bluuebunny/crossref_metadata_2025 huggingface dataset:
Weather conditions associated with grape production in the Okanagan Valley of British Columbia and potential impact of climate change
Authors: Caprio J. M. , Quamme H. A.
Published: April 2011

An iterative χ2 method applied to 60 yr of records in the Okanagan Valley of British Columbia (1930–1989) revealed that the main climatic factor limiting grape production (Vitis spp. and Vitis vinifera L.) was low temperatures (critical value range, ≤–6°C to ≤–23°C) occurring during late October, November, December and February. Daytime temperatures ≤–9°C during late November and early December benefited grape production, probably because it prevented vine de-acclimation. Detrimental effects of precipitation during late October were probably associated with the early movement of Arctic fronts into the region. Beneficial effects of precipitation in the form of snow were observed in January. During the pre-harvest growing season, except for a 2-wk period in July, high temperatures (≥26°C) were associated with good production, probably because warm temperatures are required for flower bud initiation and development. In contrast, higher-than-normal temperatures were not beneficial to production during the harvest year. Detrimental effects of high temperature were observed during July of the pre-harvest year and July (≥32°C) and early August of the harvest year (≥28°C). During the growing season, rainfall was sometimes unfavourable for grape production under irrigation, either because of associated cool weather or greater disease occurrence. Both temperature and precipitation were greater in the last 18 yr of the study than the prior 36 yr, especially during the late winter and early spring. The anticipated climatic change appears to favour grape production in the Okanagan Valley. Key words: grape, climate change, heat stress, winter injury
Yield, herbage composition, and tillering of timothy cultivars under grazing
Authors: Kunelius H. T. , Dürr G. H. , McRae K. B. , Fillmore S. A. E. , Bélanger G. , Papadopoulos Y. A.
Published: April 2011

Timothy is widely grown for silage and hay in eastern Canada. The relative performance of timothy cultivars under grazing is not, however, well documented. This research determined dry matter production, herbage composition, and tiller characteristics of 34 timothy cultivars under two grazing schedules over 3 yr on the same plots. Several cultivars outyielded the standard cultivar, Farol (7.96 t ha-1), by up to 10% for the 3-yr mean. Richmond and Comtal were the highest-yielding cultivars (8.75 t ha-1) while AC Regal had the best relative yield persistence over the experimental period. Crude protein concentrations of cultivars ranged from 172 to 208 g kg-1 for early and 150 to 179 g kg-1 for late grazing. Neutral detergent fibre (NDF) concentrations ranged from 460 to 495 g kg-1 and concentration of acid detergent fibre (ADF) ranged from 241 to 270 g kg-1 among the cultivars in early grazing. Differences in NDF and ADF concentrations between early and late grazing schedules varied among the cultivars indicating a variable rate of change in fibre concentration. Farol, Timora, Promesse, and Comtal had greater tiller densities than most other cultivars while AC Alliance, Colt, and Winmor had below average tiller densities throughout the grazing season. The ratio between reproductive and vegetative tillers was higher early in the season, than later, but depended on the grazing schedule. The reproductive to vegetative tiller ratios covered a wide range in the third (2–54) and fourth (3–115) grazing periods. We conclude that yield and relative yield persistence of timothy cultivars under grazing varied greatly among cultivars. Tillering density of cultivars also varied but was not significantly related to cultivar performance under grazing. Key words: Timothy, Phleum pratense, grazing, composition, tiller
Response of two Canada thistle (Cirsium arvense) varieties to herbicides
Authors: Zand E. , Beckie H. J. , Myhre C. D. , Loeppky H. A.
Published: April 2011

Field observations suggested that control of Canada thistle variety horridumby hexazinone was greater than that of variety integrifolium. To confirm these observations, the response of these two varieties to hexazinone and 13 other herbicides was examined under controlled environment conditions. The tolerance of the variety integrifoliumto hexazinone was 40% greater compared with the variety horridum. Differences in shoot growth response between the two varieties were not detected from any of the other herbicides. Key words: Canada thistle, Cirsium arvense, variety horridum, variety integrifolium, hexazinone
Seed yield of successive synthetic generations in summer turnip rape
Authors: Falk K. C. , Woods D. L.
Published: April 2011

One Canadian turnip rapeseed cultivar and four canola-quality strains were used as parents to create 10 two-parent synthetics to assess the performance of successive synthetic generations and determine whether the planting of the Syn0 generation is an alternative to either the Syn1 generation or a single parental planting in summer turnip rape. Parents, as a group, yielded significantly less than Syn0s, Syn1s and Syn2s. The relative order of cultivar groups was consistent over environments (i.e., Syn1 ≥ Syn2 ≥ Syn0 ≥ parents). Key words: Turnip rape (summer), synthetic, Brassica rapa, Brassica campestris
Seed yield and components of alkaloid of meadow saffron (Colchicum autumnale) in natural grassland and under cultivation
Authors: Poutaraud and P. Girardin A.
Published: April 2011

Alkaloids extracted from meadow saffron seeds are used in numerous medicines. To test the influence of cultivation and climatic conditions on the production and the quality of meadow saffron seeds, we studied seed alkaloid yield on a natural site (grassland) and in a cultivated crop over several years. Seeds contained in capsules harvested before their dehiscence were dried and ground. The alkaloids of the extracts (colchicoside, demethylcolchicine and colchicine) were analyzed by high-pressure liquid chromatography. Seed alkaloid content was not influenced by year, inter-plant competition, or number of capsules per plant. Seed dry matter yield per plant, however, practically tripled in the cultivated crop due to an increase in the number of capsules per plant compared to the grassland. In the cultivated crop, 47% of fruiting plants produced two new plants (corms) every year. Four years after planting, this vegetative multiplication resulted in intraspecific competition, inducing a decline in seed yield per plant linked to a decrease in the weight of seeds per capsule. We were able to show that cultivated production of meadow saffron greatly increased dry matter and alkaloid yield per plant and per hectare, but that it could lead to the need to thin after several years. Key words: meadow saffron, alkaloids, colchicine, cultivation
DS Dominator field pea
Authors: Andersen L. , Warkentin T. , Philipp O. , Xue A. , Sloan A.
Published: April 2011

DS Dominator, a green cotyledon field pea (Pisum sativum L.) cultivar, was released in 2000 by Agriprogress Inc., Morden, Manitoba. DS Dominator has a semileafless leaf type, powdery mildew resistance, good lodging resistance, medium sized, round seeds, and good yielding ability. DS Dominator is adapted to the field pea-growing region of western Canada. Key words: Field pea, Pisum sativum L., cultivar description, powdery mildew resistance
The biology of Canadian weeds. 124. Hydrocharis morsus-ranae L.
Authors: Catling P. M. , Mitrow G. , Haber E. , Posluszny U. , Charlton W. A.
Published: April 2011

European frog-bit (Hydrocharis morsus-ranae L.), a free-floating, stoloniferous aquatic, is native to Europe and parts of Asia and Africa. It was discovered in Canada in 1932 in Ottawa, but earlier introduction is possible. By 1955 its North American distribution extended from Ottawa to Montreal. By 1980 it had extended southwest to Lake Ontario and northeast to Quebec City. Recently it has spread throughout much of the central and southwestern parts of southern Ontario, and further into northern New York and Vermont and eastern Michigan. The maximum rate of spread has been 15.6 km yr-1. Reproduction by seeds is rarely reported but vegetative reproduction is very important in spread and colonization. In the fall, turions separate from the plant, sinking to the bottom where they overwinter. In the spring, these turions grow into small floating rosettes. Extremely rapid stoloniferous growth during the summer months results in the formation of large masses of interlocking plants that diminish native submerged aquatic plant communities by reducing available light. It is also of importance in limiting water flow in irrigation systems and restricting water traffic, thereby hindering recreational activity. Management has been largely mechanical. Hydrocharis morsus-ranae is a food plant for several water birds, rodents, fish and insects. Key words: Hydrocharis morsus-ranae, weed biology, aquatic, Canada distribution, alien, European frog-bit, invasive spread
Second-crop N fertilization improves lowbush blueberry (Vaccinium angustifolium Ait.) production
Authors: Penney B. G. , McRae K. B. , Bishop G. A.
Published: April 2011

Most commercial blueberry growers follow a 2-yr pruning cycle because second-crop yield in a 3-yr cycle is usually too low for an economical harvest. Research was conducted to determine the extent to which second-crop production could be increased by applying fertilizer in the second-crop year. Treatments, consisting of factorial combinations of N (0, 60 kg ha-1), P (0, 26 kg ha-1), and K (0, 50 kg ha-1), were studied over two 3-yr burn-pruning cycles on a natural lowbush blueberry stand. Treatments were applied prior to, or shortly after, flower buds started to swell in the spring of the second-crop year. Nitrogen increased ripe fruit yield by 65% (3410 vs. 2070 kg ha-1) when compared with plots not previously fertilized with N, and by 43% (3410 vs. 2380 kg ha-1) when compared with plots previously fertilized with N. These results indicate that N might make the second crop economical to harvest. Phosphorus did not significantly affect yield, but K applied in combination with N in the second-crop year negatively affected production and Mg uptake. The increase in yield by N was due to more ripe berries resulting from a higher total (ripe + unripe) number of berries and hastened maturity that increased the percentage of ripe fruit. Reduced fruit abortion is suspected to be the reason for higher berry numbers. In contrast, the negative response to K applications with N was due to reduced total berry numbers. Key words: NK interaction, N × K interaction, potassium, nutrition, fertility, fruit abortion
Inheritance of hull pubescence and seed color in annual canarygrass
Authors: Matus-Cádiz M. A. , Hucl P. , Vandenberg A.
Published: April 2011

The availability of glabrous-hulled annual canarygrass (Phalaris canariensis L.) cultivars with yellow seed color may pave the way for developing this species into a food crop. The objective of this research was to study the inheritance of hull pubescence and seed color in annual canarygrass. A gametocide was applied to plants at Zadoks Growth Stage 42 to induce male sterility. CDC Maria, a glabrous-hulled and brown-seeded cultivar, was crossed with six pubescent-hulled, brownseeded annual canarygrass accessions and with CY193, a pubescent-hulled and yellow-seeded breeding line. In mono-hybrid crosses, segregation ratios of F2 populations were not significantly different from the phenotypic ratios of 3 pubescent-hulled: 1 glabrous-hulled for hull pubescence and 3 brown seeded: 1 yellow seeded for seed color. In the di-hybrid cross, a phenotypic ratio of 9 pubescent-hulled/brown seeded: 3 pubescent-hulled/yellow seeded: 3 glabrous-hulled/brown seeded: 1 glabrous-hulled/yellow seeded was observed. Glabrous-hulled and yellow seeded traits are each controlled by single recessive genes that segregate independently in annual canarygrass. Key words: Phalaris canariensis, canaryseed, inheritance, hull pubescence, seed color
Inheritance of scald resistance from barley lines 4176/10/n/3/2/6 and 145L2
Authors: Singh A. K. , Rossnagel B. G. , Scoles G. J. , Pickering R. A.
Published: April 2011

Scald incited by Rhynchosporium secalis (Oud.) J.J. Davis is an important fungal foliar disease of barley (Hordeum vulgare L.) that can cause significant yield and quality losses. While application of fungicides and/or cultural practices are possible control methods, the use of genetic resistance is a very desirable control strategy. Two New Zealand barley lines, 4176/10/n/3/2/6 and 145L2, derived from interspecific crosses, were evaluated in scald nurseries at Lacombe and Edmonton, AB, in 1998 and exhibited a high level of resistance. The objectives of this study were to further evaluate the level of resistance in these lines under western Canadian conditions and to study the inheritance of that resistance. Lines 4176/10/n/3/2/6 and 145L2 were each crossed with the scald susceptible cultivars CDC McGwire and RFLP Harrington. A scald screening nursery at Lacombe, AB, was utilized for disease testing in 1999 and nurseries at Lacombe and Edmonton, AB, were used in 2000. The F1 and F2 generations of all resistant/susceptible crosses were evaluated in 1999. One hundred F4:5 recombinant inbred lines from each cross were evaluated in replicated trials in 2000. Lines 4176/10/n/3/2/6 and 145L2 were resistant in all trials and resistant/susceptible populations segregated for single gene control of resistance in the F2 and F4:5 generations. Chi square analysis indicated that they possess a single dominant gene for resistance. These two lines should provide simply inherited sources of scald resistance for western Canada. Key words: Scald, barley, inheritance, resistance, Rhynchosporium secalis
The response of late storage cabbage and broccoli to applications of sulphur and calcium
Authors: McKeown A. W. , Bakker C. J.
Published: April 2011

Sulphur may become deficient in intensive vegetable production systems that rely on chemical fertilizers. Yield of cole crops in response to sulphur fertilization has not been evaluated under Ontario conditions. Since calcium is linked to clubroot disease and tipburn, the sulphur fertilizer source is an important consideration. Rates of sulphur and calcium were compared for effects on yield using Novacal (a prilled calcium sulphate product), calcium nitrate and potassium sulphate for 3 yr for cabbage and 2 yr for broccoli on both sand and loam soils. There appeared to be no difference in yield from fertilizer source of sulphur or calcium. Applications of sulphur increased yield of Huron late storage cabbage averaged over years and soil with a mathematical maximum occurring at 55 kg S ha-1. Soil tests indicated levels of approximately 13–19 µg g-1 for sulphur prior to treatment. Yield of cabbage increased proportionately to calcium application averaged over 3 yr. No effect of treatment was observed on broccoli. Thus, soil levels of sulphur were probably limiting for late cabbage but not for broccoli. Sulphur shortage or deficiency appears to exist for late storage cabbage grown in Ontario. Lack of response of broccoli and no calibrated soil test for either element suggest that crops have to be evaluated individually under field conditions for sulphur fertilizer requirements. Key words: Cabbage, broccoli, calcium, sulphur, nutrition, yield
Alert common bean
Authors: Mündel H. H. , Kiehn F. A. , Saindon G. , Huang H. C. , Conner R. L.
Published: April 2011

Alert is a high-yielding, semi-erect great northern common bean (Phaseolus vulgaris L.) cultivar. It was developed from a series of crosses at the Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia, on contract to the Agriculture and Agri-Food Canada (AAFC) Research Centre, Lethbridge, with cooperation from the AAFC Morden Research Station. Alert is well adapted to the eastern Canadian prairies, yielding significantly higher than the check cultivar, US1140, at 130% in the official Manitoba Dry Bean Co-operative Registration Trials. Alert is moderately resistant to white mold and resistant to races 1 and 15 of bean common mosaic virus (BCMV). It is susceptible to the alpha and alpha Brazil races of anthracnose, but resistant to the delta race. Key words: Common bean, Phaseolus vulgaris, great northern bean, cultivar description, high yield
Efficacy of Clonostachys rosea strain ACM941 and fungicide seed treatments for controlling the root rot complex of field pea
Authors: Xue A. G.
Published: April 2011

The efficacy of seed treatments with bioagent ACM941 (a strain of Clonostachys rosea), its formulated products GB116 and ACM941-Pro, and common fungicides for the control of pea root rot complex were examined in six field trials in western Canada from 1996 to 2000. The effects on seedling emergence, root rot severity, and yield varied among years. In trials 1 and 2 (1996–1997), none of the treatments significantly reduced root rot severity or increased yield. ACM941 + Thiram 75WP was the most effective treatment, increasing emergence by 17.4% and was significantly better than that of the untreated controls. In trials 3 and 4 (1997–1998), Apron FL alone and ACM941 + Apron FL were significantly better than the untreated control, increasing emergence by 6.2 and 7.7%, and yield by 10.8 and 11.5%, respectively. In trials 5 and 6 (1999–2000), AC M 941 and GB116 were equally the most effective treatments, increasing emergence by 11.5 and 12.2%, and yield by 8.2 and 6.3%, respectively. These effects were significantly greater than that of the untreated control, but not significantly different from those of Apron FL or Vitaflo-280. ACM941-Pro was developed and tested in 2000 only, and it increased emergence by 17.1% and reduced root rot severity by 29.6%. Key words: Bioagent, Clonostachys rosea, field pea, Pisum sativum, pea root rot complex (PRRC), seed treatment, fungicide
Application of seed-row potash to barley (Hordeum vulgare L.) grown on soils with high “available” potassium levels
Authors: Karamanos R. E. , Harapiak J. T. , Flore N. A.
Published: April 2011

Benefits of KCl application to cereals have been documented in Great Plains soils and have been attributed primarily to a response to the Cl- portion of this fertilizer either due to disease suppression or a Cl- deficiency. The practice of placing small amounts of KCl with the seed to avert any of these undesirable effects has been gaining momentum in western Canada. However, research on benefits from KCl fertilization of barley on high K soils in western Canada is limited. A large number of trials (115) were conducted from 1989 to 1998 on western Canadian prairie soils to ascertain the response of barley to seed-row applied KCl fertilizer. All soils contained K levels in excess of what is considered a critical level for obtaining a yield response to K due to K deficiency. Statistically significant yield increases with KCl application were obtained in 37 of 115 trials (32%). There appeared to be a strong link between the probability of obtaining a significant yield response to seed-row applied KCl, and barley cultivar and previous crop. Growing Harrington barley on barley stubble resulted in a grain yield increase due to KCl seed-placement 60% of the time. However, no clearly defined mechanism for the grain yield responses could be drawn based on the determined parameters, except that the majority of responses did occur under conditions that promote disease (e.g., disease susceptible cultivar, barley sown on barley stubble, etc.) and that the lower the soil “available” K levels in those instances, the higher the grain yield increase. Hence, it is hypothesized that K may play an indirect role in suppressing disease by increasing the overall health of plants. None of the assessed plant characteristics other than yield, i.e., days to maturity, kernel plumpness, protein and root rot infection, benefited from application of Cl- as either KCl or CaCl2. Key words: Chloride, cultivar, Harrington, disease, plant health, previous crop
Inoculant formulation and fertilizer nitrogen effects on field pea: Nodulation, N2 fixation and nitrogen partitioning
Authors: Clayton G. W. , Rice W. A. , Lupwayi N. Z. , Johnston A. M. , Lafond G. P. , Grant C. A. , Walley F.
Published: April 2011

Field pea (Pisum sativum L.) acreage has expanded rapidly in the past 10 yr in the Peace River Region of Alberta as well as western Canada. Understanding nitrogen dynamics of Rhizobium inoculants and applied N will provide farmers opportunities to improve N nutrition of field pea. Field experiments were conducted (a) to compare the effects of soil inoculation using granular inoculant, and seed inoculation using peat powder and liquid inoculants with an uninoculated check, on field pea nodulation and N2 fixation, and (b) to determine whether starter N is required by field pea to enhance N2 fixation. The effects of inoculant formulation on nodule number, N accumulation and N2 fixation were in the order: granular > peat powder > liquid = uninoculated. Field pea, from soil-applied inoculant, accumulated more N prior to and during podfilling than field pea with seed-applied inoculant. Fertilizer N application rates < 40 kg N ha-1 had no significant effects on biomass N at flatpod, indicating that starter N was not necessary. Application rates greater than 40 kg N ha-1 reduced nodulation, but the total amounts of N accumulated by plants did not vary. The close proximity of a highly concentrated band of N fertilizer had a greater impact on nodulation and subsequent N2 fixation than the residual soil N level. Under field conditions, soil-applied inoculant improved N nutrition of field pea compared to seed-applied inoculation, with or without applied urea-N. Key words: Granular inoculant, Pisum sativum, Rhizobium, inoculation, field pea, nodulation, N2 fixation
Canola response to boron in Canadian prairie soils
Authors: Karamanos R. E. , Goh T. B. , Stonehouse T. A.
Published: April 2011

Research on the boron (B) fertility and B fertilizer practices in the Canadian prairie soils is very limited. Soil testing methodologies, associated criteria and fertilizer practices developed in other parts of the world have been adopted. Use of hot-water-extractable (HW) B as an extraction of available B in western Canadian soils is thought to be a good, simple and efficient technique. A project was carried out in the three Prairie Provinces that included a number of aspects of B fertility. Hence, soils that according to established HW B criteria were deemed to be either deficient or marginal in B were selected, and a series of 22 trials in seven separate experiments was carried out. The effects of method of placement (broadcast and incorporation and seed-placement) and associated rates (0 to 5.1 kg B ha-1) as well as foliar application of common granular and liquid B products on the seed yield, plant tissue levels of young canola plants and oil content of canola seed were evaluated. There was no significant yield increase in canola seed yield in any of the 22 experiments, although levels of HW B as low as 0.15 mg kg-1 were encountered. There was a significant correlation between B in canola tissue at growth stage BBCH 30–39 and the rate of applied B; however, tissue levels were not significantly correlated to HW B levels in soil samples taken at the time of tissue sampling. Thus, soil properties, especially soil organic matter, play an important role in determining the fate of applied B in the soil-plant system. We were not able to calibrate the HW B soil levels against the relative yield of canola from 18 strip trials carried out in a preliminary survey and the 22 replicated trials. Thus, it is concluded that hot-water extractable B is not an effective diagnostic tool for determining the B status of western Canadian prairie soils. Key words: Hot-water-extractable B, plant tissue B, oil content, critical level, seed yield
An assessment of variation in foothills rough fescue [Festuca campestris (Rydb.)] in southern Alberta
Authors: May K. W. , Willms W. D. , Mengli Z. , Lysyk T. J.
Published: April 2011

The genetic diversity of native plants is thought to be an important consideration in the selection of appropriate material for reclamation. Field trials were c onducted in southern Alberta to determine the genetic variability, expressed through phenotypic and performance attributes, of several populations of foothills rough fescue [ Festuca campestris (Rydb.)] found in southern Alberta and south-central British Co lumbia. The objectives of this study were to determine the extent of genetic variability among plants of foothills rough fescue. Sixty-four plants from four populations were sampled in 1992, propagated vegetatively to produce clones for replicated trials a nd planted in four locations in 1993. Eleven plant characteristics, including phenotypic and performance variables, were observed from 1994 to 1997. Since the plants were grown in common environments, variations among them were assumed to be caused by gen etic differences. All variables were affected ( P < 0.05) by collection site and, with a few exceptions, test location, year and their two and three-way interactions. The most important factors specific to our objectives were collection site and its interact ions with test location and year. The rough fescue plants expressed differences ( P < 0.05) among populations for all selected traits but displayed considerable overlap in the range of values for all variables both within and among test sites. Therefore, wh ile the populations may be different, individuals within populations have common attributes that suggest sufficient genetic variability to allow successful establishment over a greater range of environmental variability than present at their origins. Resu lts from a secondary test suggest that selection pressure, induced by grazing, resulted in genotypes that were more winter-hardy. However, this observation needs further validation with a more robust test. Key words:
Allelic studies of new sources of scald (Rhynchosporium secalis Davis) resistance in barley
Authors: Singh A. K. , Scoles G. J. , Pickering R. A. , Rossnagel B. G.
Published: April 2011

The use of genetic resistance is a desirable disease management strategy for controlling scald (Rhynchosporium secalis Davis) in barley (Hordeum vulgare L.); thus, it is essential to screen for new sources of resistance. The objectives of this study were to test the novelty of scald resistance in two barley lines from New Zealand, 145L2 and 4176/10/n/3/2/6, relative to a number of resistance sources available to western Canadian breeding programs, and to determine the source of this resistance. 145L2 and 4176/10/n/3/2/6 were resistant in New Zealand and in scald screening nurseries in Alberta, Canada, in 1998. 145L2 was crossed with 4176/10/n/3/2/6 and with four local resistant lines to determine allelic relationships between 145L2 resistance, 4176/10/n/3/2/6 resistance and the resistance(s) in the local lines. To determine the source of the resistance, all H. vulgare L. lines in the pedigree of the New Zealand lines were evaluated in the same nurseries. The resistance gene in 145L2 was not allelic to that in 4176/10/n/3/2/6 or the other barley lines tested. All lines in the pedigree of the two New Zealand lines were susceptible, suggesting that their resistance is derived from unknown parents in their pedigrees. These New Zealand lines provide new sources of scald resistance that can be incorporated into western Canadian breeding lines. Key words: Barley, scald, resistance
AC Cruiser common bean
Authors: Park S. J. , Rupert T.
Published: April 2011

AC Cruiser navy bean (Phaseolus vulgaris L.) was developed at the Agriculture and Agri-Food Canada Greenhouse and Processing Crops Research Centre (GPCRC), Harrow, Ontario. It has good yield potential and a semi-determinate growth habit with a very up right plant type and medium-early maturity. The cultivar is recommended for areas in southwestern Ontario with 2650 or higher crop heat units. It has a low level of resistance to common bacterial blight. AC Cruiser was registered by the Canadian Food Inspection Agency Variety Registration Office (Registration no. 5360) on September 21, 2001. Key words: Phaseolus vulgaris, navy bean, cultivar description, plant type
Tolerance of annual forage legumes to herbicides in Alberta
Authors: Fraser J. , Moyer J. R. , Topinka A. K. , McCartney D.
Published: April 2011

The effects of ethalfluralin, trifluralin, and imazethapyr herbicides were assessed on stand density, visual injury and dry matter yield of annual forage legumes under irrigation. Results indicate that recommended rates o f either ethalfluralin or imazethapyr have potential for weed control in alfalfa, berseem clover, balansa clover, fenugreek, pea, and vetches. Key words:
Effects of duration of coverage with spunbonded polyester rowcovers on growth and yield of bell pepper (Capsicum annuum L.)
Authors: Waterer D.
Published: April 2011

Transparent rowcovers installed at transplanting and removed as growing conditions improve are commonly employed to promote development of warm-season vegetable crops. In regions with a brief and cool growing season, short-stature warm-season crops such as peppers could potentially benefit from being kept under the rowcovers for extended periods after transplanting. This study examined the influence of duration of coverage with spunbonded polyester rowcovers on vegetative growth, fruit yields and degree of fruit maturity of bell peppers over the 1999, 2000 and 2001 cropping seasons in Saskatchewan, Canada. Eight-week-old transplants of several cultivars of pepper were covered for 6 wk or 10 wk after transplanting or for the duration of the growing season. All growth and yield responses to the duration of coverage were consistent across the cultivars tested. In 1999, extending the period of coverage reduced aboveground vegetative growth of the crop, otherwise vegetative growth was not influenced by the duration of coverage. During the relatively cool 2000 cropping season, the duration of coverage had no effect on fruit yields or the proportion of the fruit that matured to red prior to frost. By contrast, in the warmer 1999 and 2001 cropping seasons, fruit yields declined as the duration of coverage increased. Excessively high temperatures interfere with fruit set in peppers. These results suggest that the risk of exposing the crop to excessively high temperatures may be increased by extending the period of coverage into the warmer periods of the growing season. Extending the period of coverage beyond the standard 6 wk also required additional labor and occasionally exacerbated problems with weeds and insect pests. Key words: Rowcovers, microclimate, ripening, pepper, Capsicum annuum
Response of field peas to phosphate fertilization
Authors: Karamanos R. E. , Flore N. A. , Harapiak J. T.
Published: April 2011

Canadian Prairie Provinces in general, and Saskatchewan in particular are major producers of peas worldwide. Individual provincial criteria for P application are considerably different from each other. Further introduction of new pea varieties and the adoption of direct seeding practices prompted us to re-evaluate these criteria. To this end, two experiments with field peas (Pisum sativum L. var. Carneval) were carried out between 1994 and 1998 at nine different locations in Alberta. The first experiment was carried out in 1994 and consisted of three trials with six rates of P (0, 4.4, 8.7, 13, 17.5 and 21.8 kg P ha-1) in the form of monoammonium phosphate (MAP) (12-51-0). To eliminate the impact of varying N rates along with P, a series of 21 trials and a uniform design that included five rates of P (0, 6.5, 13, 19.5 and 26 kg ha-1) in the form of triple super phosphate (0-45-0) and two methods of placement (seed placement or side banding) were subsequently carried out. There was a significant response to P application at all 13 sites of both experiments that contained 10 or less mg of a Modified Kelowna (MK) extractable-P kg-1 of soil. Side banding resulted in significantly higher yield in only three trials. Maximum average yield increase of 645 kg seed ha-1 was obtained with application of 19.5 kg P ha-1; it was influenced by soil texture as the magnitude of response was greater on loamy (535 kg seed ha-1) than on clay loam soils (285 kg seed ha-1). There was no significant yield increase in the trials that contained greater than 10 mg MK-P kg-1 soil. Reduction in plant population was more frequent as a result of seed placement (nine cases with P < 0.1) than side banding in both experiments. The impact of P fertilization on seed moisture was not consistent. The ability to side band or to seed with an increased seed bed utilization may fulfil the need for application of greater rates of P than the ones currently recommended for prairie soils. Key words: Seed placement, side banding, triple super phosphate, monoammonium phosphate
Corn heat unit variability and potential of corn (Zea mays L.) production in a cool climate ecosystem
Authors: Kwabiah A. B. , MacPherson M. , McKenzie D. B.
Published: April 2011

Recent interest in corn (Zea mays L.) production among forage producers in Newfoundland, Canada, raises questions of risk, scale and impact of seasonal heat accumulation for attaining maturity. The objectives of this paper were to present the results of corn performance in a short-term trial at three selected sites (St. John’s, Deer Lake and Stephenville), calculate corn heat unit (CHU) probability levels of these sites to assess the long-term risks, and determine CHU values of locations across Newfoundland to describe their suitability for corn production. Daily values of CHU were accumulated from the conversion of daily maximum (Tmax) and minimum (Tmin) air temperature for each location using the last day of 3 consecutive days in the spring with mean daily air temperatures (Tmean) ≥ 12.8°C as the starting date and the first date of a killing frost in the autumn (Tmin ≤ -2°C) or 30 September, whichever was earlier, as the ending date. Corn grown for silage at the three selected sites was within the desired level of 250–350 g kg-1 DM at 50% kernel milk line (R5.5) stage. Corn reached harvesting stage (R5.5) before the occurrence of a killing frost at Deer Lake and Stephenville. To protect seedlings against killing frost, mulching with transparent polyethylene film is recommended at St. John ’s. There was considerable year-to-year variability in CHU at each of the three sites. Differences in seasonal CHU for St. John’s were identified over two periods: from 1945–1989 and 1990–2001. The most recent period (1990–2001) has generally been warmer than the earlier period. A warming trend, as indicated by the CHU trends at the three sites, holds the prospect of some significant longer-term benefits for Newfoundland agriculture. Across Newfoundland, average (1956–1990) seasonal CHU accumulations (CHUave) based on STARTave and ENDend) ranged from 1686 at St. Lawrence to 2695 at Gander. Using the 80% probability (START80% and END80%) dates, the CHU80% ranged from 1486 at Port aux Basques to 2382 at Gander. The CHU values would help producers select what corn hybrid(s) to grow in their area. Overall, these analyses underline the potential for successful corn production in Newfoundland. Key words: Corn (Zea mays L.) maturity, corn heat units, cool climate region, 50% kernel milk line (R5.5), temperature
Microprojectile-mediated genetic transformation and regeneration of Chinese elm
Authors: Aziz A. N. , Sauvé R. J. , Zhou S. , Meng X.
Published: April 2011

A protocol for the genetic transformation and regeneration of Chinese elm ( Ulmus parvifolia Ja cq.) is reported. Cell suspension cultures were initiated from hypocotyls and were maintained on Murashige and Skoog (MS) basal semi-solid medium supplemented with varying concentrations of thiadiazuron (TDZ) and 1-naphthaleneacetic acid (NAA). Two week- old cell suspension cultures were bombarded with gold particles coated with plasmid harboring the Basta®resistance and â -glucuronidase genes. Elm cultures produced green calli within a month on selection media containing 20 mg L-1phosphinothrycin. These c alli were transferred to the same medium without the herbicide and were regenerated into shoots within 2 mo. The expression of uidA reporter gene in transformed elms was detected by histochemical analysis for â-glucuronidase activity. The presence of the Basta®resistance insert was demonstrated by polymerase chain reaction analysis. Key words:
Interrelationships among yield components of chickpea in semiarid environments
Authors: Gan Y. T. , Liu P. H. , Stevenson F. C. , McDonald C. L.
Published: April 2011

Chickpea (Cicer arietinum L.) seed yield can be increased by identifying and managing the key yield components. A field study was conducted in southwestern Saskatchewan in 1999 and 2000 to determine the direct and indirect effects of various yield components on chickpea seed yield . Both desi- and kabuli-chickpea were planted at the target plant populations of 20, 30, 40, and 50 plants m-2 on conventional summerfallow (CS) and no-till wheat stubble (NT). Path coefficient analyses revealed that seed yield for both chickpea classes largely depended upon pods m-2 and seed weight, with the kabuli crop having higher coefficient values than the desi. These relationships were stronger when the pulses were grown on CS than on NT. Seeds pod-1 had a negative effect on seed yield for the kabuli crop, but this negative effect was counterbalanced by a strong, positive effect of seed weight on seed yield. The total pod production of the desi crop depended on plants m-2 more than on pods plant-1, whereas the pod production of the kabuli crop relied equally on plants m-2 and pods plant-1. For both chickpea classes, mean seed weight decreased with prolonged vegetative growth period regardless of tillage environment. Seed weight was positively related to the length of reproductive growth and seeds pod-1 only when the pulses were grown on CS. Seed yield potential of desi chickpea would be increased by increasing plant population to produce more pods per unit area, whereas the seed yield potential of kabuli chickpea would be increased by shortening the period of vegetative growth, promoting the number of pods per plant, and increasing mean seed weight. Key words: Cicer arietinum, yield components, plant density, seed weight, canopy, path analysis
Island barley
Authors: Choo T. M. , Martin R. A. , ter Beek S. M. , Ho K. M. , Caldwell C. D. , Walker D. , Rodd V. , Dion Y. , Rioux S.
Published: April 2011

Island is a two-row, spring feed barley (Hordeum vulgare L.) cultivar developed by the Eastern Canada Barley Breeding Group, Agriculture and Agri-Food Canada. It has high yield, high test weight, high seed weight, excellent resistance to powdery mildew and moderate resistance to fusarium head blight. Island performs well in the Maritimes, Quebec, and Ontario. Key words: Barley, Hordeum vulgare L., cultivar description, high seed weight, powdery mildew, fusarium head blight
Early seeding dates improve oat yield and quality in the eastern prairies
Authors: May W. E. , Mohr R. M. , Lafond G. P. , Johnston A. M. , Stevenson F. C.
Published: April 2011

Demand for high quality oat (Avena sativa L.) for consumption by humans and race horses has increased, leading to increased oat production on the Canadian prairies. Little information exists on the best management practices for producing high-quality, high-yielding oat using direct seeding systems and cropping practices developed and adopted over the past 15 yr. The objective of this study was to determine the effect of early seeding on grain yield and quality of oat cultivars currently grown in the eastern prairie region. Four seeding dates and four cultivars were tested at Indian Head, Melfort, and Brandon over 3 yr. Moving the seeding date from mid-June to early May increased oat yield, seeds per panicle, kernel weight, test weight and plump seed by 76, 33, 10, 13 and 11%, respectively, when averaged across all locations and years. This increase in yield and quality was probably due to improved environmental conditions and a reduction in crown rust infection (Puccina coronata Corda). Crown rust has a larger effect on seed yield and quality as one moves east and south from Melfort, Saskatchewan, and as seeding was delayed from early May. Early seeding of oat decreases the risk of obtaining low yield and/or quality, and should be considered a best management practice for growing milling oats, especially in the southeastern prairies of Canada. Key words: Yield components, test weight, oat, Puccina coronata, lodging, plump seed, thin seed
Yield and insect injury in leafhopper (Empoasca fabae Harris and Empoasca kraemeri Ross & Moore) infested dry beans in Ontario and Colombia
Authors: Murray J. D. , Michaels T. E. , Pauls K. P. , Cardona C. , Schaafsma A. W.
Published: April 2011

Recombinant inbred lines derived from a cross between a leafhopper-susceptible bean (Phaseolus vulgaris L.), Berna Dutch brown and leafhopper-resistant selection EMP 419 were examined for resistance to the leafhopper species Empoasca abae (Harris) and Empoasca kraemeri Ross and Moore in Ontario, Canada and Colombia, South America, respectively. In both Ontario and Colombia there were significant positive correlations of visual injury scores with percent reductions in seed count, seed yield and seed weights. Leafhopper injury symptoms were significantly correlated with degree of stunting in Ontario, while only leaf burn scores were correlated with stunting in Colombia. Nymph counts were significantly and positively correlated with leaf curl scores in Ontario but not in Colombia, despite significant rank correlations of leaf burn scores and leaf curl scores between these locations. In a second experiment comparing the effects of E. fabae nymph infestations on set of 23 resistant and 5 susceptible recombinant inbred lines (RILs), the latter lines were infested by significantly fewer nymphs. Possible resistance mechanisms to E. fabae and E. kraemeri are discussed. Key words: Potato leafhopper, resistance insect, antixenosis, bean (navy), tolerance
Root characterization of three forage species grown in southwestern Uruguay
Authors: Gentile R. M. , Martino D. L. , Entz M. H.
Published: April 2011

Forage crops are widely grown in the mixed cropping system of southwestern Uruguay. There is renewed interest in the use of forages for soil improvement and carbon sequestration, but the root growth of forages has received little study. Field observations were made of the root systems of tall fescue (Festuca arundinacea Schreb.), alfalfa (Medicago sativa L.) and chicory (Cichorium intybus L.). Soil core samples were used to measure root count and biomass distributions to a depth of 1 m. Roots were detected to a depth of 1 m for all species, although half of the root biomass for each species was located in the top 20 cm of the soil. The distribution of root counts differed with the greatest number of root axes found above a depth of 20 cm for tall fescue and chicory, and below 20 cm for alfalfa. Key words: Carbon sequestration, perennial forages, subsoil, grasslands
Season of year effect on response of orchardgrass to N fertilizer in a maritime climate
Authors: Bittman S. , Zebarth B. J. , Kowalenko C. G. , Hunt D. E.
Published: April 2011

This study compared the response of harvests taken in May, June, August and September-October in terms of crop responses (yield, N uptake, and concentrations of crude protein and nitrate) to N fertilizer and residual soil nitrate and ammonium. Three trials were conducted in south coastal British Columbia in 1990–1992 to evaluate the response of an established sward of orchardgrass (Dactylis glomerata L.) to a range of N fertilizer rates. Both yields and daily crop growth rates were highest in cut 1, lowest in cut 4 and intermediate in cuts 2 and 3. For all four cuts, 95 and 90% of maximum yield was attained at about 136 and 82 kg ha-1 of applied N, respectively. Crop N supply from non-fertilizer sources ranged from 36 to 90 kg N ha-1, of which about 52% was attributed to nitrate present in the soil prior to growth and about 48% was N released from the soil, translocated from roots or deposited from the atmosphere. At 95% of maximum yield, crude protein concentrations ranged from 147 g kg-1 in the higher yielding cut 1 to 189 g kg-1 in cuts 2 and 4, while at 90% of maximum yield concentrations were 10 g kg-1 lower in each cut. Plant nitrate concentrations were close to levels that are toxic to cattle for the 95% target yield, but relatively safe at the 90% yield. The crop removed about 50 kg ha-1 more N when fertilized for 95% of maximum yield than for 90%, which translates to over 300 kg ha-1 more crude protein. High relative yield leaves behind more soil nitrate after harvest. The results suggest that the first cut should be managed for 95% of maximum yield with about 130 kg N ha-1. Cuts 2 and 3 should be managed for 90% of maximum yield, to avoid high plant nitrate concentrations, with 100–110 kg N ha-1. Cut 4 should be given no more than 50 kg N ha-1 for less than 90% of maximum yield because of the risk of residual soil nitrates. This study shows for the first time the benefits and disadvantages of applying N at different rates for each harvest over the growing season. Key words: Plant nitrate, nitrogen use efficiency, nitrogen recovery, Dactylis glomerata, relative yield, maximum economic yield
Cropping systems for annual forage production in northeast Saskatchewan
Authors: McCartney D. , Townley-Smith L. , Vaage A. , Pearen J.
Published: April 2011

Herbage production for silage and pasture production of annual species was investigated near Melfort in northeastern Saskatchewan. Barley (Hordeum vulgare L.) and oats (Avena sativa L.) were seeded as spring monocrops (SMC) and in binary intercrop (IC) mixtures with fall species including winter wheat (Triticum aestivum L.), fall rye (Secale cereale L.), winter triticale (X Triticosecale Wittmack L.), biennial Italian ryegrass (Lolium multiflorum Lam.) and annual Westerwolds ryegrass (Lolium multiflorum Lam.). Fall species were also seeded as monocrops (FMC). Silage Spring harvest occurred when barley (early-silage cut) and oats (late-silage cut) reached soft dough stage and again late in the autumn. An additional deferred grazing (DG) treatment containing each one fall species was harvested once in the autumn. Mean ranking of spring herbage silage yield was Oat-SMC (100%) > Oat-IC (91%) > Barley-SMC (83%) = Barley-IC (78%) > late-cut FMC (53%) > early-cut FMC (42%) (P ≤ 0.001). SilageSpring herbage yield of IC combinations was similar, but FMCs containing annual ryegrass were 26% to 34% (P ≤ .01) greater than other treatments. Crude protein content (g kg-1) was 14 to 35% higher (P ≤ 0.001) in IC systems than the corresponding SMC. Neutraleutral detergent fibre (NDF) and acid detergent fibre (ADF) content (g kg-1) of barley based systems was 15 and 22% lower (P ≤ 0.001) than those with oats. Ranking and relative productivity for fall pasture was DG (100%) > early-cut FMC (67%) > late-cut FMC (49%) > Barley-IC (30%) > Oat-IC (24%) = Barley-SMC (14%) (P ≤ 0.001). Cropping systems that contained no spring cereal produced 2.37-fold higher (P ≤ 0.001) fall pasture yield than those with spring cereals. Among FMCs, ICs and DG systems, mean yield of ryegrass treatments were generally higher (P ≤ 0.05) than that of fall cereals. Key words: Annual forage, deferred grazing, intercrop, monocrop
Macbeth flax
Authors: Duguid S. D. , Kenaschuk E. O. , Rashid K. Y.
Published: April 2011

Macbeth, a medium-late maturing oilseed flax (Linum usitatissimum L.) was released in 2002 by Agriculture and Agri-Food Canada, Morden Research Station, Morden, Manitoba. This cultivar has high oil content, high oil quality, large seed size, very good lodging resistance and high yield when seeded in all the soil zones of the Canadian prairies as compared to Flanders. It is immune to current North American races of rust caused by Melampsora lini (Ehrenb.) Desmaz,, moderate resistance to wilt by Fusarium oxysporum Schlecht. f. sp. lini (Bolley) Snyder & Hansen and moderate resistance to powdery mildew by Oidium lini Skoric. Key words: Flax, oilseed, Linum usitatissimum L., cultivar description