Pan, X., Caldwell, C. D., Falk, K. C. and Lada, R. 2012. The effect of cultivar, seeding rate and applied nitrogen on Brassica carinata seed yield and quality in contrasting environments. Can. J. Plant Sci. 92: 961–971. The unremitting growth of oilseed demand makes it necessary to explore alternative oilseed crops to meet this requirement. This study evaluated the effects of genotype, seeding rate and nitrogen (N) supply on the seed yield and quality of oilseed Brassica carinata A. Braun in three contrasting environments (Truro, NS, Harrington, PE and Saskatoon, SK). Useful genetic variation in agronomic and seed quality characteristics was found among these 10 B. carinata genotypes and genotype selection requires location specific recommendation. Line 050488EM had consistently good yield in both Nova Scotia and Prince Edward Island, while line 070768EM displayed better yield stability across 2 yr in Saskatchewan. Because of the high degree of compensatory ability to low plant population, maximum seed yield of B. carinata can be achieved over the range from 34 to 114 plants m−2. No significant difference in oil and protein content of seed due to seeding rates was observed. The linear increase in seed and oil yield with increased N rate up to 150 kg ha−1 indicates that B. carinata is highly responsive to applied N. Increases in N supply resulted in a decrease in oil content and a corresponding increase in protein content in all experiments. In summary, the findings of this study provide convincing evidence of the agronomic adaptation of B. carinata to all three locations.

Camelina [Camelina sativa L. Crantz], an oilseed crop in the Brassicaceae family, was field tested at multiple locations in the Maritime Provinces of eastern Canada in 2012 to evaluate the effects of N and S on seed yield, protein content, protein yield, oil content, and fatty acid profile. The experiment was designed as a randomized complete block factorial design with six N rates (20, 40, 80, 120, 160, and 200 kg ha -1 N), two S rates (0 and 25 kg ha -1 S) and two lines of camelina (CDI005 and CDI007). The application of N increased the seed yield, protein content, protein yield, and percentage of polyunsaturated fatty acids (PUFA); however, N rate was negatively correlated with oil content and resulted in a reduction of monounsaturated fatty acids (MUFA). The optimum N rate for yield ranged from 120 to 160 kg ha -1 N. Sulfur affected yield, protein content, protein yield, oil content, percentage of MUFA, and percentage of PUFA only when the N level was sufficient.

L. 2008. The effect of cultivar and applied nitrogen on the performance of Camelina sativa L. in the Maritime Provinces of Canada. Can. J. Plant Sci. 88: 111Á119. Worldwide, oilseed demand is steadily expanding. This study assessed the novel oilseed crop Camelina sativa L. in the Maritime Provinces of Canada. Evaluations of cultivar and applied N were performed at Truro, NS, Harrington, PEI, and Hartland, NB, in 2005 and. The results show that the selection of cultivar is an important determinant for the potential success or failure of C. sativa production. Differences in plant stand, plant height, seed yield, oil content and fatty acid profile were found among the cultivars. The cultivar Calena provided the most consistent performance in terms of plant establishment, yield and oil content across all year-sites. Plant height, seed yield, oil content, total plant N and seed protein all responded to applied N rate. Applied N increased the seed yield of C. sativa, but the increase was not significant when the application rates were over 60 kg N ha(1 in NS or 80 kg N ha (1 in PEI. Plant height, total N content in plant tissue and seed protein content increased with increased N application, while oil content decreased. With the exception of erucic acid, all the main fatty acids in C. sativa oil responded to applied N levels or the interaction of N levels and year. Regression analysis showed that the contents of oleic acid and eicosenoic acid decreased with increased N application. The response of linolenic acid to N application was not consistent at each year-site. Results of this study provide convincing evidence of the agronomic suitability of C. sativa to the Maritime Provinces of Canada. Les re´sultats indiquent que le choix du cultivar joue un grand roˆle dans la re´ussite ou l'e´chec e´ventuels de la production de C. sativa. La densite´du peuplement, le rendement grainier, la teneur en huile et la composition en acides gras varient avec le cultivar. La varie´te´Calena est celle qui donne la performance la plus stable pour ce qui est de l'implantation, du rendement et de la teneur en huile pour l'ensemble des anne´es-sites. La hauteur du plant, le rendement grainier, la teneur en huile, la concentration totale de N dans la plante et celle de prote´ines dans la graine re´agissent tous a`la quantite´de N applique´e. L'amendement accroıˆt le rendement grainier de C. sativa, mais la hausse n'est pas significative aux taux supe´rieurs a`60 kg de N par hectare en N.-É . ou a`80 kg de N par hectare a`l'Iˆ.-P.-É . L'application d'une plus grande quantite´de N rehausse la hauteur du plant, la teneur totale de N dans les tissus et la concentration de prote´ines dans la graine mais on note une diminution de la teneur en huile. Outre l'acide e´rucique, tous les principaux acides gras de l'huile de C. sativa re´agissent a`l'application d'une quantite´supe´rieure de N. La re´action de l'acide linole´nique a`l'application de N est pas uniforme d'une anne´e-site a`l'autre. Les re´sultats de l'e´tude donnent des preuves convai...

Post-harvest needle abscission is a major challenge for Christmas tree and greenery industries. It was hypothesized that ethylene triggers abscission in balsam fir. Three experiments were conducted to test this hypothesis. In experiment 1, 70 balsam fir branches were collected, placed in water, and ethylene evolution was observed over time. In experiment 2, a 2 9 5 factorial experiment was designed to determine the effect of exogenous ethylene and an ethylene receptor blocker, 1-methylcyclopropene (1-MCP), on needle abscission. In experiment 3, a 2 9 6 factorial experiment was designed to determine the effect of exogenous ethylene and an ethylene inhibitor, aminoethoxyvinylglycine (AVG), on needle abscission. It was found that ethylene evolution was the highest 1-2 days prior to needle abscission, which was consistent in untreated branches and branches exposed to exogenous ethylene. Exposure to exogenous ethylene significantly decreased needle retention by 63%. When ethylene receptors were blocked by 1-MCP, needle retention increased by 147% despite the presence of ethylene and increased by 73% in the absence of ethylene when compared to the respective controls. When endogenous ethylene synthesis was inhibited by AVG, there was no improvement in needle retention in the presence of ethylene, but there was a 113% increase in needle retention in the absence of exogenous ethylene. Ethylene is strongly implicated as the signal triggering abscission in rootdetached balsam fir.

L. 2008. The effect of seeding rate, seeding date and seeder type on the performance of Camelina sativa L. in the Maritime Provinces of Canada. Can. J. Plant Sci. 88: 501Á 508. The hypothesis of this study was that spring camelina (Camelina sativa L.) could be grown as a high-value crop under the moist, cool conditions of the Maritime Provinces in Canada and seeding date, seeding rate, and type of seeder will modify productivity and oil composition. The objectives were (1) to determine the optimum seeding date and seeding rate for camelina production in the Maritimes; and (2) to evaluate the effect of seeder type (seed drill and forage seeder) on camelina establishment and seed yield. A seeding date and rate experiment and a seeder type and seeding rate experiment were conducted in 2005 and 2006 in Nova Scotia and Prince Edwards Island. Seeding date did not affect camelina emergence, plant height, seed yield and oil content. The earlier seeding date increased the concentration of stearic acid in the oil compared with the later seeding date. Seed yield of camelina was not affected by seeding rate in the seeder type by rate trial but higher yields were observed up to 600 seeds m Á2 in the seeding date by rate trial. The weak yield response to seeding rate could be explained by the high yield compensation ability of camelina through branching. It was suggested that seeding rates in the range of 400 to 600 seeds m Á2 would likely be best for camelina grown in the Maritime region. The forage seeder provided a better crop stand compared with the seed drill, although both seeders provided satisfactory crop establishment. Camelina has the potential to be produced successfully in the Maritime Provinces due to its adaptability to seeder type, low seeding rate requirements, and a wide window for seeding date. J. Plant Sci. 88: 501Á508. L'hypothe`se a`la base de cette e´tude est que la came´line faux-lin (Camelina sativa L.) pourrait devenir une culture lucrative dans le climat frais et humide caracte´ristique aux provinces Maritimes du Canada. Les auteurs postulent aussi que la date d'ensemencement, la densite´des semis et le type de semoir modifieront le rendement de la culture et la composition de l'huile. Les objectifs e´taient les suivants : (1) de´terminer la date d'ensemencement et la densite´des semis optimales pour la culture de la came´line dans les Maritimes et (2) e´valuer l'incidence du semoir (a`grains ou a`cultures fourrage`res) sur l'e´tablissement de la culture et son rendement grainier. À cette fin, les auteurs ont entrepris une expe´rience sur la date d'ensemencement et la densite´des semis ainsi qu'une seconde sur le type de semoir et la densited es semis en 2005 et 2006, en Nouvelle-É cosse et a`l'Iˆle-du-Prince-É douard. La date d'ensemencement n'a aucune incidence sur la leve´e de la came´line, la hauteur du plant, le rendement grainier ni la teneur en huile. Des semis plus pre´coces augmentent la concentration d'acide ste´arique dans l'huile, comparativement aux semis plus tardifs. Le rendement grai...

Response to irradiance of leaf net photosynthetic rates (P N ) of four carrot cultivars: Cascade, Caro Choice (CC), Oranza, and Red Core Chantenay (RCC) were examined in a controlled environment. Gas exchange measurements were conducted at photosynthetic active radiation (PAR) from 100 to 1 000 µmol m -2 s -1 at 20 o C and 350 µmol(CO 2 ) mol -1 (air). The values of P N were fitted to a rectangular hyperbolic nonlinear regression model. P N for all cultivars increased similarly with increasing PAR but Cascade and Oranza generally had higher P N than CC. None of the cultivars reached saturation at 1 000 µmol m -2 s -1 . The predicted P N at saturation (P Nmax ) for Cascade, CC, Oranza, and RCC were 19. 78, 16.40, 19.79, and 18.11 µmol(CO 2 ) m -2 s -1 , respectively. The compensation irradiance (I c ) occurred at 54 µmol m -2 s -1 for Cascade, 36 µmol m -2 s -1 for CC, 45 µmol m -2 s -1 for Oranza, and 25 µmol m -2 s -1 for RCC. The quantum yield among the cultivars ranged between 0.057-0.033 mol(CO 2 ) mol -1 (PAR) and did not differ. Dark respiration varied from 2.66 µmol m -2 s -1 for Cascade to 0.85 µmol m -2 s -1 for RCC. As P N increased with PAR, intercellular CO 2 decreased in a non-linear manner. Increasing PAR increased stomatal conductance and transpiration rate to a peak between 600 and 800 µmol m -2 s -1 followed by a steep decline resulting in sharp increases in water use efficiency.

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