (3). In 2011, a survey was conducted for the stem and bulb nematode, Ditylenchus dipsaci (Kühn) Filipjev in Ontario, Canada. PCR analysis revealed that a population of Ditylenchus from one garlic (Allium sativum) bulb sample in a 0.81-ha field (2-acre) in the Ottawa area had a significantly longer ITS1 (approximately 100 bp) than that of D. dipsaci. Subsequent morphology and DNA sequencing concluded that the population was Ditylenchus destructor, a quarantine species in Canada. Twenty females and twenty males were fixed and permanently mounted for morphological studies. The main diagnostic characters matched the description of D. destructor by Thorne (4). The female stylets had strong knobs, 11.1 ± 0.9 (10 to 12) μm long, lateral fields with six distinct lines in the middle section of the body, excretory pore 4.7 ± 1.3 (3 to 6) μm posterior to the hemizonid, esophageal base bulb overlaps dorsally with the intestine, post-vulval uterine sac extends up to two-thirds of the vulva-anus distance, and tail terminus finely rounded. A total of 20 nematode individuals were used for the molecular studies. They had 5-bp differences with the ITS1 (GenBank Accession No. EF208210; 650 bp) sequence of an isolate from Sihong County, China. The sequence of the partial 18S gene (GenBank Accession No. AY593912; 864 bp) was identical to the sequence of an isolate of D. destructor in the Netherlands. The detection of stem and bulb nematode was also confirmed from the field. Infested garlic plants were stunted and the basal bulbs became dark and somewhat rotten. Prior to this finding in Canada, D. destructor was only reported in a few isolated locations in the province of Prince Edward Island (PEI) in 1946 (1). The nematodes in PEI were effectively controlled. Another suspected case in British Columbia was not confirmed since the infested field had been known to be infested with D. dipsaci. To our knowledge, this is the first report of D. destructor on the mainland of Canada. The infested field has been subjected to strict quarantine measures to prevent the spread of the pest. Reference: (1) A. D. Baker et al. Sci. Agric. 26:138, 1946. (2) EPPO. No. 123. Data Sheets on Quarantined Organisms. Bulletin OEPP/EPPO Bull. 8, 1978. (3) T. Fujimura et al. Jpn. J. Nematol. 8:22, 1989. (4) G. Thorne. Proc. Helminthol. Soc. Wash. 12:27, 1945.

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The strawberry production season can be extended in Ontario if plantings are protected from adverse weather conditions. At present, dayneutral cultivars developed in California are used for production, but are not well adapted to Ontario conditions. The objectives of this study were to determine suitable dayneutral cultivars for production throughout Ontario and to investigate how they react to high tunnel environments. Two sets of trials were run. The first set, planted in 2005 and harvested in 2005-2006, compared six dayneutral cultivars of strawberries in four environments. The second set, planted in 2010 and harvested in 2010-2011, compared five dayneutral cultivars grown in four environments. For the summer crops, high tunnels had higher yields in the cooler environment at New Liskeard and low yields in the warmer environment of Cedar Springs, when compared with outside plantings. In the spring, this trend was reversed. 'Seascape' and 'Tribute' performed consistently in all environments. 'Albion' and 'Monterey', although medium yielding with lower winter survival, had large fruit size and exceptional fruit quality. 'Portola', had large fruits and performed well, so could be of interest to farmers in Ontario. All the European cultivars tested had medium to small berries.

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Micropropagation of strawberries is an extremely effective tool to rid strawberry plants of Colletotrichum infections. The continued health of these plants depends on a vigorous sanitation program throughout the nursery system in North America. Propagating healthy strawberry plants requires a series of steps: plants are micropropagated, virus-tested, screened for fungal and bacterial pathogens, and finally grown under strict guidelines for two growing seasons in propagator's fields. In the propagator's fields, the plants are inspected for visual symptoms of diseases and checked for trueness-to-type. This paper reviews the protocols used to develop specific pathogen-tested strawberry plants in Ontario and, where appropriate, discusses alternate techniques.