bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECTS OF 25 YEARS OF N, P AND K FERTILIZATION ON YIELD, PERSISTENCE AND NUTRITIVE VALUE OF A TIMOTHY SWARD
Authors: BÉLANGER G. , RICHARDS J. E. , WALTON R. B.
Published: March 2010

The effects of over 25 yr of levels of applied N, P and K on forage DM yield, crude protein content, in vitro digestibility (IVD), botanical composition and persistence of a timothy (Phleum pratense L.) sward were assessed in a long-term field experiment on an acidic Riverbank L. Ammonium nitrate (0, 90, 180, 270 kg N ha−1), superphosphate (0, 15, 29, 44 kg P ha−1) and muriate of potash (0, 47, 94, 141 kg K ha−1) were applied annually in all possible combinations to a timothy sward since 1960. In the first 3 yr of the experiment, only N and K were required for maximum yield and persistence of timothy. The requirement for applied P, however, increased with time; in the last 3 yr (1985–1987) of the trial, the highest level of applied P resulted in profitable forage DM yield increases. After 25 yr, the productivity of the timothy sward was dependent upon a balanced application of all three macronutrients; absence of any one nutrient resulted in little or no response to applications of the other nutrients. The long-term persistence of timothy was solely dependent on K fertilization. The proportion of bentgrass and bluegrass species declined with increasing levels of applied K while that of timothy increased. The change in botanical composition due to applied N and K significantly affected IVD and crude protein content.Key words: N, P, K, fertilization, yield, persistence, timothy
EFFECTS OF SUPPLEMENTAL LIGHTING AND ROOT-ZONE TEMPERATURE ON GROWTH OF CHRYSANTHEMUMS IN NUTRIENT FILM
Authors: HICKLENTON PETER R.
Published: March 2010

Winter (8 Nov. – 16 Jan) and spring (28 Feb. – 8 May) crops of Chrysanthemum morifolium ’Polaris’ were grown in nutrient film culture in greenhouses. Supplemental high pressure sodium lighting (80 μmol s−1 m−2) was provided to half the plants in each crop during the first 21 d of growth while root zone temperature (RZT) was maintained at either 12, 20 or 28 °C for the duration of the production period. Root and shoot dry weights and leaf area were increased by supplemental lighting when measured at the end of the vegetative growth stage (14 long days). At maturity, flower and vegetative dry weight, stem length, leaf area and flower number were increased by early supplemental lighting. For stem length and flower dry weight the beneficial effects were greater for the winter crop. Leaf area and root dry weight were reduced at 12 °C RZT, particularly under supplemental lighting. Flower buds were formed more rapidly on plants grown under supplemental lighting and for those grown at 20 or 28 °C RZT. Increasing RZT from 12 to 20 °C was generally more beneficial than an increase from 20 to 28 °C for both vegetative and flower traits.Key words: Chrysanthemum morifolium, irradiance, solution culture, hydrophonics, cut flowers
EFFECT OF ALDICARB, ALDOXYCARB AND OXAMYL ON POTATO TUBER YIELDS AND ROOT LESION NEMATODES
Authors: KIMPINSKI J. , SANDERSON J. B.
Published: March 2010

In a 3-yr field study at Upton, Prince Edward Island, aldicarb at 1.12 and 2.24 kg a.i. ha−1 and oxamyl at 2.24 kg a.i. ha−1 were applied in the furrow with seed potatoes. Nematicide treatments increased tuber yields of Superior by 15.5% (4.6 t ha−1) and yields of Russet Burbank by 9.3% (3.4 t ha−1). Shepody did not respond to nematicide treatments. The effect of aldicarb on average yields of all three cultivars did not differ from that of oxamyl, nor did yields at the higher rate of aldicarb differ from those at the lower rate. In a two-year field study at Harrington, Prince Edward Island, aldicarb and aldoxycarb applied at a rate of 2.24 kg a.i. ha−1 increased yields of Superior by similar amounts of about 40% (9.4 t ha−1). Oxamyl applied at the same rate in the second year had the same impact on yields as aldicarb or aldoxycarb. Nematicide treatments reduced the numbers of root lesion nematodes (primarily Pratylenchus penetrans) in roots and soil at Upton. Both rates of aldicarb had a similar impact, but oxamyl was less effective than the aldicarb treatments in reducing nematode numbers in roots. At Harrington, aldicarb controlled nematode populations more efficiently than aldoxycarb in soil in the first year and in roots in the second year. Aldoxycarb and oxamyl reduced nematode populations to a similar degree.Key words: Aldicarb, aldoxycarb, oxamyl, Pratylenchus penetrans, Solanum tuberosum
OBSERVATION OF WINTER INJURY TO THE ROOTS OF APPLE TREES ASSOCIATED WITH SPRINKLER IRRIGATION PATTERN
Authors: QUAMME H. A. , BROWNLEE R.T.
Published: March 2010

After the winter of 1985–1986, winter injury to the roots of young apple trees was found to vary with position relative to irrigation sprinklers in several orchards growing at a site in the Okanagan Valley in British Columbia. Trees closest to sprinklers sustained significantly less injury than those more distant to the sprinkler. Water interception by the tree trunk and leaf canopy appeared to prevent uniform water distribution, especially in the vicinity of the crown. The explanation for the effect of water distribution on tree survival was not clearly determined but it did not appear to involve direct effects of a drought stress on tree hardiness because the previous season’s growth, which is considered indicative of drought stress, was not always related to injury. Increase in root injury with distance from sprinklers probably resulted in lower heat capacity of the soil and subsequent lower soil temperatures during the winter. Implications of these observations on irrigation practices to increase winter survival of fruit trees are discussed.Key words: Malus × domestica Borkh., winter survival, soil moisture, freezing stress
DROUGHT STRESS EFFECTS ON THE GRAIN YIELD AND PANICLE DEVELOPMENT OF SORGHUM
Authors: MANJARREZ-SANDOVAL PEDRO , GONZÁLEZ-HERNÁNDEZ VÍCTOR A. , MENDOZA-ONOFRE LEOPOLDO E. , ENGLEMAN E. M.
Published: March 2010

Many studies have reported responses to drought stress in sorghum (Sorghum bicolor (L.) Moench) but little is known about its effects on panicle development. To determine the stage of development most susceptible to water deficiency, in terms of grain yield components, eight plants of two sorghum lines were subjected to each of 10 single, successive drought stress treatments covering the entire life cycle. In each stress treatment, water was withheld until half of the plants remained wilted at sunrise. Effects on panicle development were also studied. Single sorghum plants were grown in pots containing a 3:1 soil (Typic Argiustoll)-sand mixture in a polyethylene greenhouse at Chapingo, Mexico. Drought stress during microsporogenesis destroyed the whole panicle. Prior to this stage, drought produced abortion of the panicle-branch primordia, and a reduction of 25–55% in the number of grains per mature panicle. Later drought stress periods did not reduce the number of grains per panicle, but reduced individual grain weight by as much as 50%. Consequently, the yield was reduced by drought stress periods at all stages of panicle development before physiological maturity. Furthermore, drought stress before anthesis slowed the subsequent developmental rate of the panicle; drought stress after anthesis accelerated it. The proportion of fertile pollen grains remained above 90% in all drought stress periods. It is concluded that microsporogenesis and the milk dough stage are the most sensitive stages of sorghum panicle development to water deficits.Key words: Sorghum bicolor (L.) Moench, grain sorghum, yield components, pollen sterility, sorghum cold-tolerance, microsporogenesis
COMPARISON OF MAIZE (Zea mays L.) GROWTH AND NITROGEN PARAMETERS UNDER HYDROPONIC AND FIELD CONDITIONS
Authors: WEILAND R. T. , McCLUNG A. M.
Published: March 2010

A comparison of biomass and nitrogen (N) parameters from 23 maize (Zea mays L.) inbreds was conducted between hydroponic culturing during two growth chamber studies and soil in the field for two harvests during 1984. The growth chamber studies and first field harvests were sampled at a similar growth stage (approximately nine-leaf); the second field harvest was at anthesis. Shoot dry matter accumulation was greater under hydroponic than under field conditions at a similar vegetative growth stage. Significant inbred differences for shoot biomass, reduced and total N contents and reduced and total N concentrations were determined for the growth chamber and both field harvests. Correlation coefficients were low and not significant (P < 0.05) between inbred parameters in the growth chamber and in the field. In summary, traits from hydroponic plants were not predictive of those from field plants. However, N parameters and biomass of inbreds harvested in the field at a mid-vegetative stage were predictive of inbred performance at anthesis.Key words: Zea mays L., maize, biomass, nitrogen, field, hydroponic
GENETIC IMPLICATIONS OF KERNEL HARDNESS VARIATION IN CANADA PRAIRIE SPRING WHEATS
Authors: LUKOW O. M. , McKENZIE R. I. H. , PAUW R. M. DE
Published: March 2010

The individual lines of three spring wheats were analyzed for kernel hardness by grinding time. Two of the wheats, HY320 and HY355, were composed exclusively of hard and soft lines; 38 and 74% hard lines, respectively. The third wheat, Oslo, consisted of a single hardness category and could be more accurately classified as a hard wheat. The grinding time responses of blends of HY320 and HY355 with known hard and soft wheats were predicted entirely from the proportion of hard and soft lines present in HY320 and HY355. There was no evidence of a major gene conferring medium kernel-hardness characteristics in spring wheat.Key words: Medium kernel-hardness, grinding time, wheat
PRECONDITIONING REDUCES THE SUSCEPTIBILITY TO DRYING INJURY IN CORN SEED
Authors: HERTER ULRICH , BURRIS JOSEPH S.
Published: March 2010

The characteristics of drying injury and drying tolerance of corn (Zea mays L.) seed were investigated on the inbred lines A632, B73, and Mo17. Initial drying at low temperature (preconditioning) to 30–39% seed moisture rendered high-moisture seed in most cases tolerant to subsequent drying at 50 °C. Drying at 20 or 35 °C resulted in more rapid and complete preconditioning of ear samples than storage at slow- or non-drying conditions. Drying of shelled samples at 35 °C did not accelerate the preconditioning effect compared with slower drying ear samples. Physiological factors other than moisture content are important criteria of high-temperature tolerance. These results offer an opportunity to more clearly define corn seed drying and begin to explain drying tolerance.
FORTUNE FIELD PEA
Authors: ALI-KHAN S. T. , NILSSON B. , JOHANSSON N. , BONIS P.
Published: March 2010

Fortune, a yellow-seeded cultivar of field pea (Pisum sativum L.) developed by Svalof AB, Sweden, was registered in Canada in 1987. Fortune is well adapted to the pea-growing areas of western Canada where it yields higher than the Century and Trapper cultivars.Key words: Pea (field, dry), cultivar description
THE SIGNIFICANCE OF FLORAL CHARACTERISTICS IN SEED PRODUCTION OF FOUR SUMMER RAPE CULTIVAR A-LINES WITH pol CYTOPLASM
Authors: McVETTY P. B. E. , PINNISCH R. , SCARTH R.
Published: March 2010

pol CMS A-line plants of three summer rape cultivars with altered floral morphology showed greater degrees of sideworking by leaf cutter bees than their respective B-line plants with normal floral morphology. However, A-line seed yields were equal to or greater than those of the B-lines.Key words: Flower morphology, rape pol CMS, A-line seed set
INFLUENCE DU CLIMAT SUR L’ACTIVITÉ NITRATE RÉDUCTASE AU COURS DU DÉVELOPPEMENT DE SIX VARIÉTÉS D’AVOINE
Authors: SAUVESTY A. , GENDRON G.
Published: March 2010

The influence of field climate on nitrate reductase activity (NR) and development was studied in six oat varieties. Of the monitored environmental factors, only temperature had a significant influence; a temperature increase accelerated plant development and increased NR. It was found that a measure of NR activity as early as the coleoptile stage of development indicated optimal environmental conditions for reduction of nitrate nitrogen in a given genotype.Key words: Nitrate reductase activity, development, climate, oat
GLUCOSINOLATE CONTENT OF MATURING PODS AND SEEDS OF HIGH AND LOW GLUCOSINOLATE SUMMER RAPE
Authors: MARCH G. DE , McGREGOR D. I. , SÉGUIN-SHWARTZ G.
Published: March 2010

3-Butenyl-, 4-pentenyl-, 2-hydroxy-3-butenyl- and 4-hydroxy-3-indolylmethylglucosinolate were found to be major glucosinolates in developing pod tissue and seed of both high and low glucosinolate lines of rapeseed. These glucosinolate profiles along with decreases in the glucosinolate content of pod tissue over a period of 18 d after pollination, and increases in the seed, were consistent with the pod tissue being a source of glucosinolate accumulating in the seed.Key words: Rapeseed, Brassica napus L., Cruciferae, glucosinolate, seed development
PYRAZOPHOS RESIDUES FROM TREATED GREENHOUSE AND GROWTH CHAMBER GROWN CHRYSANTHEMUMS
Authors: FRANK R. , BRAUN H. E. , STANEK J. , RITCEY G.
Published: March 2010

Potted and cut flower chrysanthemums (Chrysanthemum morifolium Ramat) were sprayed with 450 mg L−1 a.i. of pyrazophos grown under growth chamber and greenhouse conditions, respectively. A multiresidue method was tested for use on extraction and determination of pyrazophos on chrysanthemums and it was found to give 96% recoveries. Under growth chamber conditions pyrazophos disappeared from potted chrysanthemum plants with a half-life of between 19 and 25 d. On day 0, after allowing the spray to dry, 82% of the residue was removed by washing; at day 35, the amount removed was 43%. Removal by swabbing over the 35 d varied from 4.2% to 7.1%. In six commercial cut flower crops of greenhouse grown chrysanthemums, no evidence of pyrazophos breakdown was observed in plant tissues analyzed between the last spray date and sale of flowers 14 d later. During this period, swabs (wipings) dislodged between 2.7 and 4.6% of surface pyrazophos residue. These data strongly support a recommendation to wear gloves when handling both cut and potted chrysanthemums as workers can spend 30 and 60 h, respectively, handling the crop over each 13- to 15-wk production period.Key words: Pyrazophos, residues, chrysanthemums, greenhouse
ACTION DES FERTILISATIONS TARDIVES SUR LE GENÉVRIER (Juniperus chinensis ’Pfitzerana Aurea’) CULTIVÉ EN CONTENANTS
Authors: BIGRAS F. J. , RIOUX J. A. , THERRIEN H. P. , PAQUIN R.
Published: March 2010

Three-year-old plants of Juniperus chinensis ’Pfitzerana Aurea’ grown in containers were fertilized until August, September or October. Frost tolerance, water, mineral, total sugar, and starch content of shoots and roots were followed during the fall. Fall fertilization increased N and K content in the shoots and roots and accelerated shoot spring growth. Contents of P, Ca, Mg, Fe and Mn in the shoots and roots were not modified by the late fertilization regimes in the fall. Hardening of mature root and shoot was not affected by the prolongation of fertilization. Young roots did not harden. Water content of shoots decreased during hardening. The variability of root water content was too important to allow a detection of any reduction. At the end of fall, starch was almost completely hydrolyzed in shoots while it remained in appreciable quantity in roots. Total sugars increased more in shoots than in roots during the fall. The prolongation of fertilization had no influence on the total sugar or starch accumulation in shoots. Prolongation of the fertilization until October increased the starch and sugar content in roots.Key words: Juniperus chinensis ’Pfitzerana Aurea’, cold hardiness, growth, fertilization, water content, sugars, starch
EFFETS À LONG TERME DE L’ENRICHISSEMENT CARBONÉ ET D’UN APPOINT DE LUMIÈRE SUR LA PRODUCTIVITÉ DE LA ROSE CULTIVÉE EN SERRE
Authors: BALAZSOVITS J. , DANSEREAU B. , GAGNON S. , BEESON JR. R. C.
Published: March 2010

Roses (Rosa hybrida ’Royalty’) were grown at atmospheric CO2 concentrations of 330, 900 or 1500 ppm with or without supplemental lighting of 50 μmol m−2s−1 (PAR) provided by high pressure sodium lamps (HPS). Supplementary lighting and CO2 enrichment increased total yields of marketable flowers by 34 and 26%, respectively, compared with the control plants (natural lighting and CO2 concentration conditions). The combined effects of these treatments increased yield by 69% compared with the control. Improved flower quality and shortened production cycles were also observed. Flower stem length and diameter were not significantly affected by the treatments. The increased production levels obtained with CO2 enrichment and supplementary lighting were maintained throughout the treatment and post-treatment periods. These results indicate that rose plants respond positively to long-term CO2 enrichment and show beneficial residual effects to the treatments.Key words: Carbon dioxide, supplemental lighting, roses, growth, productivity
TOMATO YIELD AS RELATED TO DRIP LATERAL SPACING AND FERTILIZER APPLICATION ON TOTAL AND WETTED AREA BASIS
Authors: SINGH S. D. , SINGH Y. V. , BHANDARI R. C.
Published: March 2010

With drip irrigation systems, a part of the area is wetted at the soil surface. This raises the question of whether to program fertilizer rates on the total or wetted area of the plot. The objective of this investigation was to study the response of unstaked tomato plants (Lycopersicon lycopersicum L. Karst.) to drip application of fertilizers on the basis of total versus wetted surface area. Apart from the conventional broadcast and drip application of NPK fertilizers in liquid form, four other treatments were applied consisting of two rates of NPK, i.e., 224, 88 and 168 kg ha−1 on total plot area basis, and 56, 22 and 42 kg ha−1 on wetted surface area basis, factorially combined with 1.2- and-2.4-m lateral spacings, with N through drip, P and K banded. The study also included drip irrigation at 1.0 and 0.5 times the daily evapotranspiration (ET) rate factorially combined with drip application of NPK at 1.0, 0.75 and 0.5 times and broadcast application at 1.0 times the NPK rate. The NPK were, respectively, at 224, 88 and 168 kg ha−1. At the full grown stage, available water in the plant root zone was 60–100%. Root growth, soil temperature, and thermal conductivity were positively influenced by canopy cover and soil moisture regime. The development pattern indicated that 74% of the total root weight was confined to the top 15-cm soil layer. At the time of fruiting, the root weight declined in the soil layer with high water content. Drip irrigation equal to 0.5 ET required 25% less fertilizer than irrigation equal to ET, but irrigation at the latter rate and application of fertilizers to supply 224, 88 and 168 kg ha−1 of NPK, respectively, gave the highest yield of 90 t ha−1.Key words: Drip irrigation, root growth, spacing, multiple rows, fertilizer
INFLUENCE OF TRANSPLANTING DATE ON THE AGRONOMIC, CHEMICAL AND PHYSICAL CHARACTERISTICS OF FLUE-CURED TOBACCO
Authors: COURT WILLIAM A. , HENDEL JOHN G. , BINNS MICHAEL R.
Published: March 2010

A field experiment was conducted from 1983 to 1987 on a Fox loamy sand soil to study the effects of transplanting date on selected agronomic, physical, and chemical characteristics of flue-cured tobacco (Nicotiana tabacum L.) grown in Ontario. Tobacco plants (cv. Delgold) were transplanted at 3- to 5-d intervals commencing at approximately the middle of May and continuing for seven to nine planting dates into June. Delaying transplanting decreased yield, returns, total alkaloids, hexane extracts, lamina weight and percent lamina. Delaying transplanting also increased the chlorophyll content of the leaf but had no effect on reducing sugars, and only reduced grade index late in the planting season.Key words: Tobacco (flue-cured), transplanting date, yield, quality, tobacco chemistry
BROADENING THE GENETIC BASE OF CASSAVA, Manihot esculenta Crantz, BY INTERSPECIFIC HYBRIDIZATION
Authors: NASSAR NAGIB M. A.
Published: March 2010

Controlled crosses by vector insects resulted in the production of interspecific hybrids of cassava (Manihot esculenta Crantz) and Manihot species, while manual crosses failed. Marker genes for hairy stem, red disk, unribbed fruit, and foliaceous brackteoles proved efficient in recognizing interspecific hybridization between Manihot species and cassava.Key words: Wild cassava, Manihot neusana, Manihot anomala, interspecific hybridization, marker genes
THE GRL PASTE VISCOSITY INDICATOR FOR RAPID DETERMINATION OF α-AMYLASE IN CANADIAN RED SPRING WHEAT
Authors: KILBORN R. H. , KRUGER J. E. , TIPPLES K. H.
Published: March 2010

An instrument called the paste viscosity indicator (PVI) has been developed at the Grain Research laboratory (GRL) for measuring the paste viscosity of a heated ground grain-water slurry. Increased resistance offered to the stirring device upon heating a ground grain-water slurry is reflected in a voltage signal representing the current requirements of a small DC motor. Paste viscosity decreases with increasing α-amylase levels in the ground grain. The viscosity is measured by a digital panel meter which retains its reading after a testing period of 3 or 3.5 min. The machine is portable (8.8 kg) and does not require a running water source. Operation is in simple steps and sample containers are low cost and disposable. The method correlates well with Falling Number method over the range of 65 – 425 s for Canadian Western Red Spring wheat. As such, it may be well-suited for implementation into a carlot or cargo monitoring program for assessment of preharvest sprout-damage.Key words: Amylase, wheat, control, sprout-damage
NITROGEN, PHOSPHORUS AND MOISTURE EFFECTS ON ACCLIMATION OF WINTER PEAS
Authors: KEPHART KENNETH D. , MURRAY G. A.
Published: March 2010

Increased residual soil nitrogen and compaction-related waterlogging problems may relate to observed reductions in Austrian winter pea (Pisum sativum subsp. arvense (L.) Poir.) winter survival by influencing cold tolerance development. This study examines the influence of supplemental nitrogen and phosphorus on the cold tolerance of field acclimated Melrose Austrian winter peas. In 1981, on a poorly drained site, nitrogen rates of 34–101 kg N ha−1 increased LT50 to −6.9 from −7.4 °C for unfertilized peas through wk 7 of acclimation. Average winter pea LT50 after freezing at −4, −7 and −10 °C peaked at −7.7 °C at 7 wk of acclimation. LT50 was correlated (r = 0.85**) with declining epicotyl moisture (mg g−1). Survival declined from 51 to 8% between 7 and 9 wk of acclimation, corresponding to a threefold increase in average daily precipitation and waterlogged conditions. Tissue water levels (mg H2O epicotyl−1) between 7 and 9 wk of acclimation were correlated with LT50 (r = 0.64*). Winter peas cold tolerance peaked at −8.7 °C 9 wk after planting in 1982. High N rates reduced survival 16%, but did not influence LT50. Increased epicotyl N was correlated with survival (r = − 0.83**). Percent epicotyl moisture content correlated with LT50 (r = 0.70*) through 9 wk of acclimation. Phosphorus did not influence LT50 in either year.Key words: Pisum sativum subsp. arvense (L.) Poir., poor drainage, cold tolerance, plant water status, residual nutrient levels, pea (Austrian winter)
AN EVALUATION OF THE T-SUM METHOD FOR EFFICIENT TIMING OF SPRING NITROGEN APPLICATIONS ON FORAGE PRODUCTION IN SOUTH COASTAL BRITISH COLUMBIA
Authors: KOWALENKO C. G. , FREYMAN S. , BATES D. L. , HOLBEK N. E.
Published: March 2010

Seven field trials were conducted over 3 years (1984–1986) at two locations (Agassiz and Oyster River) in south coastal British Columbia to determine forage response to 100 kg N ha−1 applied at various time intervals in the spring according to the accumulation of average air temperatures above 0 °C from 1 Jan. (T-sum). A T-sum of 200 has been reported to be the optimum time for N application in western Europe and the United Kingdom. Both urea and ammonium nitrate were applied at the Oyster River location, while only ammonium nitrate was applied at Agassiz. First-cut forage dry matter production responded to the timing of N application in a variety of ways in the seven trials, with a decrease in growth as N was applied later in the season in most cases. In one trial, dry matter production was lowest at T-100 and T-150 compared to later times of application. Although there were variations among the trials, overall the highest yields occurred when N was applied at T-200 to T-300. Crop quality (%N or crude protein content), however, tended to increase as N was applied later in the season. Recovery of N in the plant and soil at harvest was relatively uniform for all times of N application and the distribution of extractable inorganic N in the soil profile suggested little N leaching. The dominant form of inorganic N found in the soil was ammonium. The cool soil temperatures and flush of plant and microbial activity probably contributed to the apparent lack of leaching and response of the grass to the N applied at various times early in the growing season. The timing of N application in the spring resulted in varying residual effects, whether N was applied or not after the first cut.Key words: N fertilization, yield, quality, timing, N recovery
THE ROOT SYSTEM OF CANADA THISTLE
Authors: NADEAU L. B. , BORN W. H. VANDEN
Published: March 2010

The severity of infestations of Canada thistle (Cirsium arvense (L.) Scop.) can be predicted by determining the potential of its root system to expand and produce new shoots. The root systems of young and old plants of Canada thistle were observed under field conditions found in Alberta. Eighteen-week-old plants grown in 1985 and 1986 had an average of 26 aboveground shoots, 154 underground shoots, and 111 m of roots with a diameter larger than 0.5 mm. The number of root buds and the regenerative capacity of the roots varied between years. Four times as many nonemerged root buds per meter of root were present on plants grown in 1986 compared to 1985, and 50% more shoots per meter were produced from 10-cm-long root fragments collected from 18-wk-old plants in 1986 than in 1985. On average, an 18-wk-old plant had the potential of producing 930 shoots if its root system was cut into 10-cm-long pieces. The depth reached by roots in a 10-yr-old stand was about 2 m, with the major part of the root system being below the top 20 cm of soil. There was no correlation between the number of root buds present at sampling time and the number of shoots produced from root fragments planted in pots in the greenhouse. An average of eight shoots per meter of root was produced, irrespective of sampling depth.Key words: Canada thistle, Cirsium arvense, root buds, root system, regenerative capacity
CONTROL OF QUACKGRASS IN FALLOW FROM SEVERAL GLYPHOSATE PLUS TILLAGE TREATMENTS AND ITS EFFECT ON THE SUBSEQUENT YIELD OF BARLEY
Authors: DARWENT A. L. , BAIG M. N. , GALLAGHER A. W. , LEFKOVITCH L. P.
Published: March 2010

The control of quackgrass (Agropyron repens (L.) Beauv.) using glyphosate applied with either a conventional sprayer or a rope wick applicator, each followed by several levels of tillage, was studied in 1983, 1984 and 1985. With the conventional sprayer, glyphosate was either applied alone or with ammonium sulfate (3.4 kg ha−1) and the surfactant, nonylphenoxy polyethoxy ethanol (0.5% vol/vol of spray volume). Applications made with the sprayer were more effective in reducing quackgrass culm density than those made with the rope wick applicator. The density of quackgrass culms declined as the number of tillage operations increased from one, performed at 115 or more days after herbicide application (DAT), to three performed at 5–8, 39–60 and 115 or more DAT. Doubling the rate of sprayer-applied glyphosate, from 0.8 to 1.7 kg acid equivalent ha−1, did not result in a reduction in the density of quackgrass culms. However, in 1 of the 2 years in which comparisons were made, both of these treatments reduced the density of quackgrass culms more than a similar application of glyphosate alone at 0.5 kg ha−1. The addition of ammonium sulfate and surfactant to glyphosate enhanced quackgrass control only at the 0.5 kg ha−1 rate and only in 1 of 2 yr at that rate. Glyphosate, applied at 0.5 kg ha−1 with the sprayer, and followed by three tillage operations consistently reduced the density of quackgrass culms by 95% or more. Both the herbicide and the tillage treatments resulted in increases in the yield of barley seeded the following year. In 2 of the 3 years, barley yields, averaged across tillage treatments, were greater in the plots where the sprayer had been used to apply the glyphosate treatments than in the plots where the rope wick applicator had been used. Barley yields decreased as the quackgrass culm density increased, although other factors seemed to have influenced the yields in one of the years.Key words: Glyphosate, tillage, barley, quackgrass, fallow
THE BIOLOGY OF CANADIAN WEEDS.: 92. Danthonia spicata (L.) BEAUV. IN ROEM. & SCHULT.
Authors: DARBYSHIRE S. J. , CAYOUETTE J.
Published: March 2010

Danthonia spicata, poverty-oat grass, is a native North American perennial grass of pioneer habitats. It invades agricultural lands in eastern Canada with dry soil and low fertility. Unpalatable to livestock, it is an increaser species in heavily grazed or nutrient depleted pasture. A polymorphic reproductive system incorporates chasmogamy, cleistogamy and heteromorphic diaspores (dispersal unit). Clavicipitaceous fungal parasites are often present and affect productivity, reproduction, competitive fitness and possibly predation of their hosts.Key words: Danthonia spicata, Poverty oat grass, weed biology
EFFECT OF PLANT DENSITY AND SEEDING DATE ON EARLY- AND LATE-MATURING SUNFLOWER HYBRIDS
Authors: GUBBELS G. H. , DEDIO W.
Published: March 2010

Field experiments were conducted in 1983, 1984 and 1986 to determine the response of Sun M 20 (early) and 894 (late) sunflower (Helianthus annuus L.) hybrids to three plant densities (30 000, 45 000 and 60 000 plants ha−1) at two seeding dates (18–24 May and 13–16 June). With increase in plant density, achene yields followed the same trends in each seeding date for both hybrids. Yields were similar at the 30 000 and 45 000 plant densities, but lower at the 60 000 density. Plant height and oil content of achenes increased while achene weight decreased with increase in plant density. Plant height was greater but achene weight, oil content and achene yield were lower in the late than the early seeding.Key words: Sunflower, Helianthus annuus L., plant density, seeding date
HAROSON SOYBEAN
Authors: BUZZELL R. I. , ANDERSON T. R. , HAMILL A. S. , WELACKY T. W.
Published: March 2010

Haroson is a backcross-derived soybean (Glycine max) cultivar which is similar to its recurrent parent, Hodgson, except for its resistance to Phytophthora megasperma f. sp. glycinea conferred by Rps1-c.Key words: Soybean cultivar, Haroson soybean
KG 100 SOYBEAN
Authors: BRADNER N. R. , SIMPSON R. D. , HADLOCK A. A.
Published: March 2010

KG 100 is a Maturity Group II soybean (Glycine max (L.) Merr.) cultivar which is 2 d later and higher yielding than the cultivar Jacques 103. Its main advantage is its yield performance and excellent phytophthora rot tolerance.Key words: Glycine max, KG 100 cultivar, soybean
COMPARISON OF THE EFFECT OF nap AND pol CYTOPLASMS ON THE PERFORMANCE OF INTERCULTIVAR SUMMER OILSEED RAPE HYBRIDS
Authors: McVETTY P. B. E. , EDIE S. A. , SCARTH R.
Published: March 2010

The objective of this study was to compare the performance of male fertility restored intercultivar F1 hybrids in the nap and pol cytoplasms to determine the relative effect on performance of these two male sterility inducing cytoplasms. F1 hybrids (all were 2n = 39 because a common 2n = 40 restorer line was used to produce the F1 hybrids) in both cytoplasms exhibited superior relative performance compared to the conventional cultivar Regent for seed yield, total dry matter and total protein yield. F1 hybrids in the pol cytoplasm performed significantly poorer than F1 hybrids in the nap cytoplasm for seed yield, total dry matter, harvest index, percent oil, total oil yield, and total protein yield. These results suggest a biological cost associated with the presence of the pol cytoplasm. The cost of the pol cytoplasm, relative to the nap cytoplasm, was affected by parental cultivar, but was consistent over a variety of environments.Key words: Cytoplasm cost, Brassica napus L., cytoplasmic male sterility, heterosis, hybrid
EFFECT OF ALTERING PLANT DENSITY ON GROWTH CHARACTERISTICS OF SUMMER RAPE
Authors: MORRISON M. J. , McVETTY P. B. E. , SCARTH R.
Published: March 2010

The effect of 15- and 30-cm row spacings and 1.5, 3.0, 6.0 and 12.0 kg ha−1 seeding rates on growth characteristics, as measured by growth analysis, of summer rape (Brassica napus L.) was studied under southern Manitoba growing conditions. Growing degree days (GDD) was used in the growth analysis formulae as a measurement of time. Over all seeding rates, summer rape grown in rows spaced 15 cm apart produced more dry weight (W), a greater leaf area index (LAI) and a greater leaf area duration (LAD) than when grown in rows spaced 30 cm apart. The 15-cm row spacing treatments had a higher crop growth rate (CGR) and a greater net assimilation rate (NAR) than the 30-cm row spacing treatments. Summer rape grown at seeding rates of 6.0 and 12.0 kg ha−1 had a greater W, LAI and LAD during vegetative development than summer rape grown at seeding rates of 1.5 and 3.0 kg ha−1. This was primarily due to increased plant density. After flowering there were no differences for W, LAI and LAD attributable to differences in seeding rates. Summer rape grown at seeding rates of 6.0 and 12.0 kg ha−1 had a lower CGR and NAR during flowering than that grown at 1.5 and 3.0 kg ha−1 seeding rates indicating that plants produced from lower seeding rates were more photosynthetically efficient than plants produced from higher seeding rates.Key words: Brassica napus, growth analysis, row spacing, seeding rates, rape (summer)
STUDIES OF RECOVERY FROM ARTIFICIALLY INDUCED LODGING IN SEVERAL SIX-ROW BARLEY CULTIVARS
Authors: BRIGGS K. G.
Published: March 2010

Artificial lodging treatments were applied to several six-row barley cultivars (Hordeum vulgare L.) in 1985 and 1986 in field plots at the University of Alberta Research Station, Edmonton, to determine the effects of lodging from the milk stage to maturity. For all cultivars the largest significant reduction in grain yield was obtained from lodging induced at the milk stage (average 21% yield reduction), with later lodging resulting in relatively less yield reduction (4% at preharvest). Significant effects of lodging treatments on thousand-kernel weight and hectoliter weight followed the same pattern. Incidence of disease (mainly scald) was significantly increased by the induction of lodging in one of the two years. Final lodging scores at maturity were significantly higher the later that lodging was induced, associated with generally reduced ability to recover from lodging. In 1 year of testing, the semidwarf cultivar Duke was found to be superior to the semidwarf cultivar Samson for lodging resistance, for ability to recover from lodging applied at all stages, for grain yield, thousand-kernel weight, and for disease resistance. In both years the cultivar Johnston had very poor lodging resistance and almost no ability to recover from lodging, whereas Leduc and Klondike were intermediate for these traits. A simple artificial lodging test is proposed for obtaining improved data on the lodging resistance and lodging recoverability of new cultivars.Key words: Lodging recovery, cultivar evaluation, disease level, grade reduction, growth stages, yield
RELATIONSHIPS BETWEEN SEEDLING TRAITS AND MATURE PLANT YIELD IN ALFALFA
Authors: SIMONS R. G.
Published: March 2010

To compare some seedling traits with the yield of alfalfa plants when grown as a crop stand, 1000 individually weighed seeds of Beaver alfalfa (Medicago sativa L.) were germinated in a growth chamber in a greenhouse mix containing soil. The dates of emergence and expansion of the first trifoliolate leaf, the weight of the first trifoliolate leaf, and the height, shoot number, leaf number and yield 10 wk after seeding were all correlated with each other. The seedlings were transplanted in late summer in to a 15 × 15-cm grid in the field, simulating a crop stand. Individual plant yields were determined in each of the two succeeding years. The number of shoots present at the first harvest was determined in the seedling year. There was no difference in the mean weight of seeds which emerged and those which did not. The mature plant traits were all strongly correlated with each other (P > 0.001). Although the seed weight and seedling traits had low correlations with mature plant traits (r < 0.25), the top 10% of seedlings on the basis of the date of first trifoliolate leaf expansion or seedling yield exceeded the population (averaged over the two years) by more than 31 and 41% respectively.Key words: Alfalfa, Medicago, seedling, selection, yield
NO-TILL PASTURE RENOVATION AFTER SWARD SUPPRESSION BY HERBICIDES
Authors: MALIK NAJIB , WADDINGTON JOHN
Published: March 2010

Four experiments were conducted to investigate methods for establishing legumes without cultivation in a pasture of low productivity because of nitrogen and phosphorus deficiencies on the Pathlow Community Pasture in northeastern Saskatchewan. Glyphosate applied at 2.2 kg ha−1 in strips 36 cm wide in early fall 1983 and 1984 was used as a standard vegetation control method. Other treatments were applied the same way. Alfalfa (Medicago media Pers. ’Beaver’) and cicer milkvetch (Astragalus cicer L. ’Oxley’) were seeded in the sprayed strips in late fall 1983 and spring 1985 using a triple-disk range drill. The degree of establishment was assessed initially by seedling counts and later by cover estimates each year until 1988. Legume establishment was best in strips where the vegetation was killed. The addition of 5% wt/vol ammonium sulphate to glyphosate did not improve establishment of the legumes significantly. Fluazifop-butyl, quizalofop-ethyl, and haloxyfop-methyl had little effect on the resident vegetation and legume establishment was poor. Sethoxydim tested at 0.8 kg ha−1 appeared to provide less suppression of vegetation than was achieved with glyphosate at 1.1 kg ha−1 but legume establishment was similar. There was no benefit to drilling phosphorus at rates up to 60 kg ha−1 with the seed.Key words: Pasture, renovation, no-tillage seeding, alfalfa, cicer milkvetch, sward suppression
SEED POD DEHISCENCE IN BIRDSFOOT TREFOIL, Lotus conimbricensis, AND THEIR INTERSPECIFIC SOMATIC HYBRID
Authors: YANG J. B. , SOMERS D. A. , WRIGHT R. L. , McGRAW R. L.
Published: March 2010

Application of gibberellic acid to the floral stigma of a sterile somatic hybrid between birdsfoot trefoil (Lotus corniculatus L.) and L. conimbricensis Wild. induced development of seedless pods. Pods formed from gibberellic acid-treated flowers of birdsfoot trefoil, somatic hybrid, and L. conimbricensis exhibited 93%, 3%, and no dehiscence, respectively, after incubation at 15.5% relative humidity for 72 h. Indehiscence of the somatic hybrid was associated with reduced lignification of the seed pod mesocarp compared with birdsfoot trefoil as determined by phloroglucinol-HCL staining. Indehiscence was apparently transferred from L. conimbricensis, which also exhibited a low level of mesocarp lignification.Key words: Lotus corniculatus L., protoplast fusion, pod dehiscence
AGRONOMIC PERFORMANCE OF SEMI-DWARF AND NORMAL HEIGHT SPRING WHEATS SEEDED AT DIFFERENT DATES
Authors: BAKER R. J.
Published: March 2010

Emergence, maturity, and yield of four semi-dwarf and five normal height spring wheat (Triticum aestivum L.) genotypes were evaluated in 10 replicated field experiments at Saskatoon in 1985–1987. Although significant crossover interactions were observed, semi-dwarf and normal height genotypes responded similarly to date of seeding.Key words: Triticum aestivum, seeding date, crossover interaction, wheat (spring)
NURSERY PERFORMANCE OF SELECTED SHADE-TREE SPECIES GROWN IN "FIELD-GROW" FABRIC CONTAINERS
Authors: REMPHREY W. R. , RIMMER S. R. , BLOUW M. J.
Published: March 2010

Performance of bare-root stock of Patmore green ash (Fraxinus pennsylvanica Marsh.), Dropmore basswood (Tilia × flavescens A. Br.) and silver maple (Acer saccharinum L.) growing in two sizes of "Field-grow" in-the-ground fabric containers (46-cm and 56-cm diameter) was compared with uncontainerized controls over a 4-yr period. Root systems of Field-grow plants examined were more fibrous; feeder roots penetrating the container wall were swollen adjacent to it. Large roots, especially of silver maple, also penetrated the seam between the side walls and plastic bottom. Field-grow silver maple and ash grew progressively less than control plants on or after the first growing season, indicating diminutive effect of the containers. Basswood, which was slower to establish, showed no such response until the fourth growing season.Key words: Fraxinus pennsylvanica ’Patmore’, Tilia flavescens ’Dropmore’, Acer saccharinum, nursery production, "Field-grow" containers
RADIATION HORMESIS OF FIELD-SEEDED BROCCOLI, PARSNIP AND CAULIFLOWER
Authors: SHEPPARD S. C. , CHUBEY B. B.
Published: March 2010

Very low doses of irradiation have been reported to cause stimulatory or hormesis effects on plants. Irradiating the seed has been reported to improve emergence, and this would be a benefit for valuable, field-seeded crops. Over 3 yr, irradiation significantly increased the first emergence counts of broccoli, by about twofold, and the time to 50% of final emergence was advanced by about 1 d. In 1 yr trials, 50% of final emergence was advanced by 3 d for parsnip, but there was no effect for cauliflower. After emergence was complete, all plots were thinned and there were seldom any significant hormesis effects on yield parameters.Key words: X-ray, emergence, vigor, ionizing radiation, cole crop
EFFECTS OF NITROGEN, INOCULATION AND GRAFTING ON EXPRESSION OF SUPERNODULATION IN A MUTANT OF Phaseolus vulgaris L.
Authors: BUTTERY B. R. , PARK S. J.
Published: March 2010

A supernodulating mutant of Phaseolus vulgaris L. grew much like its parent line OAC Rico, but plant weights were significantly lower at 26 and 39 d after seeding. Between these sampling dates relative growth rate was greater in the supernodulator than in OAC Rico. Both parent and mutant responded to combined nitrogen by increases in plant weight. Continuous treatment with 14 mM combined N severely reduced nodulation of the mutant as well as OAC Rico whereas 2.1 mM and 14 mM discontinued after 10 d stimulated nodule mass in the mutant. Specific nodule activity (acetylene reduction) was lower in the mutant than OAC Rico. Leaf nitrate reductase activity was similar in both. In the absence of Rhizobium, but with 2.1 and 14 mM combined N, the mutant and OAC Rico grew similarly. Reciprocal grafting of shoot and root between the mutant and OAC Rico established that the supernodulating characteristic was controlled by the shoot.Key words: Acetylene reduction, grafting, nitrate reductase, Rhizobium, supernodulation, bean (common; field)
EFFECTS OF CROP ROTATIONS AND FERTILIZATION ON YIELDS AND QUALITY OF SPRING WHEAT GROWN ON A BLACK CHERNOZEM IN NORTH-CENTRAL SASKATCHEWAN
Authors: ZENTNER R. P. , CAMPBELL C. A. , BOWREN K. E. , EDWARDS W.
Published: March 2010

Effects of rotation length, crop sequence, and fertilization on yields and quality of spring wheat (Triticum aestivum L.) were examined for eight crop rotations over a 27-yr period (1960-1986) on an Orthic Black Chernozem at Melfort, Saskatchewan. The silty clay loam soil had an initial organic N content of about 0.55% (0-to 15-cm depth). During 1960-1971, fertilized plots received N and P based on general recommendations for the region; thereafter, fertilizer was applied based on soil tests. Yields of wheat grown on fertilized fallow were similar for fallow-wheat, fallow-wheat-wheat (F-W-W), and a 6-yr fallow-wheat-legume hay rotation (avg. 2519 kg ha−1 in 1960-1971 and 3036 kg ha−1 in the wetter 1972-1986 period). In contrast, yields of wheat grown on fertilized stubble in a F-W-W rotation (avg. 2113 kg ha−1 in 1960-1971 and 2775 kg ha−1 in 1972-1986) averaged 34% higher than yields of continuous monoculture wheat due to fewer observed weed and disease problems. Fertilized stubble wheat yields in F-W-W averaged 88% of comparable fallow wheat yields, while continuous wheat averaged only 66%. Fertilizer increased fallow wheat yields by 14-18%. Stubble wheat yields were increased 11–16% for 3-yr rotations and 26% for continuous wheat during 1960-1971 when relatively low rates of N fertilizer were applied, and 22–31% and 49% for these same rotations, respectively, during 1972-1986 when moisture was more favorable and soil test criteria were used. Inclusion of grass-legume hay or legume green manure crops in the rotations provided no yield benefit for subsequent wheat crops in this fertile soil. The yields of wheat from fertilized rotations increased significantly with years of study reflecting the higher fertilizer rates used in later years and use of improved production technologies. Wheat yields of unfertilized treatments generally increased or showed no trend with time, thus providing no evidence of declining soil fertility. Crude protein concentration and total N yield of the grain were significantly increased by fertilization and inclusion of a grass-legume hay crop in the rotation. Total grain P yield of wheat was also influenced by fertilizer and by rotation, while volume weight of grain was unaffected by treatment.Key words: N and P fertilizer; grass-legume hay; legume green manure; crop sequence; protein
DEVELOPMENT OF LOW GLUCOSINOLATE MUSTARD
Authors: LOVE H. K. , RAKOW G. , RANEY J. P. , DOWNEY R. K.
Published: March 2010

The objective of this study was to develop low glucosinolate mustard (Brassica juncea Coss.). This was accomplished through an interspecific cross between an Indian type 3-butenyl glucosinolate containing B. juncea selection and a "Bronowski-gene(s)" containing low glucosinolate B. campestris L. followed by backcrossing to the B. juncea parent. Seed of BC1F2 plants, and selected plants of BC1F3 and BC1F4 generations were analyzed for glucosinolate content by gas chromatography. Total aliphatic glucosinolate contents of individual BC1F2 plants ranged from 57 to 204 μmol g−1 meal. A single BC1F3 plant grown from the BC1F2 plant with the lowest glucosinolate content, identified as 1058, was found to contain less than 1 μmol g−1 meal of total aliphatic glucosinolates. The glucosinolate content in individual plants of the BC1F4 generation of plant 1058 ranged from 0.8 to 2.9 μmol g−1 meal. Field grown progeny of 1058 at three locations in 1987 and at one location in 1988 in Saskatchewan contained less than 10 μmol g−1 meal of total aliphatic glucosinolates. Therefore, the low glucosinolate characteristic of selection 1058 can be considered genetically stable. Progeny of plant 1058 had plant morphology and seed coat reticulation of B. juncea, but poor fertility (< 5 seeds per pod). The development of this low glucosinolate plant is an achievement that should allow the breeding of canola quality oilseed B. juncea mustard.Key words: Mustard, glucosinolate, Brassica juncea, interspecific cross