Germinability of dormant seeds or the capacity to germinate under particular conditions is sometimes enhanced by a diurnal alternating temperature regime relative to a constant temperature. Alternating temperature regimes vary in amplitude (difference between the minimum and maximum) and midpoint (average). The aim of this research was to test the effects of amplitude and midpoint regimes on germination of dormant leafy spurge seed from a Fargo, ND population in water and gibberellic acid (GA₃). The optimal regimes for germination in both water and GA₃ were 20:30 °C (16 h:8 h) and 20:35 °C (19 h:5 h), which provided amplitudes of 10 °C and 15 °C, respectively, with both conditions having a midpoint temperature of 23.3 °C. However, midpoint temperature of 22 °C to 27 °C were equally effective for germination under the 20:30 °C and 20:35 °C alternating temperature regimes. Additional alternating temperature regimes with amplitudes of 15 °C (15:30 °C and 10:25 °C), 20 °C (10:30 °C), and 25 °C (10:35 °C) generally displayed reduced germination in both water and GA₃, which is likely attributable to the low initial alternating temperature (≤15 °C) component of the regime relative to the higher initial temperature of 20 °C for the optimum regimes of 20:30 °C and 20:35 °C. Under the alternating temperature regimes tested, seeds germinated in GA₃ generally displayed higher germination (≥80%) compared with seeds in water (30%-50%).

Plant habitat, growth, fruit yield and occurrence of pollinators in cloudberry and lingonberry fields/bogs were monitored and analyzed at three locations in southern Labrador: Lanse'au Clair (51°41′ N, 57°08′ W), Red Bay (51°43′ N, 56°26′ W), and Cartwright (53°42′ N, 57°0′ W) over the two growing seasons, 2011 and 2012. The length of the growing seasons was 100-120 d (DFRA 2014) with 600-700 growing degree days (GDD) (AAFC 2014). The 2012 season was warmer than 2011. The plants recorded in belt transects belong to six families: Rosaceae, Ericaceae, Pottiaceae, Juncaeae, Equisetaceae, and Sphagnaceae. In the Ericaeae family, Vaccinium vitis-idaea, Arctostaphylos alpina, Empetrum nigrum, and Vaccinium angustifolium were found. In both seasons, the cloudberry was the first to bloom, followed by wild blueberry, lingonberry, and Labrador tea. The fruit yields of cloudberry and partridgeberry in southern Labrador were higher than those recorded in Finland, Norway, and in the USA. Pollinators were present in large numbers. Most of the specimens were from three orders: Hymenoptera, Diptera, and Lepidoptera. Temperature, precipitation, wind, and sunlight affected plant growth and the occurrence of pollinators. To our knowledge this is the most comprehensive study of plant growth, yield, and pollinators' activity in cloudberry/partridgeberry fields conducted in Southern Labrador, Canada.

Profitable malting barley (Hordeum vulgare L.) production systems are required to reverse the decline in area seeded to malting barley in western Canada. Systems that could increase the profitability of growing malting barley considered the previous crop, nitrogen (N) rate, and fungicide application. The net return (NR) and risk for these systems were computed from western Canada field data. Analysis of variance was used to evaluate the impact of systems on NR over 21 site-years of field data. Risk was evaluated with a stochastic simulation model. NR was higher and risk lower for malting barley when the preceding crop was field pea (Pisum sativum L.), when fungicide was applied at the flag leaf stage for leaf disease control, and when N was 50% of the recommended N rate. Therefore, malting barley should be grown on field pea stubble at a lower N rate, with fungicide applied when there are leaf diseases.

The effects of abscisic acid (ABA) form, concentration, and application timing on bud cold hardiness, phenology, and fruiting performance of Merlot grapevines (Vitis vinifera) were evaluated in a three-year field trial with site locations in British Columbia and Ontario, Canada, and in Washington and Idaho, United States. Solutions containing natural S-ABA (ABA_N) and a purported long-lived ABA analogue 8′-acetylene ABA (ABA_A) at differing concentrations were applied to the vine canopy at veraison or post-harvest. Postharvest foliar applications of ABA_N at concentrations greater than or equal to 5000 ppm tended to advance leaf abscission and increase autumn bud cold hardiness. Postharvest foliar applications of ABA_A at 1000 ppm tended to delay budbreak in the spring following application and increase spring bud cold hardiness. Fruit yield and basic composition were affected little by the ABA treatments. Bud hardiness was enhanced by ABA_N mostly in autumn and by ABA_A mostly in the spring, indicating that the suitability of ABA forms for reducing bud damage would depend on when injurious cold events are more likely.

The popularity of grain amaranth and quinoa is growing in Ontario, increasing the interest in their cultivation. Two experiments were conducted in southern Ontario in 2013 and 2014 to evaluate optimal planting date (every two weeks from early May to late July), row width (38 or 75 cm), and critical weed-free period (the component of the critical period of weed control that defines the number of days that the crop must remain weed-free to prevent yield loss) in each crop. Grain amaranth and quinoa both reached physiological maturity and produced yields when planting dates ranged from mid-May to late-June. When either crop was seeded in July, yields decreased by more than 50% and the crop did not always reach maturity before the first frost. While row width did not have an impact on yield, it is advisable to grow the crops in wider rows (75 cm) to facilitate weed control early in the growing season (up to 30 d after emergence (DAE)). The critical weed-free period was 24 and 16 DAE for grain amaranth and quinoa, respectively, after which yields were maintained at 95% of the weed-free control. Based on these data, both crops could easily be integrated into the normal cropping rotations found in southern Ontario.

AAC Vitality is a six-row spring feed barley (Hordeum vulgare L.) cultivar developed by the Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada. AAC Vitality had high grain yield, good resistance to lodging, and good resistance to straw break. It was late in heading and maturity. Its seed color was bright. AAC Vitality was moderately resistant to net blotch and spot blotch. AAC Vitality performs well in Ontario.

Turmeric, a vegetatively propagated crop, may have restricted variability from which to breed new cultivars. Understanding the genetic variability of a species is crucial for the progress of a genetic breeding program and requires characterization and evaluation of accessions. The objectives of this study were to determine extent of variability, relationships between different agro-morphological traits, and diversity among 25 different accessions of turmeric. The present experiment was conducted at the Vegetable Research Farm, Department of Horticulture, Sam Higginbottom Institute of Agriculture, Technology and Sciences, Allahabad, India during 2008–2009 and 2009–2010. Accessions were arranged in a randomized complete block design with three replications. Significant mean square of accessions for all the traits studied indicates the existence of sufficient genetic variability among the studied accessions. The rhizome yield exhibited highly significant and positive association with plant height, number of leaves plant^-1, number of tillers plant^-1, weight of rhizomes plant^-1, length of primary rhizome, and dry matter recovery. The highest positive direct effect on rhizome yield was exerted by plant height. Multivariate analysis techniques allowed an effective study of genetic divergence and the grouping of the 25 accessions into six clusters. The highest inter-cluster distance was observed between cluster II and IV, accessions from these clusters can be used as potential parents for future breeding programs.

Development of 2,4-D-resistant Brassica napus varieties is valuable for conservation tillage and post emergence control of broadleaf weeds. This research documents successful production and transfer of 2,4-D resistance from Raphanus raphanistrum (wild radish) into, Brassica napus via embryo rescue.

CO455 is a short season stiff stalk-type corn (Zea mays L.) inbred line with excellent combining ability as well as intermediate resistance to common smut, common rust, eyespot and fusarium stalk rot. Excellent hybrid yields and performance data were achieved when CO455 was combined with Iodent testers such as MBS8148.

A two-year (2010-2011) field experiment was undertaken to examine the effect of nitrogen (N) rate (0, 100, 150, and 200 kg N ha^-1) and N source (urea, calcium ammonium nitrate; ammonium sulphate) on canopy reflectance, chlorophyll pigments, photosynthesis, yield, grain quality, and N-use efficiency in corn. However, the physiological observations were made only in 2011. We found that stover biomass was unaffected by higher N rate beyond 150 kg N ha^-1 in both years. Higher N rates did not provide a yield advantage as compared to 150 kg N ha^-1 in 2010, but the highest grain yield was produced with 200 kg N ha^-1 in 2011. The higher grain yield by N application was attributed to a greater kernel size in both years. Corn stover [N] was found to increase with increasing N rates in both years. Kernel [N] only responded to the high N rate in 2010. There was no change in the kernel density as affected by N rate in both years. An increased N addition resulted in a decrease in both N-uptake efficiency and agronomic-N use efficiency in both years. There was an inconsistent effect of N source on yield and N use efficiency indices in the corn over two years.

Protein and starch are two major components in field peas. In this study, we investigated the starch morphologies, compositions, and thermal properties between high protein peas (approximately 30%) and other market types of field peas (yellow, green, maple, and marrowfat peas, with approximately 23% protein contents). For the shape and size, high protein peas had the compound starch granules that could be easily fragmented into small irregular and polygonal granules, whereas other pea types had oval or kidney-like starch granules with high percentage of large granule sizes. High protein peas had significantly lower starch contents (27.2%-34.2%) than other pea types (45.5%-47.4%). However, the amylose content (74.6%-89.2%) in high protein peas were significantly higher that of other pea types (50.1%-54.1%). Our differential scanning calorimeter (DSC) data showed that the onset temperature (T_o), peak temperature (T_p), and conclusion temperature (T_c) of starch gelatinization in high protein peas were significantly higher than those of other pea types, whereas the enthalpy change (▵H) of high protein peas was significantly lower than those of other pea types. The unique properties of high protein peas characterized in this study provided useful information to further improve pea quality.

Reed canarygrass (Phalaris arundinacea L.) is a potential biomass crop for energy production but little is known on its optimum management in the northern areas of North America. We determined the effect of three harvest dates (late July, early September, and mid-October) in a one-cut system and four N fertilization (0, 40, 80, and 160 kg N ha^-1) on crop biomass and silage characteristics of reed canarygrass seeded in 2007, and harvested and ensiled in 2008 and 2009 following spring N applications. Delaying harvest from late July to mid-October decreased crop biomass dry matter (DM) yield (-0.8 Mg DM ha^-1), in vitro true digestibility of DM (IVTD; -79 g kg^-1 DM), in vitro neutral detergent fiber (NDF) digestibility (NDFD; -126 g kg^-1 NDF), and K concentration (-7.4 g kg^-1 DM), while it increased soluble carbohydrate ( 14.7 g kg^-1 DM) and ash ( 8.5 g kg^-1 DM) concentrations. Increasing N fertilization from 0 to 160 kg N ha^-1 increased crop biomass DM yield ( 4.3 Mg DM ha^-1), crop biomass NDF ( 29 g kg^-1 DM) and ADF ( 32 g kg^-1 DM) concentrations, decreased IVTD (-65 g kg^-1 DM) and NDFD (-76 g kg^-1 NDF), and did not affect ash concentration. Silage pH and concentrations of lactate and NH₃-N indicated adequate fermentation irrespective of harvest date and N fertilization.

Seed oil content is a key seed quality trait determining the economic value of rapeseed (Brassica napus L.). However, it is a complex quantitative trait controlled by multiple genes. To this point, its genetic mechanism in rapeseed remains to be revealed. In the present study, we separately identified the quantitative trait loci (QTL) controlling seed oil content of B. napus using three generations of recombinant inbred line (RIL) populations (F_4:5, F_5:6, and F_6:7) derived from a cross of two contrasting parents (M201, a high-oil parent, and M202, a low-oil parent) in four trials. The results indicated that the additive effects may be the primary factors contributing to the variation in seed oil content in B. napus. A total of 15 QTL for seed oil content were mapped. Two of them, namely qOC-A9-3 and qOC-A10, were consistently detected across two and all four environments, respectively. Meanwhile, qOC-A10 showed a large effect on phenotypic variation in seed oil content. The stability and significance of qOC-A10 was also validated in the near isogenic lines (NILs-qOC-A10) developed from the RIL population (F_4:5) using marker-assisted selection. The qOC-A10 is of particular interest for further fine mapping and map-based cloning.

Plant 14-3-3 proteins (14-3-3s) are known to function in protein-protein interactions that mediate signal transduction pathways regulating many biological processes. The cDNA encoding putative 14-3-3 protein was isolated from pear (Pyrus pyrifolia) and designated Pp14-3-3b. Using the PCR amplification technique, the genomic clone corresponding to Pp14-3-3b was isolated and shown to contain six introns. Phylogenetic analysis clearly demonstrated that Pp14-3-3b was classified into the non-ε class of 14-3-3 superfamilies. Quantitative RT-PCR analysis indicated that the expression of the Pp14-3-3b gene was developmentally regulated in fruit. This study suggested that Pp14-3-3b might be involved in fruit ripening and the senescence of pear.

In estimation of genetic parameters in perennial tree species on the basis of analysis of variance (ANOVA), heterogeneity of years and genotype × environment interaction for data sets during the juvenility to maturity life period is ignored. Therefore, a linear mixed model based on restricted maximum likelihood (REML) approximation for modeling of covariance structure of longitudinal data can improve our ability to analyze repeated measures data. In the present research, a modeling of variance-covariance structure by mixed model based on the REML approach has been used for characteristics of 26 apricot genotypes recorded during three years. Fitting unstructured covariance (UN) models for all traits indicated a great heterogeneity of variances among repeated years and the trends of response variables in the genotypes (except for RWC) was due to imperfect correlation of subjects measured in different years. Based on the same structure, positive correlations were estimated among fruit set, potassium content, and yield of pistil in repetitive years, and most traits showed high heritability estimation. To our knowledge, this is the first report in plant that genotypic correlation and heritability and their standard errors are estimated in a repeated measures data over years using REML approximation.

Weed seeds present in harvested silage have to survive silage fermentation and rumen digestion before they are dispersed as a contaminant of manure. Therefore, producing crops that are ensiled could lower the seed dispersal of weed escapes. This study is aimed at evaluating the viability of seven weed species after storage in experimental mini-silos filled with corn or alfalfa. Nylon mesh bags, each containing one hundred seeds of a weed species, were inserted at random locations in mini-silos filled with silage corn or alfalfa and stored for one, three or six months. The experiment included five mini-silos per storage time as well as untreated seeds. Water imbibition by intact seeds was also evaluated to determine if it could be related with survival in silage. After three and six months of storage few seeds were viable in any treatment (<0.1% of all seeds tested). Differences between weed species and silage type were observable after one month of storage and could not be related to seed coat permeability as measured by water imbibition. Ensiling for three to six months, or more, could be used to kill harvested weed seeds. Further evaluations in commercial farm silos could be done to support results.

There is limited information on the effect of weed size at the time of application on glyphosate efficacy in Ontario. Eleven field trials were conducted over a 3 yr period (2010–2012) in Ontario to determine the biologically effective dose of glyphosate applied postemergence (POST) in corn at doses of 112.5–1350 g acid equivalent (a.e.) ha^-1 for the control of various grass and broadleaved weed species when the weeds were 10, 20 or 30 cm in height. The GR90 for redroot pigweed, common ragweed, common lamb's-quarters, barnyardgrass, and green foxtail were 353, 630, 621, 763, and <112.5 g a.e. ha^-1 when applied at 10 cm weed height, 235, 201, 906, 868, and 296 g a.e. ha^-1 when applied at 20 cm weed height, and 792, >1350, >1350, 912, and 675 g a.e. ha^-1 when applied at 30 cm weed height, respectively. Corn yields were maximized when glyphosate was applied to weeds that were up to 10 cm in height, but was reduced with later glyphosate application timings. The results of this study reinforce the importance of early POST weed control in corn.

Sclerotinia sclerotiorum infects a broad range of plant hosts, and is typically identified by the production of white mycelium and black sclerotia on infected plants and culture. Isolates of S. sclerotiorum with darkly-pigmented mycelium have been reported on Valencia peanut in New Mexico and Texas. This study was conducted to determine the relationship between dark pigmentation in mycelium, oxalic acid production, and pathogenicity of S. sclerotiorum on Valencia peanut. A darkly-pigmented (SD) and a mutant, non-pigmented (SW) isolate of S. sclerotiorum were compared for vegetative growth on various growth media under different environmental conditions, and for pathogenicity on peanut. The SD isolate became darker in mycelium pigmentation as temperature increased beyond 20 °C and at pH between 5.0 and 6.0. Pigmentation in the SW isolate remained unaffected. Oxalic acid production did not increase in either SD or SW isolates when grown on media amended with pure oxalic acid or its precursor arabinose. The SD isolate caused peanut plant death and necrotic lesions on leaflets, while the SW isolate did not cause any symptoms. The differential behavior of SD and SW isolates in pathogenicity does not appear to be associated with mycelium pigmentation.

To clarify the theoretical basis of the differences in high temperature stress tolerance among herbaceous peony (Paeonia lactiflora Pall.), we investigated the heat injury index of twelve P. lactiflora cultivars. Of these, heat-tolerant ‘Zifengyu’ and moderately heat-tolerant ‘Hongyanzhenghui’ were selected to study the biochemical and molecular responses to high temperature stress. ‘Zifengyu’ had reduced malondialdehyde (MDA) content, increased soluble sugar, chlorophyll (Chl) a, Chl b, Chl a b. and carotenoid contents, as well as elevated antioxidant enzymes activities, photosynthetic rate (Pn), transpiration rate (Tr) and relatively intact cellular structures compared with ‘Hongyanzhenghui’, especially when the temperature was the highest. Additionally, we isolated partial cDNAs of two heat shock protein genes (HSP60 and HSP90) from P. lactiflora, which were 880-bp and 1077-bp nucleotides in length, respectively. The expression levels of PlHSP60, PlHSP70 and PlHSP90 were lower in ‘Zifengyu’ than in ‘Hongyanzhenghui’ for the first three of four developmental stages examined. These results indicated that heat-tolerant P. lactiflora cultivar could effectively scavenge reactive oxygen species (ROS), protect cellular structures, reduce thermal damage and delay the death of plants by enhancing antioxidant enzymes activities and HSP expression under high temperature stress. These findings provide a theoretical basis for breeding heat-tolerant P. lactiflora cultivars.

Water stress treatments on some morphological, biomass, physiological, biochemical characteristics and budding success of apricot and plum cultivars/Myrobolan 29 C plum rootstock have been studied in a pot-experiment trial. Three different water stress levels (control-100 %, medium-75 %, and severe-50 % of the pot capacity) were applied. The results showed that measured morphological, biomass, physiological and biochemical characteristics as well as budding success of cultivars on the rootstocks were affected by water stress. Water stress, both moderate and severe, significantly decreased the relative shoot length, diameter and shoot stem cross sectional area, plant total fresh and dry weights. Increases in water stress led to increases in peroxidase activities, phenol and proline contents in plum rootstock. Increases in water stress also resulted in reduction in budding success in both Formosa (plum cv)/Myrobolan 29 C (90.00 % and 48.33 %) and San Castrese (apricot cv)/Myrobolan 29 C (87.50 % and 42.83 %).

In this study, 43 elite clones of Populus deltoides were fingerprinted with ABI 3730 capillary electrophoresis by using six SSR primer pairs. Based on the fingerprinting profiles, 62 polymorphic bands were generated with a mean number of 10 alleles per locus, and allele numbers amplified by each primer in these clones ranged from 5 (NJFUP-poly10) to 16 (NJFUP-poly07). The power of discrimination values for these primer pairs ranged from 0.80 to 0.94, with an average value of 0.89. Among the six primer pairs, the most efficient primer pair for genetic discrimination of these elite clones was NJFUP-poly02, which could identify 22 of the 43 elite clones directly. In conclusion, all the 43 elite clones of P. deltoides could be discriminated unambiguously based on their genotypes at the six SSR loci. The combination of all six loci gave considerable reliability and accuracy for genetic identification of these clonal accessions. Subsequently, genetic relationship of these clones was plotted by the UPGMA clustering and principle component analysis. Results of both analyses indicated that clone “C7-1” had the largest genetic distance from the other clones, followed by clone “C51-1” and a subgroup comprising clone “C100-3” and “C62-3”. These clones are proposed to be possibly more affected by the inter-specific gene introgression.

The effects of supplementary lighting with high-pressure sodium (HSP) lamps alone or in combination with carbon dioxide (CO₂) on the growth, yield, and flower stem quality of two rose cultivars (“Loving Heart” and “Top Grace”) were studied. Compared to natural lighting (control), supplementary lighting alone was beneficial for plant growth, and it increased plant height, stem diameter, and the number of axillary shoots. Furthermore, increases in flower stem yield (>70 cm), flower stem diameter, fresh weight, and the number of petals per flower were also observed. The combination of supplementary lighting and CO₂ significantly enhanced all of the studied parameters compared to supplementary lighting alone. Moreover, stomatal density and chlorophyll fluorescence were seemingly affected by either supplementary lighting alone or in combination with CO₂. This is the first study to examine the beneficial effects of combined supplementary lighting and CO₂ conditions, and the resulting information is essential to rose growers and commercial production.

A study was conducted to compare the efficacy of nano-silver (NS), silver thiosulfate (STS), and silver nitrate as novel postharvest treatments, and evaluate the potential of nano-silver pulse (higher concentration) or vase (lower concentration) applications on postharvest performance of cut gladiolus (Gladiolus hybrids ‘White Prosperity’) spikes. Among silver compounds, spikes kept in silver nitrate had longest vase life. Spikes placed in STS at 10 or 20 mg L^-1 had longer vase life than stems placed in NS, but similar to the stems placed in water. For NS pulse applications, spikes pulsed with 50 mg L^-1 NS for 1 h at 20 ± 2 °C had 2.2 d longer vase life compared to the spikes in water. Pulsing of spikes for 1 h extended the vase life of cut gladiolus compared with 4 or 8 h pulsing durations. Spikes kept continuously in NS until end of vase life resulted in 4.2 d longer vase life at a lower concentration of 0.01 mg L^-1. With increasing NS concentration to 10 mg L^-1, vase life decreased to similar vase life as with tap water. The results demonstrated that NS at a 50 mg L^-1 pulse for 1 h or 0.01 mg L^-1 vase application can be used for extending vase life of cut gladiolus spikes.

Parata is a hard red spring wheat developed at the University of Alberta. In three years of testing in the Parkland Cooperative Registration Test, Parata was higher yielding (P < 0.05) than AC Splendor (5.9 %) and CDC Teal (4.1 %) but similar to CDC Osler and AAC Connery. Parata matured earlier than CDC Teal, CDC Osler and AAC Connery and 1.6 days later than AC Splendor. Parata was shorter than all checks except AAC Connery and exhibited lodging resistance better than AC Splendor and CDC Osler. Test weight of Parata was greater than all checks by at least 1 kg hL^-1, while seed mass was within the range of the check cultivars. Parata was rated resistant to the prevalent races of stem and stripe rust in three years of testing. It was rated R/MR in two years and MS in one year for leaf rust; and was I in two years and S in one year for common bunt. The FHB disease indices for Parata ranged from MS (1 rating) to MR in six station years. Three years of end-use quality evaluation has indicated that Parata is acceptable for the CWRS class, with improvements especially in flour yield and flour ash.