bluuebunny/crossref_metadata_2025 huggingface dataset:
Drought-induced changes in free amino acid and ureide concentrations of nitrogen-fixing chickpea
Authors: Thavarajah Dil , Ball Rosalind A
Published: April 2011

The metabolic products of nitrogen (N) fixation in a legume can be amides or ureides. Chickpea (Cicer arientinum L.) is a cool-season legume which transports both ureides and amides from N fixation. Ureides are purine derivatives which are synthesized solely in the nodules. Drought-sensitive legumes accumulate ureides, but the regulation of these N fixation products during drought in chickpea is not yet known. The objectives of this study were (1) to measure the metabolic products of N fixation during drought and (2) to quantify the differences in N fixation among chickpea cultivars during drought by acetylene reduction activity under controlled environment conditions. Five chickpea cultivars were exposed to drought by soil dehydration. Plants were harvested at 1, 5, 10 and 15 d after drought and were analyzed for leaf and stem ureide concentrations and total N. In separate growth chamber experiments, N fixation was quantified daily. Leaf ureide and free amino acid concentrations were analyzed at 1, 5, and 15 d after drought. Drought increased ureide accumulation in drought-sensitive cultivars and decreased total N, alanine and asparagine concentrations over time. Drought-tolerant chickpea cultivars maintained ureide and amide concentrations during drought. Of the chickpea cultivars examined, Myles was the most drought tolerant and CDC Chico was the least. Further research on leaf ureides, alanine and asparagine concentrations would be valuable to determine if these metabolic products could serve as measures for screening chickpea germplasm for drought-tolerant N fixation. Key words: Ureides, N fixation, Asparagine, Acetylene reduction
Impact of high air temperatures on Brassicacae crops in southern Ontario
Authors: Warland Jon , McKeown Alan W , McDonald Mary Ruth
Published: April 2011

The yield patterns of many cool season vegetable crops were observed to be different from the gradual increase in yields that has been reported over time for corn and soybeans in Ontario. A study was conducted to determine if there was a relationship between yield and seasonal weather patterns for five vegetables (broccoli, cabbage, cauliflower, radish and rutabaga) in the family Brassicacae. The iterative chi-squared technique was used to identify correlations between daily temperature and marketable yield. Yields of all five of the crops showed some damage due to hot weather in August. For cauliflower, cabbage and rutabaga there was roughly a 10% yield loss for every 10 d that the temperature reached 30°C or above during the growing season. These results shed new insight into the mechanisms by which weather affects yield. Key words: Cabbage, broccoli, cauliflower, radish, rutabaga, yield, climate
Soybean cyst nematode: Challenges and opportunities
Authors: Winter Shawn M. J , Rajcan Istvan , Shelp Barry J
Published: April 2011

Soybean cyst nematode (SCN) is the primary pest responsible for yield losses of Glycine max. Management of SCN remains difficult in commercial soybean production due to the length of its biological cycle, frequent changes in population virulence, and ease of spread via infested soil. Effective management relies on crop rotation in combination with resistant cultivars, which have been derived from a limited germplasm base. Breeding for SCN resistance in soybean is difficult due to the quantitative nature of the trait, genetic variation within SCN populations, time required for phenotyping experimental soybean lines, and environmental factors affecting SCN reproduction. Quantitative trait loci associated with SCN resistance have been identified on 17 of the 20 soybean linkage groups, explaining 1–91% of the total phenotypic variation. Two major resistance genes, rhg 1 and Rhg 4, have been identified on linkage groups G and A2, respectively. Several minor resistance genes have been identified, but their importance varies with germplasm source and nematode race. Enhancement of SCN resistance in G. max may be achieved by interspecific hybridization with G. soja, the wild ancestor, or by engineering plants with candidate resistance genes such as Hs1pro-1. Key words: Genetic engineering, Glycine soja, soybean cyst nematode, molecular markers, resistance
Stubble management and microclimate, yield and water use efficiency of canola grown in the semiarid Canadian prairie
Authors: Cutforth H. W. , Angadi S. V. , McConkey B. G.
Published: April 2011

Standing stubble traps snow and creates a favorable microclimate, which increases yields in wheat (Triticum aestivum L.) and pulses [chickpea (Cicer arietinum L.), field pea (Pisum sativum L.) and lentil (Lens culinaris L.)]. Generally, the taller the stubble the greater is the effect on microclimate and yield. A field study using farm-scale seeding and harvesting equipment was conducted over four seasons (1999 to 2002) to assess the effect of stubble management on the microclimate, water use and seed yield of argentine canola (Brassica napus L. ‘Arrow’) in the semiarid prairie surrounding Swift Current. Tall (30 cm), short (15 cm) and cultivated stubble treatments were deployed in fall and in spring. An additional tall stubble treatment with extra fertilizer N (application rate recommended for the Black soil zone in the subhumid prairie) was included to assess the role of fertilizer in canola response to stubble management practices. The differences in wind velocity, soil temperature and solar radiation reaching the soil surface indicated significant modification of the microclimate by tall compared with cultivated stubble. Yields were highest from the tall stubble receiving extra fertilizer. Further research is needed to determine optimum fertilizer rates to maximize canola yields in the semiarid prairie. For treatments receiving equivalent rates of fertilizer, tall stubble increased seed yield of canola by about 24% and water use efficiency (WUE) by about 19% compared with stubble cultivated in the fall. Comparing between stubble treatments deployed on fields that overwintered as tall stubble and which received equivalent rates of fertilizer, tall stubble increased canola yield by about 16% and WUE by about 11% compared with cultivated stubble. Crop water use was not affected by stubble management so the increased grain production was due to increased WUE. Key words: Stubble height, microclimate, canola, yield, water use efficiency
Yield and quality of canola seed as affected by stage of maturity at swathing
Authors: Vera C. L. , Downey R. K. , Woods S. M. , Raney J. P. , McGregor D. I. , Elliott R. H. , Johnson E. N.
Published: April 2011

Swathing is an important canola (Brassica napus L.) harvest operation in western Canada. The determination of the optimum timing for this operation is worth considering, as premature swathing may lead to reduced seed yield and quality. Seed yield and quality of three canola cultivars (44A89, AC Excel and Ebony), as affected by two seeding dates and several harvest times (six or eight swathing times and one direct combined treatment) was investigated on a Black Chernozem silty loam soil at Melfort, Saskatchewan, Canada, during 1998, 2000 and 2001. Seed yield, weight, protein content (oil-free meal basis) and oil content generally increased with seed development and swathing time. Early seeding was more conducive to achieving higher seed yield, especially in good growing conditions, and resulted in heavier mature seeds with higher oil content. Seed oil composition also changed during seed development. The proportion of oleic (C18:1) and linolenic (C18:3) acids increased, while that of myristic (C14:0), palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0), linoleic (C18:2) and ara chidic (C20:0) acids decreased. The levels of the long chain fatty acids eicosenoic (C20:1) and erucic (C22:1) acids were unaffected. However, the overall amount of fatty acids synthesized (mg 100 seeds-1) increased as seeds matured. Swathing was advantageous over direct combining in preventing weather-induced shattering. Key words: Brassica napus, canola, fatty acid, oil, protein, seed development, seed quality, shattering, direct combining, swathing
Encore barley
Authors: Choo T. M. , Ho K. M. , ter Beek S. M. , Martin R. A. , Dion Y. , Rioux S.
Published: April 2011

Encore is a six-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 and good resistance to lodging. Encore performs well in Ontario and Quebec. Key words: Barley, Hordeum vulgare L., cultivar description, grain yield, lodging resistance
Haida-VR orchardgrass
Authors: Bittman S. , Acharya S. N. , Hunt D. E.
Published: April 2011

Haida-VR is a latematuring orchardgrass (Dactylis glomerata L.) cultivar with high levels of resistance to Cocksfoot Mottle Virus (CfMV) suited to silage and hay production in regions with moderate, temperate climate. The cultivar was developed at the Pacific Agri-Food Research Centre (PARC), Agriculture and Agri-Food Canada (AAFC), Agassiz, British Columbia (BC) in collaboration with AAFC Research Centre, Lethbridge, Alberta. In BC trials, Haida-VR yielded 3% more than the check cultivar Potomac without inoculation with CfMV and 21% better than the check when inoculated with the virus. In a southern Alberta trial, Haida-VR survived for 3 yr and yielded 3% better than a winterhardy check cultivar, Kay. Key words: Orchardgrass, Cocksfoot Mottle Virus resistance, Dactylis glomerata
Nitrogen nutrition of soybean in Brazil: Contributions of biological N2 fixation and N fertilizer to grain yield
Authors: Hungria Mariangela , Franchini Julio C , Campo Rubens J , Crispino Carla C , Moraes José Z , Sibaldelli Rubson N.R. , Mendes Iêda C , Arihara Joji
Published: April 2011

There has recently been concern in Brazil whether biological N2 fixation (BNF) is capable of meeting the increased N needs of newly released more productive cultivars, as well as doubts about the advantages of annual reinoculation of seeds. Forty experiments were performed over 3 yr in oxisols containing at least 103 cells of Bradyrhizobium g-1 in the State of Paraná, southern Brazil to estimate the contributions of BNF and of N fertilizer. The experiments were performed at two sites, Londrina and Ponta Grossa, under conventional (CT) or no-tillage (NT) systems, with two cultivars [Embrapa 48 (early-maturing) or BRS 134 (medium-maturity group)]. Treatments included non-inoculated controls without or with 200 kg of N ha-1, and inoculation without or with N fertilizer applied at sowing (30 kg of N ha-1), or at the R2 or R4 stage (50 kg of N ha-1). Compared with the non-inoculated control, reinoculation significantly increased the contribution of BNF estimated by the N-ureide technique (on average from 79 to 84%), grain yield (on average 127 kg ha-1, or 4.7%) and total N in grains (on average 6.6%). The application of 200 kg of N fertilizer ha-1 drastically decreased nodulation and the contribution of BNF (to 44%), with no further gains in yield. Application of starter N at sowing decreased nodulation and the contribution of BNF slightly and did not increase yields, while N fertilizer at R2 and R4 stages decreased the contribution of BNF (to 77%) and also yields. Estimates of volatilization of ammonia ranged from 15 to 25% of the N fertilizer applied, and no residual benefits of the N fertilizer in the winter crop were observed. The results highlight the economical and environmental benefits resulting from replacing N fertilizer with inoculation in Brazil, and reinforce the benefits of reinoculation, even in soils with high populations of Bradyrhizobium. Key words: Biological nitrogen fixation, Bradyrhizobium, inoculation, N fertilizers, ureides, soybean
Osmotic adjustment in leaves of Brassica oilseeds in response to water deficit
Authors: Levy D. , Fogelman E. , Itzhak Y. , Ma Q. , Turner D. W. , Cowling W.
Published: April 2011

The influence of water deficit on water content (WC), total soluble solids (TSS), osmotic potential (OP), sugar content and osmotic adjustment (OA) of expanded and partly expanded leaves of Brassica oilseeds was examined. Nine canola (B. napus) cultivars (Karoo, Monty, Pinnacle, Hyden, Mystic, Rainbow, Surpass 300, Surpass 400, Surpass 501), two doubled haploids, one from Karoo (KDH) and the other from Monty (MDH) and one line of Indian mustard (B. juncea, PI-81792) were grown under glasshouse and net-house conditions. Expanded wilted leaves of Karoo and Monty absorbed excessive amounts of water per dry weight upon in vitro rehydration compared with control non-stressed leaves, resulting in underestimation of OA calculated on the basis of the relative water content (RWC). Hence, estimation of OA based on water weight per leaf dry weight (WC) was preferred. Young expanding leaves maintained visual turgor for 6-7 d after withholding irrigation, while expanded leaves on the same plants ceased to regain turgor overnight. The young expanding leaves exhibited greater accumulation of TSS and, consequently, more negative OPs compared with expanded leaves. Maintenance of OA after irrigation and turgor recovery was evident in both expanded and expanding leaves. Although OA under drought and upon turgor recovery varied within cultivars in different experiments, outstanding OA capacity, in terms of both magnitude and stability, was identified in the cultivar Hyden and in the doubled haploid of Monty, indicating the potential to select for this trait as well as to exploit variability for OA through haploidization. Key words: Brassica oilseeds, drought stress, osmotic adjustment, haploid lines
Effects of four consecutive annual applications of elemental S and sulphate-S fertilizers on yield, S uptake and seed quality of wheat
Authors: Malhi S. S.
Published: April 2011

A field experiment from 1999 to 2002 was carried out near Tisdale in northeastern Saskatchewan on a S-deficient Gray Luvisol (Typic Cryoboralf) soil to compare the effects of elemental S and sulphate-S fertilizers on yield, seed protein, total S concentration, S uptake, and recovery of applied S in wheat (Triticum aestivum L.) and residual SO4-S in soil. Treatments were combinations of 10 and 20 kg S ha-1 rates applied in autumn and spring for two granular bentonitic elemental S fertilizers (ES- 90 and ES-95), one fertilizer containing both elemental S and sulphate-S (Agrium Plus), and ammonium sulphate, plus a zero-S control. The S fertilizers were surface-broadcast and all plots had a preseeding rotovation in spring to incorporate fertilizers into the soil. Seed (1 yr) and straw (3 yr) yield, seed protein concentration (1 yr), and total S concentration and S uptake in seed and straw (all years except uptake of S in seed in 2001 and 2002) showed significant response to S fertilization. Ammonium sulphate and Agrium Plus were generally more effective compared with the elemental S fertilizers, when there was a significant response to sulphate-S containing fertilizers. Autumn application of elemental S fertilizers was sometimes more effective than spring application, while an opposite trend was observed for sulphate-S containing fertilizers in some cases. The increase in S rate from 10 to 20 kg S ha-1 tended to increase the measured wheat parameters in many elemental S treatments, but for sulphate-S fertilizers the effect was less pronounced. The concentration of total S in seed and straw was relatively more responsive to S fertilization than yield and S uptake, particularly for seed. The effect of S fertilization on wheat was less pronounced in drought years, particularly on seed yield, suggesting that drought rather than S availability was limiting wheat growth. There was some build-up of residual SO4-S in the 0-60 cm depth of soil in many S fertilizer treatments after four successive applications, but there was little or no difference in soil SO4-S between elemental S and sulphate-S fertilizers. In conclusion, the results from four successive annual applications of elemental S and sulphate-S fertilizers in autumn and spring on the same area indicate that bentonitic granular elemental S fertilizers had comparatively less influence on wheat than granular sulphate-S fertilizers and further research to improve the effectiveness of these elemental S fertilizers is suggested. Key words: Elemental S, fertilizer, protein, seed quality, sulphate-S, wheat, yield
Fertilizer and rhizobial inoculant responses of chickpea on fallow and stubble sites in southern Alberta
Authors: McKenzie R. H. , Middleton A. B. , Bremer E.
Published: April 2011

Agronomic practices for chickpea (Cicer arietinum L.) production on the Canadian prairies are not well established. The objective of this study was to evaluate the impact of fallow on chickpea yield and response to rhizobia inoculation and fertilization. Field trials were conducted at nine fallow sites and nine stubble sites in southern Alberta over a 4-yr period (2000–2003). In the N experiment, N fertilizer was applied to rhizobia-inoculated and uninoculated desi (cv. Myles) and kabuli (cv. Sanford) chickpea at five N rates (0, 20, 40, 60 and 80 kg N ha-1). In the P experiment, P fertilizer was applied to desi chickpea at 0, 6.5 and 13 kg P ha-1. Growing season precipitation was well below normal during 3 of the 4 yr of this study, and fallow yields were more than double stubble yields. Desi seed yield increased 15.8 kg ha-1 for each millimetre increase in water use above a minimum requirement of 84 mm. Although nodulation of uninoculated chickpea was absent or very low at all sites, the benefits of inoculation were modest. On average, inoculation increased seed yield by 12%, seed protein concentration by 11%, and seed N yield by 24%. Inoculation responses were similar for fallow and stubble sites. Yield gains due to application of N fertilizer were also small at most sites, with no difference in yield gain between fallow and stubble sites. Yield benefits due to inoculation and N fertilization were often small because either moisture availability was low or soil N availability was high. Desi was more responsive to N fertilization than kabuli. Phosphorus fertilizer had a minimal impact on desi chickpea yield. Fallow had a large impact on chickpea yields, but did not affect rhizobia or fertilizer response. Key words: Cicer arietinum, yield, nitrogen, phosphorus, water use efficiency
Tsuru soybean
Authors: Poysa V. , Woodrow L. , Yu K.
Published: April 2011

Tsuru is a large-seeded tofu-type soybean [Glycine max (L.) Merr.] cultivar with elevated seed protein content developed at the AAFC Research Centre, Harrow, Ontario. Tsuru has yellow hilum and acceptable tofu processing quality for foreign and domestic markets. Key words: Glycine max (L.) Merr., soybean, cultivar description, tofu
Anthocyanins and nutrient components of saskatoon fruits (Amelanchier alnifolia Nutt.)
Authors: Ozga Jocelyn A , Saeed Asma , Reinecke Dennis M
Published: April 2011

The benefits of fruits and vegetables in human health have long been recognized. Part of the beneficial effects of these foods on human health has been purported to be due to various polyphenolic compounds that have radical scavenging and antioxidant activity. Saskatoon fruits (Amelanchier alnifolia Nutt.) are native to Western Canada and are an emerging North American fruit crop. The blue-purple coloration of mature saskatoon fruit, an important quality characteristic, is due to the presence of anthocyanins, which are a class of polyphenolic compounds that contribute to protection against human diseases. The objective o f this review is to summarize the research on anthocyanins, a potential nutraceutical, and other nutrient components in saskatoon fruits. In addition, management practices to increase anthocyanin content in the mature fruit are discussed. Key words: Amelanchier alnifolia, saskatoon, fruit quality, chemical composition, anthocyanins
Multiplexed PCR to screen for a major QTL carrying fusarium head blight resistance in Sumai-3 wheat
Authors: Matus-Cádiz M. A. , Pozniak C. J. , Hughes G. R. , Hucl P.
Published: April 2011

After the initial identification of microsatellites linked to economically important traits of interest, the additional investment to simplify the screening procedure for more routine use is of interest to plant breeders. The objective was to simplify an acrylamide gel based marker-assisted selection (MAS) method to facilitate high-through put screening for Qfhs.ndsu-3BS, a major quantitative trait locus carrying fusarium head blight (FHB) resistance in Sumai-3 wheat (Triticum aestivum L.). Method simplifications included incorporating the use of (1) 96-well DNA extractions, (2) multiplexed PCR reactions using microsatellite primers gwm493 and gwm533, and (3) agarose gels. Our modified FHB-MAS method was verified by screening six resistant (Sumai-3, ND2710, McVey, BacUp, HY644, and Alsen) and 52 susceptible parents and subsequently used to screen 5567 common wheat breeding lines developed from Sumai-3 derivatives. This simple and rapid method allows for the screening of 1000 lines per week, which can be used to skew segregating populations towards more resistant types and thereby advance primarily early and advanced generation lines that carry at least the major FHB QTL. Key words: PCR, Fusarium, microsatellites, gwm493, gwm533, Triticum
Identification of Trigonella accessions which lack antimicrobial activity and are suitable for forage development
Authors: Thomas J. E. , Basu S. K. , Acharya S. N.
Published: April 2011

Separate aqueous and ethanol extracts were prepared from the leaves and seed of 75 different Trigonella accessions and their ability to inhibit the growth of enteric bacteria and yeast was examined. No evidence of growth inhibition was observed, indicating that the Trigonella lines tested are suitable for forage development and animal consumption. Key words: Fenugreek, forage, antimicrobials, genetic diversity
AC Saltlander green wheatgrass
Authors: Steppuhn H. , Jefferson P. G. , Iwaasa A. D. , McLeod J. G.
Published: April 2011

AC Saltlander originated from seeds collected in Turkey by United States Department of Agricultural (USDA) scientists. Plants from these seeds were grown in a nursery near Logan, UT, where researchers at the USDA Forage and Range Research Laboratory selected desirable parents to obtain caespitose growth. In a collaborative project, selected germplasm of this natural hybrid was made available to the Semiarid Prairie Agricultural Research Centre (SPARC), Agriculture and Agri-Food Canada (AAFC) for salt-tolerance testing and improvement. A series of mass selection breeding cycles was conducted at Swift Current, where the resulting plants were evaluated for resistence to root-zone salinity, winter hardiness, and desirable plant morphology, including uniform plant colour, vegetative vigour, leafiness, seed-set, and freedom from plant pests. The progenies from each cycle were cloned, half of which were transported to the Agricultural Research Service Laboratory in Utah, and half intercrossed to develop AC Saltlander, a palatable forage with salinity tolerance equal to that of tall wheatgrass [Thinopyrum ponticum (Podp.) Lui & Wang]. Key words: Green wheatgrass, salt-tolerant forage, salinity, Elymus hoffmannii, perennial forage, reclamation grass
On selecting an appropriate multivariate analysis
Authors: Kenkel N. C.
Published: April 2011

The broad objective of multivariate data analysis in biology is to summarize associations among species (the dependent or response variables), and to elucidate species responses to one or more environmental factors (the independent or predictor variables). This objective is achieved by reducing the dimensionality of variable space to an efficient, low-dimensional summative model of the underlying data structure that reflects the coordinated response of species to environmental factors. While multivariate methods have proven indispensable for analyzing both experimental and survey data in the biological sciences, considerable confusion persists regarding the selection of appropriate analytical strategies. The selection of an appropriate analytical strategy, which includes important decisions regarding data transformation, variable standardization and methodological approach, should be based on fundamental considerations of statistical appropriateness, data structure, and study objectives. Unfortunately, past and more recent assessments of multivariate analytical strategies have been based largely on empirical models of questionable relevance. This empirical approach has led to misleading recommendations and erroneous generalizations regarding the relative efficacy of the available multivariate methods. This paper dispels these misleading recommendations and provides some general guidelines for selecting appropriate data transformations, variable standardizations and methodological approaches in the multivariate analysis of biological data. Key words: Ordination, canonical analysis, co-inertia analysis, principal component analysis, correspondence analysis, non-metric multidimensional scaling
Agronomic and economic responses to integrated weed management systems and fungicide in a wheat-canola-barley-pea rotation
Authors: Holm F. A. , Zentner R. P. , Thomas A. G. , Sapsford K. , Légère A. , Gossen B. D. , Olfert O. , Leeson J. Y.
Published: April 2011

Changes in tillage intensity and herbicide use can influence the incidence of weeds, insects and diseases, crop yields and economic returns. We examined the effects of six integrated weed management systems (with varying combinations of tillage methods, seeding rate, seeding date, time when weed control was applied, and annual fungicide applications on pest incidence, grain yield and quality, and economic returns for a spring wheat (Triticum aestivum L.)-canola (Brassica napus L.)-barley (Hordeum vulgare L.)-pea (Pisum sativum L.) rotation in the Dark Brown soils of the Moist Mixed Grassland Ecoregion of Saskatchewan. Herbicide use intensity was reduced without a significant increase in weed biomass in five of the six systems in most crops and years. The complete elimination of herbicides in one system resulted in significant crop yield losses. Certain insects were more prevalent in the cropping systems with early planting dates. Zero tillage systems produced higher yields, and yields generally declined as tillage intensity increased. For all crops, the high herbicide-zero tillage system produced the highest yields, whereas the lowest yields were obtained in the no herbicide-high tillage system. Management method had minimal impact on seed quality. Application of fungicide generally increased yields of barley, wheat and pea, but the increases were not sufficient to recover fungicide cost. High herbicide-zero tillage, medium herbicide-zero tillage, and low herbicide-zero tillage systems produced the highest net return and no herbicide-high tillage system the lowest net return, under all grain price scenarios. Key words: Agronomic, economic, tillage, herbicide, fungicide, weed management systems, weed, insect, disease
Greenhouse production of Echinacea purpurea (L.) and E. angustifolia using different growing media, NO3−/NH4+ ratios and watering regimes
Authors: Zheng Youbin , Dixon Mike , Saxena Praveen
Published: April 2011

Current field cultivation and wild-harvest methods for the medicinal plant Echinacea are struggling to meet the requirements for a high-quality, uniformly produced crop for human consumption. To help meet this challenge, the potential of using a greenhouse production system for Echinacea production was explored. Echinacea purpurea (L.) Moench and angustifolia DC. var. angustifolia plants were grown in three types of greenhouse production systems: (1) deep flow solution culture (D), (2) pots with either Pro-Mix (P) or (3) sand (S). Plants were irrigated with one of three nutrient solutions containing NO3−/NH4+ ratios of 7:1, 5:1 or 3:1, respectively. The plants grown in the Pro-Mix and the sand systems were either well-watered or subjected to periodical water stress. The results obtained after 12 wk of growth showed that Echinacea root production in the greenhouse systems was comparable with or better than that in the field. Based on root and total biomass production, the Pro-Mix system was the best production system for both E. angustifolia and E. purpurea. In most cases, the NO3−/NH4+ ratio did not have significant effects on the growth of either species. When effects were seen, however, higher NO3−/NH4+ levels generally resulted in greater leaf area, root and total biomass, and a higher root/shoot ratio. Mild periodic water stress did not affect the root/shoot ratio or the root biomass in either species. The application of a periodic water stress reduced leaf area of both species, but a reduction in total biomass was only observed in E. purpurea. Key words: Echinacea, greenhouse production, hydroponic production, medicinal plant, NO3−/NH4+ ratio, water stress
Yield potential of spring turnip rape synthetics and composite hybrids compared with open-pollinated commercial cultivars
Authors: Niemelä T. , Seppänen M. , Jauhiainen L. , Tulisalo U.
Published: April 2011

Yield potentials of spring turnip rape (Brassica rapa L.) synthetics and composite hybrids were compared with those of open-pollinated commercial cultivars during a 3-yr period (2000–2002). The trials included 16 synthetics and 25 composite hybrids derived from 22 different parent lines, as well as five open-pollinated commercial cultivars. All of the material tested had low erucic acid and glucosinolate contents and was well adapted for cultivation in southern Finland. The composite hybrids, which were tested for the first time in turnip rape, exhibited significantly higher seed yields than open-pollinated cultivars. The maximum commercial heterosis in seed yield was 18% in synthetics and 23% in composite hybrids. Both synthetics and composite hybrids showed better resistance to lodging than commercial cultivars. When studying the effect of commercial heterosis on seed yield, a high degree of variation was observed both within the synthetics and the composite hybrids. This result highlights the importance of testing parental combinations in turnip rape in order to find combinations that give the strongest heterotic effect. Key words: Turnip rape, Brassica rapa, synthetic, composite hybrid, seed yield, commercial heterosis
Canstar field pea
Authors: Bing Deng-Jin , Sloan Al , Conner Robert , Warkentin Tom , Xue Allen , Gan Yantai , Vera Cecil , Turkinton Kelly , Clayton George , Orr Denise , Gehl David
Published: April 2011

Canstar, a yellow cotyledon field pea (Pisum sativumL.) cultivar, has a semi-leafless leaf type, medium maturity, medium-sized and round seeds, good lodging resistance and high yielding ability. Canstar is resistant to powdery mildew and is adapted to the field pea growing regions of western Canada. Key words: Pisum sativum, field pea, powdery mildew resistance, cultivar description
Neural network modelling of fruit colour and crop variables to predict harvest dates of greenhouse-grown sweet peppers
Authors: Lin W. C. , Hill B. D.
Published: April 2011

Sweet peppers (Capsicum annuum L.) grown in the greenhouse have irregular yields. Modelling colouration of individual fruit could help growers predict the number of fully coloured peppers that will be ready to harvest within a routine harvest period. We monitored the red, green and blue colour intensities of developing pepper fruit via digital image processing. These colour measurements together with crop phenology and environmental variables were used as inputs into neural network (NN) models to predict days-to-harvest (D-to-H) for ind ividual fruit. When 18 inputs were evaluated, a typical “best” NN model needed only five of the inputs to predict D-to-H (range 0 to 28 d) for red peppers with a R2 of 0.79, a root mean square error (RMSE) of 3.4 d, and an average absolute error (AAE) of 2.5 d. D-to-H were more difficult to predict for yellow peppers, with the “best” model using eight inputs to achieve a R2 of 0.69, a RMSE of 4.4 d, and an AAE of 3.4 d. Light and temperature made little contribution to predictions of D-to-H. NN models with o nly three inputs (Julian day, nodal position of the target fruit and ratio of red:green intensities) could still make useful predictions of harvest maturity. For both red and yellow peppers, the R2 values of NN models were higher than the corresponding R2a (R2 adjusted) values derived from multiple linear regression models. It is concluded that NN have potential to assist greenhouse operators to predict D-to-H of sweet peppers. Key words: Greenhouse production, fruit, colouration, digital imaging, neural networks
Genetic variation in yield of five hybrids of sweet corn grown under poultry manure and nitrogen fertilizers and the presence of the nitrate reductase gene (Nia2)
Authors: Al-Otayk S. , Motawei M. I. , El-Shinawy M. Z.
Published: April 2011

Concern about nitrate (NO3−) accumulation in plants and its hazard to human and animal health has led to the investigation of the genetic variation in its accumulation in plants.Genetic variation in the productivity and nitrate content of sweet corn hybrids (Zea mays L.) when produced under five treatment combinations of chemical nitrogen fertilizer and poultry manure was investigated. In addition, the presence of the nitrate reductase gene (Nia2) in hybrids of sweet corn was investigated by PCR analysis. The chlorophyll content of leaves was higher with chemical fertilizer and the mixture of chemical fertilizer and chicken manure compared with chicken manure only. The highest grain yield was recorded in the hybrid Amera grown with chicken manure or the mixture of nitrate fertilizer and poultry manure. Moreover, gene-specific primer pairs for amplification of nitrate reductase revealed the presence of the nitrate reductase gene (Nia2) in hybrid Merit, which had the lowest grain nitrate content. Moreover, Merit only had one extra band (900 bp) indicating the Nia2 gene was controlled by co-dominant alleles. However, the presence of nitrate reductase gene (Nia2) alone did not explain nitrate content differences among corn hybrids. The work presented in this paper showed that PCR assays represent a sensitive tool for screening of sweet corn breeding material for the Nia2 gene although the presence of this gene does not alone explain nitrate content. Key words: Genetic variation, Low nitrate concentrations, sweet corn, nitrate reductase gene (Nia2), PCR
Yield, persistence, and nutritive value of autumn harvested tall fescue
Authors: Drapeau R. , Bélanger G. , Tremblay G. F. , Michaud R.
Published: April 2011

Tall fescue, harvested or grazed in autumn, may be a potential source of forage but little is known of the effect of a fall harvest or grazing on yield and nutritive value of tall fescue in the mid-north of eastern Canada (˜ 1400 growing degree-days). Three tall fescue cultivars (Courtenay, Kokanee, and Montebello) were submitted to 10 harvest management treatments (two dates of second harvest and five dates of third harvest) over 3 production years in the Saguenay-Lac-St-Jean region (QC). The cultivars Courtenay and Kokanee were more productive and persistent than Montebello. The annual DM yield decreased by an average of 15% between the first and the second production year and by an average of 35% between the first and the third production year; these decreases were greater (22 and 41%, respectively) when the third harvest was taken in early October. Increasing from 28 to 35 d the interval between the first and second harvests increased DM yield of the second harvest by more than 0.5 Mg ha-1, but caused a greater reduction in DM yield of the third harvest, primarily during the first 2 production years. Third-harvest DM yields of more than 4.0 Mg ha-1 were obtained in the first and second production years, while third-harvest DM yields varied from 2.5 to 3.0 Mg ha-1 in the third production year. With the delay of the third harvest in autumn, the concentration of crude protein decreased to 120 g kg-1 DM, the concentration of water-soluble carbohydrates increased to 150 g kg-1 DM, while that of acid detergent fibre changed very little. Tall fescue has a significant yield potential in late summer and early autumn in the mid-north of eastern Canada, primarily in the first 2 production years. However, harvesting or grazing tall fescue in the week preceding or following the first killing frost will reduce persistence and spring regrowth the following year. Key words: Lolium arundinaceum (Schreb.) S. J. Darbyshire, cutting management, cultivars, water-soluble carbohydrates
Agrinto Pinto Bean
Authors: Mündel H. -H. , Kiehn F. A. , Huang H. C. , Conner R. L. , Balasubramanian P.
Published: April 2011

Agrinto is a tall, partially upright pinto bean (Phaseolus vulgaris L.), with s hort vines, average seed weight of 340 mg, which was developed at the Agriculture and Agri-Food Canada (AAFC) Research Centre, Lethbridge, AB, in collaboration with the AAFC Research Station, Morden, MB. Agrinto is well adapted to wide-row irrigated produ ction of the Canadian prairies, with yields comparable to the check cultivar, Othello. Agrinto is resistant to both yellow and orange strains of the bacterial wilt, caused by Curtobacterium flaccumfasciens pv. flaccumfasciens (Hedges) Collins & Jones. Agrinto is resistant to race 73 of anthracnose [caused by Colletotrichum lindemuthianum (Sacc. & Magnus) Lams.-Scrib] and is moderately resistant to white mould [caused by Sclerotinia sclerotiorum (Lib.) de Bary]. Key words: Phaseolus vulgaris, pinto bean, cultivar description, bacterial wilt resistance, upright
Tristar fenugreek
Authors: Acharya S. N. , Blade S. , Mir Z. , Moyer J. R.
Published: April 2011

Tristar is an annual forage legume cultivar of fenugreek (Trigonella foenum-graceum). This cultivar was developed at the Agriculture and Agri-Food Canada (AAFC) Research Centre, Lethbridge, AB. Tristar biomass yield was 2 and 11% higher than the check cultivar Amber under dryland and irrigated conditions, respectively. This cultivar produced 26% more seed yield than Amber under irrigated condition in southern Alberta. Tristar will be an attractive alternative to alfalfa in short-term rotations as it produces as much biomass as two cuts of alfalfa and unlike alfalfa is bloat free and contains the steroidal compound diosgenin. Key words: Fenugreek, Trigonella foenum-graecum, annual legume, forage yield, forage quality
Genetic diversification of the Chinese wheat landrace Mazhamai as revealed by morphological characteristics, seed storage proteins, and microsatellite markers
Authors: Zhang Lingli , Li Hongjie , Wang Hui , Li Lihui
Published: April 2011

Chinese landraces of wheat (Triticum aestivum L. em Thell.) have had significant contributions not only to wheat production, but also to wheat improvement. Mazhamai is one of the most distinctive landraces, and has been used as a foundation parent in developing many outstanding improved cultivars in China. The objective of this study was to determine the genetic relationships of eight wheat landraces with the name Mazhamai, collected from wheat-producing regions with various geographical and microgeographic environments using morphological and agronomical traits, the composition of their gliadins and high-molecular-weight glutenin subunits (HMW-GS) and microsatellite markers. These homonymous accessions of Mazhamai differed, to some extent in their morphological and agronomical traits, gliadin composition, and microsatellite markers, but not for the HMW-GS and similar profiles for 52 of the SSR markers. This suggests that genetic variation must have occurred during the long-term growing of the Mazhamai accessions in various geographical regions. Furthermore, microsatellite analysis also revealed that the B genomewas more variable than the A and D genomes and chromosomes 2A and 2B were the most variable chromosomes among the Mazhamai accessions. However, chromosomes 1A, 1D, 2D, 5B, and 7A were conserved for the SSR loci used in the study. Key words: Wheat landraces, Mazhamai, genetic relationship, gliadin, glutenin, microsatellites
Phenotypic and genotypic identification of anthracnose resistance in kidney bean cultivars grown in western Canada
Authors: R. L. Conner Yang Dongfang, , Balasubramanian P. , Yu K. , Park S. J. , Penner W. C. , Yager L. M.
Published: April 2011

Five previously published molecular markers that are closely linked to the genes conditioning the resistance of common bean (Phaseolus vulgaris) to anthracnose (Colletotrichum lindemuthianum) and the seedling reactions to six anthracnose races were used to detect the presence or absence of four anthracnose resistance genes in seven kidney bean entries, five race differentials and two check cultivars. Under controlled environmental conditions, the kidney bean cultivar Napoleon and the navy bean Envoy were resistant against all of the anthracnose races and they appear to combine resistance genes Co-1 and Co-2 with either a third unidentified gene or is controlled by Co-12. The kidney bean cultivar AC Elk was only susceptible to race 31, which suggested that it carries genes Co-1 and Co-2, but molecular analyses only detected the presence of Co-1. Kidney bean cultivar GTS 401 was susceptible to all the races and no resistance genes were detected. Five other kidney bean entries, namely AC Calmont, Pink Panther, W K380, Red Hawk and Michigan Dark Red Kidney (MDRK), were only susceptible to races 2, 23 and 31. In these five kidney bean cultivars, the presence of gene Co-1 alone conferred the resistance to races 73, 89 and 1096. Genes Co-4, Co-42 and Co-5 were not detected with molecular markers in any of the seven kidney bean entries. Key words: Anthracnose (Colletotrichum lindemuthianum), disease resistance, gene identification, kidney bean (Phaseolus vulgaris)
13S2009 (Staccato™) sweet cherry
Authors: Kappel Frank , MacDonald Richard A , Brownlee Rob
Published: April 2011

13S2009 (Staccato™) is a very late maturing sweet cherry (Prunus avium L.) that has been released by the Pacific Agri-Food Research Centre (PARC-Summerland), Agriculture and Agri-Food Canada at Summerland, B.C. The release is part of the ongoing sweet cherry breeding program that began in 1936 (Kappel and Lay 1997). Staccato™ is the latest maturing cultivar released from PARC-Summerland and has very good fruit size and firmness. It was released to growers for commercial testing in 2000. Key words: Prunus avium, fruit breeding, cultivars
Tolerance of bare-root ornamental perennials to selected herbicides
Authors: Zheljazkov V. D. , Patterson K. , Parsons K. J. , Sampson G.
Published: April 2011

The market for ornamental perennials astilbe [[Astilbe japonica (Morr. & Dcne.) Gray], A. × arendsii, A. chinensis (Maxim.) Franch. & Savat.], stonecrop [Sedum roseum (L.) Scop.], hosta (Hosta fortunei Baker.), and daylily (Hemerocallis fulva L.) has expanded in Canada. We evaluated the tolerance of these ornamental species to selected herbicides applied preemergence and postemergence in Nova Scotia in 2002 and 2003. Napropamide, linuron, metribuzin, pendimethalin, metolachlor, pronamide, and oxyfluorfen may be used preemergence in hosta. Napropamide, pendimethalin, metolachlor, pronamide, and oxyfluorfen may be applied preemergence in all astilbe species. Linuron could be used preemergence in astilbe species japonica and arendsii, but not in chinensis. Napropamide, linuron, pendimethalin, metolachlor, pronamide, and oxyfluorfen may be suitable preemergence in both daylily and stonecrop. Bentazon, fluazifop-P, pendimethalin, pronamide, thifensulfuron, rimsulfuron, dithiopyr, and isoxaben can be used postemergence in hosta. Fluazifop-P, pendimethalin, pronamide, chlorimuron, thifensulfuron, rimsulfuron, dithiopyr, and isoxaben can be used postemergence in all three astilbe species. Bentazon, fluazifop-P, pendimethalin, pronamide, chlorimuron, rimsulfuron, dithiopyr, and isoxaben can be used postemergence in daylily. Bentazon, pendimethalin, pronamide, chlorimuron, nicosulfuron, nico-rimsulfuron, thifensulfuron, dithiopyr, and isoxaben can be used postemergence in stonecrop. Key words: Bare root perennials, herbicide efficacy, Astilbe, Sedum, Hosta, Hemerocallis, ornamentals, nursery crops
Evaluation of different nitrogen use efficiency indices using field-grown green bell peppers (Capsicum annuum L.)
Authors: Van Laura L
Published: April 2011

The effects of increasing nitrogen (N) fertilization on N use efficiency (NUE) and yield of green bell pepper were assessed in five field experiments over 2004 and 2005. These data were used to evaluate and contrast conclusions drawn from among 12 different NUE indices. In two diferent years (i.e., cool/wet vs. warm/dry), marketable yield response to N application was either positive or no response was observed. Total percent N in the fruit and shoot was lower in non-fertilized plants compared with plants grown in plots that received 70 or 210 kg N ha-1. There were considerable differences among locations in soil mineral N, yield, NUE, and plant N uptake and removal. For all eight fertilizer- and soil-based NUE indices assessed, NUE decreased as N application increased. However, for plant-based NUE indices, there was no difference in NUE values between N treatments. Thus, the interpretation and applicability of NUE depends on the goals of the research and the index used. Key words: Nutrient use efficiency, green bell peppers, harvest index, nitrogen, fertilizer, vegetable
Use of plant growth regulators to increase polyphenolic compounds in the wild blueberry
Authors: Percival David , MacKenzie Joanna L.
Published: April 2011

With increasing awareness of the antioxidant properties of the wild blueberry (Vaccinium angustifolium Ait.), more emphasis has been placed on d eveloping cultural management practices to enhance fruit polyphenolic levels and the use of processing byproducts as potential polyphenolic sources for the nutraceutical market. Trials were initiated in 2004 and 2005, with four plant growth regulators (methyl jasmonate, abscisic acid, riboflavin and Retain®) applied to maturing berries of the select clone Fundy at the Wild Blueberry Research Centre (Debert, NS). Berries were harvested 3 wk after treatment applications, with collections of green leaf tissues at harvest and red leaf tissues two weeks after harvest in 2005. Assessment of polyphenolic and anthocyanin levels within the berry and leaf tissues followed the Folin-Ciocalteu and pH differential methods, respectively. Overall, substantially higher levels of polyphenolic compounds were found within the leaf tissues, although anthocyanin content was highest in the berries. The application of methyl jasmonate resulted in a minor elevation in levels of bioactives within the harvested berry and red leaf tissues. This increase in bioactives occurred, however, at the expense of harvestable yields, with lower yield in plots treated with methyl jasmonate in 2004. Results thus suggest that the use of some plant growth regulators (PGR) may serve to increase bioactives, but their value must be assessed against a possible yield reduction. In addition, these studies indicate that leaf debris may provide a superior polyphenolic source for the nutraceutical market. Key words: Wild blueberry, plant growth regulator, anthocyanins, polyphenolics
Effect of nitrogen fertilizers on ammonia volatilization in wild blueberry production
Authors: Thyssen Gloria , Percival David , Burton David , Sanderson Kevin
Published: April 2011

Environmental losses of soil-applied N-fertilizers through ammonia volatilization were examined. Volatilization trials were established in the vegetative phase of wild blueberry production in Nova Scotia (NS) and Prince Edward Island (PE) in 2004 and 2005. Treatments consisted of no fertilizer (control) and N applications (35 kg N ha-1) of ammonium sulphate (AS), diammonium phosphate (DAP), urea (U) and sulphur coated urea (SCU). When compared with the control, results indicated significantly elevated volatilization rates for U (303% NS in 2004, 274% PE in 2005), SCU (273% NS in 2004, 205% PE in 2005) and DAP (178% PE in 2005). Results indicate that volatilization losses are significant, site specific and may contribute to reductions in nutrient availability. Key words: Nitrogen, wild blueberry, environmental losses, ammonia, volatilization