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Industrial hemp (Cannabis sativa L.) is a multipurpose crop for which there is growing interest in Canada. There is, however, currently limited information on the adaptation and production potential of government approved cultivars in eastern Canada. Eleven cultivars were evaluated in terms of biomass and seed yields and composition, when grown in seven contrasted environments in the province of Québec. Dry matter yields varied considerably across cultivars and environments, ranging between 172 and 8837 kg ha−1 (average of 3226 kg ha−1) for biomass, and between 47 and 3781 kg ha−1 (average of 1315 kg ha−1) for seeds. Despite the presence of cultivar × environment interactions for both biomass and seed yields, the cultivars Anka, Ferimon, and Jutta consistently produced high yields across environments. Averaged across environments, these cultivars respectively had biomass and seed yields of 4591 and 1397, 5827, and 1878, and 4096 and 1408 kg DM ha−1. Limited variation was observed among cultivars in terms of composition. Cellulose was the largest biomass constituent (average of 562 g kg−1 DM across cultivars and environments), followed by hemicellulose and lignin (averages of 123 and 93 g kg−1 DM, respectively), while seed crude protein (CP) and oil (ether extract) concentrations averaged 237 and 288 g kg−1 DM, respectively. Considerable variation in yield potential and adaptation were observed among the cultivars of industrial hemp evaluated in the province of Québec; while biomass yields were moderate, the seed yield potential appears to be high locally compared to western Canada.Core Ideas Biomass and seed dry matter yields of the 11 industrial hemp cultivars evaluated varied considerably across cultivars and environments. Despite the presence of cultivar × environment interactions for biomass and seed yields, some cultivars consistently produced high yields of both biomass and seeds. Limited variation was observed among cultivars in terms of biomass and seed chemical composition.

Agricultural practices affect the biotic and abiotic conditions that determine food and shelter for carabid beetles (Coleoptera: Carabidae). We hypothesised that carabid communities would respond differently to 18 years of contrasted cropping practices in cereal-based rotations. We measured the effects of tillage (MP: moldboard plough; CP: chisel plough; NT: no-till) and previous crop sequence (cereal monoculture versus cereal-forage/cereal-oilseed rotation) on carabid beetle activity density, diversity, and community structure in corn (Zea mays Linnaeus, Poaceae) at La Pocatière, Québec, Canada. Carabid beetles were sampled monthly from May to September 2006, using pitfall traps. Although 19 carabid species were observed, assemblages were dominated by Harpalus rufipes (De Geer), particularly in the second half of the season. Multivariate analyses indicated a strong affinity of carabid species for the NT treatment throughout the season. Crop sequence and tillage had no effect on diversity (Shannon's H 0 r 1.3) and evenness of carabid assemblage, but species richness and activity density were greater in NT than in tilled systems. Peak activity density of dominant species occurred at different times during the season, generally in accordance with preferred breeding season. Many species had greater activity density in NT than in tilled treatments. Because of their granivorous feeding habit, carabid populations such as that of H. rufipes could be an important asset to NT, given the limited weed management options available for this system. Résumé-Les pratiques agricoles affectent les conditions biotiques et abiotiques qui vont définirl'habitat et les sources de nourriture pour les carabes (Coleoptera: Carabidae). Nous suggérons que 18 années de pratiques agricoles contrastées auront affecté les communautés de carabes dans des rotations à base de céréales. Nous avons mesuré les effets du travail du sol (CV: charrue à versoirs; CH: charrue scarificatrice; SD: semis direct) et de la succession des cultures (monoculture céréalière versus rotation céréale-fourrage/céréale-oléagineuses) sur l'activité densité, la diversité et la structure des communautés de carabes dans une culture de maïs (Zea mays Linnaeus; Poaceae) à La Pocatière, Québec, Canada. Les carabes ont été échantillonnés à partir de pièges fosses, de mai à septembre 2006. Bien que 19 espèces aient été observées pendant la saison, les communautés ont été dominées par Harpalus rufipes (De Geer), surtout en deuxième moitié de saison. Les analyses multivariées ont démontré une grande affinité des carabes pour le traitement en SD tout au cours de la saison. La succession des cultures et le travail du sol n'ont pas eu d'effet sur la diversité (indice de Shannon H 0 r 1.3) et sur l'équitabilité des communautés de carabes, mais le nombre d'espèces (richesse) et l'activité densité ont été plus élevés dans le SD que dans les parcelles labourées (CV, CH). Les pics d'activité densité des espèces se sont produits à différents moments au cours de la saison et, généralement,...

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