bluuebunny/crossref_metadata_2025 huggingface dataset:
AC Lacombe barley
Authors: Kibite Solomon
Published: April 2011

AC Lacombe is a six-rowed feed barley (Hordeum vulgare L.) developed at Agriculture Canada, Lacombe Research Station from the cross Klondike/Galt/Unitan. It has plump kernels, high test weight, adequate lodging resistance, and good agronomic characteristics. AC Lacombe is recommended for the Black and Grey Wooded soils of western Canada, where it yields more than other registered cultivars. Key words: Hordeum vulgare, feed barley, cultivar description
AC Minto hard red spring wheat
Authors: Townley-Smith T. F. , Czarnecki E. M. , Campbell A. B. , Dyck P. L. , Samborski D. J.
Published: April 2011

Minto hard red spring wheat (Triticum aestivum L.) combines excellent resistance to leaf rust and stem rust with higher yield potential than Neepawa or Katepwa. Registered 29 January 1991, it is best adapted to the southern portions of the wheat-growing area of the Canadian prairies. Breeder seed of AC Minto will be maintained by the Agriculture Canada Experimental Farm, Indian Head, Saskatchewan. Key words: Cultivar description, spring wheat, Triticum aestivum L.
Pasqua hard red spring wheat
Authors: Townley-Smith T. F. , Czarnecki E. M. , Campbell A. B. , Dyck P. L. , Samborski D. J.
Published: April 2011

Pasqua hard red spring wheat (Triticum aestivum L.) combines excellent resistance to leaf rust and stem rust with increased sprouting resistance relative to Neepawa or Katepwa. Registered on 6 April 1990, Pasqua is adapted to the entire wheat-growing area of the Canadian prairies. Breeder seed of Pasqua will be maintained by the Agriculture Canada Experimental Farm, Indian Head, SK. Key words: Cultivar description, spring wheat, Triticum aestivum L.
Effects of foliar fungicide sprays on disease and yield of processing tomatoes in Ontario
Authors: Poysa V. , Brammall R. A. , Pitblado R. E.
Published: April 2011

The effects of controlling foliar diseases with a foliar fungicide applied following a TOMCAST regime were evaluated on commercial processing tomato (Lycopersicon esculentum Mill.) cultivars in three locations in Southwestern Ontario in 1990 and 1991. For each cultivar, one set of plants was sprayed with chlorothalonil (Bravo 500) and one set received no fungicide application during the growing season. At two of the three locations, fungicide application significantly reduced final foliar disease development, averaged across all cultivars, from over 60% of the foliage infected to 10% infected. At the third location disease development was more restricted. Use of foliar fungicide did not result in a significant increase in either total fruit yield or yield of marketable fruit measured across cultivars, years, and locations. The application of fungicide (4–10 sprays) reduced the average number of fruit infected with anthracnose by 50% over all cultivars treated. Several cultivars, however, had relatively low levels of anthracnose even without fungicide sprays. While fungicide sprays may be important in maintaining fruit quality, both with respect to solids levels and degree of mould contamination, fungicide may not be required to maintain yields every year for many tomato cultivars commercially grown in Ontario. Key words: Lycopersicon esculentum, tomato disease, anthracnose
The effect of fungicides and plant growth regulators applied as a seed treatment on the freezing tolerance of winter wheat
Authors: Gusta L. V. , O'Connor B. J. , Lafond G. P. , Austenson H. M.
Published: April 2011

Several plant growth regulators and fungicides, which inhibit gibberellin synthesis, were tested for their effect on the development of freezing tolerance of winter wheats (Triticum aestivum em Thell). Seeds of Norstar and Norwin were treated with either triadimenol; prochloraz, alone or in combination with imazalil; tetcyclasis; and carbathiin. The first four compounds are potent plant growth regulators that inhibit the production of gibberellins. The first three compounds, triadimenol, prochloraz and imazalil are also registered seed fungicides. Carbathiin, also a seed fungicide, has no known plant growth regulator activity. Prochloraz alone or in combination with imazalil and carbathiin initially delayed germination of both cultivars; after 144 h, however, germination was 90% or better for all treatments except the seeds of Norwin treated with carbathiin which were only 84% germinable. None of the fungicides increased the freezing tolerance of the Norstar crowns; however, carbathiin, tetcyclasis, triadimenol, prochloraz alone and in combination with imazalil (intermediate rate) reduced freezing tolerance. The freezing tolerance of Norwin, a semi-dwarf winter wheat, was reduced by tetcyclasis at the low and intermediate rate. In samples collected in the spring, the carbathiin treatment reduced the freezing tolerance of both Norwin and Norstar. None of the treatments affected the growth of the Norstar crowns in late October. Only triadimenol (intermediate rate) and tetcyclasis (intermediate and high rate) increased the crown moisture content. The carbathiin seed treatment increased the growth of Norwin crowns in the autumn. Nearly all of the treatments increased the crown moisture content of the Norwin crowns. In estimating spring vigour, only triadimenol (low rate) and tetcyclasis (intermediate rate) increased the leaf number of Norstar crowns, whereas nearly all treatments except tetcyclasis (intermediate rate) and prochloraz alone or in combination with imazalil increased leaf number of Norwin crowns. All rates of triadimenol and tetcyclasis, at the low rate, stimulated development of more roots for Norwin. The above seed treatment provide little or no benefit for the survival of winter wheats to a freezing stress. Key words: Winter wheat, seed treatment, fungicides, freezing tolerance
Screening timothy genotypes for nitrate reductase activity using an ELISA technique
Authors: Lapointe Gilles , Nadeau Paul , Vézina Louis-P. , Allard Guy
Published: April 2011

Timothy (Phleum pratense L.) is the most cultivated forage crop in Eastern Canada. Like most perennial grasses, ample amounts of nitrogen are needed to obtain adequate yields. A selection program to reduce the nitrogen requirements of timothy and improve its nitrogen use efficiency could be undertaken if a suitable method were developed to screen large plant populations and identify genotypes with high nitrate reductase (NaR) activity. An enzyme-linked immunosorbent assay (ELISA) using anti-barley (Hordeum vulgare L.) NaR immunoglobulin has been developed. It has been used to evaluate genetic variability for NaR activity in two timothy cultivars. Using the ELISA procedure, no significant differences in NaR activity were detected between the two cultivars. However, significant differences were observed between randomly selected genotypes within one of the two cultivars. The ELISA procedure repeatedly and accurately detected very small amounts of NaR activity. This procedure could enable the screening of large populations of timothy or other forage grasses for selection of genotypes with high NaR activity. The presence of genetic variability for NaR activity in timothy could be exploited in a selection program. Key words: Timothy, nitrate reductase, ELISA
Evaluating alfalfa cultivars and germplasms for pastures using the mob-grazing technique
Authors: Bittman S. , McCartney D. H.
Published: April 2011

There is growing evidence that alfalfa (Medicago sativa L. sensu lato) germplasms that perform well in trials that are mechanically clipped may not persist well under grazing. This trial assessed the persistence of nine alfalfa germplasms under grazing over a period of 4 yr in northeast Saskatchewan. The germplasms included registered cultivars and experimental strains of M. sativa ssp. media Pers. and M. sativa ssp. falcata (L.) Arcang. with a range of growth habits and winterhardiness. Each paddock was seeded with all entries in mixture with smooth bromegrass (Bromus inermis Leyss.) and grazed repeatedly for 1- to 2-d periods, using high stocking rates, to ensure that all entries were grazed uniformly. Three grazing intensities — light, moderate and intense — were set by varying the rest period between grazings. Ground cover of all the currently recommended alfalfa cultivars of the media ssp. declined during the trial; the germplasms of falcata ssp. increased; and two media ssp. strains from northern Alberta maintained fairly constant ground cover. Grazing intensity affected rate of stand decline but not final ranking of germplasms, so there was no grazing × germplasm interaction. Seeded and volunteer smooth bromegrass maintained better stands under light than intense grazing, whereas volunteer bluegrass (Poa spp.) performed better under intense grazing. Ground cover of alfalfa germplasms was generally correlated with their annual yield and proportion of total dry matter yield. The results suggest that falcata germplasms should be included in seed mixes for long-term pastures and that mob grazing be used to assess the persistence of alfalfa germplasms before they are recommended for use in pastures. Key words:Medicago sativa L., Medicago sativa ssp. falcata (L.) Arcang., persistence, grazing tolerance.
Herbage production as influenced by stand arrangement, nitrogen fertility and supplemental water
Authors: Fairey N. A. , Lefkovitch L. P.
Published: April 2011

Nitrogen (N) fertilizer is usually applied to grass-legume herbage stands at a rate representing a compromise between the low N tolerance of the N-fixing process of legumes and the high N requirement of grasses. The productivity and N responsiveness of a bromegrass-alfalfa association was compared for stands in which the components were arranged at random (conventional grass-legume mixture, GLM) with those in adjacent, 1.5-m-wide strips of grass and legume (strip-culture, SC). One experiment compared three stand arrangements (GLM, and SC stands with grass:legume land areas of 1:1 and 2:1) receiving two rates of supplemental N (0 and 60 kg ha−1 N). A second experiment compared GLM to the 1:1 SC stand at five rates of supplemental N (0, 40, 80, 120, and 160 kg ha−1 N restricted to grass-containing areas of each stand treatment) under both natural and supplemental soil-moisture conditions. Physically separating the grass and legume plants in the SC stands reduced total herbage dry matter (DM) yield, particularly when little or no N was applied. In the SC stands, the reduction in DM yield caused by physically separating the grass and legume plants of the herbage mixture was compensated for by an increase in the apparent efficiency of N fertilizer use by the grass plants in that association. Herbage DM yield was enhanced greatly by supplemental water but the effects of N fertilization and/or stand arrangement were not modified by soil-moisture conditions. Strip-culture stands facilitate independent optimization of inputs for components of grass-legume associations. Key words: Grass-legume mixtures, nitrogen response, stand arrangement, herbage production, irrigation, bromegrass-alfalfa
AC Kingston red clover
Authors: Choo T. M. , Christie B. R.
Published: April 2011

AC Kingston red clover (Trifolium pratense L.) is a diploid cultivar of the double-cut type developed by mass selection at the Agriculture Canada Research Station, Charlottetown, PEL It is similar to Florex in maturity, but is superior in forage yield in the second harvest year. It was selected for persistence under field conditions. Key words: Red clover, Trifolium pratense L., persistence, cultivar description
Downy brome (Bromus tectorum) control in winter wheat and winter rye
Authors: Blackshaw R. E.
Published: April 2011

Field studies were conducted over 4 yr to identify herbicides for selective control of downy brome in winter wheat (Triticum aestivum L.) and winter rye (Secale cereale L.). Cinmethylin, diclofop, and napropamide did not control downy brome in any year. BAY SMY 1500 applied pre-emergence or early postemergence at 1.5–2.0 kg ha−1 controlled downy brome and increased the yield of winter wheat. However, BAY SMY 1500 treatments often reduced the growth and yield of winter rye. Metribuzin applied early postemergence at 0.42 kg ha−1 effectively controlled downy brome and increased the yield of both winter wheat and winter rye. Metribuzin applied at 0.42–0.56 kg ha−1 pre-emergence on a coarse-textured soil with 2% organic matter injured winter wheat and reduced yield. Key words:Bromus tectorum L., cinmethylin, diclofop, BAY SMY 1500, metribuzin, napropamide
Quackgrass suppression through crop rotation in conservation tillage systems
Authors: Loeppky H. A. , Derksen D. A.
Published: April 2011

Quackgrass [Elytrigia repens (L.) Nevski] is a widespread perennial weed traditionally controlled by tillage, a practice which can contribute to soil erosion and degradation. This study was initiated to determine the impact of integrated weed management strategies utilizing crop rotation, conservation tillage, and postemergence herbicides on quackgrass. Rotations of tall and semi-dwarf winter wheat (Triticum aestivum L. 'Norstar' and 'Norwin') or spring wheat (Triticum aestivum L. 'Katepwa' and 'HY320') with mustard (Brassica juncea 'Common Brown') and flax (Linum usitatissimum L. 'Norlin') were conducted at Indian Head, Saskatchewan for 4 yr to determine their effect on quackgrass shoot density, rhizome dry weight and rhizome node density. The presence or absence of winter wheat within the crop rotation had the greatest impact on quackgrass growth. During years when drought hampered winter wheat establishment, quackgrass growth was greater in winter wheat than in spring wheat, but under conditions favoring winter wheat establishment, the opposite occurred. Quackgrass growth in standard height wheat was similar to semi-dwarf wheat. Annual differences in quackgrass growth occurred between mustard and flax, but overall, no trend developed. Shoot density, rhizome biomass, and rhizome node density were not consistently correlated to crop yield. Crop rotation is a useful component of an integrated quackgrass management system. Key words: Integrated weed management (IWM), quackgrass, Elytrigia repens, crop rotation, conservation tillage
Row spacing and seeding rates to optimize safflower yield on the Canadian prairies
Authors: Mündel H.-H. , Morrison R. J. , Entz T. , Blackshaw R. E. , Roth B. T. , Kiehn F. , Vandenberg A.
Published: April 2011

Nine experiments were conducted in Alberta and Manitoba between 1988 and 1991 to determine the effect of row spacing and seeding rates on safflower (Carthamus tinctorius L.) yield, oil content, test weight and maturity. Row spacings of 15 and 30 cm at Morden had little effect on yield, while in southern Alberta there was a tendency toward increased yields with narrow rows (23 cm) compared with wide rows (46 cm). Seeding rates of 32–40 kg ha−1 were required to obtain maximum seed yields. Oil content, test weight, and days to maturity were not consistently affected by row spacing or seeding rate. Key words:Carthamus, row spacings, seeding rates, yield, oil, test weight, maturity
Novel trichomes increase stamen stiffness in mung bean flowers
Authors: Liptay A. , Vandierendonck P. , Liptay A. M. J.
Published: April 2011

The exterior of the cylindrical stamens of mung bean [Vigna radiata (L.) Wilczek] flowers are replete with trichomes attached at both ends to the outside periphery of the stamen. The resultant repetitive pattern from below the base of the stamen to the anther resembles a multi-stranded rope configuration. Tests on models with or without simulated doubly attached, trichome-like structures, indicated about a 12-fold increase in stiffness with addition of the trichome-like structures. It is hypothesized that the function of the trichomes on the stamens is to increase their rigidity to ensure successful pollen transfer from the anther as the stigma elongates past the anther. In contrast to the trichomes on the stamen, those on the surface of the style are like a coarse-haired brush apparently designed to collect pollen as the stigma extends past the anthers. Key words: structural strength, stiffness, Vigna radiata
Influence of N supply on development and dry matter accumulation of an old and a new maize hybrid
Authors: McCullough D. E. , Mihajlovic M. , Aguilera A. , Tollenaar M. , Girardin Ph.
Published: April 2011

The response of an old and a new maize (Zea mays L.) hybrid to N supply was evaluated under controlled-environment conditions. An old hybrid (Pride 5) and a new hybrid (Pioneer 3902) were grown at three N levels (15, 2.5, and 0.5 mM N), and development and dry matter accumulation were measured at the 4-, 8-, and 12-leaf stage. Leaf chlorophyll was monitored from the 8- to 12-leaf stage, and leaf photosynthesis, stomatal conductance, and leaf chlorophyll fluorescence were measured at the 12-leaf stage. Rate of dry matter accumulation decreased with declining N supply. In contrast, decreasing N supply progressively increased the duration of the 4- to 8-leaf phase and the 8- to 12-leaf phase. As a consequence, total dry matter at the 12-leaf stage did not differ among N levels. The rate of leaf appearance of the old hybrid (Pride 5) was proportionately more reduced under low N than that of the new hybrid (Pioneer 3902). Similarly, the reduction in crop growth rate during the 8- to 12-leaf stage at the lowest N level was 46% for Pride 5 and 24% for Pioneer 3902. Leaf chlorophyll content was higher for Pride 5 than for Pioneer 3902 at high N levels, but leaf chlorophyll content declined significantly more rapidly in Pride 5 than in Pioneer 3902 when N stress increased. Leaf carbon assimilation rates were 4–27% higher for the new hybrid, with the largest differences occurring at low N levels. Collectively, results of this study show that the old hybrid (Pride 5) was more sensitive to N stress during early development than the new hybrid (Pioneer 3902). Key words:Zea mays L., nitrogen stress tolerance, chlorophyll content, photosynthesis, chlorophyll fluorescence
Corn kernel breakage as a function of grain moisture at harvest in a prairie environment
Authors: Plett S.
Published: April 2011

The relationship between grain moisture at harvest and the amount of kernel cracking was evaluated at Brandon, Manitoba. Grain moisture at harvest was closely correlated to percentage kernel cracking. Least amount of kernel cracking occurred with grain moisture ranging from 16.7% for K730 to 22.1% for 3979. Key words: Maize, kernel breakage, grain moisture
Effect of zinc on cadmium concentration in the tissue of durum wheat
Authors: Choudhary M. , Bailey L D. , Grant C. A.
Published: April 2011

The addition of zinc at 20 mg kg−1 to soils in a growth chamber study reduced the shoot Cd concentration of two durum wheat (Triticum turgidum L. var durum) lines at 10 °C, 16 °C, and 22 °C soil temperatures while additions of ammonium nitrate (NH4NO3) and monoammonium phosphate (NH4H2PO4) increased shoot Cd concentrations. Applying Zn with NH4NO3 or NH4H2PO4 reduced shoot Cd concentrations of the plants to levels comparable to the control. Key words: Cd, durum wheat, ammonium nitrate, monoammonium phosphate, Zn
AC Splendor orchardgrass (Dactylis glomerata L)
Authors: McElroy A. R.
Published: April 2011

AC Splendor is a late-maturing orchardgrass (Dactylis glomerata L.) cultivar. It was developed by phenotypic selection within cv. Rideau for winter hardiness, yield, persistence and absence of stem rust (Puccinia graminis) at the Plant Research Centre. Agriculture and Agri-Food Canada, Ottawa. Its forage yield was 103.2% of cv. Kay over 15 station years in Ontario. Yield in second and subsequent production years was 101.7% of cv. Kay over 8 station years. Key words:Dactylis glomerata L., orchardgrass
Increasing sampling efficiency of lowbush blueberries
Authors: Nams V. O.
Published: April 2011

Yield estimates of lowbush blueberries (Vaccinium angustifolium Ait.) are highly variable. Two techniques for estimating cover, and five quadrat sizes for estimating stem density were tested in an attempt to minimize this variability. The most efficient technique for estimating cover is pacing for 100 footsteps and counting the number of footsteps falling within blueberry patches. The most efficient quadrat size for estimating stem density within blueberry patches is 0.025 m2. Variability attributable to observers accounted for 23% of the variance in stem density estimates, but this decreased to 4% with a short training session at the start of each field and sampling day. Key words: Blueberries, Vaccinium angustifolium, sampling, quadrat, cover estimates, stem densities
Resistance to barley yellow dwarf luteovirus in Aegilops species
Authors: Makkouk K. M. , Ghulam W. , Comeau A.
Published: April 2011

One thousand and ninety-seven Aegilops accessions were evaluated for their reaction to a PAV serotype of barley yellow dwarf luteovirus (BYDV). The accessions tested belong to the species bicornis, biuncialis, caudata, crassa, columnaris, comosa, cylindrica, kotschyi, longissima, mutica, neglecta (= triaristata 4 ×), ovata, peregrina, searsii, sharonensis, speltoides, tauschii (= squarrosa), triuncialis, umbellulata, uniaristata, vavilovii and ventricosa. The first evaluation of virus levels in the different accessions was conducted at International Center for Agricultural Research in the Dry Areas (ICARDA), Aleppo, Syria, using double antibody sandwich ELISA (DAS-ELISA). Accession reaction ranged from highly resistant to highly susceptible. Thirty-eight Aegilops accessions resistant at ICARDA, were evaluated at Sainte-Foy, Quebec, Canada, by tissue-blot immunoassay. Diversity of response to BYDV infection was again observed in this elite group. Seven accessions belonging to the species biuncialis, caudata, neglecta and triuncialis were highly BYDV resistant at both locations; five of these originated from Bulgaria. Key words: Introgression, interspecific, Triticum aestivum, BYDV, ELISA, immunoassay, tissue blot
Response of four quackgrass (Elytrigia repens (L) Nevski) biotypes to desiccation
Authors: Reidy M. E. , Swanton C. J.
Published: April 2011

The response of four quackgrass biotypes to desiccation was investigated. Rhizomes from field populations of each biotype were harvested at four predetermined dates over 1 yr. At each harvest date, rhizomes were transferred to the laboratory and subjected to four levels of desiccation. Desiccated rhizomes harvested in November and June regenerated significantly more shoots than those harvested in May and July. At 60% desiccation, regeneration ranged from 63 to 93%, depending upon the biotype. The lowest regeneration occurred with the Manitoba biotype, M7, harvested in May or July. The Quebec and Ontario biotypes had at least 87% regeneration at each harvest date. Key words:Elytrigia repens, quackgrass, biotypes, desiccation tolerance, weed control
Evaluation of barley cultivars for resistance to ergot fungus, Claviceps purpurea (Fr.) Tul.
Authors: Pageau D. , Wauthy J.-M. , Collin J.
Published: April 2011

From 1988–1990, entries of a barley (Hordeum vulgare L.) adaptation test were evaluated under conditions of natural infection for resistance to the ergot fungus (Claviceps purpurea L. (Fr.) Tul.). The study was conducted at four sites in the Lac-St-Jean region of Quebec, Canada, where the disease is endemic. Cultivars Laurier (3-yr test), Maskot and Sabina (2-yr test) were the most resistant with sclerotial content below 0.10%. Cultivars Albany and Leger (3-yr test), Symko and Morrison (2-yr test) were the most susceptible. Results indicate there is genetic variability for ergot resistance in barley. This resistance may be useful in control of ergot under conditions of natural infection. Key words: Barley, ergot, resistance
Ranking wheat cultivars for test weight based on small grain samples
Authors: Thomas Julian B.
Published: April 2011

Although test weight is highly heritable in wheat (Triticum aestivum L. em. Thell.), selection for this important trait is limited in the early generations of a breeding program by the availability of seed. In winter wheat, the weight of seed discharged by the Balfour Seed Dispenser or BSD was highly correlated (r = 0.97 to 0.99) with test weight measured using the Dickey John Grain Analysis Computer. The BSD required less labour and less sample (25–80 g) than either the GAC II or Cox Funnel drop methods (300–1000 g) but was also less accurate. Nonetheless the lower confidence interval (P < 0.025) of a measurement on the BSD was only about −0.75% which is equivalent to a negative deviation of about 0.6 kg hL−1. This degree of accuracy should identify most lines of wheat with low test weight in any breeding program. Key words: Breeding, bulk density, bushel weight, selection
Genetic variation and adaptation of 76 Canadian barley cultivars
Authors: Kong D. , Choo T. M. , Narasimhalu P. , Jui P. , Ferguson T. , Therrien M. C. , Ho K. M. , May K. W.
Published: April 2011

A study was initiated in 1990 to determine the genetic variation and adaptation of all registered Canadian barley (Hordeum vulgare L.) cultivars. Seventy-six cultivars were tested at four locations across Canada (Charlottetown, Ottawa, Brandon, and Bentley) in 1991 and 1992. These cultivars were grouped into 10 classes and classes were compared in five categories: eastern vs. western, doubled-haploid (DH) vs. conventional, feed vs. malting, two-row vs. six-row, and hulless vs. covered. These 76 cultivars showed remarkable variation in yield, test weight, kernel weight, plant height, and maturity and responded differently to the environments. Among them, Albany and Chapais had the highest yield and they also yielded well in both Eastern and Western Canada. Thus, some barley cultivars were widely adapted across the whole country. Two-row cultivars had higher test weight and higher kernel weight than six-row and appeared to be more stable in yield over the environments. Eastern two-row cultivars were superior in yield, test weight, and kernel weight than western two-row. Eastern two-row, in general, performed well across Canada. Several western six-row cultivars performed well in both Western and Eastern Canada. Therefore, greater exchanges of breeding materials between the two regions are recommended in order to fully exploit the genetic potentials of new cultivars. DH cultivars yielded as well as conventional cultivars and responded similarly to the environments. This substantiates that complete homozygosity and homogeneity have very little effect on the performance of DH cultivars. Among the western two-row, feed cultivars yielded either higher than or the same as malting cultivars in the eight environments. Hulless cultivars had lower yield, higher test weight and lower kernel weight than covered cultivars. Key words: Barley, Hordeum vulgare, cultivar, yield, adaptation
Selecting stable and high-yielding sorghum cultivars for the semi-arid tropics
Authors: Dangi O. P. , Hamilton R. I. , Lin C. S. , Andre D. , Johnson J. J.
Published: April 2011

A sorghum breeding program was reactivated in 1981 and selected cultivars, along with local checks, were evaluated in two experiments in the sorghum growing region of northern Cameroon. Experiment 1 was conducted in the Extreme North Province where annual rainfall ranges from 450 to 850 mm. Experiment 2 was conducted in the North Province where annual rainfall exceeds 850 mm. The objective of the study was to select a high yield and high stability sorghum cultivar for each region. The cultivar's responses were investigated using two analyses: the adaptability analysis and the stability analysis. The former used the method of superiority measure, defined by distance mean square between the test cultivar and the maximum (the highest yield in the location), and the latter used type 4 stability parameter, defined by the years within location mean square averaged over all locations. The conceptual separation of adaptability and stability facilitated the cultivars assessment. The results showed that in exp. 1, three cultivars S–35, CS–54 and CS–61 had similar adaptability and stability, while in the exp. 2, S–34 was best in terms of yield but was unstable due to susceptibility to grain mold. In contrast, the second best cultivar CS–63 was poorer in the high-yielding environments but was more stable than S–34. Key words: Sorghum, genotype-environment interaction, adaptability, stability parameters
Response of sunflower plants to physical injury
Authors: Schneiter A. A. , Johnson B. L.
Published: April 2011

Injury to sunflower (Helianthus annuus L.) caused by hail and pests can result in financial losses to producers. This field study was conducted to determine the response of sunflower to different types and levels of physical injury. The information will assist producers in deciding whether to replant or maintain a crop. Studies were conducted at four North Dakota locations. Treatments consisted of stand reduction, terminal bud removal, and top one third of the plant cut off, imposed on either 25 or 50% of an established plant population at five stages of plant development. Plant response to injury varied among treatment stages. When plants were injured at vegetative stages V4 and V8, 98.2 and 93.2% of the treated plants produced multiple branches and heads. When plants were injured during the transition from vegetative to reproductive development (V12, R1), a greater proportion (26.1 and 20.6%, respectively) of the plants died. The majority of the plants injured at stages R1 and R3 neither died nor branched (55.5 and 96.1%, respectively); they continued to live but did not produce seed. Living injured plants reduced total crop yield more than the injured plants that died, since living injured plants continued to compete with uninjured plants for space, light, nutrients and moisture but did not contribute toward yield. Key words: Sunflower, Helianthus annuus L., hail, crop injury
Evaluation of sainfoin-alfalfa mixtures for forage production and compatibility at a semi-arid location in southern Saskatchewan
Authors: Kielly G. A. , Jefferson P. G. , Lawrence T. , Irvine R. B.
Published: April 2011

Alfalfa (Medicago sativa L.) is an adapted pasture legume for the semi-arid region of western Canada but its use is restricted because of ruminant bloat hazard. Sainfoin (Onobrychis viciifolia Scop.) is a non-bloat-inducing forage legume that yields less forage than alfalfa in this region. Mixture of these legumes may mitigate respective weaknesses by combining their strengths. The objective of this research was to determine the stability of seed-mixture (two legumes seeded in the same row) compared to legume monoculture and alternate row seeding (two legumes seeded in separate but adjacent rows). Three trials were seeded on dryland sites at Swift Current, Saskatchewan, in 1977, 1986, and 1987. Treatments varied from the first trial to the last three but all trials allowed comparison of seed-mixture seeding to monoculture and alternate row swards. In the first and second trials, seed-mixture species composition shifted to alfalfa domination (> 90% alfalfa) over 5 yr more quickly than alternate row, presumably due to interspecific competition. In the other trial, seed-mixture was dominated by alfalfa within 2 yr after seeding due to drought stress. We concluded that sainfoin-alfalfa mixtures are not stable or sustainable in this semi-arid environment. Key words: Competition, ruminant bloat, onobrychis, seeding pattern
Rendement potentiel en semence l'année du semis de cultivars de trèfle rouge
Authors: Belzile Lucius
Published: April 2011

The potential of seed production of red clover (Trifolium pratense L.) in the seeding year was studied for 4 yr using five cultivars on two soil types. Data were collected on seed yield, weight and germination. Yields of up to 580 kg ha−1 were obtained. Interactions of the effects of soil, year and cultivar on seed yield were observed. The absence of a dominant effect on seed yield is probably related to the varying moisture conditions among years and the age diversity of the plant population from which seeds were harvested. Seed germination varied among years and cultivars and seed weight among cultivars. Key words: Red clover, seed production, cultivar, seeding year
AC Copia spring triticale
Authors: McLeod J. G. , DePauw R. M. , Clarke J. M. , Townley-Smith T. F.
Published: April 2011

AC Copia, a cultivar of spring triticale (X Triticosecale Wittmack), was developed at the Research Station, Research Branch, Agriculture and Agri-Food Canada, Swift Current, SK. It is widely adapted to the Prairie Provinces of Western Canada. AC Copia represents an improvement in test weight over other currently available Canadian cultivars of triticale. It is very resistant to the prevalent races of leaf rust, stem rust and common bunt, and moderately resistant to common root rot. Key words: Cultivar description, test weight, triticale (spring), X Triticosecale Wittmack
Comparison of time and depth of last tillage on the growth of Canada thistle (Cirsium arvense) in summerfallow and its response to glyphosate
Authors: Darwent A. L. , Townley-Smith L. , Lefkovitch L. P.
Published: April 2011

Field studies were conducted in summerfallow in 1990 and 1991 at Bezanson, Alberta (lat. 55°14′N, long. 118°22′W), and Melfort, Saskatchewan (lat. 52°52′N, long. 104°36′W), to compare the development of Canada thistle [Cirsium arvense (L.) Scop.] shoots following the discontinuance of normal tillage at three times (19 July, 30–31 July and 9–12 Aug.), at three depths (0, 10 and 20 cm), and its response to glyphosate applied at 0.9 kg ha−1 40 d after the last tillage (DALT). The tillage treatments had no consistent effect on shoot density when measured at 40 DALT at either location. At Bezanson, small increases (< 5%) in shoot density occurred between 20 and 40 DALT where tillage was conducted at the shallowest depth, but increases of approximately 20–90% occurred during the same period following tillage at the 10 or 20-cm depth. The proportion of emerged shoots remaining as rosettes at 40 DALT increased as the time of discontinuing tillage was delayed. At Bezanson, the proportion of emerged shoots remaining as rosettes at 40 DALT increased from 0.17 ± 0.05 to 0.59 ± 0.02 when the time of discontinuing tillage was delayed from mid-July to early August, while at Melfort an increase from 0.47 ± 0.04 to 0.93 ± 0.02 occurred for a similar delay in time of discontinuing tillage. Increasing the depth of last tillage increased the proportion of emerged shoots remaining as rosettes at 40 DALT at Bezanson, but at Melfort the depth of last tillage had no effect on this proportion. The proportion of shoots remaining as rosettes declined between 20 and 40 DALT when measured at Bezanson. Factors causing an increase in the proportion of shoots remaining as rosettes appeared to be associated with exposure of emerged shoots to reduced daylengths. At both Bezanson and Melfort, shoot density measured 1 yr after tillage–glyphosate treatments was similar in all plots. Thus, the proportion of shoots remaining as rosettes at the time of glyphosate application did not appear to influence the response of Canada thistle to the herbicide. Key words: Integrated weed control, daylength, rosette, perennial-weed control
A History of the Canadian Pest Management Society
Authors: Holm F. A. , Scott J. A. , Ivany J. A.
Published: April 2011

not available
Crop diversification in Canada with particular reference to genetic resources
Authors: Small Ernest
Published: April 2011

This review examines crop diversification in Canada and some principal related issues, particularly type of crop and genetic resources. Crop diversification is frequently achieved through the adaptation of established crops to new production areas or through new uses of plant constituents of well-known crops. With such crops there is reasonable probability of success because of established markets and the availability of already-developed germplasm, which can be further improved. By contrast, crops that appear to require costly, long-term breeding and market investment are considered economically risky, and there is limited incentive to develop the necessary genetic resources for their improvement. However, some undeveloped crops may offer sufficient potential to warrant the risk. Criteria need to be formulated for crop-diversification candidates in a country, particularly for those in which investment in genetic resources is warranted. In Canada, competitive advantages with respect to cultivation and market factors should be considered. On the basis of these and other considerations, priority would seem to be justified for some native forages, native fruits, biomass crops, wild rice, and greenhouse herbs. Priority should be explored for other plants, notably industrial and pharmaceutical crops, fiber plants, and ornamentals. Key words: Genetic resources, germplasm, crop diversification
Inheritance of resistance to diclofop-methyl and fenoxaprop-p-ethyl in two Avena sativa × A. fatua populations
Authors: Kibite Solomon , Harker K. N. , Brown P. D.
Published: April 2011

Since the late 1980s, several reports of herbicide-resistant wild oat have raised concern about potential weed control problems in western Canada. This study was conducted to determine the mode of inheritance, number of genes and type of gene action governing herbicide resistance in two Avena sativa × A. fatua crosses. The herbicide-susceptible A. sativa cultivars, Random and Derby, were crossed with a resistant A. fatua genotype, GP-HR-01. Parents, F2s and F2:3 families were tested for their reactions to two post-emergent wild oat herbicides, diclofop-methyl and fenoxaprop-p-ethyl, in the greenhouse. Inheritance of resistance to diclofop-methyl and fenoxaprop-p-ethyl was dominant and monogenic in the Derby/GP-HR-01 cross, but was controlled by two dominant complementary genes in the Random/GP-HR-01 cross. Resistance to both herbicides appeared to be controlled by the same genes or groups of tightly linked genes. Key words:Avena sativa, Avena fatua, herbicide resistance, weed (genetics), diclofop-methyl, fenoxaprop-p-ethyl
Plant population and hybrid considerations for dryland corn production on drought-susceptible soils
Authors: Miller L. C. , Vasilas B. L. , Taylor R. W. , Evans T. A. , Gempesaw C. M.
Published: April 2011

Selection of a target population for dryland corn (Zea mays) production on drought-susceptible soils is a difficult decision, as a stand appropriate for drought conditions may not fully utilize the environment during a non-stress year. One possible management strategy is to use a low seeding rate and hybrids with ear characteristics that promote yield stability over a range of environments and plant populations. To evaluate this strategy, a 2-yr field study was conducted on a Rumford loamy sand. The performance of four hybrids — 1) full season, flexible ear; 2) short season, flexible ear; 3) full season, prolific; and 4) short season, prolific — was evaluated at four populations — 29 600, 39 500, 49 400, and 59 300 plants ha−1 — in two different growing seasons. Seasonal precipitation in 1988 was 14 cm below the average of 50 cm; 1989 seasonal precipitation was 37 cm above average. Average grain yields were 40% lower in 1988 than in 1989, and the yield loss was due primarily to a decrease in ear size. All hybrids demonstrated the ability to compensate for changes in population in 1988. Averaged across years, highest yields were produced with the two highest populations. The full-season, prolific hybrid was the most productive at every population. Key words: Maize, Zea mays, genotype × environment interactions, plant population, prolificacy, ear size
Polymorphism of oat kernel size and shape in several Canadian oat cultivars
Authors: Pietrzak L. N. , Fulcher R. G.
Published: April 2011

This study used digital image analysis to quantify variation of morphological characteristics of oat kernels. Ten Canadian oat varieties grown in 1984 and 1985 at five and four locations, respectively, were examined. Statistically significant differences in polymorphism among varieties collected from the same location were observed. It appeared that the genetic diversity of all analyzed varieties is quite high, and results from a broad range of kernel sizes are evenly distributed within population. The environment has little effect on the polymorphism of seed shape. The same varieties grown in different locations appeared to have almost the same diversity index, and the aspect ratio (AR) depends primarily on the genetic structure of the population. However, the diversity index of AR for each variety calculated over all locations appeared to be almost the same. Key words: Oat, Avena sativa, digital image analysis, size and shape
Companion crop, herbicide and weed effects on establishment and yields of alfalfa-bromegrass mixture
Authors: Moyer J. R. , Cole D. E. , Maurice D. C. , Darwent A. L.
Published: April 2011

Alfalfa (Medicago sativa L.) and bromegrass (Bromus spp.) were seeded with and without a companion crop and with and without herbicides at Westlock and Lethbridge, Alberta, to assess the effect of weed control, companion crop and the herbicide-by-companion crop interaction on forage establishment and subsequent yields. A companion crop reduced both alfalfa and bromegrass yields for at least 2 yr after establishment on a rain fed site at Westlock and for 1 yr after establishment on an irrigated site at Lethbridge. At both sites, weed yields were higher after establishment with a companion crop than after establishment without a companion crop. Unchecked weeds in the establishment year had less effect than a companion crop on subsequent forage yields. At both locations, weed biomass in the establishment year was less than that of the companion crop. The combined stress of a companion crop and 2,4-DB application had a detrimental effect on alfalfa yield for 3 yr after establishment at Lethbridge. Key words: Wheat, barley, wild oat, redroot pigweed, dandelion
Phenylalanine ammonia lyase as a precursory enzyme of legume stem lignification
Authors: Bidlack J. E. , Buxton D. R. , Shibles R. M. , Anderson I. C.
Published: April 2011

In some instances, lignin content may not be significantly correlated with phenylalanine ammonia lyase (PAL) activity because: (1) PAL is not committed exclusively to lignin, and (2) the time of maximum PAL activity may not coincide with maximum lignin deposition. This study evaluates correlations and timing of PAL activity and lignin deposition during legume stem maturation. Three forage legumes, alfalfa (Medicago sativa L.), birdsfoot trefoil (Lotus corniculatus L.), and red clover (Trifolium pratense L.), were established, and basal stem regrowth was sampled, biweekly, for 10 wk, for dry weight (DW), cell wall (CW), lignin, and PAL analyses. Nonlinear regression of lignin content by the Gompertz function indicated that lignin increased sigmoidally, and PAL activity by the third-order quadratic demonstrated rapid initial increases in activity, followed by decreases, as a function of regrowth days. First derivative of the Gompertz function demonstrated that changes in lignin deposition closely resembled changes in PAL activity. Among species, peak deposition of DW and CW content occurred 3–11 d prior to maximum lignin deposition. Time of maximum PAL activity occurred 8 d prior to maximum lignin deposition in birdsfoot trefoil and red clover and 3 days after maximum lignin deposition in alfalfa. Across species, lignin content was not positively correlated with PAL activity on a protein basis. However, lignin deposition was positively correlated with PAL per unit protein (r = 0.76, P < 0.05) and lignin content was positively correlated with PAL on a per plant basis (r = 0.60, P < 0.05). These results indicate that the activity of PAL is related to lignin deposition in a cause-and-effect relationship. Key words: Alfalfa, birdsfoot trefoil, cell wall, lignin, phenylalanine, ammonia lyase, red clover
Selection for resistance to root rot caused by Fusarium spp. in red clover (Trifolium pratense L.)
Authors: Coulman B. E. , Lambert M.
Published: April 2011

Root and crown rots caused by Fusarium spp. are a major cause of stand decline of red clover (Trifolium pratense L.) in North America. The goal of this study was to evaluate the effectiveness of one cycle of selection for resistance to Fusarium root rot. Plants of the red clover cultivars Florex and Arlington were screened for their resistance to infection by two isolates of Fusarium acuminatum and one isolate of F. avenaceum. Plants of various infection categories were intercrossed, and progenies were screened to estimate the heritability of resistance to these pathogens. Synthetics produced by intercrossing either highly resistant (R) or highly susceptible plants were evaluated under sward conditions in the field for dry matter yield, root rot and adventitious root development. There were significant (P = 0.05) differences in aggressiveness among the three Fusarium isolates used, with F. avenaceum 814 being the most aggressive. Plants classed as R for all three isolates were found in both cultivars; however, disease reaction was not always correlated among the isolates. Parent-progeny regressions or correlations of disease reaction were negative in the cultivar Arlington, while for Florex, a relatively low regression coefficient of 0.26 was found. In the field evaluation in the fall of the third year after seeding, synthetics of plants selected for resistance were either not different from, or higher in infection score than the parental cultivars, indicating that selection using one or two isolates/species was ineffective in improving field root rot resistance. Plants with more severely rotted roots showed a tendency to produce more adventitious roots from the crown. It was concluded that progeny testing would be necessary for selection to be effective for resistance to Fusarium root rot in red clover and that more that one isolate or species of the fungus should be used in screening programs. In addition, not all populations of red clover contain sufficient genetic variation for resistance to justify a selection program. Key words: Red clover, disease resistance, selection, root rot, adventitious roots, Trifolium pratense L., Fusarium spp.
Quantifying the nonlinearity in chlorophyll meter response to corn leaf nitrogen concentration
Authors: Dwyer L. M. , Stewart D. W. , Gregorich E. , Anderson A. M. , Ma B. L. , Tollenaar M.
Published: April 2011

Chlorophyll meters have been used to provide a rapid non-destructive method to estimate corn leaf nitrogen (N) concentration, although meter readings plateau at high leaf N levels. Paired chlorophyll meter and leaf N concentration data were obtained for ear level leaves at growth stages ranging from 3 wk before anthesis to 5 wk after anthesis over a 2-yr period at Ottawa, Ontario. Separate quadratic-plus-plateau models best represented chlorophyll meter response to leaf N concentration for pre-anthesis, early grain-fill and late grain-fill stages; chlorophyll meter readings corresponding to the beginning of the plateau increased at later growth stages. Leaf N concentration was estimated well from chlorophyll meter readings up to the plateau range using growth stage specific functions (R2 ≥ 0.77) but chlorophyll meter readings beyond the plateau should not be used to estimate leaf N concentration. Key words: Chlorophyll meter calibration, maize