bluuebunny/crossref_metadata_2025 huggingface dataset:
A survey of ACCase inhibitor resistant wild oat in a high risk township in Manitoba
Authors: Bourgeois Luc , Morrison Ian N.
Published: April 2011

A survey was conducted in a township near Treherne, Manitoba to determine the frequency of Group 1 resistant wild oat in 30 randomly selected cereal fields. On average, 61% of the 30 fields were sprayed annually with ACCase inhibitor (Group 1) herbicides from 1983 to 1993. Wild oat were sampled at 80-m intervals on a predefined grid pattern across whole fields. Wild oat densities were recorded and seeds were collected from 0.25 m−2 quadrats. Seeds were also collected from conspicuous wild oat patches occurring outside the spaced quadrats. Plants were determined to be susceptible or resistant to fenoxaprop-P and/or sethoxydim using a seed bioassay procedure. Results from the structured survey indicated that resistant wild oat occurred in nine fields. Densities in quadrats containing resistant wild oat were generally higher than in quadrats with susceptible wild oat. By combining the results of the structured survey with the patch collection, resistance was detected in 20 out of the 30 fields. While resistant weeds generally occurred in small patches, in two of the fields, resistant plants occurred over much larger areas. The evidence suggests that as many as two fields in three may harbour Group 1 resistant wild oat in high risk townships in Manitoba. Key words: Weed survey, resistance assessment, wild oat, ACCase inhibitors
Screening methodology for post-harvest fungal resistance in alfalfa
Authors: Wittenberg K. M. , Smith S. R. , Katepa-Mupondwa F. , Yang J. F.
Published: April 2011

Forage deterioration due to field and storage fungi represents a major economic loss for hay producers. A series of experiments was conducted to develop a methodology for screening alfalfa plants for resistance to post-harvest fungal colonization. Pure cultures of Aspergillus glaucus, Aspergillus repens, Aspergillus flavus, Aspergillus versicolor and Aspergillus fumigatus, isolated from alfalfa forage sampled during field wilting and storage, were established and maintained to produce a 105 spore mL−1 suspension containing an equal proportion of spores from each Aspergillus spp. Alfalfa leaves were dipped in concentrations of propionic acid solution to simulate levels of resistance to fungal activity. Fully-developed trifoliate leaves were placed adaxial side down onto petri plates containing a dichloran (2 mg mL−1) and glycerol (18% vol/vol) agar. The Aspergillus spp. spore suspension was sprayed onto each petri plate and the plates were incubated under dark conditions at 25 °C and 70% relative humidity. Plates were monitored daily for percent of leaf area colonized. The random screening of a small population of cloned alfalfa genotypes using this screening procedure indicated that variation in post-harvest resistance to fungal attack does exist for greenhouse and field-grown plants harvested at an early vegetative stage. Leaf dry matter was not related to genotype variation in post-harvest susceptibility to fungal colonization; however, leaf soluble carbohydrate level was negatively correlated (P < 0.05) with leaf area colonized. The screening procedure did not detect consistent differences among genotypes when dried leaves were used. Key words: Alfalfa, genotype, post-harvest fungi, Aspergillus spp., resistance, screening
Effect of row spacing and seed/fertilizer placement on agronomic performance of wheat and canola in zero tillage systems
Authors: Xie H. S. , Rourke D. R. S. , Hargrave A. P.
Published: April 2011

Field experiments were carried out in Manitoba to investigate the agronomic response of zero till-grown spring wheat (Triticum aestivum L.) and canola (Brassica napus L.) to different row spacing and seed/fertilizer placement treatments. Wheat yield was very poor at 51-cm row spacing in comparison with those at 25- and 38-cm row spacings. Wheat performance between the row spacings of 25- and 38-cm was generally similar, especially coupled with paired-row seed/fertilizer placement; and canola performance tended to be better at 38-cm row spacing relative to 25-cm row spacing. Among three types of seed/fertilizer placement examined, paired-row placement resulted in the best performance in both wheat and canola, whereas crop response to narrow-row and wide-row seed/fertilizer placement varied with year. Therefore, with intensive crop management in zero tillage (ZT) system under the Manitoba conditions, the best crop performance in wheat and canola could be achieved with paired-row seed/fertilizer placement coupled with 25- to 38-cm row spacings. Key words: Yield, yield component, row spacing, seed/fertilizer placement, zero tillage
AC Norboro spring wheat
Authors: Nass H. G. , Johnston H. W. , Atlin G. N. , Mellish D. , Walker D. W.
Published: April 2011

AC Norboro is a spring feed wheat (Triticum aestivum L. em. Thell.) with high grain yield and early maturity. It is moderately resistant to powdery mildew, and susceptible to leaf blotch. AC Norboro is slightly more susceptible to fusarium head blight than AC Wilmot, Belvedere, and AC Baltic. AC Norboro was developed by Agriculture And Agri-Food Canada. Key words: Triticum aestivum, wheat (spring), cultivar description
Castor high erucic acid, low glucosinolate summer rape
Authors: McVetty P. B. E. , Rimmer S. R. , Scarth R.
Published: April 2011

Castor summer rape (Brassica napus L.) is a high-erucic acid rapeseed cultivar with canola-quality meal. Castor has an average 4% yield advantage over Mercury rapeseed and is 4 g kg−1 higher in seed oil than Mercury. Castor is adapted to the southern B. napus growing regions of western Canada. Key words: Rape (summer), high erucic acid-low glucosinolate, cultivar description
OAC Salem soybean
Authors: Tanner J. W. , Luzzi B. M. , Montminy W. , Gostovic P. , Hume D. J.
Published: April 2011

OAC Salem is a 2450 CHU soybean (Glycine max [L.] Merr.) cultivar. It has greater yield and plant height than check cultivars of similar maturity and normal oil and protein content. Key words: Soybean, cultivar description
KCl depresses physiologic leaf spot of barley (Hordeum vulgare L. 'Duke')
Authors: Zhang M. , Nyborg M. , Solberg E.
Published: April 2011

Physiologic leaf spot on barley in the greenhouse was suppressed with KCl fertilization. The area covered by the leaf spot was 8.1% without fertilization, up to 13.7% with K2SO4, but with KCl the amount was only 0.3 and 3.1% for 75 and 25 kg K ha−1, respectively. Suppression of the leaf spotting was not due to K+ or SO42−, but Cl−. Key words: KCl fertilization, Physiologic leaf spot
Comparative rooting of deciduous landscape shrub cuttings in media amended with paper mill biosolids from four different sources
Authors: Chong Calvin , Hamersma Bob , Bellamy Kevin L.
Published: April 2011

Scarcity of landfills has resulted in increasing need for alternative disposal or reuse of industrial organic wastes such as paper mill sludge (biosolids). The objective of this study was to evaluate and compare the rooting response of stem cuttings from six species of deciduous landscape shrubs [coralberry (Symphoricarpos × chenaultii Rehd. 'Hancock'); flowering almond (Prunus triloba Lindl. 'Multiplex'); honeysuckle (Lonicera × xylosteoides Tausch. 'Clavey's Dwarf'); mock orange (Philadelphus × virginalis Rehd. 'Minnesota Snowflake'); purple-leaf sandcherry (Prunus × cistena N. E. Hansen); and viburnum (Viburnum dentatum L.)] under mist and 50% shade (outdoor lath) in flats filled with 100% perlite medium, or perlite mixed with 15, 30, 45 or 60% of fresh paper mill biosolids, by volume, of one of four sources (Atlantic, Domtar, Thorold, and QUNO). There was little or no adverse effect of the biosolids, despite wide variability in rooting response due to species, source and/or level of biosolids. Regression analyses indicated that, with few exceptions, the percent rooting, mean root number per rooted cutting, and length of longest root per cutting increased linearly or curvilinearly, or was unaffected, when regressed over level of biosolids. Optimum amounts of biosolids in the rooting medium ranged from 30 to 60% by volume. The electrical conductivities of the biosolids-amended media were acceptable (0.1–0.3 dS m−1) for rooting of woody cuttings and pore space characteristics were comparable to, or exceeded those of, perlite. Key words: Ornamentals, landscape plants, propagation, organic waste, paper mill sludge, waste recycling
Interaction of triapenthenol and environmental factors on the growth and flower bud formation of Gardenia jasminoides Ellis
Authors: Kamoutsis A. , Chronopoulou-Sereli A. , Holevas C.
Published: April 2011

The interaction effects between total solar radiation, air temperature and relative humidity with different concentrations of the plant growth regulator triapenthenol (Baronet) on the vegetative growth and the formation of flower buds of potted gardenia (Gardenia jasminoides Ellis) plants were studied in glasshouse experiments.Triapenthenol was applied as a soil drench at concentrations of 0, 70, 140 and 280 mg L–1 to plants under each of three radiation levels of about 250 (P1), 90 (P2) and 25 (P3) Wm−2. It was established that the maximum temperature was the most critical environmental factor to plant development at all radiation levels. Lengths of new lateral shoots after pinching and the number of flower buds/plant were significantly reduced when radiation was reduced and triapenthenol concentrations increased. The interaction between total radiation and triapenthenol concentration significantly affected the number of flower buds/plant. An increase in triapenthenol concentration and a reduction of total radiation caused increased wrinkling of the leaves.In the unshaded plot (P1), the 140 mg L−1 triapenthenol concentration produced high-quality plants that were shorter than the untreated ones with more flower buds/plant during the growth period. In the moderately shaded plot (P2), the best market-quality plants were those treated with 70 mg L−1 triapenthenol. Key words: Gardenia jasminoides, temperature, total solar radiation, triapenthenol, relative humidity
Low vapour pressure deficits: Historical frequency and effect on tomato yield in southwestern Ontario
Authors: Liptay A. , Tan C. S. , Ramsey R. , Drury C. F. , Hunt D. W. A. , Jewett T. , Weaver S. , Woodrow L.
Published: April 2011

An historical analysis of vapour pressure deficit was done to determine the frequency of very low vapour pressure deficits during June, July and August of the growing seasons, in Harrow, Ontario. The impetus for the analysis was a lack of yield response of processing tomatoes to fertigation in 1995 compared to other years or sites. In the historical analysis, 2 years, 1964 and 1995, were identified as having a high frequency of very low daily vapour pressure deficits during the growing season. The site of the experiment where low VPD was recorded was about 5 km north from the shore of Lake Erie. A site 27 km away from Harrow, and about 10 km north of Lake Erie, near Leamington, Ontario, had a normal, increased yield response to the fertigation treatment. Key words: Relative humidity, vapour pressure deficit, yield, tomato
Reaction of cowpea (Vigna unguiculata) cultivars to Striga gesnerioides races from Mali and Niger
Authors: Touré M. , Olivier A. , Ntare B. R. , Lane J. A. , St-Pierre C. -A.
Published: April 2011

Field, pot and laboratory experiments were performed to evaluate the resistance of 12 cowpea (Vigna unguiculata [L.] Walp.) accessions to two races of the parasitic weed Striga gesnerioides (Willd.) Vatke (witchweed) from Cinzana, Mali and Maradi, Niger. Cultivar IT82D-849 showed resistance to either S. gesnerioides race in field, pot and laboratory experiments. IT81D-994 and Suvita-2 were both resistant to S. gesnerioides from Cinzana, but were susceptible to S. gesnerioides from Maradi. The occurrence of distinct varietal specificity among S. gesnerioides races may indicate the existence of significant interpopulation genetic divergence. These results highlight the possibility that varietal resistance could be overcome by some races of the parasitic weed, emphasizing the necessity to perform cowpea selection for resistance to various S. gesnerioides races. Key words: Cowpea, parasite races, resistance, selection, Striga gesnerioides, varietal specificity
Population development of Pratylenchus penetrans in sweet corn cultivars under controlled conditions
Authors: Yu Qing , Potter J. W.
Published: April 2011

Thirteen randomly selected sweet corn cultivars were evaluated for their ability to support a population of root lesion nematode, Pratylenchus penetrans, in growth chamber and greenhouse studies. The cultivars Phenomenal, Northern Super Sweet, Monte Carlo, Extra Early Super Sweet and Sweet Heart supported significantly higher nematode populations than all other cultivars, both in growth chamber and greenhouse tests. Earlivee, Seneca Horizon, Lyric, Grant, and King Arthur supported the lowest populations of the nematode in both tests. Sweet corn cultivars with the SH2 gene supported higher nematode populations than did cultivars containing either the SE, or se or su genes. Cultivars with the SE gene supported higher nematode populations than did cultivars containing the se or su genes. Key words: Root lesion nematode, sweet corn cultivars, screening
Yield, quality and stress tolerance of barley mixtures in central Alberta
Authors: Jedel P. E. , Helm J. H. , Burnett P. A.
Published: April 2011

Intraspecific mixtures may be a means of enhancing the genetic variability of modern crops while retaining the advantages of yield, quality, and stress tolerance of modern cultivars. Two- and three-way barley (Hordeum vulgare L.) mixtures of the cultivars Abee, Noble, Tukwa and Virden, were studied at Botha, Lacombe and Olds, Alberta, from 1992 to 1994. Treatments consisted of the four cultivars as monocrops and in 6 two-way and 3 three-way mixtures grown at a seeding rate of 250 seeds m−2. Tukwa as a monocrop had the highest rank and best stability for grain yield of all the treatments. Grain yields of the mixtures usually fell between the yields of the respective monocrops and were often better than the weighted mean yield of the monocrops indicating that many mixtures were more effective at using resources than the monocrops. Of the mixtures, Tukwa:Noble, Tukwa:Abee:Virden and Noble:Virden had the best rankings and stability for grain yield. Test weights, kernel weights, percent thins, lodging, disease incidence and protein content of the mixtures were intermediate to those of the monocrops. Mixtures containing the two-rowed cultivar Abee had higher test weight and protein content than mixtures composed of only six-rowed cultivars. Lodging and disease ratings were lower for the mixtures composed of only six-rowed cultivars than those with Abee. In these intraspecific barley mixtures, Virden was often the most competitive cultivar while Tukwa was the least. Competitive ability was not associated with yield potential, tillering, or row-type. Key words: Hordeum vulgare L., mixtures, yield, quality, stress tolerance
Annual legumes as green manure and forage crops in winter canola (Brassica napus L.) rotations
Authors: Shrestha Anil , Hesterman Oran B. , Copeland Lawrence O. , Squire John M. , Fisk John W. , Sheaffer Craig C.
Published: April 2011

Cropping systems that reduce chemical fertilizer N requirements in winter canola (Brassica napus L.) need further study. Studies were conducted in 1994/1995 and 1995/1996 at two locations in Michigan i) to quantify the N accumulated at plowdown by berseem clover (Trifolium alexandrinum L.), alfalfa (Medicago sativa L.) and three annual medic species (Medicago truncatula Gaertn., M. polymorpha L., and M. scutellata L.) when they were managed as green manure or managed as forage; ii) to compare N response of the winter canola crop following the legumes; and iii) to estimate the N fertilizer replacement value (FRV) of the legumes. The legumes were seeded in early May in both years. Winter canola was planted after legume plowdown 90 d after planting (DAP). Four N rates (0, 50, 100, and 150 kg N ha−1) were applied to the winter canola in early spring. Herbage N yield at plowdown was highest (103.9 kg N ha−1) in berseem clover managed as green manure and this treatment resulted in the highest winter canola yield in 1995, but treatment differences were not significant in 1996. A supplementary effect of some treatments on winter canola yield was observed in 1995. Fertilizer N had a similar effect on winter canola yield across all treatments, and resulted in a quadratic response in 1995 and a linear response in 1996. Winter canola grain yield following annual legumes managed as green manure or as forage were similar. Winter canola yield following berseem clover was higher than when following annual medics. No FRV of legumes on winter canola was observed. Key words: Annual medics, berseem clover, winter canola, Medicago spp., Trifolium alexandrinum L., Brassica napus L., green manure, crop rotation
OAC Thunder common bean
Authors: Michaels T. E. , Smith T. H.
Published: April 2011

OAC Thunder is an indeterminate bush white bean (Phaseolus vulgaris L.) cultivar intended for use in areas with greater than 2600 crop heat units. It has excellent yield potential in either wide or narrow row production and is resistant to races 1 and 15 of bean common mosaic virus. Seed has acceptable cooking and canning quality. Key words: Phaseolus vulgaris L., white bean, common bean, cultivar description
AC 2001 soybean
Authors: Voldeng H. D. , Guillemette R. J. D. , Cober E. R.
Published: April 2011

AC 2001 is a 700 crop heat unit soybean [Glycine max (L.) Merr.] cultivar with good yield potential. Key words: Soybean, cultivar description
AC Alberta Pink bean
Authors: Saindon Gilles , Mündel Hans-Henning , Huang Henry C. , Kiehn Ferdinand A.
Published: April 2011

AC Alberta Pink is a large-seeded, high-yielding dry bean (Phaseolus vulgaris L.) cultivar. It was developed at the Lethbridge Research Centre in cooperation with the Morden Research Centre from a cross of ISB473/4/NW63/3/Swan Valley/2/Redkloud/Kentwood. AC Alberta Pink is particularly well adapted to the irrigated western Canadian prairies, exceeding Viva by 13% in yield, 16% in seed weight, and maturing on average 2 d earlier than Viva. Key words: Phaseolus vulgaris, pink bean, cultivar description, large seed weight
Grass leaf blade development: Modification of the source
Authors: Brégard A. , Allard G.
Published: April 2011

Developing leaf blades of tall fescue (Festuca arundinacea Schreb.) were subjected to three treatments that modify their source capacity: (1) emerged tips cut daily, (2) grown in darkness or (3) grown at the CO2 compensation point. Treated and control leaves developed similarly but treated leaves senesced rapidly at the leaf tip. Reduction of carbon availability in developing tall fescue leaf blades seems not to penalize normal blade development but does reduce the lifespan of mature leaves. Key words: Source, leaf development, tall fescue
Silken apple
Authors: Quamme H. A. , MacDonald R. A. , Lane W. D. , Hampson C. R.
Published: April 2011

Silken is a new early-maturing apple cultivar ripening in the same season as McIntosh with a unique creamy skin colour. It is crisper and sweeter, and possesses a higher aromatic intensity than Royal Gala or McIntosh. In preference tests, it has been rated equal to Gala and better than McIntosh in Flavour and texture. It can be stored for 10 wk at 0 °C. Key words: Malus domestica Borkh., dessert apple, cultivar description
MillenniUM 01 high erucic acid, low glucosinolate summer rape
Authors: McVetty P. B. E. , Scarth R. , Rimmer S. R.
Published: April 2011

MillenniUM 01 summer rape (Brassica napus L.) is a high-erucic acid, low-glucosinolate (i.e. canola-quality meal) cultivar. It has an average 7% yield advantage over Reston high erucic acid, low glucosinolate summer rape, is 11 g kg−1 higher in seed oil content than Reston, 25 g kg−1 higher in meal protein content than Reston, and is adapted to the southern B. napus growing regions of western Canada. Key words: Rape (summer), high erucic acid, low glucosinolate, cultivar description
Herbicide residues and yield effects from repeated flood-irrigations of alfalfa with water containing monuron or simazine
Authors: Jame Y. W. , Cessna A. J. , Biederbeck V. O. , Grover R. , Smith A. E. , Korven H. C.
Published: April 2011

Surface runoff or irrigation water contaminated with herbicides may cause crop damage and result in inadvertent residues in the crop. Rotational crops may also be damaged due to the persistence of leached herbicides within the root zone. An 11-yr field experiment was carried out to address these issues through repeated flood-irrigations of alfalfa (Medicago sativa L. 'Roamer') with water containing various concentrations (0, 10, 100 and 1000 µg L−1) of monuron or simazine. The experimental site, on an alluvial clay soil, was flood-irrigated for 8 yr with a total of 32 irrigations, then oat (Avena sativa L. 'Harmon') was grown for 3 yr under dryland conditions as a sensitive bioassay crop. Based on alfalfa forage yield, repeated applications of water containing up to 100 µg L−1 of either monuron or simazine did not show any harmful effects on the crop. However, the 1000 µg L−1 treatments caused cumulative yield reductions with greatest deleterious effect being caused by simazine (up to 55% yield reduction). After 7 yr of irrigation, inadvertent residues of both herbicides were consistently detected in the crop, but only for the 1000 µg L−1 treatments. Average concentrations of monuron in the alfalfa foliage were 0.94 and 1.76 mg kg−1 for the first and second cuts, respectively, whereas corresponding values for simazine were 0.31 and 0.64 mg kg−1. Approximately 4 and 12% of the total amounts applied remained in the soil profile for monuron and simazine, respectively. Herbicide residues to 1.5 m soil depth decreased with increasing depth with half of the total being present in the top 0.15 m, and they were detectable only for the 100 and 1000 µg L−1 treatments. Only soil residues of simazine from the 1000 µg L−1 rate of application reduced oat yields extensively. These yield reductions occurred only during the first 2 yr under dryland production. Key words: Herbicide-contaminated irrigation water, crop damage, herbicide residues, alfalfa, simazine, monuron
A method to characterize root morphology traits in alfalfa
Authors: Lamb J. F. S. , Johnson L. D. , Barnes D. K. , Marquez-Ortiz J. J.
Published: April 2011

Productivity in alfalfa (Medicago sativa L.) has been shown to be influenced by root morphology. Our objectives were to identify the optimum age, cultural practices, and environmental conditions to characterize taproot diameter (TD), lateral root number (LRN), fibrous root mass (FRM), and determinate taproot percentage (DTP) in alfalfa. No correlations were found between greenhouse-cultured plants and 21-wk-old field-grown plants for LRN or FRM, while TD showed low to moderate correlations between greenhouse and field environments. Fourfold more plants with determinate taproots were identified in transplanted plots compared to seeded plots. All root traits were affected by plant spacing but, no germplasm × plant spacing interactions were found. Solid seeded plants needed more time to show maximum expression of root traits and scored lower for LRN and FRM and had smaller TD than spaced plants. Only TD had a significant germplasm × location interaction. Both TD and LRN increased with N fertilizer and between the seeding and first production years, but no germplasm × N rate or germplasm × year interactions were found. Rankings of alfalfa germplasms were the same at the end of the seeding year (22 wk after planting) and at the end of the first production year (74 wk after planting). Characterization of LRN and FRM in alfalfa should be conducted in seeded field plots with uniform plant spacing at one location, with or without N fertilizer at least 22 wk after planting. A similar protocol with evaluation at more than one location would be more appropriate for characterization of TD. Key words: Medicago sativa L., root morphology, alfalfa
Within-season grass yield and nitrogen uptake, and soil nitrogen as affected by nitrogen applied at various rates and distributions in a high rainfall environment
Authors: Kowalenko C. G. , Bittman S.
Published: April 2011

A study was conducted to assess the effect of rates of nitrogen (N) fertilizer, and to compare the effectiveness of single and split applications of N on yield and quality of forage grass and on the potential for nitrate leaching. Three field trials were conducted at different sites in successive years, with plant and soil measurements made at each of four harvests. Extractable inorganic N was measured to 0.6 m in three depth increments prior to spring N application and after each cut in order to evaluate immediate and residual effects of the N fertilizer on plant growth, and the environmental implications of the applications. Response of yield and N uptake to N applications differed in the three trials. In all trials, the effect of N rate was greater than the effect of N distribution during the growing season. Although there were only small, whole-season yield increases associated with distributing the N over the season, the distribution of yield within the season was changed considerably. Soil data showed relatively little leaching of N during the growing season under contrasting weather conditions of the three growing seasons. Retention of N within the soil root zone contributed to residual effects on yield and plant uptake, and these effects frequently lasted to the end of the growing season. Crop response to N applications was apparently influenced by the N supplying capacity of the soil and the effect of weather on crop growth rate. Soil nitrate at harvest did not vary consistently with N application treatments in the three trials, other than having highest concentrations at the highest fertilizer rate. Soil nitrate was greatest after cut 1 and decreased sharply toward the end of the season following the single spring applications, whereas plots receiving equal distributions of N through the season had relatively high concentrations at all sampling times during the season. Soil extractable ammonium concentration was influenced by high rates of N application, but the effect was small and largely confined to the sampling after cut 1. The soil always contained about 10–15 mg kg−1 extractable ammonium in surface 0.3 m depth, with a tendency for slightly greater concentrations in early spring. Soil ammonium appears to be involved in soil and plant processes, but the exact magnitude and significance of its involvement could not be determined from the measurements made. The redistribution of grass yield by splitting the application of fertilizer N within the growing season would be beneficial for grazing systems. Unfortunately, soil inorganic N measurements will not greatly assist in determining the precise rate and distribution of fertilizer for varying field conditions. Key words: N response, N uptake, residual N effect, soil extractable N, N leaching
Physiological mechanism of tolerance of Lycopersicon spp. exposed to salt stress
Authors: Rajasekaran Lada R. , Aspinall D. , Paleg L. G.
Published: April 2011

The physiological mechanism of salt tolerance in Lycopersicon spp. was investigated. Ten Lycopersicon spp. were exposed to a gradual NaCl-induced decline in root zone water potential of −0.10 MPa d−1 for 10 d and maintained at −1.065 MPa (221.4 mM NaCl) for a period of 20 d. Growth, water relations and accumulation of ions and compatible solutes, such as proline and the quaternary ammonium compound, trigonelline (methylated nicotinic acid), were studied and correlated. Salt tolerance, measured as growth, in selected Lycopersicon species of varying ecological habitats indicated that L. cheesmanii, native to a saline-coastal habitat, was the most tolerant and L. pennellii, the most sensitive. The commercial cultivar, L. esculentum 'Duke', ranked 7th in the order of relative tolerance to salt. All species accumulated proline in all organs in response to salinity; but there was no general relationship between the ability of these species to accumulate proline and their relative salt tolerance. Relative trigonelline accumulation in meristematic tissues of NaCl-stressed plants correlated with the salt tolerance of these species, however, as did their ability to (1) maintain turgor in the expanding leaves, (2) exclude Na+ from the expanded leaves and (3) exclude Cl− from the root tissues. Key words: Chloride accumulation index, Lycopersicon spp., proline accumulation index, salt tolerance index, sodium accumulation index, trigonelline accumulation index, water potential
Quackgrass (Elytrigia repens) management in flax (Linum usitatissimum)
Authors: Wall David A. , Smith Marjorie A.H.
Published: April 2011

Field studies were conducted at the Agriculture and Agri-Food Canada, Research Centre, Morden, Manitoba from 1992 to 1996 to evaluate quackgrass management in flax with several graminicides applied at annual and perennial grass rates, and with preharvest glyphosate applied after postemergence graminicides. All graminicides at both application rates reduced quackgrass biomass. However, at annual grass rates, clethodim and sethoxydim were sometimes less effective at controlling quackgrass than quizalofop and fluazifop-P. There was some evidence that annual-rate applications of sethoxydim can result in increased quackgrass regrowth in the second year. Flax seed yields were not affected by the use of graminicides at annual grass rates compared with perennial grass rates, whereas untreated (weedy checks) flax had yield losses of up to 67% compared with weed-free plots. The use of preharvest glyphosate reduced second-year regrowth of quackgrass by half or more, compared with no preharvest glyphosate treatment. Where preharvest glyphosate had been applied, the weedy checks tended to have markedly less quackgrass regrowth than where graminicide treatments had been applied in the spring. This suggests that use of spring-applied graminicides may reduce the effectiveness of preharvest glyphosate to control quackgrass. However, use of a postemergence graminicide is often necessary to control annual grasses as well as quackgrass because flax yield is seriously affected by uncontrolled weed growth. A second experiment was conducted to compare the efficacy of liquid and dry formulations of glyphosate applied with water and 28-0-0 fertilizer as carriers. The three glyphosate formulations applied at 0.9 kg a.e. ha−1 were equally effective at reducing quackgrass biomass in flax without yield loss, but at 0.45 kg a.e. ha−1, the liquid formulation was sometimes less effective. There was no consistent evidence that the use of liquid urea/ammonium nitrate fertilizer as a carrier, rather than water, affects the performance of either liquid or dry glyphosate formulations. Key words: Quackgrass, flax, graminicides, glyphosate, preharvest application
Utilization of doubled haploid technique in Brassica rapa population improvement
Authors: Friesen H. , Scarth R.
Published: April 2011

The utilization of doubled haploid (DH) plants in population improvement of Brassica rapa was studied by randomly intercrossing 4, 8, 12 and 22 DH lines developed from the B. rapa cultivar Reward and the B. rapa breeding line DSC3 for two generations to constitute synthetic populations. The synthetic populations and the DH plants used in their formation were evaluated for agronomic performance at two locations in the field in 1996 and for genetic variation using random amplified polymorphic DNA (RAPD) analysis. Intercrossing as few as four DH lines from the breeding line DSC-3 produced a synthetic population with improved performance over that of the contributing DH lines. The synthetic population produced from the interpollination of eight DH lines showed an agronomic performance over that of the contributing DH lines to a level similar to the Reward donor population. RAPD analysis efficiently characterized the genotypic variation present in DH lines and synthetic populations, detecting 22–72% polymorphism between DH lines, 17–53% and 27–47% polymorphism in the first and second synthetic populations, respectively. This characterization may be useful as a tool in the reestablishment of heterogeneity and recovery of agronomic performance in B. rapa synthetic populations derived from DH lines by determining the level of genetic variability among DH lines and therefore optimal population size. Key words: Brassica rapa, synthetic population, doubled haploids, RAPD, agronomic performance
Residues of glyphosate and its metabolite AMPA in canola seed following preharvest applications
Authors: Cessna A. J. , Darwent A. L. , Townley-Smith L. , Harker K. N. , Kirkland K. J.
Published: April 2011

Residue data for glyphosate and its major metabolite aminomethylphosphonic acid (AMPA) in canola seed following preharvest application of glyphosate were lacking when this 2-yr study was initiated. Residues of glyphosate and AMPA were measured in the seed of canola (Brassica rapa L.) at maturity following preharvest application at rates of 0.45, 0.9 or 1.7 kg acid equivalent ha−1 at four sites in western Canada. Herbicide treatments were applied in early August to mid-September at four stages of crop development, which encompassed seed/pod moisture contents ranging from 74 to 12%. Rate of glyphosate application and the physiological maturity of the crop at application played important roles in determining the magnitude of glyphosate and AMPA residues in the seed of preharvest-treated canola. In general, for a given site, mean residues of glyphosate and AMPA in the seed increased with increasing application rate, and decreased with application at later stages of crop development. In 1989, mean residues of glyphosate in the seed for all application rates at the latest stage of development at each site were <1 mg kg−1. In 1988, when seed/pod moisture content generally declined very slowly from stage 1 to stage 3 and then decreased rapidly, corresponding mean residues were higher and varied from <1 to 19.7 mg kg−1. Seed/pod moisture was not a reliable indicator of stage of canola development and, consequently, the magnitude of glyphosate and AMPA residues in the seed. Key words: Glyphosate residues, AMPA residues, canola, preharvest treatment
Damage to wheat seeds caused by a plant bug, Lygus lineolaris L.
Authors: Wise I. L. , Tucker J. R. , Lamb R. J.
Published: April 2011

Adults of the plant bug, Lygus lineolaris L., cause bleached areas on wheat seeds when they feed. Affected areas are irregular in shape and extend into the endosperm, with necrotic lesions where the insects' mouthparts puncture the surface. This seed damage occurs in commercial wheat from many parts of western Canada. Key words: Starchy seeds, non-vitreous kernels, durum wheat, seed damage
RCAT Legacy soybean
Authors: Ablett G. R. , Stirling B. T. , Fischer J. D.
Published: April 2011

RCAT Legacy is an early Maturity Group II soybean [Glycine max (L.) Merr] cultivar with excellent yield potential and good lodging resistance. It was developed by Ridgetown College, University of Guelph and is widely adapted to Ontario. Key words: Soybean, cultivar description, Glycine max
SW33-08 soybean
Authors: Ablett G. R. , Stirling B. T. , Fischer J. D.
Published: April 2011

SW33-08 is an early Maturity Group III soybean [Glycine max (L.) Merr]. cultivar with excellent yield potential and good lodging resistance. It was developed by Ridgetown College, University of Guelph and adapted to the long season areas of S.W. Ontario. Key words: Soybean, cultivar description, Glycine max
The biology of Canadian weeds. 112. Ulex europaeus L.
Authors: Clements David R. , Peterson David J. , Prasad Raj
Published: April 2011

Gorse (Ulex europaeus L.) is a leguminous shrub native to western Europe and North Africa. During the past century it has greatly expanded its adventive range in Australia, New Zealand, Chile and Europe, and along the Pacific and Atlantic coasts of North America. In Canada, it is found in British Columbia (Vancouver, Vancouver Island, the Gulf Islands and Queen Charlotte Islands) where it is classed as a noxious weed. Gorse is also found from Virginia to Massachusetts on the east coast of North America. The shrub rapidly invades dry and disturbed areas, forming dense thickets that can suppress and inhibit native vegetation, including economically important conifer seedlings. It can occupy the same habitats as Scotch broom [Cytisus scoparius (L.) Link] but usually occurs on drier sites. Both of these legumes threaten native plant communities but U. europaeus persists longer and possesses conspicuous spines. Invasive characteristics of gorse include its evergreen habit, prolific seed production, longevity of seeds in the soil and nitrogen fixation. Human activities such as agriculture and construction of logging roads have accelerated the spread of gorse in British Columbia, but there is still an historic opportunity to restrict the population expansion that this species has exhibited in many other countries. Various methods of control (chemical, manual, biological and integrated) are evaluated. Key words: Ulex europaeus, Cytisus scoparius, exotic plant, biological control, Exapion ulicis
Diplotaxis muralis (mur) cytoplasmic male sterility system maintainer occurrence and frequency in summer rape
Authors: Riungu Teresio C. , McVetty Peter B. E.
Published: April 2011

No male sterile plants were found in the F1 progeny from crosses between a Diplotaxis muralis cytoplasmic male sterile (mur CMS) semi-winter habit rape (Brassica napus L.) A-line and 101 genetically diverse summer rape cultivars or strains. The frequency of occurrence of mur CMS system maintainer genotypes in summer rape is very low, possibly zero. Key words: Mur CMS system; Brassica napus L.
Accord soybean
Authors: Voldeng H. D. , Guillemette R. J. D. , Cober E. R.
Published: April 2011

Accord is a 2450 crop heat unit soybean [Glycine max (L.) Merr.] cultivar with good yield potential. Key words: Soybean, cultivar description
CG107 corn inbred line
Authors: Lee E. A. , Good B. , Chakravarty R. , Kannenberg L.
Published: April 2011

CG107 is a short-seasoned corn (Zea mays L.) inbred line. CG107 exhibits excellent combining ability and stalk quality in hybrids, and superior late season plant health per se. Key words: Corn, Zea mays L., cultivar description
Heron soybean
Authors: Voldeng H. D. , Frégeau-Reid J. A. , Cober E. R. , Guillemette R. J. D.
Published: April 2011

Heron is a 2650 crop heat unit soybean [Glycine max (L.) Merr.] cultivar developed for natto soyfood production. Key words: Soybean, cultivar description, natto
Remediating Ni-phytotoxicity of contaminated Quarry muck soil using limestone and hydrous iron oxide
Authors: Kukier Urszula , Chaney Rufus L.
Published: April 2011

Remediation of excessive soil metals in situ is receiving new attention because the alternative, soil removal and replacement, is very expensive, requires disposal of the removed soil and may achieve no better environmental remediation than the in situ treatments. A factorial pot experiment was conducted with two muck soils contaminated by a Ni refinery; we tested the effectiveness of making the soil calcareous and addition of freshly precipitated hydous ferric oxide (HFO) in reducing soil Ni phytotoxicity to the Ni-sensitive crops, oat and redbeet, and a Ni-resistant crop, wheat. Fertilized but otherwise untreated soil caused significant Ni phytotoxicity to oats and redbeet, but not to wheat, on both soils. Adding limestone reduced the concentration of Ni in shoots of all species and alleviated the symptoms specific to Ni phytotoxicity in oat (banded chlorosis). The addition of HFO was more effective in reducing shoot Ni concentration in the redbeets than in crops from the Poaceae family. Both amendments induced phosphorus and/or manganese deficiency depending on the crop tested. The experiment indicates that some combination of limestone and Fe oxides can readily remediate Ni phytotoxicity of the tested soils, but that Mn and P fertilizers would be needed to achieve practical in situ remediation of Ni phytotoxicity of Quarry muck (Terric Mesisol). Key words: Nickel, soil, plant, phytotoxicity, remediation
Impacts of tillage practices on total, loose- and occluded-particulate, and humified organic carbon fractions in soils within a field in southern Ontario
Authors: Yang X M , Kay B D
Published: April 2011

The effects of no-tillage (NT) and moldboard plowing (MP) on the distribution and storage of soil organic carbon (SOC) and different C fractions were determined along a transect on a private farm in southern Ontario, Canada, where a paired NT and MP strip traversing three soil series had been in existence for 19 yr. Soil samples were collected to a depth of 60 cm in seven increments. SOC was determined in each sample and for the top 30 cm, the organic carbon was fractionated into loose-, occluded-particulate organic matter (loose-POM and occluded-POM) and humified fraction (HF). After 19 yr, soils under NT contained significantly (P < 0.05) more SOC than soils under MP on both an equivalent depth basis and an equivalent mass basis. Greater concentrations of loose- and occluded-POM were found in NT than MP surface soils (0-10 cm). MP favored higher loose-POM contents than NT practices at a depth of 10-20 cm. The HF fraction accounted for most of the increase in SOC in the Huron and Brady soils, whereas the occluded POM accounted for more of the increase in the Fox soil. Our results indicate that the extent of SOC sequestration under NT is strongly dependent on soil type and cropping history. Key words: Tillage practices, soil organic carbon, C fraction, C sequestration
Ammonia volatilization from soils fertilized with urea and varying rates of urease inhibitor NBPT
Authors: Rawluk C. D. L. , Grant C A , Racz G J
Published: April 2011

Loss of N as ammonia (NH3) from surface-applied urea fertilizer may be high if hydrolysis takes place at the soil surface. The urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) may reduce NH3 loss from urea by delaying hydrolysis. Field studies using surface chambers were conducted in 1996 and 1997 to compare the amount of NH3 volatilized from surface applications of granular urea (100 kg N ha–1) treated with varying concentrations of NBPT (0, 0.05, 0.10 and 0.15% NBPT wt/wt). The studies were conducted on two Orthic Black Chernozemic soils, a Stockton fine sandy loam and a Newdale clay loam, in May and again in July to determine the relative influence of soil texture and temperature on NBPT performance at the varying rates. Ammonia losses were measured at various times to 12 d after fertilization (DAF) in 1996 and to 21 DAF in 1997. Total NH3 losses decreased in the order of 0% > 0.05% > 0.15% > 0.10% where use of NBPT reduced total NH3 loss by 28-88% over the entire study duration, and by 82 to 96% during periods of peak loss from unamended urea. Ammonia volatilization losses from NBPT-amended urea treatments were lower in May than in July. The total loss measured at all rates of NBPT was higher for the fine sandy loam soil except in May 1997 where cool conditions resulted in slightly lower loss than for the clay loam soil. Amending urea with NBPT at a rate as low as 0.05% wt/wt can reduce NH3 loss from surface-placed urea fertilizer, so that a greater proportion of fertilizer N is retained in the soil for plant use. The inhibitor helps reduce the amount of NH3 derived from urea entering the atmosphere to react or to be deposited elsewhere, and may lessen the need to overfertilize to compensate for potential NH3 losses. Key words: N-(n-butyl) thiophosphoric triamide, urease inhibitor, surface applications
Impact of long-term cultivation on the status of organic matter and cadmium in soil
Authors: McArthur D. F. E. , Huang P M , Kozak L M
Published: April 2011

Research has suggested a link between the bioavailability of soil Cd and total soil organic matter. However, some research suggested a negative relationship between total soil organic matter and bioavailable soil Cd while other research suggested a positive relationship. This study investigated the relationship between soil Cd and both the quantity and quality of soil organic matter as influenced by long-term cultivation. Two Orthic Chernozemic surface soil samples, one from a virgin prairie and the other from an adjacent cultivated prairie, were collected from each of 12 different sites throughout southern Saskatchewan, Canada. The samples were analyzed for total organic C, total Cd, Cd availability index (CAI), and pH. The nature of the soil organic matter was investigated with 13C Cross Polarization Magic Angle Spinning Nuclear Magnetic Resonance spectroscopy (13C CPMAS NMR). The total soil Cd, CAI, and total soil organic C of the cultivated soils were significantly lower than those of the virgin soils whereas the opposite trend was observed for the soil pH and the aromaticity of the organic C. The reduced CAI in the cultivated soils was related to the increase in both the soil pH and the aromaticity of the organic C. No relationship was found between the CAI and the soil organic C content, but a significant positive correlation was found between total organic C and total Cd in both the virgin and the cultivated soils. As well, a significant positive correlation was found between the fraction of total Cd removed from the soil after long-term cultivation and the corresponding fraction of organic C removed. Key words: Long-term cultivation, soil organic matter, 13C CPMAS NMR, cadmium
Carbon-13 solid-state NMR of soil organic matter - using the technique effectively
Authors: Preston Caroline M
Published: April 2011

Solid-state 13C CPMAS NMR offers many options for characterizing carbon in soil organic matter (SOM). Its effectiveness, however, is often limited by a poor understanding of the techniques, and lack of hands-on access and training opportunities for students. Of nearly 250 modern NMR systems in Canada, approximately one is genuinely available for SOM studies, and there is poor communication between NMR operators and SOM users. While quantitative reliability can be addressed to some extent by multiple contact-time experiments or single-pulse (Bloch decay) spectra, it is also important to consider the effects of spectrometer background, spinning sidebands (especially with higher magnetic fields) and processing operations such as line-broadening, phasing and baseline correction. In many studies, more consideration needs to be given to instrument specifications, the type of information needed, and whether sample fractionation or pretreatment should be used. Structural information can be greatly enhanced by dipolar-dephasing and sideband suppression sequences. Sequences based on relaxation differences can reveal pools of carbon with different structures. Data analysis can be enhanced by principal component analysis, spectrum deconvolution and difference spectra. Studies of xenobiotics and C metabolism can be greatly aided by 13C-labeling. However, a key limitation to SOM applications remains the gap in culture and expectations of the users. Key words: Soil organic matter, 13C CPMAS NMR, Bloch decay, dipolar dephasing, spinning sidebands