Hassan, H. M., Jiang, Z.-H., Syed, T. A. and Qin, W. 2012. Review: Northern Ontario medicinal plants. Can. J. Plant Sci. 92: 815-828. The majority of scholarly investigations conducted in the 20th century have provided the incentive for establishing plants as sources of diverse phytochemicals. With infectious and cancerous diseases causing millions of mortalities worldwide, and the advent of resistant strains, the discovery of new antimicrobial and anticancer agents is crucial. Hence, included in this review is a novel list of 48 northern Ontario medicinal plants that may be sources of antifungal, antibacterial and/or anticancer phytochemicals. A total of two ferns and allied plants, two sedges and grasses, six trees, four shrubs, one vine and 33 herbs were identified. These plants were accumulated through interviews with native Elders and a survey of ethnobotanical literature on northern Canadian species of medicinal plants. We also present a critical review of their potential constituents, medicinal properties, and analysis of four promising plants (skullcaps, devil's club, St. John's wort and evergreens). Skullcaps and St. John's wort are model plants with documented anticancer, antibacterial and antifungal bioactivities. However, a considerable gap in ethnopharmacological data was found for species of skullcaps (Scutellaria galericulata, S. parvula and S. lateriflora) and St. John's wort (Hypericum mutilum, H. majus, H. canadense) growing in northern Ontario. These findings provide promising incentives in the ethnopharmacological community for medicinal research in this region.

Turner, F. A., Jordan, K. S. and Van Acker, R. C. 2012. Review: The recruitment biology and ecology of large and small crabgrass in turfgrass: Implications for management in the context of a cosmetic pesticide ban. Can. J. Plant Sci. 92: 829-845. Large and small crabgrass (Digitaria sanguinalis and Digitaria ischaemum, respectively) are problem weeds within turfgrass. As seedling recruitment shapes the demography of annual weeds, it is important to assess the recruitment biology and ecology of crabgrass species to determine how these aspects may be impacted by various management techniques. This, in addition to an assessment of large and small crabgrass' response to cultural management techniques in turfgrass, is the objective of this review. Turfgrass management either directly or indirectly affects the crabgrass recruitment microclimate by impacting the soil, topography, resources or plant cover, which in turn affects the degree and timing of crabgrass recruitment. Due to the increasing number and scale of cosmetic use pesticide bans in Canada this topic is particularly relevant. Crabgrass experiences a dormancy period of several weeks prior to being able to germinate. Microsite conditions of temperature and moisture have the greatest influence on dormancy breaking and germination; however, other factors such as light have shown some effect on recruitment. There is also evidence that factors such as seed scarification or treatment with nitrogenous compounds can increase recruitment. In turfgrass, common cultural practices, such as mowing, irrigation, and fertilization, can affect the recruitment of crabgrass. By pairing knowledge of the effects of microsite conditions on crabgrass recruitment with management that favours turfgrass vigour, better management practices to deter crabgrass infestation can be recommended. There are large gaps in research pertaining to the effects of cultural management techniques on crabgrass recruitment. Research to date has failed to make critical links between knowledge of these species' recruitment biology and ecology and how this is affected or can be applied through herbicide alternative management. This review recommends that regional assessments of crabgrass populations are necessary to determine the most appropriate management strategies. This type of research would have the potential to guide ideal application timings for existing and developing alternative herbicides as well as recommendations for the best cultural management practices to deter crabgrass infestation in turf.

Velasco, J. L., Rozas, H. S., Echeverría, H. E. and Barbieri, P. A. 2012. Optimizing fertilizer nitrogen use efficiency by intensively managed spring wheat in humid regions: Effect of split application. Can. J. Plant Sci. 92: 847-856. Efficient N fertilizer management is critical for the economical production of wheat and the long-term protection of the environment. Six experiments were conducted at three locations in the south-east of the province of Buenos Aires (SE), Argentina, during a 4-yr period, on Typic Argiudoll and Petrocalcic Paleudoll. The study was designed to evaluate the effects of splitting nitrogen (N) fertilizer on N use efficiency (NUE) in wheat (Triticum aestivum L.). Rates of 0 to 150 kg N ha^-1 were used, applied at tillering (Z24) or split between Z24 and flag leaf (Z39). The experimental design was a randomized complete block with three replications. Grain yield ranged from 3522 to 8185 kg ha^-1, according to N availability and application time. In the experiments without water stress (three out of six), average grain yield (across experiments) was 6669 and 6989 kg ha^-1 for full and split fertilization, respectively. In four out of six experiments, average N in above-ground biomass (NAB), N recovery fraction (NRF), and grain protein content (GPC) for split N application were greater than for full N at Z24 (NAB, 176 and 157 kg N ha^-1; NRF, 66 and 51%; GPC, 100 and 92 g kg^-1, for split and full N application, respectively). In years without water stress, splitting N between Z24 and Z39 is an appropriate strategy to improve NRF, reducing N losses, and minimizing the environmental impact of fertilization.

Wang, H.-W., Hu, H.-X., Song, T.-M. and Chen, S.-J. 2012. Seed traits evaluation from long-term selection of kernel oil concentration in a high-oil maize population KYHO. Can. J. Plant Sci. 92: 857-866. A high-oil maize population, KYHO, was developed over 10 generations by selective breeding for increased kernel oil content (KOC). The objectives of this study were to evaluate kernel oil selection effects, and measure the trait changes and genetic variance in the embryo and endosperm. Oil, protein, and starch content in the embryo and endosperm were estimated by near-infrared reflectance spectroscopy (NIRS). Mass and volume of embryo and endosperm were measured. Selective breeding increased embryo oil content (EMOC) and endosperm oil content (ENOC), especially EMOC, which changed from 315.62 g kg^-1 C0 to 592.54 g kg^-1 C10, resulting in an increase in total embryo and endosperm oil content (EEOC) from 43.32 g kg^-1 C0 to 139.95 g kg^-1 C10. With selection for increase in EEOC, embryo protein content (EMPC) decreased slightly; however, endosperm protein content (ENPC) and total protein content (EEPC) increased significantly. Embryo and endosperm starch content (EMSC and ENSC) and total starch content (EESC) all decreased substantially with selection. One hundred embryo mass (EMM) was not notably changed with selection, but 100 embryo volume (EMV) increased significantly. Mass and volume of endosperm (ENM and ENV) and total mass and volume of embryo and endosperm (EEM and EEV) all decreased significantly with selection, possibly due to markedly decreased starch content. Linear regression analysis indicated with each 1 g kg^-1 EEOC increase, EMOC, ENOC, ENPC, EEPC, EMM, and EMV increased 2.74 g kg^-1, 0.16 g kg^-1, 0.38 g kg^-1, 0.36 g kg^-1, 0.06 g, and 0.20 mL, respectively, and EMPC, EMSC, ENSC, EESC, EEM, ENM, EEV, and ENV decreased 0.04 g kg^-1, 1.48 g kg^-1, 0.60 g kg^-1, 1.09 g kg^-1, 1.26 g, 1.32 g, 0.97 g, and 1.17 mL, rspectively.

Meehan, M. A., DeKeyser, E. S., Sedivec, K. K. and Norland, J. E. 2012. Nutritional composition of Sprengel's sedge (Carex sprengelii). Can. J. Plant Sci. 92: 867-871. Sprengel's sedge (Carex sprengelii) has been documented as a primary graminoid species in riparian woodlands and forested areas of the northern Plains. Currently, there is no documentation of the nutrient content of Sprengel's sedge. The objective of this study was to determine the nutritional value of Sprengel's sedge of riparian woodlands in eastern North Dakota. Plants were clipped to 2.5 cm from the soil surface at 2-wk intervals during the growing seasons of 2009 and 2010. Multiple whole-plant samples were collected from five randomly selected sites at two different locations during each collection period. Plant tissue was analyzed for crude protein (CP), acid detergent fiber, neutral detergent fiber, in vitro organic matter digestibility (IVOMD), calcium, and phosphorus. The CP concentrations declined from over 20% in May to under 10% in October. Sprengel's sedge, based on IVOMD, met energy requirements for a 550 kg lactating cow early in the growing season; however, as the growing season progressed it was unable to meet energy requirements. Irrespective of year, Sprengel's sedge maintains a high CP level throughout a typical grazing season; however, digestible energy becomes deficient. Grazing strategies that promote spring and early summer grazing or supplementation of a high-energy feed source to compensate for the decrease in energy are recommended.

Schmer, M. R., Xue, Q. and Hendrickson, J. R. 2012. Salinity effects on perennial, warm-season (C₄) grass germination adapted to the northern Great Plains. Can. J. Plant Sci. 92: 873-881. Limited information is available on the germination of perennial C₄ grasses adapted to the northern Great Plains under saline conditions. Big bluestem (Andropogen gerardii Vitman), indiangrass [Sorghastrum nutans (L.) Nash], prairie cordgrass (Spartina pectinata Link), and switchgrass (Panicum virgatum L.) seeds were evaluated under non-saline and saline conditions corresponding to electric conductivity (EC) values of 0, 4, 8, 12, 16, and 20 dS m^-1, respectively. Ten cultivars were evaluated to determine salinity tolerance differences among and within species. Seeds were monitored for 21 d and analyzed for final germination percentage (GP), germination rate index (GRI), corrected germination rate index (CGRI), and germination velocity (GV). Differences among species were observed for all indices tested (P<0.01). Indices showed within species variation for big bluestem, indiangrass, and switchgrass. Big bluestem had the highest germination rates under increased salinity levels while prairie cordgrass had the lowest germination rates under non-saline and saline conditions. Indiangrass showed higher seed germination than switchgrass under low EC levels (0 to 4 dS m^-1) but declined at a higher rate when EC levels exceeded 16 dS m^-1. Results from this study suggest grassland reestablishment from seed on variable saline soils will be dependent on both the species chosen and the specific cultivar used.

Morin, C., Bélanger, G., Tremblay, G. F., Bertrand, A., Castonguay, Y., Drapeau, R., Michaud, R., Berthiaume, R. and Allard, G. 2012. Short Communication: Diurnal variations of nonstructural carbohydrates and nutritive value in timothy. Can. J. Plant Sci. 92: 883-887. Nonstructural carbohydrate (NSC) concentration in timothy (Phleum pratense L.) increased during the day by 16 to 41 g kg^-1 DM ( 23 to 137%) in spring and summer growth cycles and reached a maximum value between 12.8 and 13.2 h after sunrise in an area with 15 to 16 h of day length. This increase in NSC concentration was generally accompanied by a decrease in concentrations of neutral detergent fiber (-2 to 6%), acid detergent fiber (-1 to 7%), and N (-6 to 11%).

Corriveau, J., Gaudreau, L., Caron, J., Jenni, S. and Gosselin, A. 2012. Testing irrigation, day/night foliar spraying, foliar calcium and growth inhibitor possible as cultural practices to reduce tipburn in lettuce. Can. J. Plant Sci. 92: 889-899. Most of the lettuce produced in Quebec, Canada, is grown in organic soils in the area south of Montreal. Regularly, producers experience tipburn damage to their crop, a physiological disorder associated with Ca deficiency along the margins of young actively growing leaves. Therefore, active research is ongoing to reduce damage associated with this disorder. Two greenhouse trials on Romaine lettuce (Lactuca sativa L. ‘Sunbelt’) were conducted to measure the effect of day and night foliar water spraying, irrigation, foliar application of prohexadione calcium (a growth inhibitor) and foliar application of Ca on lettuce growth and incidence of tipburn. None of the treatments had a significant effect on biomass, dry weight, leaf number or leaf area in lettuce. However, the results show that frequent foliar applications of Ca as low as 90 mg L^-1 Ca² resulted in a significant decreases in the number of leaves and percent leaf area with tipburn, and significant increases in Ca content in young leaves. Foliar water spraying, irrigation and foliar application of prohexadione calcium resulted in no significant differences in tipburn in greenhouse experiments. As greenhouse and field conditions may differ importantly, Ca application should be tested further at the field scale.

Stoffyn, O. M., Tsao, R., Liu, R. and Wolyn, D. J. 2012. The effects of environment and storage on rutin concentration in two asparagus cultivars grown in southern Ontario. Can. J. Plant Sci. 92: 901-912. Flavonoids have been shown to have many human health benefits due to their antioxidant activity. Concentration of rutin, the primary antioxidant in asparagus spears, can vary significantly with cultivar, location and season. Assessment of rutin in cultivars across locations throughout the harvest season in Southern Ontario, as well as in stored asparagus, is important for defining the potential benefits of consuming local asparagus. The objectives of this research were to determine the effects of cultivar, harvest time, location, spear diameter and part, and storage of fresh spears and freeze-dried flour on rutin concentration. Sampling date over the 6-wk harvest season and location did not significantly affect rutin concentration in either of the two cultivars tested. Rutin concentration was inversely related to air temperature before harvest and spear diameter, and for any given diameter, was highest in the tops of spears and decreased towards the bottom, in both cultivars. Soil temperatures before harvest were not correlated with rutin concentrations. Storage of fresh spears at 4°C, or freeze-dried flour at varying temperatures, did not affect concentration. The stability of rutin concentration throughout the harvest season, across locations and in stored products suggests predictable antioxidant levels in Ontario-grown asparagus.

Vink, J. P., Soltani, N., Robinson, D. E., Tardif, F. J., Lawton, M. B. and Sikkema, P. H. 2012. Glyphosate-resistant giant ragweed (Ambrosia trifidaL.) control with preplant herbicides in soybean [Glycine max(L.) Merr.]. Can. J. Plant Sci. 92: 913-922. Giant ragweed populations in southwestern Ontario have evolved resistance to glyphosate. Glyphosate-resistant (GR) giant ragweed interference in field crops can lead to significant yield losses. Eleven field trials [five with preplant (PP) burndown only and six with PP burndown plus residual herbicides] were conducted in 2010 and 2011 on Ontario farms with GR giant ragweed to evaluate the efficacy of various PP herbicides applied prior to soybean planting. Glyphosate applied at the recommended field dose failed to adequately control GR giant ragweed. The PP herbicides 2,4-D ester, cloransulam-methyl and saflufenacil applied alone and with glyphosate provided 97-99, 68-100 and 71-94% control, respectively and resulted in soybean yields equivalent to the weed-free check. Combinations of glyphosate plus cloransulam-methyl or linuron controlled GR giant ragweed 8 wk after application (WAA), 75-95 and 95-98%, respectively. Residual control with glyphosate plus linuron resulted in soybean yield equivalent to the weed-free check. Based on these results, GR giant ragweed can be controlled prior to soybean planting in southwestern Ontario.

Beckie, H. J. and Shirriff, S. 2012. Site-specific wild oat (Avena fatuaL.) management. Can. J. Plant Sci. 92: 923-931. Variation in soil properties, such as soil moisture, across a hummocky landscape may influence wild oat emergence and growth. To evaluate wild oat emergence, growth, and management according to landscape position, a study was conducted from 2006 to 2010 in a hummocky field in the semiarid Moist Mixed Grassland ecoregion of Saskatchewan. The hypothesis tested was that wild oat emergence and growth would be greater in lower than upper slope positions under normal or dry early growing season conditions. Three herbicide treatments were imposed on the same plots each year of a 2-yr canola (Brassica napus L.) - wheat (Triticum aestivum L.) sequence: (1) nontreated (weedy) control; (2) herbicide application to upper and lower slope positions (i.e., full or blanket application); and (3) herbicide application to lower slope position only. Slope position affected crop and weed densities before in-crop herbicide application in years with dry spring growing conditions. Site-specific wild oat herbicide application in hummocky fields in semiarid regions may be justified based on results of wild oat control averaged across slope position. In year 2 of the crop sequence (wheat), overall (i.e., lower and upper slope) wild oat control based on density, biomass, and dockage (i.e., seed return) was similar between site-specific and full herbicide treatment in 2 of 3 yr. Because economic thresholds have not been widely adopted by growers in managing wild oat, site-specific treatment in years when conditions warrant may be an appropriate compromise between no application and blanket herbicide application.

Van Acker, R. C. and Cici, S. Z. H. 2012. Short Communication: Timing of stinkweed and shepherd's-purserecruitment affects biological characteristics of progeny. Can. J. Plant Sci. 92: 933-936. The effect of recruitment timing (fall versus spring recruitment) on seed characteristics and performance of two common Canadian facultative winter annual weeds; stinkweed (Thlaspi arvense L.) and shepherd's-purse (Capsella bursa-pastoris L.) was investigated. Seed germination proportion was unaffected by maternal emergence timing but germination was faster for spring versus winter cohort seeds of stinkweed. Proportionally more seeds from winter (fall-recruited) cohorts were rendered non-viable by aging treatments, while for shepherd's purse, aging treatments broke dormancy instead of reducing viability and this was especially true for winter cohort seeds. For both weed species, spring cohort seeds produced earlier flowering plants with greater and lesser biomass allocation to reproductive tissues and roots, respectively. These results show the potential importance of germination timing and maternal effects on weed populations and demonstrate additional complexity in the nature of facultative winter annual weeds, in particular.

Zhang, Y., Feng, L., Wang, E., Wang, J. and Li, B. 2012. Evaluation of the APSIM-Wheat model in terms of different cultivars, management regimes and environmental conditions. Can. J. Plant Sci. 92: 937-949. Wheat is one of the most important crops in the world, and wheat models have been widely used to study yield responses to changes in management and climate. However, less information is available on how a wheat model performs in simulation of wheat response to changes in varieties, sowing dates and planting densities across space. This study presents an evaluation of the APSIM-Wheat model using data from field experiments consisting of three sowing dates, two and three crop varieties and three planting densities in a split-split plot design at three ecological sites from 2008 to 2010 in the North China Plain. The results show that the APSIM-Wheat model could capture a large part of the variation in phenology, biomass and yield for the same variety across sites. However, errors of simulation in phenology and yield were increased with delay in sowing date, with the average absolute root mean square errors of 2 d, 3 d, and 3-4 d in phenology, and the normalized root mean square error (RMSEn) of 7-12%, 11-16%, 16-22% in yield at early, medium, and late sowing dates, respectively. Simulation of yield achieved poor results with decreased planting density, with average RMSEn of 9-12%, 11-12%, and 16-19% at high, medium, and low density, respectively. Additionally, the simulation behaved in a complex manner, and the errors varied greatly with different combinations of sowing dates and planting densities. These alerted us that the model should be used cautiously to simulate growth and yield over a wide range of sowing dates and planting densities. Improved modeling of the responses of wheat growth to extreme temperatures during winter and spring periods, and to varying planting densities is needed for better future prediction. Other areas of model improvements are also discussed.

Ullah, H., Khalil, I. H., Durrishahwar, Iltafullah, Khalil, I. A., Qasim, M., Khan, S. M., Yan, J. and Ali, F. 2012. Selecting high yielding and stable mungbean [Vigna radiata(L.) Wilczek] genotypes using GGE biplot techniques. Can. J. Plant Sci. 92: 951-960. Multi-environment trials (MET) play a vital role in selecting genotypes for wider adoptability based on their superior performance across environments. The present study was carried out with the aim of selecting high-yielding and stable genotype(s). A set of 30 mungbean genotypes were evaluated in four environments comprising years (2007, 2008) and locations (Peshawar, Swat) in Pakistan. Combined analysis of variance was performed for seed yield to determine the effect of environment [consisting of year (Y), location (L), and L × Y interaction], genotypes and all possible interactions among these factors. Analysis of variance showed significant genotype × year (G × Y) and G × L interactions (P ≤ 0.01) exhibiting the influence of changes in environment (L and Y) on seed yield performance. The large yield variation due to environment (E), justified the selection of a genotype main effect genotype×environment (GGE) biplot as an appropriate method for analyzing MET data. GGE biplot arranged 30 genotypes in such a manner that they fell in four sectors based on their performance. Genotype'k' (NFM-11-3) performed well at PR07 and PR08, denoted as the first sector. In the second sector, mungbean genotype'y' (NFM-7-13) outclassed all other genotypes at ST07 and ST08. GGE biplot figured out the genotypes't' (NFM-14-5) and'e' (NFM-5-63-20) as the poor performing lines across location. GGE biplot identified ‘y’ (NFM-7-13) as the highest yielding genotype, followed by ‘k’ (NFM-11-3). Solely on yield performance, both of the genotypes were not statistically different however; the ranking made by GGE biplot was not only based on yield but on stability performance too. Similarly, Genotypes ‘Ad’ (NM-98) ‘m’ (NFM-12-6) ‘f’ (NFM-5-63-34) and ‘z’ (NFM-8-1) ranked 3rd, 4th, 5th and 6th as being stable and high-yielding across locations, respectively. Location ‘PR08’ was the most desirable environment as it lay closer to the “ideal” environment. While PR07, ST07 and ST08 were found undesirable regarding genotype differentiation as they were far away from the center of the concentric circle. The GGE biplot effectively identified the G × E interaction pattern of the data and explained which genotype performed extravagantly at which target environment.

Pan, X., Caldwell, C. D., Falk, K. C. and Lada, R. 2012. The effect of cultivar, seeding rate and applied nitrogen onBrassica carinataseed 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.

Tamburic-Ilincic, L., Smid, A. and Griffey, C. 2012. OAC Amber winter durum wheat. Can. J. Plant Sci. 92: 973-975. OAC Amber is the first winter durum wheat (Triticum turgidum subsp. durum L.) cultivar registered for Ontario, Canada. It is an awned wheat with amber colored kernels, high test weight, kernel weight, and protein level with good winter hardiness. OAC Amber has good resistance to leaf rust (Puccinia triticina) but is moderately susceptible to powdery mildew (Blumeria graminis) and leaf blotch (Septoria tritici), and susceptible to Fusarium head blight (FHB). OAC Amber is well adapted for the winter wheat growing areas of Ontario.

Khanizadeh, S., Granger, R., Dubé, C. and Groleau, Y. 2012. Javid Crab Apple. Can. J. Plant Sci. 92: 977-978. Javid is a winter-hardy, scab-resistant ornamental apple tree released by Agriculture and Agri-Food Canada (AAFC), Horticulture Research and Development Centre (HRDC). It is suitable for growing in Quebec and eastern and central Canada. The name ‘Javid’ is derived from the Persian ‘jawid’ meaning eternal, forever, continuous or permanent, due to its fruit persistency after ripening, and is named after the first author's son.