bluuebunny/crossref_metadata_2025 huggingface dataset:
AN ASSESSMENT OF LONG-TERM EFFECTS FROM SPRING AND SUMMER APPLICATIONS OF AMMONIUM NITRATE ON ORCHARDGRASS
Authors: KUNELIUS H. T. , MacLEOD J. A. , McRAE K. B.
Published: March 2010

Orchardgrass (Dactylis glomerata L.) was grown for 5 yr on a fine sandy loam fertilized with ammonium nitrate at 40–120 kg N∙ha−1 applied in either spring or summer or in combination. Stands were cut two or three times during each growing season. Single N applications in spring increased annual yield by about 11% over equivalent summer applications. For split applications no significant difference in annual yield was found regardless of whether the greater fraction was applied in spring or summer. A second order polynomial was found to explain almost all of the variation in the response curve over time for dry matter yield. Application of 120–165 kg N∙ha−1 were required to maintain a uniform yearly production. There was variation in the mean seasonal N concentration over years but with few clear trends. The N concentrations in cuts 1 and 2 were principally determined by the rate of N applied in the spring and summer but there was a carryover effect from the first to the second cut for the highest rate of applied N in the 4th and 5th years.Key words: Dactylis glomerata L., herbage production, tissue N concentration
POLISH RAPESEED AS A COMPANION CROP FOR ESTABLISHING FORAGES IN NORTHEASTERN SASKATCHEWAN
Authors: WADDINGTON J. , BITTMAN S.
Published: March 2010

Forages were seeded with and without a Polish rapeseed (Brassica campestris L.) companion crop at two dates in each of 3 yr. In each test, forage seedlings grew much better where seeded alone; growth under the companion crop varied from poor to fairly good, depending on the year and the forage species. Russian wild ryegrass (Elymus junceus Fisch.) established poorly under rapeseed. Bromegrass (Bromus inermis Leyss.) establishment was satisfactory in all tests, although production in the year following was usually much less than where it was seeded alone. Alfalfa (Medicago sativa L.) and sainfoin (Onobrychis viciaefolia Scop.) establishment was poor to fair under rapeseed. A mid-May seeding date with the companion crop resulted in better forage growth by fall than a later seeding date. A feature of all tests was the severe infestation of volunteer rapeseed the year following seeding in all forages except bromegrass. Because of growth suppression during the establishment year, and difficulties with volunteer rapeseed in legumes in the year following establishment, it is suggested that Polish rapeseed is not a good companion crop when establishing legumes and Russian wild ryegrass.Key words: Bromegrass, alfalfa, Russian wild ryegrass, sainfoin, rapeseed, companion crops, forage establishment
STUDIES WITH SAND CULTURE FOR BENTGRASS GREENS
Authors: NELSON S. H. , SCHROEDER W. R.
Published: March 2010

The growth and development of Penncross bentgrass was studied for 3 yr on eight sand blends consisting of variable particle size. All were perched over a layer of coarse aggregate (6–12 mm). Germination and establishment rate were slower with those blends where particles smaller than 0.5 mm had been removed. Spring recovery rate after the first winter was also slower in the blends with the smaller particles removed, but this was not apparent after the second winter. The hydraulic conductivity varied greatly in the sand blends without turf, but there were no significant differences between treatments when turf was present in the 2nd and 3rd years. Total root growth or the amount of roots recovered from the peat-moss-amended top 7.5 cm of the 30-cm profile did not differ significantly among treatments in the final 2 yr although compaction reduced the amount of root present. In the lower, unamended portion of the profile there was a trend toward a greater amount of root growth for 2 yr when the finer particles were removed, but there was no significant difference in the 3rd year. The study demonstrated the ameliorating effect of developing turf on hydraulic conductivity in these vastly different sand blends and suggests that sands, even though not in the recommended range of particle size, can still offer relief to the compaction, drainage, and root growth problems encountered in the culture of bentgrass greens.Key words: Agrostis palustris, perched water table, germination rate, hydraulic conductivity, root growth, compaction
A COMPARATIVE ANALYSIS OF LEAF CHLOROPHYLL FLUORESCENCE, HILL REACTION ACTIVITY AND 14C-ATRAZINE TRACER STUDIES TO EXPLAIN DIFFERENTIAL ATRAZINE SUSCEPTIBILITY IN WILD TURNIP RAPE (Brassica campestris) BIOTYPES
Authors: ALI A. , MACHADO V. SOUZA
Published: March 2010

Leaf chlorophyll fluorescence in susceptible B. campestris L. plants was greatly enhanced and the Hill reaction activity of isolated chloroplasts was inhibited by 10−4 M atrazine. The herbicide did not produce similar responses in resistant plants. 14C-atrazine was used to determine if, in addition, there were differences in uptake, translocation, and metabolism of the herbicide by the susceptible and resistant biotypes. The 14C-atrazine in nutrient solution was readily taken up by the roots of both biotypes and was rapidly translocated to the shoot. The 14C-atrazine was quickly metabolized and after a 24-h period 56 and 63% of the extractable radioactivity in susceptible and resistant plants, respectively, was present as metabolites, the major one being 2-hydroxyatrazine. Following a foliar application, less than 1% of the applied radioactivity moved into other parts of the plant. These results clearly show that triazine resistance in wild turnip rape is based in the chloroplast and that uptake, translocation, and metabolism of the herbicide play no decisive role in selectivity between the susceptible and resistant biotypes.Key words: Atrazine selectivity, Brassica campestris, chlorophyll fluorescence, Hill reaction, atrazine metabolism.
SUPPLEMENTARY LIGHTING FOR RESEARCH GREENHOUSES
Authors: CLARK E. ANN , DEVINE M. D.
Published: March 2010

The growth and development of six plant species were measured under a standardized photosynthetic photon flux density (PPFD) supplied by fluorescent, metal halide, or high-pressure sodium lamps. Overall, plant growth and seed yield were in the order of high-pressure sodium > metal halide > fluorescent. Although the units tested were unable to supply a uniform, high flux density, acceptable plant growth was achieved under the compromise arrangements used.Key words: Fluorescent, metal halide, high pressure sodium, supplementary lighting
EFFECT OF HARVEST TIME AND DRYING METHOD ON QUALITY AND GRADE OF SPRING TRITICALE
Authors: CLARKE JOHN M.
Published: March 2010

Two spring triticale (X-Triticosecale Wittmack) cultivars, Carman and Welsh, and one advanced-generation breeding line were grown under field conditions for 3 yr to study the effects of harvest time and drying method on quality and grade. Plots were harvested at six to seven intervals when kernel water concentration was in the 1000 to 100 g water per kilogram kernel dry weight range. Grain was dried in the field in simulated windrows or artificially dried in a forced-air oven at 40–45 °C. Test weight, 1000-kernel weight, falling number, germination, and commercial grade were determined. Test weight increased with decreasing kernel water concentration at harvest, particularly in the artificially dried treatment. Test weight was greater in the windrowed than in the artificially dried treatment, especially for harvests made at high water concentrations. Harvest at high kernel water concentrations tended to reduce 1000-kernel weight, more so in the windrowed than in the artificially dried treatment. Although falling numbers were influenced by harvest time and drying method, there were no clear trends. Germination was reduced in material cut at a kernel water concentration above 680 g∙kg−1 in 1 of 2 years. Grades were reduced by artificial drying of grain, particularly when harvested at high kernel water concentrations. Grades were unaffected by windrowing at kernel water concentrations of up to 1000 g∙kg−1.Key words: X-Triticosecale Wittmack, test weight, falling number, germination, windrow
ALFALFA (Medicago sativa L. and M. falcata L.) CULTIVAR × ROW SPACING INTERACTION ON YIELD AT A SEMIARID ENVIRONMENT IN SOUTHWESTERN SASKATCHEWAN
Authors: IRVINE R. B. , JEFFERSON P. G.
Published: March 2010

Ten alfalfa (Medicago sativa L. and M. falcata L.) cultivars were grown in 30- and 90-cm row spacings on a dryland site at Swift Current, Saskatchewan. From 1979 to 1981 there was a significant cultivar × spacing interaction on yield at every harvest except the second cutting in 1981. The M. falcata cultivars, Anik and Sc MF 3713, were better able to exploit the lower plant density at the 90-cm spacing than M. sativa cultivars, Thor and Banner. Yields of Anik and Sc Mf 3713 increased with 90-cm compared to 30-cm spacing, while Thor and Banner decreased. The creeping rooted cultivars Rambler and Rangelander did not differ from Anik or Sc Mf 3713 in yield response to increased row spacing. This suggests that the observed cultivar × spacing interaction was due to morphological and/or physiological traits associated with the M. falcata cultivars, other than the creeping rooted habit.Key words: Creeping rooted, drought tolerance, WUE
CONTROL OF BROADLEAVED WEEDS IN CREEPING RED FESCUE GROWN FOR SEED
Authors: DARWENT A. L. , SMITH J. H.
Published: March 2010

Field studies were conducted from 1977 to 1981 on the control of dandelions (Taraxacum officinale L.) and other broadleaved weeds in creeping red fescue (Festuca rubra var. geniuna L.). Creeping red fescue was established either alone or with a companion crop of barley (Hordeum vulgare L.) or rapeseed (Brassica campestris L.). The barley was harvested in early August for fodder or in early September for grain. Several herbicide treatments were applied to each crop situation. Bromoxynil plus MCPA applied at 0.28 + 0.28 kg a.i./ha when the creeping red fescue was in the three-leaf stage (and 1–2 mo old) controlled 75% or more of the annual weeds during the year of seeding. This herbicide combination also provided substantial control of dandelions and other weeds during the year following seeding. A second herbicide treatment of dicamba plus 2,4-D at 0.28 + 0.56 kg a.i./ha in May of the year following seeding provided an improvement in the control of dandelions and other weeds over the single application of bromoxynil plus MCPA in some but not all seedings. The use of rapeseed as a companion crop without any herbicide treatments did not provide consistent weed control. Seed yields during the second production year were increased by 25% or more from the use of herbicide treatments when creeping red fescue was seeded alone or with barley harvested for fodder. First production year seed yields were not increased by any of the herbicide treatments. Similarily, first and second production year seed yields were not increased by any of the herbicide treatments when creeping red fescue was seeded with barley harvested for grain. Harvesting barley as fodder rather than grain produced marginally higher first production year creeping red fescue seed yields but had no effect on second production year seed yields.Key words: Creeping red fescue, dandelion, companion crop, 2,4-D plus dicamba, MCPA plus bromoxynil
TOLERANCE OF GLENLEA AND NEEPAWA WHEAT TO CLOPYRALID
Authors: O’SULLIVAN P. A. , KOSSATZ V. C.
Published: March 2010

Glenlea wheat was tolerant to field applications of clopyralid at 0.1–0.9 kg/ha at the three- and six-leaf stages and boot stage. Neepawa yield was reduced with 0.9 kg/ha at the three- and six-leaf stages and with 0.6 kg/ha at the boot stage.Key words: Wheat, tolerance, clopyralid
EFFECTS OF LIQUID HOG MANURE APPLICATION RATES ON SILAGE CORN YIELD AND NUTRIENT UPTAKE
Authors: ANTOUN H. , VISSER S. A. , CESCAS M. P. , JOYAL P.
Published: March 2010

The objective of this work was to determine the response of corn to liquid hog manure surface applied at rates of 28, 56 and 112 tonnes/ha. In greenhouse trials, yield of corn grown for 4 wk on St. Jude loamy sand was not affected by manure application. On Kamouraska silty clay, only manure applied at a rate of 112 tonnes/ha increased corn yield, as compared to the non-treated control. Corn response on Janvier sandy clay loam improved with increasing rate of manure application up to 56 tonnes/ha. Application of 112 tonnes/ha (325 kg N/ha) manure increased N content of corn and had a significant residual effect as noted by the high yield obtained at the second harvest. In a 2-yr field experiment on Kamouraska soil, corn yield was significantly higher at 112 tonnes/ha (avg 432 kg N/ha) than chemical fertilizer application at 150 kg N/ha, and manure-treated soil contained more P, Ca and Mg after the first year. Nutrient uptake by corn increased with amount of manure applied. However, corn whole plant composition was not affected by rate of manure application. N recovery was higher from manure at 28 or 56 tonnes/ha than from a chemical fertilizer (150 kg N/ha, 65.5 kg P/ha and 125 kg K/ha). At the rates applied, the liquid hog manure did not result in reduced corn yield.Key words: Corn yield, hog manure, nutrient uptake, silage corn
NITROGEN NUTRITION AND N-ASSIMILATION IN MAIZE SEEDLINGS
Authors: HANDA SANGITA , HUBER D. M. , WARREN H. L. , TSAI C. Y.
Published: March 2010

The effect of ammonia on plant growth is influenced by the stage of growth and concentration of N. This study evaluates the activity of enzymes involved in NH4+ assimilation and the relationship of these enzymes to maize seedling development. Various concentrations of NH4Cl applied at 3, 8, 13, 18 and 23 days after germination were evaluated. Activities of glutamate synthase and glutamine synthetase were not altered when NH4+ was applied to 3-day-old seedlings; however, there was increased enzymatic activity whe N was applied to 18- or 23-day-old seedlings. Glutamate dehydrogenase appears to be an important enzyme for the assimilation of NH4+ by roots of maize seedlings. The growth rate of seedlings receiving NH4+ varied at different stages of development. Prolonged N stress (longer than 18 days) reduced the rates of subsequent dry matter accumulation, indicating that an adequate availability of N throughout early growth is critical for maximum nutrient efficiency and optimum plant development. Greatest growth was observed with a combination of both NO3− and NH4+ sources of N.Key words: Corn, nitrogen nutrition, enzymes (N assimilating), seedling development
EVALUATION OF ALFALFA CULTIVARS FOR REACTION TO CROWN AND ROOT ROT
Authors: MICHAUD R. , RICHARD C.
Published: March 2010

Fourteen alfalfa cultivars were grown for 2 yr at three locations and evaluated for forage dry matter yield and crown and root rot. Significant differences were found among cultivars for dry matter yield. All cultivars were affected by crown and root rot, most cultivars showing between 20 and 30% of infected tissues. Differences were observed among as well as within the cultivars for disease severity. The frequency of disease-free plants was less than 1.3% of the plants evaluated. Correlation between root rot index and forage yield was −0.87 [Formula: see text] when data were pooled over years and locations.Key words: Lucerne, root rot, cultivar, yield
SAND ROOTZONES FOR KENTUCKY BLUEGRASS
Authors: NELSON S. H. , McCLENNAN G. L.
Published: March 2010

The growth and development of Kentucky bluegrass was studied for 3 yr on eight sand blends consisting of variable particle sizes. All were perched over a coarse layer (6–12 mm diam). No differences in germination, establishment, or color over the 3 yr were observed. Without turf the hydraulic conductivity varied greatly in the sand blends. The high conductivity levels were greatly reduced with the developing turf. There was greater downward water movement in those plots with most of the finer particles removed and this greater percolation continued throughout the experiment as the turf developed. In the compacted plots, however, significant differences in percolation rates had disappeared by the third year. When most of the finer particles had been removed, there was a trend toward less total root production with a redistribution of roots to the middle portions of the profiles. This trend was more evident on the compacted plots. The study demonstrated that developing turf has an ameliorating effect on hydraulic conductivity on these vastly different sand blends and suggests that sands, even though not in the recommended range of particle size, can still offer relief to the compaction, drainage, and root growth problems encountered in Kentucky bluegrass playing fields.Key words: Poa pratensis, perched water table, hydraulic conductivity, root growth, compaction
CONTROL OF Teucrium canadense L. var. Canadense WITH HERBICIDES
Authors: SWANTON C. J.
Published: March 2010

Teucrium canadense L. var. canadense, commonly known as germander, was identified as a major weed problem of corn and soybeans growing in lowland areas in southwestern Ontario. Field experiments with postemergence herbicides showed that growth of shoots from established plants and regrowth of new sprouts from rhizomes was effectively controlled by applications of glyphosate at 1.12, 1.68 and 2.24 kg/ha when applied in August and September. Postemergence applications of 2,4-D + dicamba + mecoprop applied at 0.68 + 0.25 + 0.19 and 1.36 + 0.51 + 0.37 kg/ha or dicamba at 0.56 and 1.0 kg/ha applied at the sprout to prebloom stage of growth resulted in 75–88% control of shoot growth and 3–16% control of regrowth. Linuron, bentazon and amitrole gave 57–77% control of shoot growth. Control with herbicides was depended upon proper herbicide selection, rate of active ingredient used and growth stage of the weed at time of herbicide application.Key words: Teucrium canadense L. var. canadense, herbicides, control
RESPONSES OF WHITE BEAN TO AMMONIUM OR NITRATE NUTRITION AT THREE TEMPERATURES
Authors: MacLEOD K. C. , ORMROD D. P.
Published: March 2010

The response of white beans (Phaseolus vulgaris L. ’Seafarer’) growing in quartz sand to ammonium (NH4+) or nitrate (NO3−) N source was investigated in controlled environments at 27°/11°, 19°/11° and 19°/7 °C day/night temperatures. Ammonium-treated plants developed leaf chlorosis and necrosis. The pH of leachate from the rooting medium dropped from an initial level of 6.0 to values of 3.5–3.9 for NH4+-treated plants, while the pH increased to about 6.5 for NO3−-treated plants. The NO3−-treated plants had much greater growth overall than NH4+-treated plants. Temperature had little or no effect on plant responses to N source. The NO3−-treated plants contained higher NO3− and Ca but lower total N, NH4+ and P than NH4+-treated plants.Key words: Temperature, ammonium, nitrate, white bean, navy bean, phytotoxicity
VISUAL INDICATORS FOR DETERMINING THE OPTIMUM WINDROWING TIME FOR BUCKWHEAT
Authors: GUBBELS G. H. , CAMPBELL C. G.
Published: March 2010

Two buckwheat (Fagopyrum esculentum Moench.) cultivars, Mancan and CM 169, were grown in the field for 3 yr. Various plant characteristics were recorded to establish visual indicators of optimum windrowing date. Optimum yield was obtained by windrowing when flowering was almost finished and 75% of the seeds had turned brown.Key words: Buckwheat, maturity, windrowing time
EFFECTIVE XYLEM RADIUS OF THE SUBCROWN INTERNODE OF BARLEY (Hordeum vulgare L.)
Authors: IRVINE R. B. , THERRIEN M. C.
Published: March 2010

Factors influencing the effective xylem radiums (EXR) of the subcrown internode of barley were investigated. The size of the barley seed did not affect internode length but large seed produced larger EXR. Deep planting increased the length of the subcrown internode and decreased EXR. The cultivar Abee had the longest internode and the smallest EXR. The best predictor of EXR appears to be the size of the largest xylem vessel.Key words: Hordeum vulgare, barley, xylem radius, crown depth
RESIDUES OF ETHYLENEBISDITHIOCARBAMATES (EBDC) AND DINOCAP IN GREENHOUSE CUCUMBER FRUITS
Authors: RIPLEY BRIAN D. , FRANK RICHARD , JARVIS WILLIAM R. , FISHER J. CLEMENT
Published: March 2010

By the third day following the application of the last of three sprays of the fungicides dinocap and mancozeb to greenhouse cucumber fruits, residues, on a whole-fruit basis, did not exceed the levels permitted in Canada of 0.1 μg/g and 7 μg/g, respectively. The permitted level of zineb equivalent EBDC was never exceeded following the application of a dinocap-mancozeb commercial fungicide formulation. The results support an Ontario recommendation for a 3-day waiting period between fungicide application and harvest in the case of EBDC, and argue for a reduction in the 30-day period for dinocap.Key words: Residue, dissipation, mancozeb, dinocap, cucumber, greenhouse
CO2 EXCHANGE RATES AND STOMATAL DIFFUSIVE RESISTANCE IN SOYBEAN EXPOSED TO O3 AND SO2
Authors: CHEVONE B. I. , YANG Y. S.
Published: March 2010

Soybean (Glycine max (L.) Merr. ’Essex’) plants, 21–24 days old, were exposed to 400 μg/m3 (0.20 μL/L) ozone (O3) and 1865 μg/m3 (0.70 μL/L) sulfur dioxide (SO2) in various combinations. Fumigation was administered for 2 h either as single pollutants (O3 and SO2), simultaneously (O3 + SO2), or in overlapping pollutant combinations (O3 for 1 h followed by O3 + SO2 or SO2 for 1 h followed by SO2 + O3). Carbon dioxide exchange rates (CER) of trifoliolate leaves were measured during the fumigations, and stomatal resistance to H2O was determined immediately before and after pollutant exposure. At the end of a 2-h exposure, O3 and SO2, administered separately, did not significantly affect CER. Exposure to O3 followed by O3 + SO2, SO2 followed by SO2 + O3, and continuous O3 + SO2 significantly reduced CER to 62, 41 and 33% of preexposure rates, respectively. Stomatal resistance was not significantly altered by pollutant fumigation except in the simultaneous application of O3 + SO2 where an 11% decrease occurred. Reductions in CER in response to fumigation were not attributed to changes in stomatal resistance, but appeared to result from changes in mesophyll resistance. A proposed mechanism for pollutant-induced reduction in CER is discussed.Key words: Air pollution, net photosynthesis, pollutant mixtures
EFFECTS OF IRRIGATION AND FERTILIZER N ON N2(C2H2) FIXATION AND YIELD OF WHITE BEAN AND SOYBEAN
Authors: SMITH D. L. , HUME D. J.
Published: March 2010

White bean (Phaseolus vulgaris L.) generally fixes less atmospheric nitrogen (N2) than does soybean (Glycine max [L.] Merrill). Experiments were conducted to assess the sensitivity of both species to irrigation and fertilizer N. Trials were conducted near Elora, Ontario in 1981 to 1983 and at Cambridge, Ontario in 1983. Treatments included applying 1 cm/day of irrigation water, 200 kg N/ha added throughout the season (400 kg N/ha at Elora in 1983), 1 cm/day of irrigation water plus N, and a control with no added fertilizer or water. Irrigation increased N2(C2H2) fixation in white bean by four to 150 times and in soybean by two to four times. Nodule mass and nodule size also were generally increased more in white bean than in soybean. Specific nodule activity (SNA) was increased similarly in both species. Fertilizer N decreased N2(C2H2) fixation consistently, and also lowered nodulation and SNA in most cases. The increase due to irrigation was the same in most instances under low or high N conditions. There was no indication that nodulation and N2(C2H2) fixation were more sensitive to fertilizer N in white bean than soybean. Fertilizer N application caused 10–20% increases in total N accumulation in each experiment, but seed yields were only increased by fertilizer N at the site with the least available soil N. N2(C2H2) fixation by white bean was much less than by soybean, yet seed yields of white bean were higher in two of the four trials. Yields in white bean appeared no more limited by available N than were yields in soybean.Key words: Phaseolus vulgaris, Glycine max, N2(C2H2) fixation, nodule development, seed yield
HARVESTING IRRIGATED ALFALFA IN THE ESTABLISHMENT YEAR IN SOUTHWESTERN SASKATCHEWAN
Authors: JEFFERSON P. G. , IRVINE R. B. , McELGUNN J. D.
Published: March 2010

Four alfalfa (Medicago sativa L.) cultivars, Beaver, Roamer, Dupuits and Alfa, were seeded on an alluvial clay loam soil in a randomized complete block design experiment in each of the 4 yr from 1976 to 1979 and again in 1981 at Swift Current, Saskatchewan. The plots were irrigated at a level to meet the evapotranspiration demand for maximum forage yield. The effect on future yields of harvesting once in the establishment year (approx. Aug. 15) was established by determining forage yields for 4, 4, 3, 2 and 2 yr subsequent to the establishment year, respectively. Establishment year harvesting reduced the subsequent yield of Beaver and Alfa cultivars in the 1976 and 1977 seedings. There were no significant effects in 1978, 1979 and 1981 seedings from establishment year harvesting. It was noted when significant yield reductions did occur in the post-establishment yields that the establishment year yield compensates and the total production of the stand is not affected. Roamer was superior to Beaver which was better than Alfa and Dupuits in winterhardiness at this location. Variation in the significance of establishment year treatments among seeding years indicated that establishment year management trials should be sequently seeded for at least 3 yr to evaluate management × environment interaction effects on perennial crops.Key words: Alfalfa, medicago, cutting, yield, winterkill
SEASONAL VARIATION IN CAMBIAL ELECTRICAL RESISTANCE AND ITS RELATION TO GROWTH IN TWO CULTIVARS OF PEACH
Authors: WISNIEWSKI M. , BOGLE A. LINN , WILSON C. L.
Published: March 2010

Seasonal trends in cambial electrical resistance (CER) of Loring and Redhaven peach trees (Prunus persica (L.) Batsch) were monitored with the use of a Shigometer. Three readings were taken on the main trunk of each tree periodically from early June 1981 through early December 1982. Individual records were maintained for each tree. One increment core was also taken from the trunk of each tree in late November 1982. The data suggested a relationship between CER and the onset of dormancy and a multiple regression analysis demonstrated a significant correlation between CER and growth, cultivar, and a growth-cultivar interaction (R2 = 0.61).Key words: Prunus persica, dormancy, growth, electrical resistance, peach
A MODEL SYSTEM FOR THE STUDY OF 2,4-D TRANSLOCATION IN LEAFY SPURGE
Authors: LINGLE SARAH E. , SUTTLE JEFFREY C.
Published: March 2010

A model system was devised to study the translocation of 2,4-D in leafy spurge (Euphorbia esula L.). The effects of rate of 2,4-D application, decapitation, and rate and pretreatment with ethephon on 14C-2,4-D translocation were studied. Rooted cuttings were obtained by rooting newly-developed axillary shoots in moist vermiculite for 4 wk. These cuttings were then placed in liquid nutrient medium for translocation experiments. Seven days after application, 50–60% of the 14C translocated from 14C-2,4-D treated leaves was found in the stem. The percentage of 14C that accumulated in the stem increased with increasing rate of 2,4-D application to 1 kg/ha. Up to 85% of 14C translocated to the root was released into the nutrient medium. Shoot decapitation 5 mm below the apex up to 4 days before 2,4-D application decreased 14C percentage in leaf tissue and increased 14C in stem and root. Foliar application of ethephon at 1 kg/ha resulted in a transient increase in the rate of ethylene evolution from shoot and root tissues, decreased the amount of 14C translocated to the root zone and increased the 14C in the leaves. Ethephon treatment of larger, vermiculite-grown plants also decreased 14C accumulation in the roots. These results indicate that the use of root cuttings is a convenient and reliable method for the study of herbicide translocation and plant growth regulator/herbicide interactions in leafy spurge.Key words: Translocation, 2,4-D, leafy spurge, Euphorbia esula L., plant growth regulator, ethephon
THE BIOLOGY OF CANADIAN WEEDS.: 67. Solarium ptycanthum Dun., S. nigrum L. and S. sarrachoides Sendt.
Authors: BASSETT I. J. , MUNRO D. B.
Published: March 2010

A descriptive key is provided for eight species of nightshade, Solanum spp., occurring in Canada. The biology for three of four closely related taxa, eastern black nightshade, Solanum ptycanthum Dun. ex DC; black nightshade, S. nigrum L.; and hairy nightshade, S. sarrachoides Sendt., weedy in various parts of the country, is discussed. American nightshade, S. americanum Mill., a name once applied to S. ptycanthum, is actually very rare in Canada and its biology is only partially discussed in this paper.Key words: Eastern black nightshade, black nightshade, hairy nightshade, weed biology, Solanum spp.
THE RESPONSE OF BUCKWHEAT TO PROTECTION BY TWO-ROW CORN WINDBREAKS
Authors: GUBBELS G. H.
Published: March 2010

Two-row corn (Zea mays L.) windbreaks were grown adjacent to buckwheat (Fagopyrum esculentum Moench.) to determine their effects on buckwheat yield and other agronomic characteristics. It was concluded that two-row corn windbreaks may improve buckwheat yields under certain environmental conditions, but the benefits may not be large enough nor consistent enough to warrant the additional cost and inconvenience of providing this protection.Key words: Buckwheat, corn, windbreaks
HEARTLAND BARLEY
Authors: THERRIEN M. C. , WOLFE R. I.
Published: March 2010

Heartland is a six-rowed spring feed barley (Hordeum vulgare L.) developed at the Agriculture Canada Research Station, Brandon, Manitoba. It has high yield, high test weight, good straw strength, and good disease resistance. This cultivar is primarily adapted to central Saskatchewan. Breeder seed is maintained by Agriculture Canada Research Station, Regina, Saskatchewan.Key words: Barley, Hordeum vulgare, cultivar description
FIELD PERFORMANCE AND MICROPROPAGATION OF A HARDY APPLE ROOTSTOCK CANDIDATE KSC-3
Authors: EMBREE C. G. , HICKS G. S.
Published: March 2010

Thirty Beautiful Arcade seedling apple rootstock selections (designated the KSC series) were established in a field trial with McIntosh and Red Delicious as scion cultivars. The selection KSC-3 promoted high vigor and with McIntosh both precocity and high yields. KSC-3 was successfully micropropagated using benzylaminopurine and indolebutyric acid in the shoot and root medium, respectively.Key words: Apple, rootstock, micropropagation
A DISORDER OF STORED CELERY
Authors: WALSH J. R. , LOUGHEED E. C. , VALK M. , KNIBBE E.
Published: March 2010

After storage at 1 °C celery (Apium graveolens var. dulce, L.) grown in the Bradford muck area of Ontario developed a black discoloration of the stalks which appeared outwardly in a striped pattern along the vascular strands. In cross section the vascular strands were discolored and appeared blackened. An atmosphere of 3% O2 plus 2% CO2 almost completely controlled the disorder. Ethylene and pre-storage treatment with sodium hypochlorite had little or no influence on the occurrence of the disorder but there was some indication of difference in cultivar susceptibility.Key words: Apium graveolens var. dulce. L., controlled atmosphere, ethylene, sodium hypochlorite, celery
COLD HARDINESS IN HEXAPLOID TRITICALE
Authors: LIMIN A. E. , DVORAK J. , FOWLER D. B.
Published: March 2010

The excellent cold hardiness of rye (Secale cereale L.) makes it a potential source of genetic variability for the improvement of this character in related species. However, when rye is combined with common wheat (Triticum aestivum L.) to produce octaploid triticale (X Triticosecale Wittmack, ABDR genomes), the superior rye cold hardiness is not expressed. To determine if the D genome of hexaploid wheat might be responsible for this lack of expression, hexaploid triticales (ABR genomes) were produced and evaluated for cold hardiness. All hexaploid triticales had cold hardiness levels similar to their tetraploid wheat parents. Small gains in cold hardiness of less than 2 °C were found when very non-hardy wheats were used as parents. This similarity in expression of cold hardiness in both octaploid and hexaploid triticales indicates that the D genome of wheat is not solely, if at all, responsible for the suppression of rye cold hardiness genes. There appears to be either a suppressor(s) of the rye cold hardiness genes on the AB genomes of wheat, or the expression of diploid rye genes is reduced to a uniform level by polyploidy in triticale. The suppression, or lack of expression, of rye cold hardiness genes in a wheat background make it imperative that cold-hardy wheats be selected as parents for the production of hardy triticales.Key words: Triticale, Secale, winter wheat, cold hardiness, gene expression
EFFETS D’UNE MORPHACTINE, LE CHLORFLURENOL IT-3456, SUR LA CROISSANCE ET LES ECHANGES GAZEUX DU TOURNESOL KRASNODARETS
Authors: LORD DANIEL , THERRIEN HENRI-P. , DUBÉ PIERRE-A.
Published: March 2010

A morphactin, the chlorflurenol IT-3456 (CFL), was applied to sunflower in order to evaluate its effects on growth, chlorophyll content and rates of photosynthesis, respiration and transpiration. At the concentrations used in the experiments (50, 100, 200, 300 ppm) growth inhibition and morphogenic effects of CFL were evident. However, this morphactin did not significantly decrease the fresh and dry weights of plants. The treatment at the lowest concentration of CFL (50 ppm) stimulated chlorophyll a and b synthesis while the other treatments had no effect. An open system to measure the gas exchanges of sunflower leaves was used to calculate the rates of photosynthesis, respiration and transpiration. Rates of these processes were not significantly affected by the application of different concentrations of CFL. It is suggested that the growth inhibition of plants treated with CFL owes more to an effect at the partition level of the new photosynthates rather than by an alteration of the photosynthesis mechanisms.Key words: Morphactin, chlorflurenol, photosynthesis, respiration, transpiration, sunflower
INFLUENCE DES RÉGIMES D’EXPLOITATION SUR LE RENDEMENT, LE PEUPLEMENT, LES RÉSERVES NUTRITIVES ET LA COMPOSITION CHIMIQUE DE LA LUZERNE
Authors: GERVAIS P. , BILODEAU M.
Published: March 2010

A 3-yr study on harvesting management applied to alfalfa (Medicago sativa L.) shows that a three-cut system, the last cut taken in October, yielded significantly more dry matter than a two-cut system. The latter system, however, gave a more uniform production throughout the years and maintained the stand at the highest level. Fall cuttings, taken at weekly intervals from the end of August to the end of September, reduced both the yield and the stand, the earliest cuttings being most harmful. October cuttings showed little effect on the productivity of alfalfa. The percentages of non structural carbohydrates stored in the roots on 1 November increased only slightly with the delay in taking the third cut in September. The accumulation of the food reserves was favored most by the two-cut system and the three-cut system with the last cut taken at mid-October. The influence of the harvesting regimes on the chemical composition of the forage is also discussed.Key words: Alfalfa, harvesting management, yield, persistence, chemical composition, food reserves
PRODUCTIVITY, QUALITY AND PERSISTENCE OF PERENNIAL RYEGRASS AS INFLUENCED BY CUTTING/FERTILITY MANAGEMENT AND PLOIDY
Authors: FAIREY N. A.
Published: March 2010

The agricultural value of four diploid and four tetraploid cultivars of perennial ryegrass (Lolium perenne L.) was investigated in the south coastal region of British Columbia under two intensities of cutting/fertility management, over three consecutive production years. The management systems were four cuts a year with fertilizer applied at an annual rate of 300:87:165 kg/ha of N:P:K (4C-300N) and eight cuts a year with 450:131:248 kg/ha of N:P:K (8C-450N). The 8C-450N management resulted in forage of greater nutritive value than the 4C-300N management, in terms of in vitro dry matter (DM) digestibility (716 vs. 681 g/kg) and nitrogen content (31.0 vs. 21.4 g/kg), but the DM content of the herbage was lower (168 vs. 181 g/kg). A greater annual yield of nitrogen was obtained from the 8C-450N management (278 vs. 201 kg/ha) but the annual yields of digestible DM were unaffected by the intensity of management and averaged 6410 kg/ha. Year-to-year fluctuations in the productivity and quality of the harvested forage were relatively small. Diploid cultivars tended to be more productive in digestible DM and nitrogen and higher in DM content than the tetraploid cultivars. However, the diploid cultivars were somewhat lower in in vitro DM digestibility and nitrogen content. It was concluded that the diploid cultivar Talbot and the tetraploid cultivar Barvestra were the most versatile and productive of the eight cultivars. They should be suited to both intensive rotational harvesting, by livestock or machine, and conservation for hay or silage. For strictly intensive rotational grazing or green-chopping purposes, the diploid cultivar Cropper should be equally as good.Key words: Grass, yield, quality, cutting management, nitrogen fertility, nutritive value
CRITICAL AUTUMN HARVEST PERIOD FOR ALFALFA IN THE ATLANTIC REGION BASED ON GROWING DEGREE-DAYS
Authors: BOOTSMA A. , SUZUKI MICHIO
Published: March 2010

Air temperature normals (1951–1980 period) were analyzed for over 200 locations in the Atlantic region to estimate spatial and temporal variations in the critical autumn period during which alfalfa (Medicago sativa L.) should not be harvested to allow plants to reach adequate winter hardiness by accumulating sufficient food reserves in the roots. Data are presented which show that the starting date of the critical harvest period could be estimated from the average date when 450 growing degree-days above 5 °C remain in autumn (F450). F450 compared well with starting dates determined experimentally in 3 yr of field tests at three locations in Ontario. F450 varied from before 10 Aug. in northwestern New Brunswick and parts of Newfoundland to after 4 Sept. in southwestern Nova Scotia. Annual differences in climate cause F450 to vary with a standard deviation of about 5–6 days at a given location. A zonation map describing spatial variation in the rest period was prepared as a general guide for cutting management.Key words: Alfalfa, Medicago sativa L., cutting management, winter survival, climate zonation
EFFECTS OF APPLYING INORGANIC FERTILIZER AND FARMYARD MANURE ON FORAGE PRODUCTION AND ECONOMIC RETURNS IN EAST-CENTRAL SASKATCHEWAN
Authors: HOLT N. W. , ZENTNER R. P.
Published: March 2010

Over a 4-yr period, annual application of inorganic fertilizer (IF) at 55 kg/(ha∙yr) nitrogen (N) plus 12 kg/(ha∙yr) phosphorus (P) and two times this rate or farmyard manure (FYM) at 11 or 22 tonne/(ha∙yr) significantly increased dry matter (DM) yields, nitrogen (N) and phosphorus (P) uptake and P content of alfalfa, bromegrass, crested wheatgrass and the grass-alfalfa combinations. Inorganic fertilizer produced larger yield increases of bromegrass, crested wheatgrass and their mixtures with alfalfa than FYM containing slightly more N and P. Each fertilizer form was as effective at increasing forage P, but IF increased the N content of crested wheatgrass or bromegrass by 0.1–0.5% more than a comparable rate of FYM. Utilization of P was 14–20% of that applied as IF and 6–13% of P applied as FYM. Utilization of N by the grasses was 44–52% for IF and 7–29% for FYM. At the relatively low levels applied, each fertilizer form increased bicarbonate-extractable soil P, but had no significant effect on total soil N, P or carbon. Based on forage market values that were related to the nutritional requirements of beef cattle, the net returns for the fertility treatments ranged from $121 to $261/ha for alfalfa, from $53 to $237/ha for grass-alfalfa mixtures and from a $48/ha loss to a $135/ha gain for grass only treatments. Application of IF was equally or more profitable than no fertilizer for all forage types. When FYM was priced on the basis of its total N and P contents, net returns for the 11 and 22 tonne/ha rates of FYM averaged $54/ha or 33% and $112/ha or 62% lower than those for the comparable IF treatments, respectively, and $25/ha or 19% and $65 or 39% lower than for the check treatments. When considering the alfalfa and alfalfa-grass treatments, the break-even value of FYM as a substitute for IF varied from $0 to $6/t of DM.Key words: Inorganic fertilizer, farmyard manure, forage yield, forage protein, economic worth of forage
VIRUS, ROOTSTOCK AND STRAIN EFFECTS ON THE LEAF NUTRIENT LEVELS OF McINTOSH APPLE TREES
Authors: WARNER J. , HEENEY H. B.
Published: March 2010

Major nutrient levels of leaves from two strains of virus-inoculated and uninoculated McIntosh apple trees on 10 rootstocks were compared from the 8th to the 12th year. Virus inoculation resulted in reduced leaf levels of N, P, K and Ca. Rootstock affected N, P, K, Mg and Ca some years, but only with K, Mg and Ca was the effect consistent over the 5 yr tested. The strain of McIntosh affected the Ca levels some years. Differences in leaf nutrient levels between years were highly significant. Interactions between year, virus and rootstock are discussed.Key words: Malus domestica, leaf nutrient levels, virus effects, Ottawa rootstocks
THE BIOLOGY OF CANADIAN WEEDS.: 68. Crataegus crus-galli L. sensu lato
Authors: DICKINSON T. A.
Published: March 2010

Crataegus crus-galli L. sensu lato (cockspur hawthorn) is one of the most readily identified Canadian hawthorns. It occurs frequently, and often in great abundance, on abandoned or poorly managed agricultural land in southern Ontario. These shrubs or small trees are difficult to remove and because of their thorns highly resistant to grazing. The weediness of cockspur hawthorn appears to be a function principally of reproductive characteristics (apomixis and self-fertility in abundant, unspecialized flowers each of which may develop into a fleshy fruit) that result in the production and dispersal of large numbers of seed annually (or biennially).Key words: Weed biology, cockspur hawthorn, Crataegus crus-galli, distribution
EFFECTS OF ETHEPHON ON FLUE-CURED TOBACCO AS INFLUENCED BY RATES OF ETHEPHON AND FERTILIZER APPLICATION AND SEEDLING AGE AT TRANSPLANTING
Authors: WALKER E. K.
Published: March 2010

Flue-cured tobacco seedlings at three ages were grown with three rates of fertilizer and the upper leaves were sprayed with 0, 50 and 100 mg per plant of ethephon. Ethephon treatment lowered the agronomic indices and produced leaves with a darker base color and less green (or more red) hues than the check treatment. Ethephon use also reduced green grades and increased grey, orange and mahogany grades, although undesirable grey was minimal for 50 mg ethephon per plant. An increase in desirable dark grades (orange and mahogany) was offset, for 100 mg ethephon per plant, by an increase in grey shades. The most consistent effects of seedling age were increased yield and crop returns and decreased lamina weight and grey grades with reduction in age. The most consistent effects of fertilizer regime were increased yield, crop returns and green grades, and decreased lamina weight with added fertilizer. Consideration of treatment effects indicated that rate of ethephon applied only to ripe tip and undertip leaves should be 50 mg per plant (3.2 L per ha) of Ethrel® or less. To minimize undesirable grades, it was found preferable to treat plants seeded during the second week of April, transplanted by June 1st and fertilized in sufficient amount to prevent premature yellowing.Key words: Agronomic indices, color grade, yield, economic return
A TECHNIQUE FOR IN SITU REMOVAL OF SUBTERRANEAN PLANT MATERIALS GROWN UNDER FIELD CONDITIONS IN CLAY-TILE MICROPLOTS
Authors: PHILLIPS D. R. , GAYNOR J. D.
Published: March 2010

A microplot system to study environmental factors on biological processes of perennial plants under field conditions is described. The plots consisted of clay tiles 35 × 35 × 70 cm placed vertically in the soil. A moveable base support with a steel rod attached through the center facilitated removal of the tile contents. Test vegetative material e.g. rhizomes, tubers, etc. was positioned within the tile during filling with soil. Top growth measurements could be made and tile contents extracted in predetermined increments of depth with a tripod and winch attached to the steel rod. The system was inexpensively fabricated from readily available materials.Key words: Root growth, root distribution
COMPARISON OF CANADIAN AND AMERICAN HARD RED SPRING WHEAT CULTIVARS
Authors: WATERER J. G. , EVANS L. E.
Published: March 2010

Comparisons were made between the yields and milling and baking properties of the Canadian hard red spring wheat cultivars Manitou, Glenlea, Neepawa, Benito and Columbus and the American cultivars Chris, Waldron, Butte, Coteau and Alex grown at six locations across Manitoba during 1982 and 1983. Glenlea consistently produced the highest grain yields but due to its low protein content performed poorly in the baking trials. Butte and Alex had good grain yields and excellent milling characteristics. Although they had low protein percentages their baking quality was excellent, indicating exceptional protein quality. Chris and Waldron had superior milling and baking characteristics but unacceptably low yields. Coteau appeared to be the best American cultivar tested, combining above-average yields with excellent milling and baking characteristics. Manitou and Neepawa had relatively low yields and only average milling and baking quality. Columbus appeared to be the best Canadian cultivar with acceptable grain yield, superior flour yield with excellent dough production and baking characteristics.Key words: Wheat quality, grain yields, milling quality, baking quality
DESICCATION OF SUNFLOWER WITH DIQUAT
Authors: GUBBELS G. H. , DEDIO W.
Published: March 2010

Diquat was applied at 0.3 kg (a.i.)/ha to sunflower (Helianthus annuus L.) at various stages of maturity in a 3-yr study to determine its effects on some agronomic and quality characteristics. The applications effectively hastened drying of the leaves and heads but stem drying was variable. Achene drying depended largely on the weather, with good advancement in some instances, but little advancement under cool, damp weather conditions. Advancement in harvest date by the treatments, taking into account both seed and plant drying, ranged from 0 to 26 days. Application made before physiological maturity reduced yield, oil content, 1000-achene weight, test weight and protein content of the meal. Fatty acid composition was also affected but to a lesser extent. There was no effect on achene germination. Applications made after the moisture content of the achenes had dropped below 45% did not appear to have any detrimental effects on achene yield or quality.Key words: Sunflower, desiccation, diquat
AGRONOMIC PERFORMANCE OF TRIAZINE-RESISTANT SINGLE-CROSS HYBRID OILSEED RAPE (Brassica napus L.)
Authors: GRANT IAN , BEVERSDORF WALLACE D.
Published: March 2010

The agronomic performance of eight triazine-resistant single-cross oilseed rape (B. napus L.) hybrids was evaluated. The yield of most of the hybrids was significantly greater than Atr-Regent; some of the hybirds demonstrated mid-parent heterosis, but none of the eight exhibited high-parent heterosis. In most cases the hybrids were intermediate to the parents for flowering date, plant height, lodging resistance, physiological maturity, percent oil and percent protein.Key words: Brassica napus L., oilseed rape, F1 hybrid, triazine resistance