Thiessen Martens, J. R. and Entz, M. H. 2011. Integrating green manure and grazing systems: A review. Can. J. Plant Sci. 91: 811-824. Green manuring, also referred to as cover cropping, is an ancient practice that is gaining popularity, especially in ecologically integrated farming systems. Much green manure research in Canada has focused on legumes, where green manure plant material is incorporated into soil. This review focuses on the role of livestock in utilizing traditional and novel green manure crops adapted to the Canadian prairies. Legume and non-legume green manure plant species are discussed in terms of suitability to grazing management by different livestock species. Integrating grazing livestock into green manure systems affects nutrient cycling and potential nitrogen (N) loss pathways. However, losses may not be substantially different from other production systems, especially when loss mitigation practices are employed. Grazing green manures may also affect soil biological and physical properties. We conclude that grazing green manures may provide economic as well as biological advantages over the traditional approach of soil incorporation. For example, a green manure biomass yield of 5000 kg ha^-1 is sufficient to produce 175 kg ha^-1 of animal live weight gain, providing a gross revenue of $385 to $770 ha^-1 at April 2011 prices, while returning at least 75% of N and other nutrients to the field. Barriers to farmer adoption of grazed green manure systems include a lack of livestock management knowledge and infrastructure.

Tahir, M., Lindeboom, N., Båga, M., Vandenberg, A. and Chibbar, R. N. 2011. Composition and correlation between major seed constituents in selected lentil (Lens culinarisMedik.) genotypes. Can. J. Plant Sci. 91: 825-835. Development of lentil cultivars with increased seed amylose, protein and reduced concentration of anti-nutritional constituents are desired from the perspectives of lentil utilization and human health. In selected lentil genotypes, we studied seed weight, seed coat weight and color, seed composition and the association between major quality traits. Significant (P ≤ 0.05) variation existed for all traits except seed coat weight. The starch and protein concentrations ranged from 39.4 to 45.3 g and from 23.8 to 29.3 g 100 g^-1 flour DM whereas the amylose concentration ranged from 29.8 to 34.0 g 100 g^-1 starch. Glucose, sucrose and raffinose family oligosaccharides (RFO) concentrations of lentil genotypes ranged from 0.04 to 0.08 g, from 0.7 to 2.4 g, and from 4.6 to 6.6 mmoles 100 g^-1 flour DM, respectively. Raffinose, stachyose and verbascose concentrations varied from 1.6 to 2.4 g, from 1.7 to 2.9 g, and from 1.2 to 1.9 g 100 g^-1 flour DM, respectively. A significant (P ≤ 0.05) positive correlation existed between 1000-seed weight and starch, 1000-seed weight and RFO and sucrose concentration. Similarly, a significant (P ≤ 0 .05) negative correlation was found between starch and protein concentration, 1000-seed weight and protein concentration, and 1000-seed weight and amylose concentration. The lack of a significant correlation between RFO and other quality traits indicates that selection for low RFO concentration may not affect other important quality traits in lentil seeds.

Cuthbert, R. D., Crow, G. and McVetty, P. B. E. 2011. Assessment of seed quality performance and heterosis for seed quality traits in hybrid high erucic acid rapeseed (HEAR). Can. J. Plant Sci. 91: 837-846. Hybrids are becoming the dominant cultivar type in Brassica napus L. to utilize the well-documented heterosis for seed yield in canola/rapeseed. While there are numerous reports of heterosis for agronomic traits in B. napus hybrids, there are few reports of heterosis for seed quality traits in this species. The objectives of this study were to determine if high parent or commercial heterosis for any seed quality traits occurs in high erucic acid rapeseed (HEAR) hybrids. Seed quality performance of 45 F₁B. napus HEAR hybrids, derived from crosses of 12 geographically and genetically distinct (based on known pedigrees) HEAR cultivars/lines, was assessed in the current study using seven HEAR cultivars/lines developed by the University of Manitoba (UM) and five proprietary European (EU) HEAR cultivars/lines. Replicated field trials to assess seed oil, protein, sum of oil and protein, glucosinolate, and erucic acid concentrations were conducted over six environments in Manitoba during 2004 and 2005. High parent heterosis and commercial heterosis for seed oil concentration up to 9% and up to 14%, respectively, was observed with hybrids displaying seed oil concentrations as high as 533 g kg^-1. Low parent heterosis for protein and glucosinolate concentrations was also observed. Erucic acid concentration displayed commercial heterosis. Many hybrids displayed near zero percent heterosis for any seed quality traits; however, overall seed quality was maintained or increased even in these hybrids. The results of this study indicate that development of HEAR hybrids can be an effective way to improve seed quality components, especially oil concentration, in this crop.

LaRade, S. E. and Bork, E. W. 2011. Short Communication: Aspen forest overstory relations to understory production. Can. J. Plant Sci. 91: 847-851. We examined the relationship between aspen cover and understory production across two topographic positions and two management systems within the Aspen Parkland of eastern Alberta. Understory biomass typically declined with increasing overstory, with greater yield losses on north-facing forests than bottomlands. Browse often compensated for herbage loss, and limited evidence of facilitative growth was observed.

DeEll, J. R. and Ehsani-Moghaddam, B. 2011. Timing of postharvest 1-methylcyclopropene treatment affects Bartlett pear quality after storage. Can. J. Plant Sci. 91: 853-858. This study investigated the effects of postharvest 1-methylcyclopropene (1-MCP) treatment timing on the ripening and physiological disorders of Bartlett pears during cold storage and subsequent shelf-life. Pears were held for 1, 3 or 7 d at 3°C after harvest and then treated with 0.3 µL L^-1 1-MCP for 24 h at 3°C. Fruit quality attributes were evaluated after 4 mo of cold storage at 0.5°C, plus 1 to 11 d at 22°C. All 1-MCP treatments reduced ethylene production, as well as delayed fruit softening and yellow color development. However, the most substantial benefit of 1-MCP observed was the marked reduction in disorders, especially senescent scald and internal breakdown. The results suggest that 1-MCP treatment 3 d after harvest provided the best balance of reduced disorder development during storage and the ability of Bartlett pears to soften adequately thereafter. Fruit treated with 1-MCP at 1 d after harvest did not soften as much as those treated 3 or 7 d after harvest, while treatment after 7 d provided less control of disorders than treatment after 1 or 3 d.

Chang, K. F., Hwang, S. F., Gossen, B. D., Strelkov, S. E., Turnbull, G. D. and Bing, D. J. 2011. Effect of seeding practices, temperature and seed treatments on fusarium seedling blight of narrow-leaved lupin. Can. J. Plant Sci. 91: 859-872. Narrow-leaved lupin (Lupinus angustifolius) has the potential to become an important pulse crop for the Canadian prairies because of its high protein content and adaptation to a short growing season. However, disease surveys conducted from 2003 to 2007 in Alberta revealed that the crop is vulnerable to seedling blight and root rot caused by Fusarium spp. In field trials, the incidence of seedling blight was reduced by the application of the seed treatment fungicides Apron Maxx RTA, Crown, and Vitaflo 280. Seeding in late May resulted in reduced seedling emergence compared with early or mid-May in some cases, but the results were not consistent. Yield was reduced in the late-sown crop. Seedling emergence was often higher from seed sown at a 2- to 5-cm depth compared with a 7- to 10-cm depth. Yield was lower at seeding rates of 150 seeds m^-2 compared with 300 seeds m^-2. Under controlled conditions, emergence was greatest in inoculated soils at 25/15°C (day/night). Optimum shoot growth occurred at this temperature and plants were stunted at both higher and lower temperatures. Root growth was greatest at 15/5°C in non-inoculated soils and declined with increasing temperature; root growth was lower, but less variable, among the temperatures in inoculated soils. Root rot severity rose and seed emergence declined with increasing concentration of Fusarium avenaceum inoculum. To successfully grow lupin crops, soils with low Fusarium concentrations must be chosen and the crop should be planted in areas where high temperatures are not common.

Bing, D., Gan, Y. and Warkentin, T. 2011. Yields in mixtures of resistant and susceptible field pea cultivars infested with powdery mildew - defining thresholds for a possible strategy for preserving resistance. Can. J. Plant Sci. 91: 873-880. Powdery mildew (caused by Erysiphe pisi var. pisi DC.) resistance of field pea (Pisum sativum L.) cultivars is dominated by the single gene er1. Monoculture of the er1 gene may encourage pathogen evolution for more virulent race(s) and breakdown of the resistance. We promote the use of cultivar mixtures made up of resistant and susceptible cultivars to limit the pathogen evolution and to preserve the resistant gene in current cultivars. The objective of this study was to evaluate if such cultivar mixtures could cause significant yield losses and to identify the proper ratio of resistant and susceptible cultivars in a mixture. Three powdery mildew resistant cultivars were mixed with 0, 10, 20, or 30% of a susceptible cultivar, and gown in replicated trials at four locations over 2 yr in western Canada. The results show that severe powdery mildew infection caused yield reduction of 21-24%. The threshold of susceptible cultivars in a cultivar mixture depends on yield potential and performance of component cultivars, the severity of powdery mildew, and environments under which a cultivar mixture is grown. When disease severity was high and the resistant cultivar yielded well, 10 to 30% of the susceptible cultivar could be mixed with the resistant cultivars without significant yield reduction compared with the resistant cultivars in pure stand. The study suggests that such cultivar mixtures may be used in field pea production by providing more substrate to the pathogen so that the breakdown of resistant gene er1 may be delayed.

Soltani, N., Nurse, R. E., Shropshire, C. and Sikkema, P. H. 2011. Weed management in cranberry bean with linuron. Can. J. Plant Sci. 91: 881-888. Field studies were conducted at the Huron Research Station near Exeter, Ontario, in 2006 to 2009 to determine if the sequential application of trifluralin plus imazethapyr applied preplant incorporated (PPI) followed by linuron applied pre-emergence (PRE) at various doses can be used as an effective weed management strategy in cranberry bean production. There was minimal crop injury (6% or less) with various herbicides evaluated at 1 and 4 wk after emergence (WAE). Trifluralin plus imazethapyr applied PPI provided 97 to 100% control of common lambsquarters, 100% control of redroot pigweed, 99 to 100% control of wild mustard, 93 to 100% control of common ragweed, and 97 to 100% control of green foxtail. Linuron applied PRE provided 11 to 100% control of common lambsquarters, 90 to 100% control of redroot pigweed, 78 to 100% control of wild mustard, 71 to 100% control of common ragweed, and 20 to 100% control of green foxtail. The sequential application of trifluralin plus imazethapyr applied PPI followed by linuron applied PRE at various doses provided 100% control of common lambsquarters, 100% control of redroot pigweed, 100% control of wild mustard, 96 to 100% control of common ragweed, and 97 to 100% control of green foxtail. Weed density and shoot dry weight correlated well with the level of weed control. All of the herbicide treatments evaluated increased cranberry bean yield compared with the weedy control. Based on these results the sequential application of imazethapyr plus trifluralin applied PPI followed by linuron applied PRE at 1000 and 2500 g a.i. ha^-1 provides a safe and efficacious weed management strategy in cranberry bean production.

Blackshaw, R. E., Johnson, E. N., Gan, Y., May, W. E., McAndrew, D. W., Barthet, V., McDonald, T. and Wispinski, D. 2011. Alternative oilseed crops for biodiesel feedstock on the Canadian prairies. Can. J. Plant Sci. 91: 889-896. Increased demand for biodiesel feedstock has encouraged greater napus canola (Brassica napus L.) production, but there may be a need for greater production of other oilseed crops for this purpose. A multi-site field study was conducted to determine the oil yield potential of various crops relative to that of napus canola in the semi-arid, short-season environment of the Canadian prairies. Oilseed crops evaluated included rapa canola (Brassica rapa L.), juncea canola (Brassica juncea L.), Ethiopian mustard (Brassica carinata L.), oriental mustard (Brassica juncea L.), yellow mustard (Sinapis alba L.), camelina (Camelina sativa L.), flax (Linum usitatissimum L.), and soybean [Glycine max (L.) Max.]. Crop emergence and growth were generally good for all crops, but soybean did not fully mature at some locations. The number of site-years (out of a total of 9) that crops attained similar or greater yields compared to napus canola were camelina (6), oriental mustard (5), juncea canola (3), flax (3), soybean (3), rapa canola (2), yellow mustard (2), and Ethiopian mustard (1). The ranking of seed oil concentration was napus canola=rapa canola= juncea canola=flax>camelina=oriental mustard>Ethiopian mustard>yellow mustard>soybean. Considering yield and oil concentration, the alternative oilseed crops exhibiting the most potential for biodiesel feedstock were camelina, flax, rapa canola and oriental mustard. Oils of all crops were easily converted to biodiesel and quality analyses indicated that all crops would be suitable for biodiesel feedstock with the addition of antioxidants that are routinely utilized in biodiesel fuels.

Lu, Y., Jin, B., Wang, L., Wang, Y., Wang, D., Jiang, X.-X. and Chen, P. 2011. Adaptation of male reproductive structures to wind pollination in gymnosperms: Cones and pollen grains. Can. J. Plant Sci. 91: 897-906. Wind pollination (anemophily) in gymnosperms is thought to be an ancestral state. Previous studies considered wind pollination to be a largely random phenomenon, but recent evidence suggests that wind-pollinated species have evolved different complex reproductive adaptations for controlling and maximizing the success of wind pollination. However, compared with angiosperms, wind pollination in gymnosperms is poorly understood. We investigated the male reproductive structures of 13 representative gymnosperm species using a scanning electron microscope and digital camera, and analyzed how the morphological characteristics of male cones and pollen facilitate pollination. These characteristics showed a surprising variation between different gymnosperm species in improving pollination success. For example, the relationship between the position of the male cone and the surrounding vegetative structures is adjusted to optimize pollen release. The pollen grains have sacs and papilla and exhibit particular shapes after release from microsporangia, including boat-like, saccate, papilla-like and spheroid shapes, which facilitate pollen dispersal in the air. Taken together, our results suggest that the extensive diversity of male reproductive structures within gymnosperms represents an evolutionary response to long-term selection and results in solutions to the physical restraints of anemophily.

Braun, L. C., Gillman, J. H., Hoover, E. E. and Russelle, M. P. 2011. Nitrogen fertilization for young established hybrid hazelnuts in the Upper Midwest of the USA. Can. J. Plant Sci. 91: 907-918. Hybrids of Corylus avellana, C. americana and C. cornuta are proposed as a new crop for the Upper Midwest. Anecdotal information from midwestern growers suggests that these hybrid hazelnuts have high N requirements, but this has not been confirmed in replicated trials. Current nitrogen (N) recommendations for hazelnut production are based on research from the Pacific Northwest and may not be applicable to these hybrids in the Upper Midwest due to differing soils, climate, genetics, and growing systems. Three years of N rate trials on four plantings, that were 3 to 6 yr old at the start, showed that N responses of hybrid hazelnuts fit patterns for other woody crops: no N responses were found on soils with high organic matter, nor on soils with suspected P or K deficiencies. Where N responses were observed, they suggested that the N requirements of hybrid hazelnuts in the Upper Midwest are relatively low compared with those of European hazelnuts in the Pacific Northwest. Leaf N concentrations were within the expected ranges established for European hazelnuts in Oregon, suggesting that Oregon's standards may be applied to hybrid hazelnuts, except that 2.2% leaf N should be considered adequate, rather than a threshold to sufficiency.

DeLong, J. M., Hodges, D. M., Prange, R. K., Forney, C. F., Toivenon, P. M. A., Bishop, M. C., Elliot, M. L. and Jordan, M. A. 2011. The unique fatty acid and antioxidant composition of ostrich fern (Matteuccia struthiopteris) fiddleheads. Can. J. Plant Sci. 91: 919-930. The purpose of this study was to investigate the health-promoting composition of ostrich fern (Matteuccia struthiopteris) fiddlehead tissue by focussing on its fatty acid and antioxidant content and antioxidant activity. The curled crosiers (fiddleheads) were harvested following emergence and before 10 cm growth from eight or nine sites in eastern Canada during 2008 and 2009. The crosiers were then refrigerated or kept on ice until cleaned, subsequently frozen in liquid nitrogen, and then stored at -85°C. All tissue samples (except those used for ascorbate analysis) were freeze-dried, ground in a ball mill and stored at -80°C until analyzed. The current study showed that fiddlehead tissue had an unusual fatty acid composition including γ-linolenic, dihomo-γ-linolenic, arachidonic and eicosapentanoeic acids. The concentration of the antioxidant compounds ascorbic acid [3.0 µmol g^-1 dry weight (DW)], a- and γ-tocopherol (314 and 80.8 µg g^-1 DW, respectively) and a- and ß-carotene (43.8 and 122 µg g^-1 DW, respectively) and the xanthophyll pigments violaxanthin (225 µg g^-1 DW), zeaxanthin (127 µg g^-1 DW) and lutein (238 µg g^-1 DW), ranged from high to very high for green plant tissue. The phenolic compound content (51.6 mg gallic acid equiv. g^-1 DW) was also high compared with other fruits and vegetables and was likely responsible for the elevated antioxidant activity (1529 µmol trolox equiv. g^-1 DW; oxygen radical absorbing capacity assay) values recorded. Site differences were apparent for several of these measurements. Ostrich fern fiddlehead tissue appears to be a rich and unique source of antioxidant compounds, xanthophyll pigments and essential fatty acids.

Badu-Apraku, B. and Akinwale, R. O. 2011. Identification of early-maturing maize inbred lines based on multiple traits under drought and low N environments for hybrid development and population improvement. Can. J. Plant Sci. 91: 931-942. Drought and low nitrogen stresses are major limiting factors to maize (Zea mays L.) production and productivity in West and Central Africa. Studies were conducted from 2007 to 2009 at three locations in Nigeria under induced drought stress and low nitrogen conditions. The objective was to identify superior inbred lines for use as parents for hybrid production and for introgression into maize breeding populations. The inbreds TZEI 17, TZEI 13, TZEI 23, TZEI 2, TZEI 3, TZEI 22, TZEI 7, TZEI 11, and TZEI 8 were identified as the most promising parents under drought stress. Under low N, TZEI 7, TZEI 11, TZEI 2, TZEI 4, TZEI 10, TZEI 8, and TZEI 22 were selected. TZEI 11, TZEI 2, TZEI 8, and TZEI 22 had combined tolerance to drought stress and low N and could be used as germplasm sources for introgression of tolerance genes as well as for the development of drought and/or low-N-tolerant hybrids. Under drought stress, TZEI 17, TZEI 3, TZEI 23, and TZEI 13 were the closest to the ideal genotype, while TZEI 7, TZEI 2, and TZEI 11 were the closest under low-N conditions.

Légère, A. Stevenson, F. C. and Vanasse, A. 2011. Short Communication:A corn test crop confirms beneficial effects of crop rotation in three tillage systems. Can J. Plant Sci. 91: 943-946. Glyphosate-tolerant corn was planted with minimal fertilization in an 18-yr-old tillage and crop rotation experiment. Silage yields were 24% greater following a cereal-oilseed rotation than a cereal monoculture, regardless of tillage, and in spite of greater weed biomass in no-till. The diversified crop rotation proved beneficial, even in mature conservation tillage systems.

Warkentin, T., Vandenberg, A., Tar'an, B., Banniza, S., Bett, K., Barlow, B., Ife, S., Horner, J., de Silva, D., Thompson, M., Parada, M., Wagenhoffer, S. and Prado, T. 2011. CDC Hornet yellow field pea. Can. J. Plant Sci. 91: 947-949. CDC Hornet, a yellow cotyledon field pea (Pisum sativum L.) cultivar, was released in 2010 by the Crop Development Centre, University of Saskatchewan for distribution to Select seed growers in Saskatchewan and Alberta through the Variety Release Committee of the Saskatchewan Pulse Growers. CDC Hornet has good lodging resistance, medium-sized, round seeds, and good yielding ability. CDC Hornet is adapted to the field pea growing regions of western Canada.