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Blackleg, caused by the fungus Leptosphaeria maculans, is an important disease of canola. Both ascospores and pycnidiospores of the fungus can infect intact leaves under conditions of extended leaf wetness, with infection then progressing further into the stem. In western Canada, spring is typically cool and dry and additional factors may be involved for successful infection. This study was designed to assess the effect of wounding and wound age on cotyledon infection, to evaluate the likelihood that flea beetle-feeding injuries could contribute to increased disease. Infection of canola cotyledons occurred readily via mechanical wounds in the absence of leaf wetness when seedlings were spray inoculated with pycnidiospores of L. maculans, whereas no infection occurred on intact cotyledons even under 6-h leaf wetness. Wound age also played a role in susceptibility; wounded tissues were less susceptible when plants were kept in a greenhouse for 8 h or longer before inoculation, with substantially reduced infection success relative to fresh wounds. This wound-age effect was similar on susceptible and resistant canola varieties. A high temperature (25°C) seemed to favour the healing of wounds, reducing susceptibility when compared with control (21/16°C) and low (10°C) temperatures. Leaf wetness post-wounding may hinder healing, and high post-inoculation humidity (80–90% relative humidity) increased infection via older wounds slightly, relative to lower (50–60%) relative humidity. These data provide a rationale for studying the effect of improved flea beetle control on early L. maculans infection of canola. [ABSTRACT FROM AUTHOR]

The pea (Pisum sativum L.) is an excellent protein source for livestock and human nutrition. However, its growth is hampered by several factors including powdery mildew (Erysiphe pisi DC) and lodging in irrigation areas. These limitations may be solved through combining a Canada powdery mildew-resistant pea (Mp1807) with green cotyledon cultivar (Graf) by means of sexual hybridization. A bred semi-leafless pea, cultivar Longwan No. 6, was selected and evaluated in multiple ecological zones to investigate and evaluate high-yield, adaptability, and resistance to root rot (Aphanomyces euteiches Drechs. f. sp. pisi) and powdery mildew from 2012 to 2014. The results revealed that Longwan No. 6 was characterized by lodging resistance and moderate powdery mildew resistance. The average grain yield of Longwan No. 6 is 2855.3 kg/hm2 in spring sowing and is increased by 18.4% compared to the control cultivar (Longwan No. 1). The average grain yield of Longwan No. 6 is 2349.9 kg/hm2 in winter sowing and is increased by 12.8% when compared to the control cultivar. The results indicated that Longwan No. 6 has a greater potential to increase yield and wide adaptability. Adopting the Longwan No. 6 pea cultivar contributes to improvements in pea production in irrigation areas. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Blackleg, caused by Leptosphaeria maculans, is a serious disease on canola or rapeseed in Canada, Australia and Europe. Disease levels have increased in western Canada recently and additional tools are needed to improve blackleg management. Seed treatment can be a cost-effective approach against blackleg, but there is currently no registered seed-treatment product targeting aboveground blackleg infection. In this study, a range of fungicides was evaluated for control of cotyledon infection by L. maculans and blackleg of canola. Under controlled environmental conditions, fluopyram showed greater efficacy than fluquinconazole (used against blackleg in Australia) in limiting cotyledon infection, while Prosper® EverGol and Helix® Vibrance (industry standards) were ineffective. Fluopyram at a rate of 30–150 g/100 kg seed generally inhibited cotyledon infection and this efficacy was not affected by delayed soil moisture for 3 weeks after planting. This indicates that the efficacy will unlikely be affected by a slight delay in germination due to a soil moisture deficit after seeding. In addition to typical mechanisms of succinate dehydrogenase inhibitor fungicides, fluopyram also induced expression of the indicator gene coding PR-1 proteins substantially, indicating the potential for inducing disease resistance. In field trials at 75 and 150 g/100 kg seed, fluopyram reduced the infection on cotyledons resulting from pricking inoculation on both susceptible and resistant canola cultivars, potentially limiting the infection into the stem. These seed treatment rates reduced the disease severity index (DSI) substantially on the susceptible cultivar, while DSI was low on a resistant cultivar with or without fluopyram treatment. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)