bluuebunny/crossref_metadata_2025 huggingface dataset:
Cultivar and storage effects on germination and hard seed content of alfalfa
Authors: Acharya S. N. , Stout D. G. , Brooke B. , Thompson D.
Published: April 2011

The impermeable coat of alfalfa (Medicago sativa L.) seed can reduce germination to an extent unacceptable for commercial use. The usual method of increasing germination of lots with high proportion of impermeable or hard seeds, mechanical scarification, can damage seeds. Experiments were conducted to determine the effect of cultivar, year of production and storage conditions on germination and hard seed content in alfalfa. Experiments with four Canadian cultivars indicated a significant effect of cultivar on seed weight, germination and hard seed content in freshly harvested seed. Year of production had a greater influence on these seed traits than cultivar. Under uncontrolled storage conditions, germination of 35 alfalfa synthetics increased and hard seed content decreased with time, although not at the same rate for all synthetics. Storage at 20 °C for up to 64 mo did not significantly decrease hard seed content. At 35 °C, hard seed content decreased continuously for all cultivars (for one cultivar to <5%) after 64 mo. Over 80.5 mo storage at room temperature (22 ± 2 °C), germination increased in a nonlinear fashion. Storing seed in sealed plastic bags at 35 °C delayed seed dehydration and the loss of hard seeds. Levels of nonviable seed were low (<10%), even after storage at 35 °C for 64 mo. Brief (1 min) exposure to liquid nitrogen increased germination of freshly harvested alfalfa seed to >90%. The results indicate that the germination percent of alfalfa can be increased and hard seed content reduced by short exposure to liquid nitrogen or storage at nonlethal high temperatures (35 °C) such that mechanical scarification may be unnecessary. Key words: Medicago sativa, hard seed, stored seed, seed dehydration, high temperature treatment, liquid nitrogen treatment
Effect of swathing on alternaria black spot in Brassica rapa canola in Saskatchewan
Authors: Duczek L. J. , Seidle E. , Reed S. L. , Sutherland K. A. , Rude S. V. , Rimmer S. R.
Published: April 2011

From 1990 to 1997, experiments were conducted comparing the effect of swathing versus straight combining on seed infection by Alternaria species and on quality of harvested seed. This was done at several locations in Saskatchewan using a number of cultivars of Brassica rapa and B. napus. The level of A. brassicae in harvested seed was significantly higher in straight-combined than in swathed treatments. Green seed count and seed weight were not affected by treatment. Seed germination was reduced, but not always significantly, with straight combining compared to swathing. This data support the recommendation for swathing at the optimal time to reduce alternaria black spot when the potential for disease development is high. Swathing reduces the time for disease development because it reduces the time of ripening compared with straight combining. Key words: Alternaria black spot, Alternaria brassicae, canola, swathing
PRO 280 Soybean
Authors: Ablett G. R. , Stirling B. T. , Fischer J. D.
Published: April 2011

PRO 280 is an early Maturity Group I soybean (Glycine max [L.] Merr.) cultivar with good yield potential and lodging resistance. Key words: Soybean, cultivar description
Floret sterility and outcrossing in two spring wheat cultivars
Authors: Briggs Keith G. , Kiplagat Oliver K. , Johnson-Flanagan Anne M.
Published: April 2011

A tendency for higher outcrossing potential in Canadian semidwarf wheat (Triticum aestivum L.) cultivars compared with tall Canadian cultivars has been postulated by breeders and seed growers. In the present study, the outcrossing potential of a semidwarf Canada Prairie Spring wheat (Triticum aestivum L.) cv. Cutler and a conventional height Canada Western Red Spring wheat, cv. Roblin was determined under controlled greenhouse conditions. Outcrossing of each cultivar was induced by applying moisture stress followed by exposure to pollen from a phenotypic marker stock, cv. P8901. In the controlled absence of external pollen, moisture stress significantly reduced seed set in both cultivars. Application of external pollen following moisture stress increased seed set significantly in Cutler and nonsignificantly in Roblin, and was associated with a higher level of floret opening in Cutler. Outcrossing frequency was also assessed by analysing progeny seed (selfed or outcrossed) using acidic polyacrylamide gel electrophoresis of seed protein, RAPD markers and morphological phenotype, including height, awnedness, black chaff and time to maturity. All three assay techniques demonstrated a higher outcrossing frequency in Cutler than in Roblin under this protocol. The frequency of outcrossing in different parts of the spike was also determined for both cultivars. In both cultivars the highest proportion of outcrossing was found in the mid-upper region of the spike, followed by the mid-lower region. Key words: Floret sterility, moisture stress, outcrossing, Triticum aestivum
Westag 97 Soybean
Authors: Ablett G. R. , Stirling B. T. , Fischer J. D.
Published: April 2011

Westag 97 is a highly productive Maturity Group I soybean (Glycine max [L.] Merr.) cultivar with good tolerance to phytophthora root rot. Key words: Oilseed, cultivar description, soybean
Control of wild oat in the year of smooth bromegrass establishment and its effect on the yield and quality of subsequent seed crops
Authors: Darwent A. L. , Moyer J. R.
Published: April 2011

Wild oat (Avena fatua L.) control from three graminicides, clodinafop-propargyl, fenoxaprop-p-ethyl and tralkoxydim, in seedling stands of smooth bromegrass (Bromus inermis L.) seeded alone or with spring wheat (Triticum aestivum L.) was studied in 1991, 1992 and 1993 at Beaverlodge, Alberta. Seed yield and quality were measured for 2 yr after each year of establishment. In the year of establishment, clodinafop-propargyl at 60 g ha–1 consistently provided ≥80% visual control of wild oat growing in smooth bromegrass seeded with wheat, while the mean probability of similar applications of fenoxaprop-p-ethyl at 92 g ha−1 and tralkoxydim at 250 g ha−1 to provide ≥80% visual control of wild oat, averaged over the years of establishment, was 0.91 and 0.92, respectively. Without the wheat companion crop, the mean probability of clodinafop-propargyl to provide ≥80% visual control of wild oat, averaged over establishment years, remained above 0.90, but that for fenoxaprop-p-ethyl and tralkoxydim was reduced to 0.36 and 0.50, respectively. The efficacy of the three graminicides to control wild oat was reduced by tank mixing with bromoxynil plus MCPA, thifensulfuron methyl plus MCPA, or MCPA alone. Establishment with wheat had a major detrimental impact on smooth bromegrass seed yields harvested 1 and 2 yr after each establishment year. Smooth bromegrass seed yields harvested 1 yr following the year of establishment were three times greater where smooth bromegrass was seeded alone as compared with being seeded with wheat. Seed yields harvested 2 yr after the year of establishment followed a similar trend, but the differences were smaller. Herbicide treatments had no effect on either first or second smooth bromegrass seed yields. Wild oat dockage was present only in the first smooth bromegrass seed crop and was approximately three times greater following establishment with wheat than following establishment alone. Percent wild oat dockage was less from plots where herbicides had been applied than from weedy check plots. Differences in percent dockage occurred among herbicide treatments but were small. Key words: Smooth bromegrass, Bromus inermis, wild oat, Avena fatua, graminicides, tank mixtures
Chinook apple
Authors: Quamme H. A. , MacDonald R. A. , Lane W. D. , Hampson C. R.
Published: April 2011

Chinook is an attractive, high-quality apple cultivar ripening after Red Delicious. It was selected for its outstanding appearance, texture and flavour and long storage life. Key words: Malus domestica Borkh., dessert apple, cultivar description
A forced-air self-cleaning system for a Wiley-type mill
Authors: Drapeau R.
Published: April 2011

A forced-air self-cleaning system was designed and installed on a Wiley-type laboratory mill. This system reduces the time required to grind a forage sample by 30%. In addition, this forced-air self-cleaning system allows the operator to remove the facial mask by reducing dust and improving air quality and diminishing health risks. Key words: Mill, self-cleaning system
Multivariate classification of farming systems for use in integrated pest management studies
Authors: Leeson J. Y. , Sheard J. W. , Thomas A. G.
Published: April 2011

On-farm studies provide a realistic setting to examine the impact of interactions of management practices on weed communities within various farming systems. Clustering farm units into groups that use similar management practices enables the replication of farm management systems within on-farm studies. The goal of this study is to objectively classify farm units into management systems on the basis of quantitative variables describing aspects of cropping history and chemical input levels using multivariate techniques. Twenty-eight Saskatchewan farmers provided details of their management practices from 1990 to 1997 through a series of questionnaires. Twelve variables derived from the questionnaires were used to describe cropping history, pesticide, tillage and fertilizer use on each farm unit. These variables were used to cluster farm units using minimum variance classification and NMS ordination. Both techniques identified seven farm management systems. The greatest differences were observed between organic and non-organic systems. Farm management systems that used annual fallow and continuous annual cropping histories were most similar. The consistent results obtained by use of the two unrelated methodologies indicate the utility of this approach for the classification of farm management systems. Key words: Farm management system, classification, cropping history, chemical input level, on-farm
Inheritance of self-compatibility and flower morphology in an inter-specific buckwheat hybrid
Authors: Woo Sun Hee , Adachi Taiji , Jong Seung Keun , Campbell Clayton G.
Published: April 2011

This study was conducted to determine the inheritance of self-compatibility and homomorphic flower type when the wild species Fagopyrum homotropicum was crossed with common buckwheat (F. esculentum). Unidirectional interspecific hybrids between cultivated F. esculentum Moench. (common buckwheat) and its wild relative F. homotropicum were produced after controlled pollination and embryo rescue culture. Cross-compatibility was found to be better when thrum-type common buckwheat was used as the female parent rather than the pin-type. The resulting F1 plants were partially fertile, late maturing and intermediate between the parents in flower shape and plant height. They segregated into heterostylic (thrum only) and homostylic types in equal numbers, indicating that homostyly is controlled by a single dominant gene. The thrum-type F1 hybrids were backcrossed to common buckwheat and the progenies were raised utilizing embryo rescue culture. The homostylic F1 hybrids were advanced to the F2 and F3 generations through self-fertilization and utilized, together with the BC1F1, for the analysis of the stylar genes. The results obtained indicate that the genes coding for heterostyly and homostyly are controlled by the multiple allelic gene S. It appears that the pin/thrum complex in F. esculentum is governed by a single genetic locus S with two alleles S and s that control the reaction in Ss (thrum-type) as well as the ss (pin-type) plants, respectively. The homomorphic flower type of F. homotropicum is governed by the allele Sh.. These genes can be characterized by a relationship of dominance, i.e. S > Sh > s. The introgression of F. homotropicum genes into common buckwheat was verified by means of electrophoretic analysis of seed proteins. Key words: Embryo rescue, F. esculentum, F. homotropicum, interspecific hybridization, ovule culture, seed protein
Isolation of protoplasts from viable egg cells of common buckwheat (Fagopyrum esculentum Moench.)
Authors: Woo Sun Hee , Adachi Taiji , Jong Seung Keun , Campbell Clayton G.
Published: April 2011

In vitro fertilization could be useful to overcome the problem of self-incompatibility of common buckwheat. Therefore, experiments were conducted to isolate viable protoplasts from egg cells for use in vitro fertilization. Protoplasts from viable egg cells of common buckwheat were isolated by enzyme treatment followed by mechanical isolation. Incubation of ovules for up to 4 h allowed the boundary wall of the egg cells to become partially digested and the protoplasts of the egg cells came out of the micropylar or chalazal end after squashing with a mean isolation frequency of approximately 30% (6 out of 20 ovules). The egg cell protoplasts were larger than those of the synergids. Key words: Common buckwheat, Fagopyrum esculentum Moench., protoplast, egg cell solation, embryo sac
Predicting potential field seedling vigour of Canadian six-row barley cultivars
Authors: Briggs K. G. , Dunn G. J.
Published: April 2011

Rapid techniques for predicting the field vigour potential of barley seed samples would be very useful for seed-testing laboratories and barley breeders. The objective of this study was to compare two faster laboratory seed-testing methods, tetrazolium chloride reduction (TZ) and carbon dioxide evolution rate (CDE), with the standard, but slow and costly germination resistance (GR) test, for ability to identify cultivar differences in vigour and their relationship to vigour potential in the field. Fifteen six-row barley (Hordeum vulgare L.) cultivars were used in the study, from two seed sources grown in different years, and four replicate assays of all three tests were conducted in controlled conditions at 5, 10, 15 and 20 °C. Field emergence rate (FDE = days to 75% seedling emergence) was also assessed in replicated plot trials grown at Edmonton and Ellerslie, Alberta in 1997, using the same seed sources. Three seeding dates were used at each site to obtain a range of soil temperatures at planting depth from 4 to 18 °C. Significant differences between cultivars were found for TZ, CDE and GR, but not between seed sources, and little or no interaction of cultivar with assay temperature was found. Cultivar performance was relatively similar when assessed by TZ or CDE, at all temperatures. CDE, TZ and GR results from all temperatures and both seed sources were compared by correlation to FDE results for all six planting events (two field sites × three planting dates). High and significant correlations (r > 0.51; sig., P < 0.05) were found for nearly all comparisons of each of CDE, TZ and GR with FDE. For all comparisons with FDE the average correlation for TZ was 0.68, 0.66 for CDE, and 0.69 for GR, with 10% of all possible correlations exceeding 0.80 (all sig., P < 0.05). These results indicate that all three laboratory tests at any temperature were generally effective predictors of the potential field seedling vigour of different barley cultivars. TZ and CDE appear to be useful alternatives to GR for assessing potential field seedling vigour of barley cultivars, and lend themselves to development of automated laboratory assay procedures, not possible for GR. Key words: Germination prediction tests, barley, field correlation
Measuring polyphenol oxidase activity in a wheat breeding program
Authors: Mccaig T. N. , Fenn D. Y. K. , Knox R. E. , Depauw R. M. , Clarke J. M. , Mcleod J. G.
Published: April 2011

High levels of polyphenol oxidase (PPO) have been associated with discoloration of end-use products of wheat, especially certain noodle types. Two whole-seed methods of measuring PPO, one based on 10 mM tyrosine as substrate and the other on 90 mM catechol, were examined and modified to determine their potential as screening tools in large-scale breeding programs. Thirteen spring wheat and two spring triticale genotypes were used to compare the methods. Both methods could measure PPO on individual seeds. All genotypes displayed large seed-to-seed variation for PPO with both substrates. The mean coefficient of variation for the PPO values of individual seeds within genotypes was 39% with tyrosine and 34% with catechol. Furthermore, the PPO values of individual seeds within genotypes were not normally distributed for most genotypes. Identifying genotypes with incremental improvements in PPO would probably require measurement of 70–100 seeds. Approximately 50% of the catecholase activity was associated with the water extract after soaking seeds for 16 h, while all of the tyrosinase activity was still associated with the seed, suggesting that different enzymes are responsible for oxidizing tyrosine and catechol in wheat. While the 10 mM tyrosine assay was nondestructive and allowed plants to be generated from seeds low in PPO, 90 mM catechol reduced germination to less than 20%. Reducing the catechol to 30 mM improved germination to 85%, did not substrate-limit the reaction, and reduced the health risk associated with the assay. Spectral and kinetic differences between the assays were also considered. Key words: Triticum sp., wheat, polyphenol oxidase, catechol, tyrosine
Comparative rooting of deciduous landscape shrub cuttings in media amended with paper mill biosolids from four different sources: Summary
Authors: Chong Calvin , Hamersma Bob , Bellamy Kevin L.
Published: April 2011

not available
Water stress effects on the content of low molecular weight carbohydrates and phenolic acids in Ctenanthe setosa (Rosc.) Eichler
Authors: Ayaz F. A. , Kadioglu A. , Turgut R.
Published: April 2011

Morphological and biochemical changes in plant cells are known as important events for adaptation to stress. In this study, changes in carbohydrate and phenolic acid concentrations during leaf rolling under water stress were investigated. Leaves of vegetatively propagated Ctenanthe setosa (Rosc.) Eichler plants started to roll after a 28-d water deficit. After approximately 33–35 d, the leaves were tightly rolled. Water stress significantly increased the dry weight of rolled leaves. Low molecular dry weight carbohydrate components identified in unrolled and rolled leaves were fructose, glucose, inositol and sucrose. Leaves of stressed plants tended to accumulate more carbohydrates of low molecular weight. The same sugars (except inositol) were also identified in liquid and crystal forms of exudates, which appeared on the abaxial surface of the leaves during leaf rolling. The phenolic acids identified in unrolled and rolled leaves were from the benzoic group (benzoic, salicylic, 4-hydroxybenzoic, vanillic, 3,4-dihydroxybenzoic, syringic acids), and the cinnamic group (ferulic and caffeic acids both in free and methyl ester form and cis- and trans-p-coumaric acids). All phenolic acid concentrations (except for salicylic acid) in the phenolic group increased in rolled leaves in comparison with unrolled leaves. In the cinnamic group, the amounts of cis- and trans-p-coumaric and caffeic acids were greater in rolled leaves than in unrolled leaves. Key words: Ctenanthe setosa, exudate, crystal, leaf rolling, sugar, phenolic acid
Tolerance of common buckwheat (Fagopyrum esculentum) to low rates of 2,4-D and MCPA
Authors: Wall David A. , Smith Marjorie A. H.
Published: April 2011

Field studies were conducted from 1995 to 1997 at Morden and Brandon, Manitoba, Canada, to evaluate the effect of crop growth stage at application on common buckwheat (Fagopyrum esculentum Moench.) tolerance to low rates of 2,4-D amine, MCPA amine and the sodium salt of MCPA. Each formulation was applied at 140 g a.i. ha−1 to common buckwheat at the two- to three-leaf, four- to five-leaf, and six- to eight-leaf stages. Levels of buckwheat injury and seed yield loss were very similar for the three phenoxy herbicide formulations. Although early-season crop injury was severe, injury was often less, and crop recovery from injury greater, when herbicide was applied at the two-leaf stage than at the four-leaf or six-leaf stage. When herbicide was applied at the two-leaf stage, a significant yield reduction occurred in only one of the five trials. However, buckwheat seed yield decreased when phenoxy-herbicide application was delayed past the two-leaf stage. If low application rates of phenoxy herbicides to early stage buckwheat are effective in suppressing weed growth, then this treatment may enable the crop to out-compete weeds without sustaining yield losses in most years. Key words: Common buckwheat, tolerance, crop growth stage, yield, phenoxy herbicide
Seed colour and linolenic acid effects on agronomic traits in flax
Authors: Saeidi G. , Rowland G. G.
Published: April 2011

Solin flax (Linum usitatissimum L.) is an edible-oil crop that must have less than 5% linolenic acid in its seed oil and a yellow seed coat. Seed vigour of solin is often lower than that of brown-seeded linseed flax and this lower seed vigour has been associated with both seed colour and linolenic acid levels. To evaluate the agronomic affect of this relationship, paired near-iso-genic populations of flax differing in seed coat colour and linolenic acid concentration were selected from different crosses and sown in field trials at the Kernen Crop Research Farm, University of Saskatchewan in 1995 and 1996. Seed with brown seed coat colour had higher field emergence and seed yield than yellow-seeded types. However, emergence differences did not contribute to this seed yield variation. Maturity was not affected by seed colour but yellow seed had greater seed oil concentration and mechanical seed coat damage than brown seed. Low linolenic acid seed (2%), compared with high linolenic seed (50%), had lower field emergence in 1995, were later maturing and had higher seed yield. Linolenic acid concentration had no significant effect on oil concentration and seed damage from mechanical harvesting. Solin types had lower field emergence than industrial oil types. There was no difference for seed yield, oil concentration and seed weight between solin and industrial oil types. Solin seed was slightly later maturing and had greater seed coat damage than industrial seed in some genetic backgrounds. Key words: Seed colour, linolenic acid, emergence, seed damage, flax
Breeding summer turnip rape for resistance to brown girdling root rot
Authors: Woods D. L. , Turkington T. K. , McLaren D. , Davidson J. G. N.
Published: April 2011

Screening of 260 Brassica rapa lines resulted in identification of five lines with partial resistance to brown girdling root rot (BGRR). A method for simultaneously selecting for canola quality traits and reduced disease susceptibility was developed and used to screen progeny of crosses to BGRR susceptible canola quality lines. Key words: Turnip rape, Brassica rapa, brown girdling root rot, resistance
Comparison of grain moisture vs. visual observation in selection for early maturity in barley
Authors: Dofing S. M.
Published: April 2011

The purpose of this research was to compare assessments of maturity in barley (Hordeum vulgare L.) using growing degree days to maturity based on visual head color and percent grain moisture. Twelve barley cultivars were evaluated for 3 yr at Palmer, Alaska, using three harvest dates. Phenotypic and environmental correlation coefficients between growing degree days to maturity and grain moisture at harvest were high, and tended to be highest at earlier harvest dates. Key words: Barley, early maturity, selection
AC Melfort field pea
Authors: Warkentin Tom , Xue Allen , Sloan Al , Rashid Khalid , Ali-Khan S. T. , Vera Cecil , Orr Denise , Turkington Kelly , Clayton George , Loeppky Gerald
Published: April 2011

AC Melfort, a yellow cotyledon field pea (Pisum sativum L.) cultivar was released in 1998 by Agriculture and Agri-Food Canada, Morden Research Centre, Morden, Manitoba. AC Melfort has a semi-leafless leaf type, powdery mildew resistance, medium-large round seeds and good yielding ability, particularly in the warmer, drier zone of the prairies. Key words: Field pea, Pisum sativum L., cultivar description, powdery mildew resistance
Rotation crop effects on Pratylenchus penetrans and subsequent crop yields
Authors: Jagdale G. B. , Ball-Coelho B. , Potter J. , Brandle J. , Roy R. C.
Published: April 2011

Root damage from Pratylenchus penetrans causes economic losses in many crops. Rotation with poor or non-hosts is a control method that can reduce the use of fumigant nematicides. Short-term experiments were conducted to identify potential non-host sorghum and millet hybrids. In a field experiment, forage pearl millet (Pennisetum glaucum L. 'CFPM 101'), grain pearl millet ('CGPMH-1'), grain sorghum (Sorghum bicolor L. 'CGSH-7') and rye (Secale cereale L. common) were grown in rotation with tobacco (Nicotiana tabacum L. 'Delfield'), a known intolerant host. One rye treatment was fumigated prior to tobacco planting in 1998. P. penetrans numbers were lower in forage and grain pearl millet plots than in grain sorghum or rye plots in the year of planting. In the subsequent tobacco crop year, root nematode counts in plots where forage and grain pearl millet were grown were similar to counts in fumigated rye plots and lower than counts in plots where non-fumigated rye and grain sorghum were grown. Tobacco leaf yield was negatively correlated with soil nematode counts from November 1997 to July 1998 (r = −0.48, P = 0.0001), as well as with root counts from July 1998 to September 1998 (r = −0.40, P = 0.0015). This is the first report of P. penetrans suppression by P. glaucum in the field. Further investigation of nematode suppression by pearl millet lines and development of this potentially sustainable farming system is warranted. Key words: Pratylenchus penetrans, Pennisetum glaucum, Secale cereale, Sorghum bicolor, biological control, cropping system
AC Abbey hard red spring wheat
Authors: DePauw R. M. , Clarke J. M. , Knox R. E. , Fernandez M. R. , McCaig T. N. , McLeod J. G.
Published: April 2011

AC Abbey, hard red spring wheat (Triticum aestivum L.), is adapted to the Canadian prairies. It is significantly shorter than any of the check cultivars and has solid stems. AC Abbey expressed higher grain yield, earlier maturity, and heavier kernels than AC Eatonia, the solidstem check cultivar. It is resistant to the wheat stem sawfly (Cephus cinctus Nort.) and to prevalent races of common bunt and has moderate resistance to leaf rust and stem rust. AC Abbey is eligible for grades of Canada Western Red Spring wheat. Key words: Triticum aestivum L., red spring wheat, yield, wheat stem sawfly, plant height, maturity
AC Compass navy bean
Authors: Park S. J. , Rupert T.
Published: April 2011

AC Compass navy bean (Phaseolus vulgaris L.) was developed at the Agriculture and Agri-Food Canada Greenhouse and Processing Crops Research Centre (GPCRC), Harrow, Ontario. It has high yield potential, erect plant type and medium-early maturity in southwestern Ontario where it is recommended for areas with 2600 or higher CHU. It was registered by the Canadian Food Inspection Agency (Registration no. 4708) on 11 March 1998. Key words: Phaseolus vulgaris, navy bean, cultivar description, plant type
Effects of red versus white wheat bran on rate of growth and feeding of some stored-product beetles
Authors: White Noel D. G. , Demianyk Colin J. , Fields Paul G.
Published: April 2011

The red pigment in the seed coat of hard red spring wheat is produced by phenolics. Most of the wheats grown in western Canada are hard red spring varieties; however cultivars with a whiter seed coat are being developed for their better milling and baking attributes. Because phenolics serve to protect some plants against insect attack, we compared the susceptibility of white and red spring wheat to attack by stored-product insects. Tenebrio molitor (Tenebrionidae) larvae reared on red wheat bran gained less weight than larvae reared on white wheat bran but this insect has a long developmental period and does not attack sound grain. Tribolium castaneum (Tenebrionidae) pupal weights were not affected by the type of wheat milled products on which the larvae fed. A feeding bioassay showed that red bran did not act as an antifeedant for T. molitor, T. castaneum, or Sitophilus oryzae (Curculionidae). However, it acted as a feeding stimulant for Rhyzopertha dominica (Bostrichidae), which is related to wood-boring insects. It is unlikely that white wheat in storage would be more prone to insect damage than red wheat. Key words: Bran, colour, wheat, phenolics, stored-product insects
Molecular analysis of genetic variation among alfalfa (Medicago sativa L.) and Medicago ruthenica clones
Authors: Campbell T. A.
Published: April 2011

Medicago ruthenica (L.) Ledebour is an allogamous diploid (2n = 2x = 16) perennial indigenous to Siberia, Mongolia and Manchuria with a remarkable ability to survive mechanical and physiological stress. The possibility of hybridizing alfalfa (Medicago sativa L.) and M. ruthenica is being investigated. The objective of the current research was to conduct a molecular assessment of genetic relatedness and inter- and intra-specific genetic variation in cultivated alfalfa (2n = 4x = 32) and M. ruthenica. Seventeen alfalfa clones, selected randomly from the broad-based population W10- AC3, and 17 agronomically superior M. ruthenica clones, tracing to 17 collection sites in Inner Mongolia, were studied using Random Amplified Polymorphic DNA (RAPD), Anchored Microsatellite Priming (AMSP), and Simple Sequence Repeat (SSR) analyses of genomic DNA. Mean genetic distances (GD) within M. ruthenica and alfalfa clones were 0.5 and 0.56, respectively, based on RAPD/AMSP data, and 0.29 and 0.40, respectively, based on SSR data. Alfalfa and M. ruthenica were genetically distant (RAPD/AMSP GD = 0.73); however, this difference does not necessarily preclude the possibility of interspecific hybridization, although the use of techniques such as bridge crossing, embryo culture rescue and/or protoplast fusion may be necessary. Key words: Alfalfa, genetic resources, Medicago ruthenica, Medicago sativa, microsatellite, simple sequence
Comparison of white clover and mixed sodgrass as orchard floor vegetation
Authors: Neilsen G. H. , Hogue E. J.
Published: April 2011

Spartan apple trees on M•26 (Malus domestica Borkh.) rootstock, planted in 1983, were grown for 8 yr (1985–1992) at 60 and 180 kg N ha−1 yr−1 with five orchard floor vegetation management treatments. A white clover cover over the whole orchard floor increased leaf N concentration relative to complete sod cover, but had negative effects on tree vigour and yield. Maximum vigour and yield occurred when in-row weed competition was controlled in a 1.5-m-strip, regardless of orchard floor vegetation beyond the strip. Key words: Apple, leaf N, orchard floor vegetation management, vigour, yield
AC Longview alfalfa
Authors: Acharya S. N. , Huang H. C.
Published: April 2011

AC Longview alfalfa (Medicago sativa L.) was developed by the Agriculture and Agri-Food Canada Research Centre, Lethbridge, Alberta. This cultivar, tested as LRS 93-1 in Uniform Alfalfa Tests in western Canada, is highly resistant to verticillium wilt (VW) and bacterial wilt (BW) and out-yielded Beaver (check) by about 9 and 12% in dryland and irrigated locations, respectively. AC Longview is well suited for hay production, dehydration and silage in areas of western Canada, including British Columbia, where VW or BW reduces alfalfa yield and stand life. This cultivar produces good amount of seed both under dryland and irrigated conditions of western Canada. Key words: Cultivar description, alfalfa, Medicago sativa, disease resistance
Effect of method and time of application of nitrogen fertiliser on yield and quality of seed of creeping red fescue
Authors: Fairey N. A. , Lefkovitch L. P.
Published: April 2011

Six trials were conducted on commercial seed fields of creeping red fescue (Festuca rubra L. var. rubra) in the Peace region to evaluate the sensitivity of seed production to the method and time of application of N fertiliser. In each trial, 68 kg ha−1 N was applied using three methods (surface-broadcast, granular, ammonium nitrate 34-0-0; foliar/soil spray of 28-0-0 solution N; soil-injected 28-0-0 solution N) at each of three times (fall, early spring, late spring). No statistically significant (P = 0.05) interaction, or main effect, of method and time of N were revealed for seed yield, fertile tiller density or for several seed quality characteristics. Seed yield varied greatly among trials (142 to 1240 kg ha−1) and averaged 566 kg ha−1. The results indicate that there is considerable flexibility in the method and time of application of N fertiliser for seed production of creeping red fescue in the Peace region, provided it is applied before the commencement of vigorous plant growth in the spring. Key words: Creeping red fescue, Festuca rubra L., nitrogen fertility, grass seed production, grass seed quality
CG106 corn inbred line
Authors: Lee E. A. , Good B. , Chakravarty R. , Kannenberg L.
Published: April 2011

CG106 is a short-seasoned corn (Zea mays L.) inbred line. CG106's parentage contains unique germplasm. CG106 exhibits average combining ability in hybrids. Key words: Corn, Zea mays L., cultivar description
AC Remington winter rye
Authors: McLeod J. G. , Gan Y. T. , Payne J. F.
Published: April 2011

AC Remington, a cultivar of winter rye (Secale cereale L.), was developed at the Semiarid Prairie Agricultural Research Centre, Research Branch, Agriculture and Agri-Food Canada, Swift Current, Saskatchewan. AC Remington is a semidwarf with 20 to 25% shorter straw and improved lodging resistance compared with tall cultivars. AC Remington has good winter survival and is well adapted to the Canadian Prairies. AC Remington has improved grain yield, test weight, kernel weight and Hagberg Falling Number compared with those of the semidwarf cultivar AC Rifle. Plant height, heading, maturity and ergot infection of AC Remington are similar to those of AC Rifle. Key words: Cultivar description, semidwarf, rye (winter), Hagberg Falling Number, Secale cereale L.
Cross-Canada comparison of the productivity of fodder galega (Galega orientalis Lam.) with traditional herbage legumes
Authors: Fairey N. A. , Lefkovitch L. P. , Coulman B. E. , Fairey D. T. , Kunelius T. , McKenzie D. B. , Michaud R. , Thomas W. G.
Published: April 2011

A study was conducted across Canada to compare the herbage productivity of fodder galega (Galega orientalis Lam.) to that of traditional forage legumes, in order to assess its agricultural potential. Trials were established at latitudes ranging from 45 to 56°N with longitudes from 52°W (St. John's, Newfoundland) to 120°W (Dawson Creek, British Columbia). Herbage productivity was monitored for a maximum of 3 production years. The establishment characteristics of Gale fodder galega were comparable to those of Apica and Beaver alfalfa (Medicago sativa L.) and Altaswede red clover (Trifolium pratense L.), and somewhat superior to those of Dawn Alsike clover (T. hybridum L.) and Leo trefoil (Lotus corniculatus L.). Anik alfalfa (M. falcata L.) was far less uniform and vigorous in its establishment than any of the other species. The average annual dry matter yield of fodder galega ranked third among the seven legumes when averaged over the nine sites; it produced 5545 (SE 95) kg ha−1 compared to 3931 (SE 72) kg ha−1 for Dawn alsike clover, the lowest-yielding crop, and 6673 (SE 114) kg ha−1 for Apica alfalfa, the highest-yielding. The cumulative dry matter yields indicated that Gale galega is at least as well adapted across Canada as the other legumes, except possibly at Saskatoon where the M. sativa alfalfas were far superior to all the other legumes in their ability to establish and thrive. The performance characteristics of Gale fodder galega indicate that it has considerable agricultural potential as an additional, perennial, herbage legume for many regions of Canada, except in the semi-arid continental climate of the central Prairies where its growth may be limited by high air temperature and/or insufficient soil moisture. Key words: Fodder galega, Galega orientalis Lam., goat's rue, herbage production, forage legume
Identification and evaluation of flea beetle (Phyllotreta cruciferae) resistance within Brassicaceae
Authors: Gavloski J. E. , Ekuere U. , Keddie A. , Dosdall L. , Kott L. , Good A. G.
Published: April 2011

All currently registered varieties of canola/oilseed rape, Brassica napus and B. rapa, are susceptible to attack by flea beetles, although to varying degrees. The development of resistant cultivars would be an environmentally acceptable means to reduce the damage caused by flea beetles. Seedlings from 10 species of Brassicaceae were evaluated for levels of antixenosis resistance to flea beetles in the laboratory, along with 308 Sinapis alba/B. napus hybrids. Thlaspi arvense and 11 cultivars of S. alba were resistant to feeding by flea beetles. In addition, 34 S. alba/B. napus hybrids were resistant to feeding by flea beetle in at least one test, although many of these failed to demonstrate resistance with repeated testing. One hybrid line was resistant to feeding by flea beetles each of the four times it was tested, while another was resistant in three out of four tests. These data indicate that resistance to flea beetles within the Brassicaceae is a genetic trait and can be transferred by interspecific hybridization. This information is the first step towards introgression of genetic sources of flea beetle resistance from resistant relatives into canola varieties. Key words: Flea beetles, Phyllotreta cruciferae, Brassica, resistance, antixenosis, introgression
Wind reduces growth and yield but not net leaf photosynthesis of primocane-fruiting red raspberries (Rubus idaues L.) in the establishment years
Authors: Privé Jean-Pierre , Allain N.
Published: April 2011

Four primocane-fruiting (PF) red raspberry cultivars, Bogong, Autumn Cascade, Heritage and Dinkum, were grown in exposed or sheltered (50% permeable artificial windbreak) sites fully exposed to prevailing winds in Bouctouche, NB. Shelters were erected at the beginning and removed at the end of each growing season. In the establishment year, all cultivars were evaluated to determine the effects of wind stress on their vegetative and reproductive development and leaf gas exchange. since all cultivars responded similarly to the effect of wind in year one, only Dinkum was monitored in years two and three. In all years, the artificial windbreak resulted in an overall 35% reduction in wind velocity, increased the number of calm days (<5.4 km h−1) and decreased the incidence of strong breezes (>36 km h−1). Interestingly in this maritime climate, the artificial windbreak did not have much of an effect on altering relative humidity, vapour pressure deficits, or air or soil temperature. Plants from sheltered sites consistently had greater above-ground biomass (especially cane dry weight) and longer cane internodes. For two of the three years, leaf area and yield were also greater in the sheltered sites. Leaf gas exchange parameters (Pn, gs and Ci), expressed per unit of leaf area, did not differ between treatments for most of the season, but the sheltered plants retained more leaf area and thus had the potential to fix a greater amount of carbon than the exposed plants. The larger, sheltered plants produced a more extensive fruiting framework, which resulted in increased yields in both the establishment and subsequent year. It is recommended to shelter raspberry plants from wind in the initial establishment years. Key words: Rubus idaeus L., fall-bearing, autumn fruiting, windbreak
Penicillium bilaii inoculation increases root-hair production in field pea
Authors: Gulden Robert H. , Vessey J. Kevin
Published: April 2011

Under three levels of phosphorus availability, inoculation of pea plants with Penicillium bilaii in growth pouches had no effect on root length (excluding root hairs), mean root diameter, root-hair diameter, P accumulation or shoot growth. However, inoculation with P. bilaii resulted in a 22% increase in the proportion of root containing root hairs and a 33% increase in the mean root-hair length. Key words: Pea, Penicillium bilaii, Pisum sativum, phosphorus, root hairs, root morphology
Comparison of weed communities in Manitoba ecoregions and crops
Authors: Acker R. C. Van , Thomas A. G. , Leeson J. Y. , Knezevic S. Z. , Frick B. L.
Published: April 2011

In 1997, a weed survey was conducted during July and August in fields of wheat, barley, oat, canola and flax in Manitoba. Field selection was based on a stratified-random sampling methodology using ecodistricts as strata. Species in the Poaceae family were most commonly observed in the survey, followed by species in the Polygonaceae, Asteraceae and Brassicaceae families. The six most abundant weed species were green foxtail [Setaria viridis (L.) Beauv.], wild oats (Avena fatua L.), wild buckwheat (Polygonum convolvulus L.), Canada thistle (Cirsium arvense L.), redroot pigweed (Amaranthus retroflexus L.) and wild mustard (Sinapis arvensis L.). The survey highlighted significant differences between ecoregions and between crops in residual weed infestations. The weed community in the Boreal Transition ecoregion was dominated by seven species, whereas fields in the Aspen Parkland and Lake Manitoba Plain ecoregions were dominated by two species and the Interlake Plain ecoregion was dominated by only one species. Although significant differences were found between the weed communities in crops, they were not as great as differences between ecoregions. The Manitoba residual weed community in 1997 was very similar to that reported for 1978–1981 and 1986, suggesting that the same species should remain a focus for weed management. Key words: Weed survey, weed relative abundance, weed distributions, Manitoba ecoregions
Effect of temperature, seeding date, fungicide seed treatment and inoculation with Fusarium avenaceum on seedling survival, root rot severity and yield of lentil
Authors: Hwang S. F. , Gossen B. D. , Turnbull G. D. , Chang K. F. , Howard R. J. , Thomas A. G.
Published: April 2011

Early seeding of lentil is necessary on the northern prairies to ensure that the crop has time to mature. However, planting into cold soils in spring results in slow germination, which may predispose seedlings to infection by soil-borne pathogens. In a controlled-environment study of the impact of temperature on infection of lentil seedlings (cv. Eston) byFusarium avenaceum, root rot symptoms were most severe at warm temperatures (20° to 27.5 °C) and declined in warmer or cooler soils. Field plots were seeded on three dates, which were spaced about 2 wk apart between early May and early June in four station years. Seedling emergence was most consistent and seed yield was highest in three of four sites at the second seeding date. Emergence and yield were substantially lower for the latest seeding date. Inoculation with F. avenaceum reduced establishment and seed yield. Seed treatment with Crown (thiabendazole and carbathiin) improved seedling survival, reduced root rot severity and increased seed yield relative to the inoculated control. Vitaflo-280 (thiram and carbathiin) also improved establishment and yield, but the effect was not as strong or consistent. Treatment with Raxil (tebuconazole) and Apron (metalaxyl) had no effect. The pathogenicity of aggressive isolates of F. avenaceum from lentil on a range of crop species was evaluated. All crops were susceptible to some degree, which indicates that the pathogen, once established, is likely to persist in a field for some time. This study demonstrated that early planting was required for maximum yield, that certain isolates of F. avenaceum were pathogenic on a wide range of hosts, and that seed treatment can be used to minimize losses from seedling blight and root rot in lentil. Key words: Lentil (Lens culinaris Medikus), Fusarium avenaceum, root rot, seeding date, thiabendazole, carbathiin, thiram, tebuconazole
Denitrification and fluxes of nitrogenous gases from soil under steady oxygen distribution
Authors: Cho C. M. , Burton D. L. , Chang C.
Published: April 2011

Transport equations for O2, NO3−, NO2−, N2O and N2 were formulated to investigate NO3− stability, denitrification and formation of gaseous nitrogen compounds in a soil profile under different moisture and temperature conditions. The source-sink terms of the transport equations, including those for O2, were based upon competitive Michaelis-Menten type kinetics of denitrification. The equations were solved under various soil and seasonal temperature conditions typical of the Prairie Region of Canada in order to explore the effects of these parameters upon predicted NO3− stability, denitrification product distribution in a soil profile and gaseous N fluxes from the soil surface. The depth to the aerobic-anaerobic interface from the soil surface was controlled by temperature, moisture and microbial activity distributions in the soil. The kinetic expressions predicted that NO3− was generally stable under aerobic conditions since the affinity coefficient of O2 for electrons is much greater than that of NO3−. However, nitrate in the anaerobic zone was subject to denitrification to produce N2O and N2. The N2O produced in the anaerobic zone diffused into the aerobic zone where it was stable and eventually emitted to the atmosphere. As the NO3− concentration decreased, a greater proportion of N was emitted to the atmosphere as N2. Thus, the ratio of N2O to N2 emitted from the soil decreased with decreased NO3−. We found that the potential for denitrification to take place in a soil profile was actually greater in late summer than in mid-summer since subsoil temperatures were higher later on in the season. The ratio of fluxes of N2O to N2 was a function of time, moisture content distribution, the depth at which the maximum reduction of NO3− took place, and NO3− concentration.

Key words: Transport, denitrification, gas flux, nitrous oxidenot available
Low tension water flow in structured soils
Authors: Lin H. S. , McInnes K. J. , Wilding L. P. , Hallmark C. T.
Published: April 2011

Water transport through structured clayey soils may be prone to by-pass flow, a mechanism that may lead to rapid transport of contaminants to ground water. To quantify the significance of low-tension water flow in structured soils, apparent steady-state infiltration rates at water potentials from −0.24 to 0 m were measured using tension infiltrometers on 18 soils of varying texture and structure. Each infiltration measurement was conducted sequentially at −0.24, −0.12, −0.06, −0.03, −0.02, −0.01, and 0 m supply potentials (Ψsupply), all at the same soil location, to separate different size pores effective in transmitting water. Results from 96 soil horizons showed that 76 ± 18% (mean ± SD) of the water fluxes at Ψsupply = 0 m (total water flux) were transmitted through macropores (active at Ψsupply ≥ −0.03 m), although macropores usually constituted a small portion of a soil's total porosity. Mesopores (active at Ψsupply ≥ −0.24 m) contributed 19 ± 13% of total water flux. Micropores dominated the soils' total porosities, but generally contributed <10% of the total water flux. Macropores and mesopores showed greater influence on water flow in clays than in sands at Ψsupply ≥ −0.24 m. Values of soil macroscopic λc and microscopic λm capillary length scales were determined from the change in infiltration rates with Ψsupply. Values of λc, a hydraulic conductivity-weighted mean capillary water potential, were greater for sands (63 mm) than loams (50 mm), and greater for loams than clays (22 mm). Values of λm, the mean hydraulically effective pore size, were greater for clays (0.33 mm) than loams (0.15 mm), and greater for loams than sands (0.12 mm). Most of the soils studied showed hydraulic characteristics associated with by-pass flow. Key words: Infiltration, tension infiltrometer, macropore flow, by-pass flow, capillary length scale, α parameter