bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of maternal plant environment and provenance on alpine bluegrass seed germination
Authors: Hermesh R. , Acharya S. N.
Published: April 2011

Adequate restoration of alpine disturbances requires seed material capable of germinating in high proportions and at a rapid rate. Germination of alpine bluegrass (Poa alpina L.) seeds of different provenances and produced under different environmental conditions was compared under uniform conditions of 16/8 h cycles of light/dark and 22/15 °C temperature. Seeds from nursery plots at the Alberta Environmental Centre, Vegreville, germinated in significantly higher proportions and faster than seeds from the same accessions grown in alpine environments. Alpine bluegrass clones grown in controlled environment chambers set at 22/15 °C and 15/8 °C light/dark with a 16-h photoperiod produced seeds with higher rates of germination and greater cumulative germination than seeds produced in an 8/1 °C regime. It is suggested that alpine blue-grass seeds with high germination percentage and rates are best produced under prairie nursery conditions.Key words: Alpine bluegrass, Poa alpina L., seed germination, maternal environment
Planting date effects on yield and quality of foxtail millet and three annual legumes
Authors: Twidwell E. K. , Boe A. , Kephart K. D.
Published: April 2011

Annual grasses and legumes offer potential as forages in the northern Great Plains region of the USA during late summer when perennial cool-season grass pastures are unproductive. The objective of this study was to evaluate the forage yield, in vitro digestible dry matter (IVDDM), and crude protein concentration of four annual species planted in May, June, and July at two South Dakota locations in 1989 and 1990. The species evaluated were cowpea (Vigna unguiculata (L.) Walp.), mungbean (Vigna radiata (L.) Wilczek), soybean (Glycine max (L.) Merr.), and Siberian foxtail millet (Setaria italica (L.) Beauv.). In 1989 cowpea, soybean, and millet produced similar yields at Highmore when planted in May, whereas in 1990 soybean had the highest forage yield of 8.3 t ha−1. Forage yields for the July planting were lower than those of the May planting, except for mungbean grown at Highmore in 1989 where the July planting produced 2.2 t ha−1 more forage than the May planting. Cowpea had significantly greater IVDDM than the other species for all three planting dates at Beresford in 1989, whereas at Highmore IVDDM for cowpea was not greater than that of mungbean for the May and June planting dates. Cowpea had the greatest crude protein concentration for all planting dates at Highmore in 1989, the greatest crude protein concentration for May and June planting dates at Beresford, and similar crude protein concentration to soybean for the July planting date. Millet, with the exception of the May planting at Highmore in 1990, consistently had lower IVDDM and crude protein concentrations than all three legumes each year at each location. The highest soybean forage yields at each location were always obtained from the May plantings. Cowpea forage yields were highest for the May planting at Highmore in 1989 and the June planting in 1990. Since cowpea often had higher forage yields, IVDDM, and crude protein concentrations than the other species it appears to be a viable alternative forage crop for this region.Key words: Annual forage legumes, millet, yield, quality
Comparative performance of mustard and canola in the Peace River region
Authors: Woods D. L.
Published: April 2011

Two mustard lines (Brassica juncea (L.) Czern) were compared with canola (B. napus L. and B. rapa L.) in the Peace River region. Mustard matured later than did B. rapa, and did not show a significant yield advantage over B. napus. Oil concentration was similar to that of B. rapa, and significantly below that of B. napus.Key words: Mustard, B. juncea, edible oil crop, comparative crop performance
Genetic stability in the Vitis vinifera L. cv. "Chardonnay", wild accessions of Vitis riparia Michx. and the Hybrid cv. "Seyval Blanc"
Authors: Subden R. E. , Carey K. , Krizus A. , Meiering A. G.
Published: April 2011

Using isozymes it was possible to measure the genetic stability of two cultivars and one wild species of Vitis. Comparisons of isozyme banding patterns were made between an indigenous species (Vitis riparia Michx. collected over a 1000-km range), 14 clones of an introduced long-established cultivar (Chardonnay) and vineyard accessions of a comparatively recently bred hybrid cultivar (Seyval Blanc). The isozymes acid phosphatase, glucose-6-phosphate isomerase and peptidase are polymorphic and were used as a basis for comparison. No within-cultivar differences were found for Chardonnay or Seyval Blanc but V. riparia exhibited genetic heterogeneity for each of the loci examined. Analysis of allele distributions supported the conclusion that there was no evidence of genetic isolation, that the 140 accessions of V. riparia represented one, apparently panmictic population and there was no introgression, in either direction, between V. riparia and the cultivars.Key words: Grape, genetic stability, polymorphic isozymes
Row cover and population density effects on yield of bell peppers in south coastal British Columbia
Authors: Gaye M. M. , Jolliffe P. A. , Maurer A. R.
Published: April 2011

Row cover and plant population density effects were studied at the Agriculture Canada Research Station, Agassiz, BC in 1988 and 1989. Bell pepper plants (Ace Hybrid) were transplanted into twin rows (0.45 m apart) on raised beds (1.8-m centers) at five population densities of 1.39, 1.85, 2.78, 5.56 and 11.1 plant m−2. For 7 wk in 1988 or 8 wk in 1989, subplots were either covered or not covered with slit clear polyethylene tunnels. A nonlinear regression model was used to define yield-population density responses. Row covers enhanced early and overall yields in 1988 and overall yield in 1989. Vegetative and reproductive yields (kg plant−1) declined with increasing plant population density. Yields were directly related to population density when measured on a land-area basis. Maximum fruit yield (7.9 kg m−2) was obtained at the highest population density. Treatment influences on fruit size were small and did not affect horticultural quality. An economic analysis showed that net returns were greatest with plants grown under row covers at the highest population density.Key words: Capsicum annuum L., field bell peppers, population density, row covers
Symptomless infection with Clavibacter michiganensis subspecies sepedonicus during tissue culture propagation of potato
Authors: Schuld B. A. , Harrison M. D. , Crane J.
Published: April 2011

Nodal cuttings of tissue cultured potato (Solarium tuberosum L. ’Sangre’) were inoculated with the bacterial ring rot (BRR) pathogen, Clavibacter michiganensis subsp. sepedonicus (Cms). Under commercial tissue culturing conditions, the pathogen persisted through as many as three micropropagation cycles, each consisting of production of a plantlet from an apical cutting. Infected plantlets did not develop BRR symptoms of leaf wilt or chlorosis. Signs of bacterial presence, cloudiness of tissue culturing medium or foliar lesions, were not present when the inoculum level was low, 5.0 × 102 cfu mL−1. A higher inoculum concentration (5.0 × 103 cfu mL−1) reduced plantlet height, but the lower concentration had no effect on height. Growth and viability of tissue from Cms-inoculated plantlets grown on Murashige and Skoog’s medium without sucrose, a source of carbon, were reduced compared to those grown with sucrose, but BRR symptoms were not induced at these inoculum levels. When transplanted to soilless potting medium, a basal portion of cycle 1 plantlets either died or produced a symptomatic miniplant, indicating that Cms survived during the growth of a plantlet into a miniplant. Nonsymptomatic miniplants were produced by portions of some cycle 2 and 3 Cms-infected plantlets, indicating that successive nodal propagation decreased the number of symptomatic miniplants. Bioassays of these nonsymptomatic miniplants were Cms-negative. Incubating plantlet tissue in Richardson broth for 14 d and visually observing for turbidity was not effective in detecting Cms in cultured potato tissue. Because phytopathogenic bacteria may persist in tissue cultures without causing symptoms, pathogen-specific testing of source plants and plant cultures is necessary to prevent transmission of bacteria to cultured stock and field-grown progeny.Key words: Potato shoot cultures, Solanum tuberosum L., Clavibacter michiganensis subsp. sepedonicus, medium with no carbon, bacterial persistence and detection, symptomless infection, Solanum melongena L.
Economics of fertilizer-N management for zero-tillage continuous spring wheat in the Brown soil zone
Authors: Zentner R. P. , Selles F. , Campbell C. A. , Handford K. , McConkey B. G.
Published: April 2011

Optimum use of fertilizer inputs requires consideration of factors that influence plant response and those that govern the decisions of producers. The response of spring wheat (Triticum aestivum L.) to soil water and fertilizer N (FN) was assessed in a 9-yr zero-tillage study conducted on a medium-texture, Orthic Brown Chernozem at Swift Current, Saskatchewan. These data were used to assess the economic merit and risk considerations of alternative fertilizer-N management systems when combined with snow-trapping to enhance soil-water reserves. The fertilizer-N systems included rates from 0 to 100 kg ha−1; spring versus fall applications, and deep banding versus surface broadcasting. Tall trap strips of cereal stubble (40–60 cm tall by 90–120 cm wide, spaced every 6 m and running perpendicular to prevailing winds) were used for snow trapping and compared with stubble cut at a uniform standard height of 15–20 cm. The results showed that optimum fertilizer-N rates (FN) varied directly with soil-water (SW) reserves (available water in 0–120-cm depth measured in spring) and the probability distribution for 1 May to 31 July precipitation, and inversely with soil N (SN) (NO3 N in 0–60-cm depth measured in the previous fall), ratio of fertilizer-N cost to wheat price, and the level of risk aversion held by producers. The optimum FNs were highest for spring and fall banding; they were 3–14 kg ha−1 lower for spring broadcasting and 7–22 kg ha−1 lower with fall broadcasting. The optimum rates increased 3.7–5.7 kg N ha−1 for each 10-mm increase in SW, with the higher rates associated with high SN. The FNs declined 5 kg ha−1 for each additional year that the land was cropped continuously. For producers seeking to maximize expected profit or those with low risk aversion, the optimum FNs were considerably higher than those recommended by the Saskatchewan Soil Testing Laboratory (SSTL). In contrast, the FNs for producers with high risk aversion were generally lower than those of SSTL. The SSTL-recommended rates were most appropriate for producers with medium risk aversion. The study found no single combination of timing and method of fertilizer-N placement to be superior in all cases. Spring and fall banding generally provided higher net margins than broadcasting fertilizer N when SW and wheat prices were high, whereas spring broadcasting was best when SW and wheat prices were lower. The economic benefit from snow trapping averaged $9–$32 ha−1 depending on FN and wheat price; however, there was little benefit or a small loss in some years when infiltration of meltwater was low or winter snowfall was minimal.Key words: Yield, fertilizer N, soil water, optimum rates, riskiness, profit
N2 fixation and dry matter and N accumulation in soybean lines with different seed-fill periods
Authors: Vasilas B. L. , Nelson R. L.
Published: April 2011

A positive relationship generally exists between the duration of seed-fill period (SFP) and seed yield in soybean, but exceptions have been reported. The objective of this research was to determine if differences in N2 fixation or N accumulation could explain inconsistent relationships between duration of SFP and seed yield in soybean. For this study, five experimental soybean (Glycine max L. [Men.]) lines were selected on the bases of differences in SFP and seed yield in previous experiments. The experiment was designed to compare lines differing in both SFP and seed yield, differing in SFP but not seed yield, and differing in seed yield but not SFP. Total N2 fixation, using 15N-dilution techniques; total N accumulation, using a semi-micro-Kjeldahl procedure; and total dry matter accumulation, including all vegetative material abscised before maturity were measured on these lines grown in a Flanagan silt loam (fine, montmorillonitic, mesic Aquic Argiudolls) in 1984 and 1985 at Urbana, IL. Mean dinitrogen fixed ranged from 36 to 76 kg ha−1 in 1984 and from 65 to 113 kg ha−1 in 1985. The percentage of the total plant N derived from fixation ranged from 17 to 35% in 1984 and from 32 to 48% in 1985. Statistically significant differences in seed yield were not detected in this experiment because of the high coefficient of variation associated with the small plot size. High N2 fixation was not related to duration of SFP or previous seed yield classification. Total plant N did not differ among these genotypes. For these soybean lines differences in duration of SFP and previous seed yield classification were not related to total N2 fixation or N accumulation.Key words: Glycine max, harvest index, N partitioning, N2 fixation, seed-fill period
Comparative effects of grain lentil–wheat and monoculture wheat on crop production, N economy and N fertility in a Brown Chernozem
Authors: Campbell C. A. , Zentner R. P. , Selles F. , Biederbeck V. O. , Leyshon A. J.
Published: April 2011

Low commodity prices and a desire by producers on the Canadian Prairies to reduce fertilizer-N inputs have resulted in a marked increase in grain lentil (Lens culinaris medikus) production. Many producers grow lentil in rotation with spring wheat (Triticum aestivum L.). A 12-yr study carried out at Swift Current, Saskatchewan, on an Orthic Brown Chernozemic silt loam was used to compare the N economy of four monoculture wheat rotations, of various rotation lengths and levels of N fertilization, with that of a wheat–lentil (W–Len) rotation. Except for continuous wheat (Cont W) receiving mainly P fertilizer, all systems received N and P on the basis of soil tests. Neither grain nor straw yield of the associated wheat crop was influenced by lentil in the rotation; but grain- and straw-N concentrations of the wheat in W–Len were increased compared with those of monoculture wheat. Average N content of straw was greatest for grain lentil and for wheat grown on fallow (F) (14.2 kg ha−1 yr−1), followed by wheat in W–Len (11.8 kg ha−1 yr−1) and by stubble-wheat of well-fertilized monoculture systems (F–W–W and Cont W (9.5 kg ha−1 yr−1)), and lowest for Cont W receiving mainly P (5.7 kg ha−1 yr−1). Nitrate N in the root zone (0–90 cm) in spring and at harvest was greatest under F–W, followed by W–Len and then by F–W–W and Cont W receiving N and P, and lowest for Cont W receiving mainly P. In the last 5 or 6 yr of study, there was a marked increase in the amount of soil-NO3 N found in the root zone under the W–Len rotation. This was accompanied by a similar increase in the apparent net N mineralized (estimated by N balance) during the growing season. Concomitantly, there was a gradual reduction in the fertilizer-N requirement for W–Len, indicating a cumulative enhancement of the N-supplying power of the soil, although estimates of the initial potential rate of N mineralization on samples taken in 1990 did not confirm this trend. We concluded that soil-testing laboratories may need to adjust fertilizer-N recommendations downward for producers that regularly use a 2-yr W–Len rotation. There was less NO3 N leached below the root zone of W–Len, probably because there was greater synchrony of N uptake in W–Len than in Cont W (N + P); this augurs well for the use of the W–Len rotation for sustainability.Key words: Crop rotations, pulse crops, N mineralization, N fixation, N leaching
Effect of triapenthenol plant-growth regulator on canola height, yield, side branches and pod density
Authors: Kirkland K. J.
Published: April 2011

A 3-yr field experiment was conducted at the Scott Experimental Farm to determine the effect of the growth regulator, triapenthenol, on the growth and development of Argentine canola (Brassica napus L.). Triapenthenol reduced plant height 25–45 cm under optimal growing conditions. Increases in yield, branches and total pods were observed. Application at the bud stage was more effective than earlier treatment in the rosette. It was concluded that triapenthenol application to canola could be a useful management tool, particularly under optimal growing conditions.Key words: Canola, growth regulator, RSW-0411, lodging
Hybridity and seed yield versus male sterility index (MSI) in pol CMS summer rape hybrid seed production plots
Authors: Pinnisch R. , McVetty P. B. E.
Published: April 2011

The degree of male sterility of pol A-lines, measured by a male sterility index (MSI) had significant linear relationships with both seed yield and hybridity of hybrid summer rape seed lots. Seed yield increased by 352 kg ha−1, while hybridity decreased by 6% per unit increase in MSI. A hybridity of 100% required an MSI of very nearly zero.Key words: pol CMS, Brassica napus, hybrids, MSI
Interactions of zinc with banded and broadcast phosphorus fertilizer on the concentration and uptake of P, Zn, Ca and Mg in plant tissue of oilseed flax
Authors: Grant C. A. , Bailey L. D.
Published: April 2011

Field experiments on four sites over 3 yr evaluated the effect of banded and broadcast applications of fertilizer P, with and without application of Zn on the tissue concentration and uptake by the plant of Zn, P, Ca, and Mg in oilseed flax (Linum usitatissimum L.). Residual effects of the P applications were also evaluated over five site-years. Banded applications of P tended to be more effective than either broadcast applications or residual P in increasing tissue concentration and uptake of P. Zinc application tended to decrease P concentration in the tissue where P levels were relatively high. When Zn was applied with banded P applications, it tended to reduce P uptake by the plant; when it was applied with broadcast P, it tended to increase P uptake by the plant. Changes in P uptake in response to Zn application generally reflected changes in dry matter production. When an increase in Zn concentration in the tissue or uptake by the plant occurred due to Zn applications, it was primarily when the Zn was applied with broadcast P fertilizer or where P had been broadcast the previous season. The increase in uptake of Zn generally reflected increased dry matter yield. Banded applications of P tended to produce lower tissue concentrations of Zn than did broadcast applications. Zinc concentration in the tissue also tended to be reduced by residual P from applications the previous season. Changes in Ca concentration in the tissue and uptake by the plant generally reflected changes in dry matter production. However, Mg concentration in the tissue and uptake by the plant were increased by P applications, particularly where P was banded. The increase in concentration in the tissue and uptake of Mg by the plant with application of P indicates that applications of P increase the ability of the plant to absorb Mg, presumably due to an effect on the absorption-translocation system within the plant. Key words: Flax, P placement, P, Zn, Ca, Mg
Brock soybean
Authors: Ablett G. R. , Tanner J. W.
Published: April 2011

Brock is a mid-Maturity Group I soybean (Glycine max (L.) Merr.) cultivar with excellent yield potential and lodging tolerance and with resistance to most races of phytophthora root rot caused by Phytophthora megasperma f. sp. glycinea (PMG) found in Ontario. Key words: Soybean, cultivar description
Profit summer rape
Authors: Rakow G. , Downey R. K.
Published: April 2011

Profit summer rape (Brassica napus L.), registered in 1989, is a canola-quality cultivar. It has very high seed oil content, is high yielding and has early to medium maturity. Profit is moderately susceptible to blackleg. Profit is well adapted to the B. napus growing areas of western Canada. Key words: Rape (summer), cultivar description
Prevention of shoot vitrification of strawberry micropropagated shoots proliferated on liquid media by new antivitrifying agents
Authors: Hdider Chafik , Desjardins Yves
Published: April 2011

Micropropagated strawberry (Fragaria × ananassa Duch. ’Kent.’) cultured for 4 wk in liquid proliferation media supported on cellulose plugs (sorbarods) developed a high rate of vitrification. This high percentage of abnormal plantlets was significantly reduced by the inclusion of two antivitrifying agents, EM1 and EM2, to the liquid medium. Virtually no vitrification occurred at 5 g L−1of EM1 or EM2. Shoots multiplied on liquid medium supplemented with 5 g L−1 of either EM1 or EM2 had significantly lower fresh weights and lower multiplication rates than on solidified agar medium (0.7%). EM2 produced better growth and proliferation than EM1 or liquid medium alone and was easier to use than EM1. Key words: Vitrification, antivitrifying agent, liquid medium
Root versus shoot measurements to evaluate recovery of Canada thistle (Cirsium arvense) after several years of control treatments
Authors: Donald William W.
Published: April 2011

Several methods were compared for estimating long-term control of Canada thistle [Cirsium arvense (L.) Scop.] after ending several years of herbicide treatment. Simple linear regression equations using shoot density m−2, numbers of adventitious root buds, or root fresh weight, measured in late summer after several years of herbicide treatment, were equally accurate in estimating Canada thistle shoot density m−2 in early June of the following year (R2 = 0.77–0.81). In contrast, shoot density m−2 measured in late summer estimated shoot density m−2 in late summer of the following year more accurately (R2 = 0.93) than did either root growth variable (R2 values = 0.80–0.83). Key words: Adventitious root buds, perennial weed, root
Zavitz soft white winter wheat
Authors: Hunt L. A. , Szlavnics Z. , Sheng Q.
Published: April 2011

Zavitz is a high-yielding, soft white winter, milling wheat adapted to the traditional wheat-growing areas of southern Ontario. Key words: Cultivar description, wheat (soft white winter)
The effect of foliar application of five plant growth regulators on the growth and yield of lowbush blueberry
Authors: Lewis John C. , Ju Hak-Yoon
Published: April 2011

The plant growth regulators, daminozide (2500 ppm), chlormequat chloride (1500 ppm), ethephon (500 ppm), mepiquat chloride (100 ppm), and paclobutrazol (1000 ppm), were foliar applied to sprouting-year and to first fruiting-year commercial lowbush blueberry (Vaccinium angustifolium Ait.). In sprouting-year blueberry, flower bud production was increased by paclobutrazol, resulting in significantly improved bloom and yield the following year. In fruiting-year blueberry, flower bud production was significantly increased by paclobutrazol in the year of application and resulted in improved bloom and yield in the following fruiting year. The effects of the other treatments on these parameters were in most cases not significant. Daminozide showed a significant bloom response with a sprouting-year application, but this did not translate into a yield response. Key words: Vaccinium angustifolium, plant growth regulators, paclobutrazol, flower bud production
Winter survival and yield of early-seeded winter wheat and triticale
Authors: Salmon D. F. , Baron V. S. , Dick A. C.
Published: April 2011

On the Canadian prairies, winter cereals such as rye (Secale cereale L.), triticale (X Triticosecale Wittmack L.) and wheat (Triticum aestivum L. EM Thell) have shown potential for forage production when spring-seeded as monocrops (WMC) or as intercrops (IC) and doublecrops (DC) in binary combinations with barley (Hordeum vulgare L.) or oat (Avena sativa L.). Producers are frequently tempted to overwinter the winter cereals for seed production in the second year. The current study evaluated the influence of forage harvest during the establishment year on the winter hardiness and seed production of winter wheat and triticale in the WMC, IC, and DC cropping systems. Clippings of the WMC and IC as well as planting of the DC were timed to correspond to jointing (DS1), boot (DS2), late milk (DS3) and grain harvest (DS4). Planting of the winter cereal after grain harvest (DS4) of the spring cereal simulated the conventional cropping system. All plots were clipped in late fall to remove aftermath prior to overwintering. Consequently treatments first clipped at DS1 received five clippings compared with DS4 which received only two clippings. Subsequent winter survival and grain yield of both winter species were reduced in the WMC and IC compared with DC treatments. However, increasing the frequency of clipping during the year of establishement in the WMC and IC improved grain yield and winter survival in the winter wheat compared with treatments receiving less frequent or no clipping. Less consistent results were observed for winter triticale. Overwintering spring-planted winter wheat and triticale is not a suitable means for seed production compared with conventional fall planting or reseeding to spring cereals. Key words: Spring cereals, winter cereals, winter survival
Effects of temperature and moisture stress on the germination of diverse common bean genotypes
Authors: Hucl P.
Published: April 2011

Seed germination of diverse common bean (Phaseolus vulgaris L.) genotypes was evaluated under controlled suboptimal conditions. Initially, 16 genotypes were tested at 12 and 16 °C. A subset of genotypes was subsequently germinated in distilled water or in polyethylene glycol solutions with water potentials (WP) of either −0.4 or −0.8 MPa at temperatures of 22, 26 or 34 °C. Genotypes did not respond consistently to low temperature stress, as indicated by significant (P < 0.05) crossovers in genotype ranking for percent germination from one temperature (12 °C) to the next (16 °C). Genotypes differed in median germination time (GT50) and estimated maximum germination rate. Genotypes with thinner seeds germinated better than wide-seeded genotypes under low-temperature conditions. Seed germination was reduced by 10 percentage units at a WP of −0.4 MPa and was virtually nil at a WP of −0.8 MPa. GT50 was reduced by 30% at 26 versus 22 °C but delayed by 80% when the WP was lowered from 0 to −0.4 MPa. Similarly, maximum germination rate increased with temperature but decreased with WP. Based on the germplasm evaluated in this study, common bean genotypes differ in seed germination response to temperature and moisture stress. Key words: Common bean, Phaseolus vulgaris L., germination, temperature, water potential
Clonal propagation of Pelargonium x hortorum through tissue culture: Effects of salt dilution and growth regulator concentration
Authors: Desilets Hélène , Desjardins Yves , Bélanger Richard R.
Published: April 2011

Different culture media were compared at the initiation and multiplication steps to develop a rapid production system for geranium (Pelargonium × hortorum) in vitro. Different salt dilutions of the Murashige and Skoog (MS) (1962) mineral medium were used in combination with different concentrations of 1-naphthaleneacetic acid (NAA) and 6-benzyladenine (BA) in order to optimize initiation of shoots of four geranium cultivars. The use of a MS basal medium with half-strength macrosalts supplemented with 0.11 μM NAA and 0.89 μM BA gave the best results in initiation. More than 40% of the apices initiated on this medium produced multiple shoots within a month. Subsequently, the effect of different concentrations of growth regulators was quantified by the mean of "shoot doubling time" evaluation. The shortest time recorded was 10.5 d for a theoretical production of 1 × 109 plantlets/apex/year. This is the first quantitative evaluation of geranium production in vitro. Geranium plantlets rooted easily on a half-strength MS medium without growth regulators. Acclimatization of geranium plantlets was characterized by high survival rates (94%) and the plants thus produced were phenotypically comparable to seed-derived plants. Key words: Geranium, micropropagation, shoot doubling time, in vitro
Comparison of crop management effects on spring barley cultivars grown on three soil types in southwestern Quebec
Authors: Smith D. L. , Ma B. L. , Leibovitch S. , Lussier S. , Maloba W. E.
Published: April 2011

There may be potential to increase grain yield and/or quality of barley (Hordeum vulgare L.) under the short crop-growing season conditions of Southwestern Quebec with intensive cereal management (ICM) practices similar to those used successfully in Europe. A field experiment was conducted for 4 yr (1987–1990) at the Macdonald Campus of McGill University to evaluate the applicability of ICM (140 kg N ha−1, 480 g a.i. ethephon ha−1, 70 g triadimefon ha−1 and 10-cm row spacing) vs. conventional cereal management (CCM) (70 kg N ha− and 20-cm row spacing) on spring barley. Four barley cultivars (Cadette, Joly, Laurier and Leger) were grown on three soil types: Bearbrook clay, St. Bernard loam and Chicot loamy sand. Grain yields of most cultivars were either unchanged or decreased 5–30% by ICM whereas Laurier occasionally yielded better under ICM than CCM. A general increase in spikes m−2 that resulted from ICM was largely offset by a reduction in grains per spike. Although ICM increased crude protein concentrations in grain and straw, use of 15N-labelled fertilizer showed a lower N recovery rate. The results indicated that yield response to ICM was inconsistent and was influenced to a large extent by prevailing weather and soil conditions. The ICM package tested is not applicable in this region. Key words: Conventional cereal management (CCM), intensive cereal management (ICM), 15N, nitrogen recovery, protein, soil type, spring barley
High R/FR HPS-pulses enhance earliness of flowering of exacum (Exacum affine Balf. F.) and geranium (Pelargonium × hortorum L. H. Bailey)
Authors: Tardif Michel , Dansereau Blanche
Published: April 2011

Four consecutive crops (Fall 1988, Winter 1989, Summer 1989 and Fall 1989) of exacum (Exacum affine Balf. f. ’Elfin’) and geranium (Pelargonium × hortorum L. H. Bailey ’Hollywood Star’ and ’Hollywood Red’) were grown in a greenhouse under three lighting treatments: ambient: 16-h high pressure sodium (HPS) lighting of 100 μmol m−2 s−1 between 0600 and 2200 h; and 16 h HPS-pulse lighting (45 s shut off, 90 s recharge) once every hour between 0600 and 2200 h. The growth index [(height × width)/2] of exacum plants was similar, regardless of the light treatment used. However the growth index of both geranium cultivars receiving HPS-pulse lighting was significantly less than those receiving the two other treatments. Exacum top dry weight was 225% greater under pulse lighting than under ambient light. During fall 1988, HPS-pulse lighting increased flower dry weight of Hollywood Red by 400% and 87% compared to ambient and HPS lighting, respectively. Key words: Exacum affine, HPS-pulse, Pelargonium × hortorum, photomorphogenesis, photosynthesis, photosynthetic photon flux
Wild mustard (Sinapis arvensis L.) competition with navy beans
Authors: Wall D. A.
Published: April 2011

Field studies were conducted in 1989 and 1991 to investigate the competitiveness of wild mustard with navy beans (Phaseolus vulgaris L.). Wild mustard growing in the crop row was highly competitive with beans sown in rows spaced 53 cm apart. Navy bean yields decreased with increasing wild mustard density. The greatest incremental yield losses occurred at weed densities of less than 20 plants m−2. Estimated yield losses at 20 wild mustard plants m, were 57 and 46% in 1989 and 1991, respectively. Wild mustard competition reduced seed test weight (g 0.5 L−1) less than 4% over the range of weed densities investigated. Key words: Navy bean ’Seafarer’, rectangular hyperbola, seed test weight, weed density, yield loss
Predicted and actual yield advance in a bi-parental and backcross-derived soybean population
Authors: Helms T. C. , Orf J. H. , Scott R. A.
Published: April 2011

Improved soybean [Glycine max (L.) Merr.] lines that include a plant introduction as one parent may be derived from a bi-parental (BP) or backcross (BC1) population. The number of BC1 families may be small in some instances because of a lack of successful crossing. The objectives of our experiment were to (1) compare the mean, genetic variance and distribution of lines from a BC1 population derived from only a few BC1 families with those from a BP-derived lines; (2) compare the BP and BC1 population mean with the mid-parent mean; and (3) evaluate the mean yield of the superior 10% of lines within each population. Two BC1F1 plants were selfed, and 75 random lines were derived from each plant. The mean yield, physiological maturity and plant height of BP-derived lines were greater than the mid-parent means. The genetic variance among BC1-derived lines was much smaller than among BP-derived lines. A utility function that combines mean yield and expected genetic gain identified the BC1 population as the superior population. Key words: Soybean, backcross, bi-parental, genetic gain
A model of expansion and senescence of individual leaves of field-grown maize (Zea mays L.)
Authors: Stewart D. W. , Dwyer L M.
Published: April 2011

Estimation of leaf area is a major component of plant growth models. In this study, a model was developed to calculate field-grown maize leaf area expansion and senescence on an individual leaf basis. The model began with an equation, based on cumulative growing degree-days from emergence, to initiate leaf area development. The model required daily values of maximum and minimum air temperature, solar radiation and precipitation, had essentially a daily time step with day and night modes, and could be run on commonly accessible computers (micros to mainframes). The objective of the development of the model was to assist plant breeders in optimizing leaf number and shape for adaptation to specific environments. Key words: Leaf area and number, temperature, phenological development
The effects of extraction rate and flour-sieve aperture on the properties of experimentally milled soft wheat flour
Authors: Dexter J. E. , Williams P. C. , Martin D. G. , Cordeiro H. M.
Published: April 2011

The effects of flour extraction rate and flour particle size (flour-sieve aperture) on the physical dough properties and cookie-making quality of soft wheat flour were examined during the development of a soft wheat experimental milling procedure. Soft wheats were milled to three extraction rates, and flour particle size was manipulated by changes in flour-sieve clothing. Physical dough properties, as measured by the farinograph and the alveograph, were weakly affected by milling procedure. However, cookie spread, cookie ratio and total cookie score exhibited strong negative relationships to both flour extraction rate and flour-sieve aperture. Soft wheats of different intrinsic cookie-making quality were ranked similarly by all milling procedures. Key words: Soft wheat, experimental milling, cookie-making quality, soft wheat quality screening
Winter wheat performance in various cropping systems in southern Alberta
Authors: Larney F. J. , Lindwall C. W.
Published: April 2011

A study was conducted in southern Alberta from 1984 to 1992 to determine the feasibility of growing dryland winter wheat (Triticum aestivum L.) in various systems with different crop rotations, tillage treatments and row configurations. Winter wheat was grown continuously and in 2-yr rotations with fallow, canola (Brassica campestris L.) and lentils (Lens culinaris Medic), under conventional, minimum and zero tillage. Each phase of each rotation was grown every year. Flax (Linum usitatissimum L.) replaced lentils after 4 yr of the study. After the first year, winter wheat after fallow out-yielded that in the other three rotations in all years. Zero tillage produced significantly higher yields than either conventional or minimum tillage in 3 of 8 yr. Paired-row spacing resulted in similar winter wheat yields in 4 yr and significantly lower yields than uniform-row spacing in 3 of the 7 yr in which this was compared. Extreme drought during much of the study period, which caused some crop failures, probably provided a worst-case scenario. We suggest, however, that winter wheat production in continuously cropped management systems in rotations with canola or flax is feasible. Zero tillage enhanced production, but paired-row spacing snowed no benefits under the soil and climatic conditions of this study. Key words: Winter wheat, crop rotation, conservation tillage, row spacing, drought, soil erosion
Composition and utilization in sheep of unwilted and wilted silages prepared from seeding year red clover (Trifolium pratense L.) cut at two maturity stages
Authors: Narasimhalu P. , Sanderson J. B.
Published: April 2011

Red clover (Trifolium pratense L.) cultivar Florex was seeded in May and cut at the vegetative stage on 5 August or at the 20% bloom stage on 25 August. The cut material was stored as unwilted silage or, after 26–30 h of field drying, as wilted silage. The silage types prepared from vegetative herbage were compared in the first feeding trial using 12 sheep per silage type. The silage types prepared from the 20% bloom stage herbage were compared in a second feeding trial using the 24 sheep from the first trial. Unwilted silage prepared from vegetative herbage contained less total-N and butyric acid, and more acid detergent fibre and ammonium-N than when this herbage was stored as wilted silage. Unwilted silage prepared from the 20% bloom stage herbage contained more total-N, soluble-N and ammonium-N and less propionic acid than wilted silage produced from herbage of the same maturity. All the silages contained low levels of volatile fatty acids and lactic acid due to restricted fermentation. Silage DM intake and digestibility in sheep were not affected by the type of silage produced within each stage of herbage maturity. Unwilted silage prepared from vegetative herbage provided lower intake, faecal excretion and retention of total-N in sheep than when this herbage was used as wilted silage. Silage types prepared from 20% bloom stage herbage showed no difference in total-N utilization in sheep. It was concluded that the seeding-year red clover harvested as unwilted or wilted silage in late August, can be used as a high quality buffer feed to meet forage shortfall due to severe winter kill. Key words: Red clover, silage, intake, digestibility, N retention
Bluesky red spring wheat
Authors: Clarke P. J. , Thomas J. B. , DePauw R. M.
Published: April 2011

Bluesky, red spring wheat (Triticum aestivum L.), combines high grain yield with a maturity about 1 d later than Neepawa. Bluesky has shorter and stronger straw than Glenlea. It is adapted to the Peace River and Parkland regions of western Canada. Key words:Triticum aestivum L., wheat (spring), high yielding, cultivar description
Effects of several organic fertilizers on growth of greenhouse tomato transplants
Authors: Gagnon Bernard , Berrouard Sylvain
Published: April 2011

An experiment was conducted to evaluate the potential of different organic wastes from the agri-food industry for growing greenhouse tomato (Lycopersicon esculentum Mill. 'Vision') transplants. The organic materials were thoroughly mixed with a peat–compost growing medium prior to transplanting. Meal from blood, feathers, meat, crab shells, fish, cottonseed and whey by-products produced the best growth, significantly increasing the shoot dry weight by 57–83 % compared with non-fertilized plants. Key words:Lycopersicon esculentum, organic fertilizer, peat, tomato, mineralization, nitrogen
Genetics of leaf-rust resistance in three spelt wheats
Authors: Dyck P. L. , Sykes E. E.
Published: April 2011

The inheritance of leaf-rust resistance was studied in three accessions of spelt wheat (Triticum aestivum ssp. spelta L.). Accession 7831 has a gene for seedling resistance to leaf rust that is linked with Lr33 (5.4 ± 1.05%), which is known to he on the long arm of chromosome 1B. This gene, which was either recessive or partially dominant, is designated Lr44, and because of its field reaction, should be useful in breeding rust-resistant wheats. Accession 7839 may also have this gene and an additional gene that in the seedling stage conditioned a type 2 infection to many races but little field resistance. Accessions 7831, 7839 and 7825 also have possibly in common a gene for adult-plant resistance. This gene, which did not give a high level of field resistance, was independent of Lr12, Lr13, Lr22, Lr34 and Lr35, other genes for adult-plant resistance. Key words:Triticum, wheat, leaf-rust resistance
Long-term manure application effects on nutrient uptake by barley
Authors: Chang C. , Janzen H. H. , Entz T.
Published: April 2011

Effects of long-term applications of high rates of animal manure on plant-availability of nutrients, especially micronutrients, have not been adequately addressed. Our study indicates high rates of P applied via manure do not suppress uptake of Cu and Zn by barley but, at higher than recommended manure rates, uptake of Ca may be inhibited, perhaps through increased salinity. Key words: Feedlot manure, micronutrients, Ca uptake
Freeze-thaw injury is enhanced by post-thaw leaching in water
Authors: Willison J. H. M. , Cheung C. H. , Zhang M. I. N. , Xiao X.
Published: April 2011

Turnip (Brassica rapa L.) root tissue was exposed to freeze-thaw stresses of −7, −9, -−11 and −19 °C. The post-thawed tissues were either subjected to leaching in deionized water for 2 h or left at 100% humidity. Tissue survival was then assayed by vital staining using modified 2,3,5-triphenyltetrazolium chloride (TTC) staining in 0.2 M phosphate buffer. Tissue survival was significantly lower for leached samples than for non-leached samples. It is concluded that freeze-thaw injury in plant tissues is enhanced by post-thaw leaching in water. The 0.05 M phosphate buffer commonly used for TTC staining also damaged freeze-thaw injured tissue. Key words:Brassica rapa L., 2,3,5-triphenyltetrazolium chloride (TTC), freeze-thaw injury, leaching
Variability in metribuzin tolerance among ruderal and agrestal populations of Solanum ptycanthum Dun.
Authors: Hermanutz L. A. , Weaver S. E.
Published: April 2011

Solanum ptycanthum Dun. is an annual weed of both agrestal and ruderal habitats in southern Ontario, which is the northern limit of its distribution. Plants of S. ptycanthum are introduced annually to the tomato-production areas of Ontario via the importation of tomato transplants from Georgia and North Carolina. The objective of this study was to test for genetic differences in tolerance to the herbicide metribuzin among agrestal and ruderal populations from southwestern Ontario and agrestal populations from Georgia and North Carolina. We compared growth responses among and within populations to low (0.4 kg a.i. ha−1) and high (0.9 kg a.i. ha−1) doses of metribuzin applied postemergence in greenhouse trials. Only the Ontario agrestal populations had been previously exposed to metribuzin. Ontario populations, regardless of habitat of origin, were significantly more tolerant of low and high doses of metribuzin than Georgia populations. Ruderal populations were more susceptible than Ontario agrestal populations to the higher dose of metribuzin. North Carolina seedlings were as tolerant as Ontario agrestal populations. These results suggest a genetic basis for tolerance differences unrelated to previous exposure. Overall intra-population variability in response to metribuzin was low, although the Ontario agrestal populations showed significant within-population variability in height and leaf growth in response to low and high doses of metribuzin. This suggests that the ability to respond to selection may differ among populations. Lack of significant levels of genetically based plasticity also suggests that herbicide-dependent selection within populations would be minimal. Key words: Eastern black nightshade, metribuzin, genetic variability, Solanum ptycanthum
Prairie crop yield estimates from modelled phenological development and water use
Authors: Raddatz R. L. , Shaykewich C. F. , Bullock P. R.
Published: April 2011

The feasibility of estimating average yields of spring wheat, barley and canola for Manitoba, Saskatchewan and Alberta, individually and collectively, from crop-specific model output routinely published in the Winnipeg Climate Centre's Agrometeorological Outlooks was examined. Statistically significant correlations were found between crop district/census division yields for 1988–1992 and modelled end-of-season crop water-use, and between these yields and the end-of-season ratios of water-use to water-demand and modelled days-to-maturity. Up to 69% of the observed variance in spring wheat yields could be explained by modelled agrometeorological variables. The best R2 values for barley and canola were 67 and 64%, respectively. The regression equations so derived were applied to 1993 model output and the resultant average crop district yield estimates for wheat, barley and canola, aggregated up to the provincial and the Prairie-wide levels, were compared with Statistics Canada's preliminary (i.e., July) and post-harvest (i.e., November) crop survey estimates and with yield estimates from the Canadian Wheat Board's Western Canada weather model. From these comparisons it was concluded that the Agrometeorological Outlooks can provide timely provincial and Prairie-wide estimates of average yields for these important Prairie crops. Key words: Crop water-use, crop water-demand, modelling, yield, wheat, barley, canola
Grain filling of R-nj color-selected maize strains divergently selected for kernel weight
Authors: Cross H. Z. , Mostafavi M. R.
Published: April 2011

Grain-fill characteristics in maize (Zea mays L.) affect yield by changing kernel weight. The objective of this study was to learn how divergent tandem selection for R-nj color expression and kernel weight affected rate of dry matter accumulation (RDMA), effective grain-filling period (EFPD), and lag phase duration (LAGP). We studied development of apical, mid-ear, and basal kernels in two genetic backgrounds. We derived 12 maize strains by tandem selection within each of two early-maturing synthetics. Mass selection of synthetics NDSF and NDSD for four cycles for high (HC), random (RC), and low (LC) R-nj color expression produced six substrains. Then, four cycles of divergent mass selection for kernel weight within each color-derived substrain produced 12 substrains for study. Using the 12 strains, we conducted field experiments using a completely random experimental design within each of 2 yr at Fargo, ND. Sequential kernel samples of individual ears within each strain provided data to estimate RDMA, EFPD, LAGP, and five-kernel weight (KWT). We sampled at 3- to 4-d intervals during the linear phase of grain-filling and at maturity. Selection for HC increased RDMA but tended to decrease EFPD compared to LC strains in both NDSF and NDSD. Selecting heavier kernels increased KWT of basal and mid-ear kernels by increasing RDMA. Direct and correlated responses to R-nj color selection were evident after four subsequent cycles of divergent tandem selection for kernel weight. Therefore, R-nj expression was not a temporary maternal effect. Kernel weight selection responses differed among the color strains and synthetics. Kernel weight seemed mainly determined by RDMA that was affected by selection for R-nj color expression and for kernel mass. Key words:Zea mays L., aleurone color, mass selection, correlation, yield components