bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid separation and characterization of grain water-soluble proteins in bread wheat cultivars (Triticum aestivum L.) by capillary electrophoresis
Authors: Wang Ai-li , Pei Yu-he , Li Xiao-hui , Zhang Yan-zhen , Zhang Qian , He Zhong-hu , Xia Xian-chun , Appels Rudi , Ma Wu-jun , Huang Xiu-Qiang , Yan Yue-ming
Published: April 2011

Water-soluble (WS) proteins in wheat grain are considered to represent the suite of biologically active enzymes and enzyme inhibitors in the grain. In this study, a rapid capillary electrophoresis (CE) method for WS protein separations was developed using untreated fused-silica columns and an acidic phosphate-glycine buffer system. In order to optimize the resolution and reproducibility of CE separation, different protein extraction methods, organic modifiers in phosphate-glycine buffer and capillary electrophoresis conditions, including capillary length and inner diameter (ID), operating temperature, performance voltages, sample injection times, etc., were investigated. High resolution and reproducibility of WS proteins were achieved using 20% ethanol as the extracting buffer. The optimal condition to separate these proteins was 50 μm ID × 31.5 cm (26.5 cm to the detector) capillary at 11.0 kV and 35°C. The optimum buffer was 0.1 M phosphate-glycine (pH 2.5) containing 20% acetonitrile (ACN) and 0.05% hydroxylpropylmethylcellulose. Using this method, the WS proteins were well separated in less than 10 min. A total of 120 Chinese bread wheat cultivars were analyzed. The CE patterns of most bread wheat cultivars showed a higher level of polymorphisms compared with SDS-PAGE patterns. All cultivars analyzed could be readily differentiated based on their WS protein profiles. Results indicate that the WS proteins are useful biochemical markers for wheat genetics and breeding research and CE is expected to become a new and powerful tool for the separation and characterization of grain WS proteins in bread wheat. Key words: Triticum aestivum, bread wheat, water-soluble proteins, capillary electrophoresis, biochemical markers
Evaluation of genetic diversity and relationshipsin orchardgrass (Dactylis glomerata L.) germplasm based on SRAP markers
Authors: Zeng Bing , Zhang Xin-Quan , Lan Ying , Yang Wu-Yun
Published: April 2011

The present study is the first report of characterizing the levels and patterns ofgenetic diversity in 60 orchardgrass accessions from four continents by sequence-related amplified polymorphism (SRAP) markers. Twenty-one primer pairs were used to produce 480 bands, of which 405 (84.38%) were polymorphic. The genetic similarity coeffic ients (GS) varied from 0.5863 to 0.9686 among the 60 collections, with an average of 0.7891. The genetic diversity of orchardgrass from China and the United States of America were found to be higher than that found in other countries. The dendrogram and principal component analysis realized from these markers clustered the materials into four main groups. The cluster analysis showed that orchardgrass from Australia was different from other collections in genetic diversity. Accessions from the same continent were classified into the same group, indicating that the genetic diversity of orchardgrass and the entire genetic basis of cultivars used in a continent is narrow. Furthermore, cluster analyses suggested that there is correlation between karyotype and morphological characterizations according to the analysis of the five subclusters that clustered from the first group. The information given by SRAP markers was concordant with the morphological variability and karyotype. This showed SRAP marker system could be used efficiently in the study of genetic variability and the evolutionary history of orchardgrasses. Based on the analysis of genetic diversity and relationships, the appropriate strategies for collection and conservation of germplasm resources can be developed and this in turn would help breeding of orchardgrass. Key words: Genetic diversity, genetic relationship, germplasm, orchardgrass, sequence-related amplified polymorphism
Assessment of seed shattering resistance and yield loss in five oilseed crops
Authors: Gan Y. , Malhi S. S. , Brandt S. A. , McDonald C. L.
Published: April 2011

Use of appropriate harvest management can minimize the yield loss of crucifer crops due to seed and pod shattering. This study determined the difference among five canola/mustard species in the degree of resistance to seed shattering and yield losses. Sinapis alba yellow mustard AC Base, Brassica juncea canola Amulet, Brassica juncea mustard Cutlass, Brassica rapa canola Hysyn, and Brassica napus canola InVigor 2663 were grown at Star City, Scott and Swift Current, SK, from 2004 to 2006. Seed yield was highest for napus canola (2146 kg ha-1), followed by juncea mustard (1971 kg ha-1) and juncea and rapa canola, while alba mustard (1547 kg ha-1) was the lowest. Straight combining compared with swathing resulted in 13% greater seed yield for juncea canola and juncea mustard, and 7% greater for rapa canola, while napus canola did not show yield difference between the two operation regimes. Under high shattering conditions, juncea mustard shed about 400 pods m-2, significantly greater than the four other species. Rapa canola had the lowest number of shed pods. Juncea mustard and napus canola had largest yield loss (about 7% of the total seed yield) during straight combining, followed by alba mustard (5%), and rapa and juncea canola (< 4%). Selection of shattering resistant species and use of straight combining can minimize seed yield losses in the production of crucifer oilseed crops. Key words: Brassica napus, Brassica rapa, Brassica juncea, Sinapis alba, swathing, straight–combine
Genetic variation in natural populations of Hordeum brevisubulatum native to the Songnen Prairie in northeastern China: Comparison of four nuclear DNA markers
Authors: Li Mu , Guo Wanli , Hu Lanjuan , Liu Xiaoming , Zhang Yufei , Wu Rui , Gong Lei , Zhang Zhongheng , Liu Bao
Published: April 2011

Hordeum brevisubulatum (Trin) Link, a perennial wild grass, shows high tolerance to salinity- and/or alkaline-eroded soil, and is an important forage grass. Nonetheless, the genetic variation within and among natural populations of this species has not been investigated. In this study, four PCR-based dominant nuclear DNA markers, i.e., amplified fragment length polymorphism (AFLP), inter-simple sequence repeat (ISSR), retrotransposon-microsatellite-amplifiedpolymorphism (REMAP), and random amplified polymor phic DNA (RAPD) were used to investigate the genetic variation of a total of 80 plants with an average of 20 individual plants randomly collected from each of the four natural populations of H. brevisubulatum distributed in the Songnen Prairie in northeastern China. Results indicated that all four markers detected a surprisingly high level of genetic variation among the individual genotypes both within and among populations. Specifically, (i) of the 708 bands produced by 10 AFLP primer pairs, 223 (32%) were polymorphic, corresponding to a genetic similarity coefficient (Dice) range of 0.703 to 0.895 with a mean of 0.793; (ii) of the 174 bands produced by 12 ISSR primers, 149 (85%) were polymorphic, corresponding to a genetic similarity coefficient range of 0.524 to 0.826 with a mean of 0.676; (iii) of the 104 bands produced by REMAP (one retrotransopon-specific primer in combination with each of 8 ISSR primers), 89 (85%) were polymorphic, leading to an average similarity coefficient range of 0.494–0.840 with a mean of 0.688, and; (iv) of the 150 bands produced by 17 RAPD primers, 117 (77%) were polymorphic, giving a similarity coefficient range of 0.526–0.909 with a mean of 0.713. Thus, all four markers are highly informative in detecting genetic variations among the individual genotypes in natural populations of H. brevisubulatum. Nevertheless, no correlation was detected among the markers, suggesting that they likely targeted to different genomic regions of H. brevisubulatum. Whereas ISSR, REMAP and RAPD showed significantly higher levels of polymorphism than AFLP, only the latter was capable of grouping some of the plants largely in accordance with their geographic localities, suggesting population differentiation probably occurred preferentially at genomic regions targeted to by AFLP primers. Key words: Genetic diversity, Hordeum brevisubulatum, Molecular markers, Population differentiation
Mapping of candidate genes associated with late blight resistancein potato and comparison of their location with known quantitative trait loci
Authors: Tian Z. D. , Liu J. , Portal L. , Bonierbale M. , Xie C. H.
Published: April 2011

Phytophthora infestans, the causal agent of late blight, threatens potato production worldwide. Many quantitative trait loci (QTL) for late blight resistance have been mapped in several potato populations. At the same time, numerous expressed sequences tags (EST) related to late blight resistance have been deposited in databases. In order to screen for putative candidate genes associated with late blight resistance, 65 candidate genes were selected for mapping and investigation of their relationship with QTL in three diploid potato populations PCC1, BCT, and PD. In total, 26 primers from the 65 selected genes that showed PCR length polymorphism were mapped on the linkage groups of three populations. Further comparison between map location of QTL and candidate gene loci indicated that three candidate gene markers were placed in a QTL region. The locus of a putative receptor-like protein kinase b co-localized with an important QTL region on chromosome XI of PCC1. In the PD population, the Lox gene was in a QTL with moderate effect on chromosome III and two protein phosphatase loci were localized in a QTL with the largest effect on chromosome XII. These mapped candidate gene markers could be used as a bridge to other genetic maps of potato. The association of candidate genes with QTL forms the basis for further studies on the contributions of these candidate genes to natural variation for potato late blight resistance. Key words: Candidate gene, quantitative resistance loci, late blight, potato
CDC Centennial field pea
Authors: Warkentin Tom , Vandenberg Albert , Tar’an Bunyamin , Barlow Sabine , Ife Scott
Published: April 2011

CDC Centennial, a yellow cotyledon field pea (Pisum sativum L.) cultivar, was released in 2007 by the Crop Development Centre, University of Saskatchewan, for distribution to Select seed growers in Saskatchewan and Alberta through the Variety Release Committee of the Saskatchew an Pulse Growers. CDC Centennial has a semileafless leaf type, fair lodging resistance, powdery mildew resistance, moderately large sized, round seeds, and good yielding ability. CDC Centennial is adapted to the field pea growing regions of western Canada. Key words: Field pea, Pisum sativum L., cultivar description
Island pinto bean
Authors: Mündel H. -H. , Kiehn F. A. , Huang H. C. , Conner R. L. , Balasubramanian P.
Published: April 2011

Island is a high-yielding, tall, partially upright pinto bean (Phaseolus vulgaris L.), with short vines and an average seed weight of 38.5 g 100 seeds-1. It was developed at the Agriculture and Agri-Food Canada (AAFC) Research Centre, Lethbridge, AB, in collaboration with the AAFC Research Station, Morden, MB. Island is well adapted to wide-row irrigated production of the Canadian prairies, with yields exceeding those of Othello, the check cultivar. Island is moderately susceptible, as is Othello, 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: Pinto (bean), cultivar description, high yield
Development and yield potential of grain amaranth in southwestern Québec
Authors: Gélinas G. , Seguin P.
Published: April 2011

The production potential of 29 grain amaranth genotypes was evaluated in southwestern Québec. Considerable variation was observed for all variables studied. In single row plots, grain yield per plant ranged between 13 and 73 g DM (dry matter) plant-1, while in mechanically managed plots grain yield ranged between 432 and 979 kg DM ha-1. All genotypes matured before the first killing frost, but moisture at harvest was high (average of 26%). Grain amaranth production in southwestern Québec seems possible. Key words: Grain amaranth, genotypes, pseudo-cereals, grain yield
Economic and social impacts of organic production systems
Authors: MacRae R. J. , Frick B. , Martin R. C.
Published: April 2011

Given relatively low adoption levels to date, the potential benefits of organic farming systems are not yet very visible. However, there is growing evidence in the literature that adoption of such systems produces multiple environmental, social, and financial benefits that can solve pressing agricultural problems in Canada. Compared with their duration as conventional operations, most organic farms in North America perform better under organic management. This outcome is usually a product of lower input costs, more diversified production and marketing channels, resilience in the face of variable market conditions, higher premiums, and a better capacity to adapt to weather extremes. However, the performance of farming systems including some horticultural and animal production systems, for which our ecological understanding is limited, is still frequently inferior. The data on social impacts are less conclusive, but there is some evidence that when a community has many sustainable (including organic) producers , there are positive shifts in community economic development and social interaction. The reasons appear to be related to the need to hire more labour, the increased demand for local goods and services, and a greater commitment to participation in civic in stitutions. Key words: Organic agriculture, economic performance, social benefits
Metabolic profiling to discriminate wheat near isogenic lines, with quantitative trait loci at chromosome 2DL, varying in resistance to fusarium head blight
Authors: Hamzehzarghani H. , Paranidharan V. , Abu-Nada Y. , Kushalappa A. C. , Mamer O. , Somers D.
Published: April 2011

The resistance in wheat to fusarium head blight (FHB) is controlled by several quantitative trait loci (QTLs), which are mainly expressed as two different types of resistance. The objective of this study was to assess the potential of a metabolomics approach to identify resistance-related metabolites associated with a QTL that confers resistance to FHB. Two near isogenic lines (NIL), with alternate alleles for the FHB resistance/susceptibility QTL on chromosome 2DL, were grown under greenhouse conditions and spikelets were inoculated with F. graminearum. Metabolites were extracted from the rachis and spikelets using a mixture of methanol-water and chloroform, and subsequently analyzed using GC/MS. Compound identification and quantification were achieved using AMDIS, GMD and NIST libraries, and MET-IDEA as the software platform. A total of 182 components were detected. A t-test of the quantities of these metabolites identified 27 resistance-related (RR) metabolites, including 22 constitutive (RRC) and 8 induced (RRI), with three common metabolites. Canonical discriminant analysis was used to classify treatments and to identify the associated metabolic functions. The putative metabolic pathways linking the RR-metabolites identified here are discussed. Key words: Functional genomics, metabolomics, fusarium head blight, Triticum aestivum, Fusarium graminearum
GROWTH CHARACTERISTICS, YIELD COMPONENTS AND RATE OF GRAIN DEVELOPMENT OF TWO HIGH-YIELDING WHEATS, HY320 AND DT367, COMPARED TO TWO STANDARD CULTIVARS, NEEPAWA AND WAKOOMA
Authors: CUTFORTH H. W. , CAMPBELL C. A. , JAME Y. W. , CLARKE J. M. , DePAUW R. M.
Published: April 2011

A high-yielding Canada Prairie Spring (CPS cv. HY320) semi-dwarf wheat and a high-yielding durum line (DT367) were compared to standard hard red spring (cv. Neepawa) and durum (cv. Wakooma) wheats to assess the basis for the yield differences and to examine soil moisture use. The study was carried out under dryland (moisture used from seeding to harvest was 287 mm), partial irrigation (moisture used was 374 mm) and full irrigation (moisture used was 547 mm) on a loam soil at Swift Current during 3 yr. Phenological development was delayed as much as 30 d by improved moisture conditions. At ligule of last leaf visible (LLV), HY320 had one or two more green leaves on the main tiller than did Neepawa; Wakooma generally had one more leaf than DT367. However, leaf area index was generally not different among cultivars. Harvest index was greater for the higher yielding cultivars even though cultivars did not differ in total aboveground dry matter. HY320 generally had the highest grain yield, followed by DT367, Wakooma and Neepawa. Neepawa consistently had the most heads per unit area at harvest but, because of high kernel numbers per head, HY320 produced the greatest number of kernels per unit area; as well, HY320 had large kernels; thus, it had the highest yield potential under optimum growing conditions. HY320 had the highest base temperature (Tb) for kernel growth and the highest kernel growth rates immediately after anthesis; consequently, HY320 kernels completed growth with the lowest accumulated degree days above Tb. DT367 had the highest potential kernel weight and Neepawa the lowest. There were no differences among the cultivars in the amount of moisture used between seeding and harvest.Key words: Wheat (Spring), yield components, grain development, moisture use, growing degree days, harvest index
THE EFFECT OF WATER DEFICIT ON N2(C2H2) FIXATION BY WHITE BEAN AND SOYBEAN
Authors: SMITH D. L. , DIJAK M. , HUME D. J.
Published: April 2011

White bean (Phaseolus vulgaris L.) is generally reported to fix less N than soybean (Glycine max Merrill [L.]). Recent work has shown that in soybean the onset of physiological responses that conserve plant and soil water occurs at greater water deficits than in some other legumes. Little is known about water use regulation in white bean. Research was conducted to compare the responses of these two species to water deficit, particularly its effects on N2 fixation, in both controlled environment and field conditions. In the growth room, plant water potential, leaf diffusive resistance, acetylene reduction and nodule mass per plant were measured for both species during progressive drought, and compared to watered controls. In the field, the leaf diffusive resistance of irrigated and unirrigated plants of both species was measured, as was the soil water potential in plots where these crops were grown. Under conditions of increasing water deficit white bean reacts to conserve plant and soil water sooner than soybean: closing its stomates earlier under drought conditions and maintaining higher plant water potentials. White bean acetylene reduction declined more rapidly over time and over plant water potential levels, but not over changes in leaf diffusive resistance, than that of soybean, as the droughting progressed. In the field, under drought conditions, white bean root nodules senesced, while soybean nodules did not, and white bean was observed to exhibit more parahelionasty than soybean. The onset of physiological responses that conserve plant and soil water occurred at lesser water deficits in white bean than soybean, and this was reflected in more extreme effects on N2 fixation by white bean.Key words: White bean, soybean, water deficit, acetylene reduction, nitrogen fixation, nodulation
CONTROL OF QUACKGRASS WITH GLYPHOSATE AND ADDITIVES
Authors: IVANY J. A.
Published: April 2011

Addition of nonionic surfactants nonylphenoxyl polyethoxy ethanol at 0.1% of total spray volume (vol/vol), tallow amine ethoxylate at 0.5% (vol/vol), or oil concentrate at 1% (vol/vol) to commercially formulated glyphosate applied at 0.25 and 0.5 kg a.i. ha−1 improved control of quackgrass [(Agropyron repens (L.) Beauv.)]. However, the improvement was not sufficient to provide an acceptable level of control of quackgrass. Addition of ammonium sulphate to glyphosate gave significantly greater control of quackgrass at all three rates of glyphosate. In one of the two experiments, control with 0.5 kg a.i. ha−1 of glyphosate was comparable to that of 1.0 kg a.i. ha−1. Addition of either of the three surfactants to the ammonium sulphate and glyphosate combinations did not further enhance control.Key words: Ammonium sulphate, nonylphenoxy polyethoxy ethanol, tallow amine ethoxylate, oil concentrate, Agropyron repens (L.) Beauv.
RESPONSE OF SUNFLOWER HYBRIDS TO ROW SPACING
Authors: GUBBELS G. H. , DEDIO W.
Published: April 2011

An early- and a late-maturing oilseed sunflower (Helianthus annuus L.) hybrid were grown at 45- and 90-cm row spacings in the 1984 to 1986 seasons at Morden, Manitoba. In the 45-cm rows compared to the 90-cm rows, plant height was reduced approximately 9 cm, and achene yield was increased 14.5% for the early hybrid. Response of the late hybrid to row spacing was minimal.Key words: Oilseed sunflower, Helianthus annuus L., row spacing
CENTRALIA FIELD BEAN
Authors: PARK S. J. , TU J. C. , AYLESWORTH J. W. , BUZZELL R. I.
Published: April 2011

Centralia is a medium-early short vine white (navy or pea) bean (Phaseolus vulgaris L.) cultivar that matured 2 d later than OAC Seaforth and 3 d earlier than Harokent in Ontario field bean cultivar trials. Its main advantage is its high seed yield as an early-maturing cultivar outyielding Midland by about 11%. Its cooking quality is acceptable and similar to that of recommended white bean cultivars in Ontario. Centralia is resistant to all domestic races of bean anthracnose (Colletotrichum lindemuthianum) and to races 1 and 15 of bean common mosaic virus.Key words: Cultivar description, white (navy, pea, common or dry edible) bean, bean anthracnose, bean common mosaic virus
Mechanisms of resistance to the flea beetle, Phyllotreta cruciferae (Goeze), in mustard seedlings, Sinapis alba L.
Authors: Bodnaryk R. P. , Lamb R. J.
Published: April 2011

Antixenosis (nonpreference) and tolerance were identified as two mechanisms of resistance in seedlings of mustard, Sinapis alba 'Ochre', that likely account for the high level of resistance that this plant shows to flea beetles, Phyllotreta cruciferae Goeze, in the field. Sinapis alba showed antixenosis in no-choice and choice feeding tests with a susceptible species, Brassica napus 'Westar'. The beetles consumed about twice as much of the B. napus foliage as compared with S. alba. The highest level of antixenosis occurred in younger seedlings, indicating that S. alba puts forth an optimum defense when it is most vulnerable to flea beetle herbivory. Seedlings of S. alba were tolerant of low levels of flea beetle feeding damage to their cotyledons and continued to grow at almost the same rate as undamaged seedlings, whereas the growth of B. napus declined continuously with the level of feeding damage. The level of tolerance shown by S. alba combined with antixenosis probably accounts for the resistance reported for this crop in the field. In comparison with S. alba, B. napus seedlings, which show no tolerance and are preferred hosts, succumb rapidly to flea beetle attack unless protected with an insecticide. Key words: Insect resistance, mechanism, flea beetle, seedling, mustard, Sinapis alba
Photoperiod response characteristics of alfalfa (Medicago sativa L.) cultivars
Authors: Major D. J. , Hanna M. R. , Beasley B. W.
Published: April 2011

Ten cultivars of alfalfa (Medicago sativa L.) were exposed to low temperatures for varying times and to a series of photoperiods in controlled environment cabinets to determine vernalization and photoperiod responses. There was a reduction in time of 2–16 d from emergence to flowering for vernalization treatments. Vernalization treatments of less than 1 d or greater than 28 d had similar numbers of days from emergence to flowering. The photoperiod response characteristics included the basic vegetative phase (BVP), which is a juvenile phase that must be completed before the plant is responsive to photoperiod, the maximal optimal photoperiod (MOP), the photoperiod beyond which flowering occurs in a constant number of days, and photoperiod sensitivity, the number of days delay in flowering per hour increase in photoperiod. Anik and Vernal comprised a group with the longest BVP, 29.0 d; a group of six cultivars had a mean BVP of 27.6 d, and Maris Kabul and Saranac had the shortest BVP, 25.6 d. The MOP was greatest for Beaver (19 h), shortest for Vernal (17.7 h) and intermediate for the remaining cultivars (18.3 h). Alfalfa was confirmed as a long-day plant, because the time to flowering decreased as photoperiod was lengthened. This results in negative photoperiod sensitivity values. Anik, with a photoperiod sensitivity of −20.50 d h−1, was different from the rest of the cultivars, with a photoperiod sensitivity ranging from −8.51 to −5.08 d h−1. These results demonstrate that alfalfa photoperiod response is consistent with the general response observed for annual long-day species of crop plants and suggest that legume breeders may be able to incorporate specific photoperiod characteristics into alfalfa cultivars in order to optimize harvest dates. Key words: Daylength, development, flowering
Bura spring triticale
Authors: Nass H. G. , Johnston H. W. , Zillinsky F. J. , Kohli Man Mohan , Blatt C. R. , Bubar J. S. , Walton R. B. , Rodd A. V.
Published: April 2011

Bura is a spring triticale (X Triticosecale Wittmack) with high yield, high test weight, high kernel weight, resistance to powdery mildew, and adapted to Eastern Canada. Key words: Triticale (spring), X Triticosecale Wittmack, cultivar description
Herbicidal properties of alpha-terthienyl, a naturally occurring phototoxin
Authors: Lambert J. D. H. , Campbell Glenn , Arnason J. T. , Majak W.
Published: April 2011

The herbicidal efficacy of alpha-terthienyl (α-T), a naturally occurring phototoxin, was investigated in pot and field trials. The phototoxin acted as a contact herbicide on corn and broad leaf weeds and produced necrotic lesions under solar or solar-simulating illumination. In comparison to currently used herbicides such as atrazine, the efficacy of α-T for growth inhibition of the weed species was low with 50% inhibition of growth at 15 to 29 kg ha−1. Key words: Alpha-terthienyl, phototoxin, herbicide, corn, weeds
Optimizing aerial environments for greenhouse rose production utilizing whole-plant net CO2 exchange data
Authors: Jiao J. , Tsujita M. J. , Grodzinski B.
Published: April 2011

A daily growth model was developed for Samantha roses based on nondestructive measurements of whole-plant net CO2 exchange rate (NCER) under various aerial environmental conditions. Irradiance, CO2 concentration, and temperature accounted for 70, 20, and 5%, respectively, of the variance in whole-plant net photosynthesis explainable by a second-order polynomial model (R2 = 0.86). The predicted optimal temperatures for whole-plant net photosynthesis increased from 19 to 24 °C with increasing irradiance from 100 to 1200 μmol m−2 s−1 and CO2 concentration from 350 to 1500 μL L−1. Dark respiration rate increased exponentially with temperature and could be predicted by the Arrhenius equation. Even though respiratory carbon (C) loss at night increased linearly with daytime C gain, daily C gain (AC) was still proportional to daytime net photosynthesis. The relative contribution of irradiance (100–1200 μmol m−2s−1), day length (8–16 h), CO2 concentration (350–1500 μL L−1), day temperature (15–30 °C), and night temperature (15–25 °C) to plant daily growth was 64, 31, 4, 0.3, and 0.7%, respectively. Key words: Carbon balance, environment, modelling, photosynthesis, respiration, Rosa hybrida
Response of alfalfa to bidirectional selection for root bark area and xylem vessel diameter
Authors: Wang Shaoke , Brick M. A. , Townsend C. E.
Published: April 2011

Development of alfalfa [Medicago sativa L. ssp. sativa and M. sativa ssp. falcata (L.) Arcangeli] germplasm with contrasting root bark area and xylem vessel area could be useful to evaluate relationships between anatomical root characteristics and plant functions such as drought tolerance. This study was conducted to determine the response of alfalfa to bidirectional selection for root bark area and xylem vessel area of the largest vessels as viewed in cross section. Bidirectional selection for large and small root bark area and for large and small xylem vessel area was conducted for two cycles. Selection for high root bark area resulted in an increase in root bark area in cycle one (C1), but no further response occurred in cycle two (C2). Response to selection for low bark area resulted in no response in the C1, but a response occurred in the C2. Response to selection for large xylem vessel area increased xylem area in the C1 but no further response occurred in the C2. There was no response to selection for small vessel area in either of the two cycles of selection. Asymmetrical responses to bidirectional selection were found. Root size increased significantly over the two cycles of selection and was probably due to indirect selection for large root size. Key words: Medicago sativa L., ssp. sativa and M. sativa ssp. falcata (L.) Arcangeli, root bark area, xylem vessel diameter
Hard-seed content of alfalfa grown in Canada
Authors: Fairey D. T. , Lefkovitch L. P.
Published: April 2011

The hard-seed content of alfalfa (Medicago spp.) grown in Canada in relation to genotype and geographic location of production was surveyed for the commercial growing regions in Manitoba, Saskatchewan, Alberta and British Columbia. The average hard-seed content of all pedigreed production over a 5-yr period, ranged from 22 to 37% and that in nonpedigreed production was between 14 and 30%. A database of the five widely grown cultivars revealed that the hard-seed content of alfalfa in the most northerly growing areas in the Peace River region of Alberta and British Columbia ranged from 31 to 51%, while hard seed content of alfalfa produced elsewhere varied from 22 to 38%. There was no apparent effect of latitude on the proportion of hard seeds, while there was a small increase for two of the five cultivars in production areas further west. Of particular interest was the trend in viable seed production. There was consistent evidence suggesting that the proportion of viable seeds decreased in production areas further north, but increased in production areas further west. However, the minimum viability was always in excess of 85%. There was no correlation between hard and viable seed. Key words: Medicago spp., alfalfa, lucerne, hard seeds, viable seeds
Analysis of biological traits contributing to grain yield of short-to mid-season corn (Zea mays L.) hybrids
Authors: Dwyer L. M. , Hayhoe H. N. , Royds W. , Hamilton R. I.
Published: April 2011

Biological traits related to grain yield of short- to mid-season corn (Zea mays L.) hybrids were identified, and an approach to determine their relative contribution to grain yield was demonstrated. Nine hybrids with maturity ratings of 2350–2800 corn heat units (CHU) were grown at three sites. Twelve plant-scale traits were measured which reflected development rate, vegetative growth and partitioning to the grain. Analyses indicated significant differences (P ≤ 0.05) in grain yield among hybrids, maturity ratings and sites. Hybrid yield differences were related to hybrid differences in trait values. Traits contributing to yield differences were also selected by a series of multiple linear regressions. The test year was abnormally warm (all sites had more than 2800 CHU) and traits related to the vegetative stature of the plant and the time required to reach that stature were most consistently correlated with yield. Key words: Plant traits, maize, regression, grain yield, breeding
A comparison of the freezing tolerance of downy brome, Japanese brome and Norstar winter wheat
Authors: O'Connor B. J. , Gusta L. V. , Paquette S. P.
Published: April 2011

The freezing tolerance of downy (Bromus tectorum L.) and Japanese (Bromus japonicus) brome were compared to Norstar winter wheat (Triticum aestivum L.) collected from similar sites. From December to April of 1987 downy brome was either equal to or superior in freezing tolerance to the winter wheat. Of the three species, Japanese brome was slightly less hardy in December but was of equal freezing tolerance in March and April. There was no correlation between freezing tolerance and tissue water content or tissue dry weight in the three species. These two bromes may become a serious weed in winter wheat because their cold hardiness is either equal or superior to our hardiest winter wheat cultivars. Key words: Downy brome, Japanese brome, winter wheat, freezing tolerance
Delfield flue-cured tobacco
Authors: Pandeya R. S. , Brandle J. E. , Ankersmit J. C. D. , Rogers V. D. , Keller W. A.
Published: April 2011

Delfield, a flue-cured tobacco (Nicotiana tabacum L). cultivar, has higher yield than Delhi 76, but similar grade price and therefore provides higher returns to growers. Delfield originated from a somatic hybrid between N. tabacum and N. rustica. Key words: Nicotiana tabacum L., tobacco, somatic hybridization, cultivar description
Culm height and susceptibility of Canadian winter and spring wheat cultivars to common bunt (Tilletia tritici and T. laevis)
Authors: Gaudet D. A. , Puchalski B. J. , Entz T.
Published: April 2011

A field study involving winter and spring wheat cultivars possessing race-specific and nonspecific resistance to Tilletia tritici and T. laevis was conducted to determine the effect of bunt on culm dwarfing, and the role of culm height in the susceptibility of wheat cultivars. Bunt-induced stunting, ranging from 2.4 to 21%, was observed in 20 of 25 cultivars and the severity was correlated with level of bunt (r = 0.86). Also, there was preferential infection of shorter culms by the bunt fungus and this appeared to be a major factor in the susceptibility of most cultivars in this study. Cultivars possessing moderate to high levels of nonspecific resistance such as Katepwa and Chinook had fewer short culms; these short culms were susceptible. A large proportion of the culms of short-statured or semi-dwarf cultivars such as HY320, Tobari 66, and the soft white spring wheats Fielder and Springfield, fell into the shortest height classes; uniformly these were highly susceptible to bunt infection. Laura and Roblin, cultivars of conventional height, had a large proportion of short culms and these were highly susceptible. Red Bobs 222 and HY355 also exhibited high levels of bunt in the taller culms. Cultivars possessing race-specific resistance such as the durum wheats and BW553 had low levels of infection across the culm height classes. Cultivar variation in susceptibility to bunt within each of the different culm height classes also was observed. The possible implications of the effect of preferential bunting of short culms on development in short-statured or semi-dwarf wheats are discussed. Key words: Stinking smut, Norin 10/Brevor
Sources and inheritance of resistance to Russian wheat aphid in Triticum species amphiploids and Triticum tauschii
Authors: Nkongolo K. K. , Quick J. S. , Limin A. E. , Fowler D. B.
Published: April 2011

The Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), has caused significant losses to wheat and barley in Canada, Mexico, and the USA during 1986–1990. Sources of resistance to the RWA have been found in wheat and related species. This study was conducted to determine the inheritance of resistance to the RWA in an amphiploid derived from crosses between Triticum tauschii and T. turgidum and to identify new sources of RWA resistance in T. tauschii. Many Triticum tauschii lines and amphiploids derived from crosses between T. tauschii and T. turgidum, T. tauschii and T. timopheevii, and T. ventricosum and T. turgidum have been screened for resistance to the Russian wheat aphid in greenhouse tests. The results of this study confirmed that resistance of these amphiploids is derived from T. tauschii, T. timopheevii, and T. ventricosum. New sources of RWA resistance were identified in T. tauschii species, the donor of the D genome in common wheat. A resistant amphiploid (synthetic hexaploid wheat) derived from a cross between T. tauschii and T. turgidum, was crossed with two susceptible common wheats (T. aestivum L.) 'Yorkstar' and 'Norstar' to study the inheritance of RWA resistance derived from T. tauschii. F1 and F2 reactions indicated that resistance to the RWA in this amphiploid is simple and recessive. The gene symbol Dn3 is proposed for resistance in T. tauschii SQ24. Key words: Russian wheat aphid, Diuraphis noxia, Triticum tauschii, amphiploid, resistance gene, inheritance
Effects of nitrogen fertilizer, cutting frequency, and companion legume on herbage production and quality of four grasses
Authors: Fairey N. A.
Published: April 2011

Carlton smooth bromegrass (Bromus inermis Leyss.), Regar meadow bromegrass (B. biebersteinii Roem et Schult.), Climax timothy (Phleum pratense L.), and Oregon commercial meadow foxtail (Alopercurus pratensis L.) were each grown alone or in binary mixture with Peace alfalfa (Medicago sativa L.), Dawn alsike clover (Trifolium hybridum L.), or Cree birdsfoot trefoil (Lotus corniculatus L.) for three production years under three management systems: two cuts with no nitrogen (N) fertilizer; two cuts with 150 kg ha−1 N fertilizer; and four cuts with 150 kg ha−1 N fertilizer. With two cuts per year and no N fertilizer, herbage productivity of each grass was greater when the grass was grown in association with alfalfa than when grown alone, with alsike clover, or with trefoil. With N fertilization, herbage productivity was reduced by cutting more than twice per year, the magnitude of the reduction being smooth bromegrass > meadow bromegrass > timothy > meadow foxtail; yields of smooth bromegrass were almost halved whereas those of meadow foxtail were virtually unaffected, and this effect was consistent for each companion legume treatment. Under conditions of non-limiting soil-N, herbage productivity and N concentration were controlled more by the adaptation of each grass, and its response to frequency of cutting, than by species composition of the seeding mixture. Without supplemental N fertilizer, alfalfa was the most suitable companion legume to enhance the agronomic performance of each of the four grasses. Key words: Forage, nitrogen, cutting frequency, simulated grazing, grass-legume mixtures
Genetic variation in alfalfa for ruminal protein degradability
Authors: Broderick G. A. , Buxton D. R.
Published: April 2011

Protein in alfalfa is extensively degraded in the rumen and is often wasted due to excessive ammonia formation. The objective of this study was to determine if there are genetic differences in ruminal degradability of alfalfa forage protein. Two replicates of field-grown forage were taken at each of two different cuttings from 22 alfalfa entries (Medicago spp.), including 19 of M. sativa plus three of M. falcata (total 88 samples). The forage was analyzed for acid detergent fiber (ADF), total N and acid detergent insoluble N (ADIN), and for degraded N at 0-h, potentially degradable protein, rate of protein degradation, and net protein escape (total escape minus ADIN) using a ruminal inhibitor in vitro system. There were no differences in ADF, total N or ADIN among the 22 alfalfa entries. Significant differences among entries were detected for the four parameters determined using the in vitro system: N degraded at 0-h (P < 0.002), degradable protein (P < 0.0025), degradation rate (P < 0.001), and net protein escape (P < 0.001). There were trends for the 19 entries of M. sativa to have larger degraded N fractions and smaller degradable protein fractions than the three entries of M. falcata. The 19 entries of M. sativa germplasm had degradation rates ranging from 0.21 to 0.25 h−1, whereas those for M. falcata averaged 0.18 h−1. Estimated net protein escapes from the rumen averaged 171 and 212 g kg−1 total nitrogen for M. sativa and M. falcata, respectively (24% greater for M. falcata). Estimated net protein escapes for the three M. falcata entries were greater than 18 of 19 M. sativa entries. The consistency of these differences suggests that conventional plant breeding techniques could be used to develop lines of alfalfa forage with improved protein utilization in ruminants. Key words: Alfalfa, Medicago sativa L., Medicago falcata L., ruminal protein escape
The biology of Canadian weeds. 98 Potentilla anserina L.
Authors: Miyanishi K. , Eriksson O. , Wein R. W.
Published: April 2011

Potentilla anserina L., silverweed (Rosaceae), occurs in all provinces of Canada as well as in the two territories. Although generally found in wet sandy areas along rivers and on beaches, silverweed also occurs in waste areas, along roadsides, and in lawns. This shade-intolerant stoloniferous plant has recently become dominant in overgrazed sedge meadows of the Peace-Athabasca Delta, resulting in deterioration of portions of the primary range for wood bison in Wood Buffalo National Park in northern Alberta. This contribution presents both a review of the literature and some original data on the biology and ecology of the species. Key words: Silverweed, disturbance, ecology, herbaceous perennial, demography
Response of quackgrass biotypes to glyphosate and quizalofop
Authors: Tardif François J. , Leroux Gilles D.
Published: April 2011

The response to glyphosate and quizalofop of five quackgrass (Elytrigia repens (L.) Nevski) biotypes treated at the three- to four-leaf and six- to seven-leaf stage was tested. Shoot and rhizome-bud control 1 yr after treatment did not differ among biotypes treated at the three-to four-leaf stage regardless of the herbicides and rates. At the six- to seven-leaf stage, difference in shoot control between the most tolerant and the most sensitive biotypes was 54 and 40% after treatment with quizalofop at 100 and 150 g a.i. ha−1, respectively. Shoot control at the six- to seven-leaf stage ranged between 59 and 97%, with glyphosate at 450 g a.i. ha−1. When averaged over all treatments and stages of growth, control of shoot number was positively correlated with control of rhizome bud number. A negative correlation existed between the percent shoot control at the six- to seven-leaf stage and the number of tillers, rhizomes, and rhizome buds, and with the total biomass of the biotypes at time of treatment with quizalofop at 100 g ha−1. Leaf retention on the lower leaves of plants at the three- to four-leaf stage varied among biotypes, but was not related to treatment tolerance. Key words: Glyphosate, quizalofop, rhizome buds, shoot control, Elytrigia repens
The effect of ammoniation on the nutritive value of tall wheatgrass
Authors: Cohen R. D. H. , Cruise K. A. , Kernan J. A. , Coxworth E. C. , Knipfel J. E.
Published: April 2011

Tall wheatgrass (TWG, Agropyron elongatum (Host) Beauvois) was harvested at anthesis, ammoniated, fed to sheep and its nutritive value was compared with that of nonammoniated TWG. Ammoniation increased organic matter digestibility (OMD) from 59.2 to 65.9% (SEM = 1.45; P < 0.001), acid detergent fibre digestibility (ADFD) from 53.2 to 63.4% (SEM = 2.14; P < 0.001), neutral detergent fibre digestibility (NDFD) from 55.2 to 69.3% (SEM = 2.90; P < 0.001), digestible organic matter (DOMI) from 25.8 to 44.3 g kg−0.75 d−1 (SEM = 3.90; P < 0.001) and digestible crude protein intake (DCPI) from 1.33 to 5.97 g kg−0.75 d−1 (SEM = 0.97; P < 0.001). Key words: Tall wheatgrass, ammoniation, intake, digestibility, fibre, sheep
An efficient method to evaluate alfalfa cultivars for resistance to verticillium wilt
Authors: Huang H. C. , Hanna M. R.
Published: April 2011

A growth-room technique was developed to evaluate alfalfa cultivars for resistance to verticillium wilt caused by Verticillium alba-atrum Reinke & Berthold. The process involves growing alfalfa seedlings in Cornell mix in Roottrainers™ and inoculating the seedlings in batches of 96, without digging, root-washing or transplanting individual seedlings. This method was shown to be effective and efficient in screening large numbers of alfalfa seedlings, approximately 1000 seedlings m−2, using little growth-room space and minimum labor. Key words: Verticillium albo-atrum, Medicago sativa, resistance, technique, alfalfa
Interaction of the rate of P and K fertilization on the yield response of three forage legume species
Authors: Zebarth B. J. , Sheard R. W.
Published: April 2011

A response surface model was used to study the interaction between the rate of P and K fertilization on yield of three legume forage crops: alfalfa (Medicago sativa L.), trefoil (Lotus corniculatus L.), and red clover (Trifolium pratense L.). The results suggest that the soil test calibration recommendations developed for P or K on forage legumes are relatively insensitive to the rate of the other nutrient applied. Key words: Alfalfa, red clover, trefoil, soil test calibration, response surface model
Screening winter wheat for resistance to cottony snow mold under controlled conditions
Authors: Gaudet D. A. , Kozub G. C.
Published: April 2011

A screening test was developed to determine the level of resistance of winter wheat to cottony snow mold (Coprinus psychromorbidus) under controlled conditions. The best separation in disease reaction among cultivars occurred following prehardening growth for 1 wk at 20 °C, hardening at 2 °C for 3 wk, and inoculation and incubation with the cottony snow mold pathogen at −3 °C for 9 wk. Percent survival was determined following a 3-wk recovery in the greenhouse. Extending prehardening growth to 6 wk increased the overall level of survival, but reduced the ability of the screening test to differentiate among cultivars. In general, there was a decrease in the percent survival in the 3-wk prehardening growth treatment compared with the 1- and 6-wk treatments. Percent survival and the ability to differentiate among cultivars decreased with increasing length of incubation with the cottony snow mold pathogen at −3 °C. The snow mold resistance and LT50 temperatures of 24 winter wheat cultivars, Kodiak fall rye and winter triticale were determined. Winter wheat cultivars CI14106, PI186822, Sprague, M81-8661, Münstertaler, and PI172582 exhibited high percentage survival following inoculation with cottony snow mold, but all cultivars exhibited low levels of freezing resistance except Münstertaler, which exhibited an intermediate level of freezing resistance. Key words: Freezing resistance, winter wheat
Performance of alfalfa strains grown in mixture with smooth bromegrass as affected by management
Authors: Bittman S. , Waddington J. , McCartney D. H.
Published: April 2011

This study was conducted to evaluate the yield and persistence of seven contrasting alfalfa (Medicago sativa L. sensu lato) strains growing in binary mixture with smooth bromegrass (Bromus inermis Leyss.) under different fertilizer and cutting managements. The alfalfa strains were seeded in mixtures with smooth bromegrass in 1980 in northeast Saskatchewan and harvested each year, 1982 through 1987. Two fertilizer treatments (0 and 18 kg ha−1 P) and two cutting managements (2 and 3-4 cuts) were imposed annually. The application of P fertilizer increased the total yield (6-yr average) from 1.47 t ha−1 in control plots to 2.52 t ha−1 in the fertilized plots. Frequent cutting reduced average total yield from 2.59 t ha−1 (2-cut system) to 1.4 t ha−1. Fertility and cutting management did not affect the proportion of alfalfa or weeds in the harvested herbage. The alfalfa strain significantly affected total yield and the proportion of alfalfa and weeds throughout the years of this study. The strain ScMf3713, a M. sativa subsp. falcata (L.) Arcang. type, outyielded all entries during the last 3 yr of this study. The study suggests that alfalfa strains of the falcata subspecies germplasm showed superior long-term performance when the alfalfa was grown in a binary mixture with bromegrass. Key words: Medicago sativa L., falcata, Bromus inermis Leyss., phosphorus, simulated grazing