bluuebunny/crossref_metadata_2025 huggingface dataset:
THE GENETIC ANALYSIS OF TWO INTERSPECIFIC SOURCES OF LEAF RUST RESISTANCE AND THEIR EFFECT ON THE QUALITY OF COMMON WHEAT
Authors: DYCK P. L. , LUKOW O. M.
Published: March 2010

Gene Lr29 transferred from Agropyron elongatum to chromosome 7D of wheat and gene LrVPM transferred from VPM1 both segregated as single genes for seedling resistance to leaf rust when backcrossed into common wheat (Triticum aestivum). Although the seedling resistance of the VPM lines was intermediate, their adult plant resistance was excellent. This resistance was not on chromosome 7D. The VPM lines also had seedling and adult plant resistance to stem rust. Resistant backcross lines with either Lr29 or LrVPM had higher kernel protein levels than did susceptible sister lines under both rust and rust-free conditions. Although this higher protein content was associated with weaker dough mixing properties, the remix loaf volume remained constant. Leaf rust infection had a detrimental effect on grain yield and kernel weight and on wheat quality as shown by decreased kernel protein content and farinograph absorption. Dough mixing strength was higher for the rust infected lines than the rust resistant lines.Key words: Triticum aestivum, wheat (spring), leaf rust resistance, protein content, breadmaking quality
EFFECTS OF FUMIGATION AND FERTILIZER ON GROWTH, YIELD, CHEMICAL COMPOSITION, AND MYCORRHIZAE IN WHITE BEAN AND SOYBEAN
Authors: BUTTERY B. R. , PARK S. J. , FINDLAY W. I. , DHANVANTARI B. N.
Published: March 2010

Plant dry weight of samples taken during the 1984 growing season, and seed yield of white bean (Phaseolus vulgaris L.) in 1986, increased with an increase in N fertilizer. Soybean (Glycine max (L.) Merr.) did not respond to N level except for a depression of nodule weights with increase in fertilizer N, which also occurred in white bean. Soybean had a greater weight of nodules, which formed a higher proportion of plant dry weight than in white bean, especially at high N levels. Soil fumigation reduced nodule weights of both species at 38 d after seeding (DAS) and of soybean at 64 DAS. Fumigation also reduced vesicular arbuscular mycorrhiza (VAM) in both species. Fumigation lowered P concentration in leaf tissue of both species in −PK plots but not in +PK plots. Fumigation increased seed yield in +PK plots, but lowered yield in −PK plots. Reduction of competition from other soil micro-organisms by fumigation did not improve nodulation. The effects of fumigation on yield could be explained by destruction of the VAM, which were beneficial in −PK plots (by aiding uptake of P), but were not beneficial in +PK plots.Key words: Soybean, bean (white, common), nitrogen, phosphorus, mycorrhiza, nodulation
GENETIC VARIABILITY IN THE PHYSICAL PROPERTIES AND OTHER QUALITY TRAITS OF TIMOTHY
Authors: SURPRENANT J. , MICHAUD R.
Published: March 2010

The breeding of timothy (Phleum pratense L.) is mainly targetted at improving the nutritive value of the crop. Three physical properties, packed volume (PV), water retention (WR) and water solubility (WS) have been suggested as indirect measurements of voluntary intake. Variation for these three traits was estimated at the early heading and the flowering stages for 2 consecutive years within four timothy populations (Itasca, Labelle, Pronto and Richmond). Significant genetic variation was observed for PV, WR, WS, plant height (PH), dry matter yield (DMY), crude protein (CP), and digestibility (IVDMD) but the magnitude of the variation was inconsistent among populations. Curiously, PV, WR and WS seemed to improve from early heading to flowering. Significant variation was observed in all four populations for PV, in three populations for WS and in only two populations for WR. The different interactions between genotypes, years and maturities indicated that different selection strategies might be needed according to the base population used. The correlations within and between maturity stages among PV, WR, WS, PH, DMY, CP and IVDMD were inconsistent among populations. The presence of genetic variation in timothy for the three physical properties under study suggests that improvement of these traits may be possible through breeding. However, further information is needed on the heritability and the evolution of these traits with advancing maturity.Key words: Timothy, Phleum pratense L., packed volume, water retention, water solubiliy, forage quality
YIELD AND NUTRIENT CONTENT OF SUMMER- AND FALL-GROWN FORAGE Brassica CROPS
Authors: GUILLARD K. , ALLINSON D. W.
Published: March 2010

A series of experiments was conducted in which summer- and fall-grown Brassica species were evaluated for production of dry matter and nutritive value. Species that possessed edible roots produced the highest yields of dry matter and estimated digestible energy in either season. Summer totals were higher than fall totals. Turnip (Brassica rapa L.) root yields were greater and contributed more to total dry matter yields than either swede (Brassica napus L.) or a Brassica hybrid, Tyfon [Brassica rapa L. × Brassica pekinensis (Lour.) Rupr.]. In all species, dry matter content of herbage was low (65–175 g kg−1), while digestibility values were high (> 840 g kg−1). Concentrations of neutral-detergent and acid-detergent fiber, acid-detergent lignin, and hemicellulose were generally higher in summer-grown species than in fall-grown species. Based on fiber values, digestible energy content of the foliage and roots was estimated and the values of all species were 12 MJ kg−1 or greater. Seasonal differences in herbage constituents were particularly evident for rape (Brassica napus L.) and kale (Brassica oleracea L. var. acephala DC). Under fall conditions, species differences were less than differences over summer conditions. Higher light intensities and temperatures over summer-growing conditions appear to promote greater production of dry matter and structural components in these crops compared to similar growth periods over fall conditions. Brassica spp. can be used as supplemental or alternate forage crops.Key words: Brassica spp., yield, digestibility, fiber, energy
INFLUENCE DU STADE DE CROISSANCE SUR LE RENDEMENT, LA COMPOSITION CHIMIQUE ET LES RÉSERVES NUTRITIVES DU LOTIER CORNICULÉ
Authors: GERVAIS PAUL
Published: March 2010

A 3-year study on the stages of growth of birdsfoot trefoil (Lotus corniculatus L.) at harvest showed that the dry matter yield increased significantly, in the spring growth, with advance in maturity up to the midbloom stage. The highest annual yield was obtained, however, when birdsfoot trefoil was harvested at the full bloom stage both in the spring and summer growth. Maximum protein yield per unit of land was also obtained at the full bloom stage. In the spring forage, the percentages of crude protein, cell content, cell wall, lignocellulose, lignin, cellulose, ash and phosphorus and in the summer forage, the percentages of crude protein, lignocellulose, cellulose, ash and phosphorus decreased significantly with maturity. For all other constituents in both forages, the variations did not reach the level of significance. The accumulation of food reserves in the roots of birdsfoot trefoil in the fall was not influenced by the stages of growth at harvest.Key words: Lotus corniculatus L., growth stage, nutrient reserves, dry matter yield, forage quality, birdsfoot trefoil
ALLELOPATHIC ACTIVITY OF QUACKGRASS (Agropyron repens) EXTRACTS AND RESIDUES ON ALFALFA (Medicago sativa)
Authors: TOUCHETTE R. , LEROUX G. D. , DESCHÊNES J. M.
Published: March 2010

Experiments were conducted to characterize the allelopathic activity of quackgrass on alfalfa. Both percent germination and seedling length of alfalfa were recorded to evaluate the toxicity of aqueous extracts from rhizomes or shoots of field-grown quackgrass harvested at three stages of growth in 1984 and 1985. The length of alfalfa seedlings was more sensitive to extracts than was percentage of germination. Aqueous solutions simulating levels of salinity, cyanide content and osmotic pressure equivalent to those found in quackgrass extracts did not affect the growth of alfalfa seedlings. Only quackgrass extracts were phytotoxic to alfalfa. Similar results with hot and cold extraction procedures demonstrated that temperature did not influence the release of water-soluble toxins. Shoot extracts were generally more toxic than were rhizome extracts. Shoot extracts were more inhibitory to alfalfa seedlings when quackgrass was harvested at the vegetative stage than at later stages. Rhizome extracts did not influence the germination of alfalfa, whereas shoot extracts of vegetative quackgrass did in 1985 but not in 1984. The tolerance of alfalfa to rhizome and shoot extracts differed among eight alfalfa varieties. Incorporation of rhizome and shoot residues into the soil caused a similar level of yield reduction, whereas peat moss residues did not influence alfalfa yield. When quackgrass residues were incorporated into soil at various times before seeding, the yields of alfalfa were progressively reduced as the period of incubation was shortened. The incorporation of peat moss did not reduce the yield of alfalfa at any periods.Key words: Allelopathy, quackgrass, alfalfa, aqueous extracts, plant residues, Agropyron repens
VARIABILITY AND HERITABILITY OF EXCISED-LEAF WATER RETENTION CAPABILITY IN ORCHARDGRASS
Authors: PREMACHANDRA G. S. , SHIMADA T.
Published: March 2010

A simple experimental procedure was developed to measure the excised-leaf water retention capability (ELWRC) of orchardgrass. Broad-sense heritability of 59.8% was estimated for ELWRC using a ratio of pertinent variance components. The results suggested that ELWRC is likely a quantitative character which is determined by both genetic and environmental effects.Key words: Drought tolerance, Dactylis glomerata, broad-sense heritability
ORION FABA BEAN
Authors: BERKENKAMP B. , MEERES J.
Published: March 2010

Orion is an early-maturing, small-seeded faba bean (Vicia faba minor) cultivar developed by Agriculture Canada. Orion is adapted to the short-season areas of the park-lands of Western Canada, where it produces higher seed yield than other cultivars.Key words: Cultivar description, faba bean, Vicia faba L.
EFFECTS OF 2,4-D AND DICAMBA TIME OF APPLICATION ON BROMEGRASS SEED PRODUCTION
Authors: DARWENT A. L. , SMITH J. H.
Published: March 2010

2,4-D at 0.5 and 1.0 kg a.i. ha−1 and dicamba at 0.15–0.60 kg a.i. ha−1 were applied to bromegrass (Bromus inermis Leyss.) in September of the year of seeding or in the following spring at each of two crop stages: before stem elongation and the shot-blade. Seed yields 1 yr after seeding were not significantly reduced by any of the herbicide treatments applied in September or by any of the 2,4-D treatments applied before stem elongation. However, seed yields, averaged across the 3 yr of the study, were significantly reduced by applications of 2,4-D at 1.0 kg a.i. ha−1 at the shot-blade stage and by all spring applications of dicamba, except the 0.15 kg a.i. ha−1 rate applied before stem elongation. Weight per 100 seeds and percent germination were not affected by any of the herbicide treatments.Key words: Bromegrass (seed), 2,4-D, dicamba
USE OF THE EXCISED SHOOT ASSAY TO EVALUATE RESISTANCE TO Phytophthora cactorum OF APPLE ROOTSTOCK CULTIVARS
Authors: UTKHEDE R. S. , QUAMME H. A.
Published: March 2010

The excised shoot assay was used to evaluate crown and root rot (P. cactorum (Leb & Cohn) Schroeter) resistance of several apple (Malus domestica Borkh.) rootstock cultivars using relative lesion length as a measure of resistance. To determine the best time to assess crown rot resistance, three cultivars, M.26 (moderately resistant), MM.111 (moderately susceptible) and MM.106 (susceptible) were tested monthly for a 12-mo period. The best separation of the three cultivars of known resistance was from the period of February to June and again in November. In another test on 27 apple root-stock cultivars tested quarterly, good separation of known standards was achieved only on the April sampling date. In both tests the organism appeared to overwhelm resistance of the tissue during the most active stage of shoot growth in July and August. Based on the mean for the three dates (April, October and January) the cultivars P. 16, J9, P.2, M.4, 0.3, P.1, M.9, M.26, P.22 and P.18 were significantly more resistant than the field-susceptible rootstocks, MM.106. None was significantly more resistant than M.9 and M.4, the resistant standards.Key words: Crown rot, Malus domestica Borkh, root rot, P. cactorum, rootstocks, apple
EFFECT OF TEMPERATURE AND SOIL MOISTURE ON TIME OF EMERGENCE OF TOMATOES AND FOUR WEED SPECIES
Authors: WEAVER S. E. , TAN C. S. , BRAIN P.
Published: March 2010

The relative times to emergence of seedlings of tomato (Lycopersicon esculentum L.) and four weed species were compared at five alternating temperatures and five levels of available soil moisture in a growth chamber. Weed seeds were sown either on the soil surface or 1.5 cm below it. A cumulative distribution function was used to describe the time required for emergence under a given set of conditions. Time to 50% emergence, base temperatures and accumulated degree days required for 50% emergence were calculated for each species. In general, total emergence decreased as soil moisture decreased, but the species differed in the optimum temperature for emergence. Time to 50% emergence decreased with increasing temperature and increased slightly with decreasing soil moisture. Base temperatures and thermal times required for 50% emergence varied among species, but were relatively insensitive to soil moisture above a critical level. Differences in relative times to emergence of crop and weeds in response to temperature can be used to suggest optimal crop sowing dates and to estimate potential crop yield losses.Key words: Germination, Solanum ptycanthum, Amaranthus powellii, Setaria viridis, Chenopodium album, Lycopersicon esculentum
NITROGEN FERTILIZATION AND PETIOLE TISSUE TESTING IN PRODUCTION OF WHOLE SEED TUBERS OF THE POTATO CULTIVARS SEBAGO AND ATLANTIC
Authors: MacMURDO W. , PRANGE R. K. , VEINOT R.
Published: March 2010

Field plots of Atlantic and Sebago potatoes (Solanum tuberosum) grown for whole seed potato production received five nitrogen treatments at planting (kg N ha−1): 0, 33, 66, 99 and 132. Petiole NO3-N concentrations were determined every 3 wk during the growing season. Supplemental nitrogen (42 kg N ha−1) was applied to the 33, 66, and 99 kg N ha−1 plots when the petiole NO3-N dropped below 1.5%. Both cultivars were harvested 90 d after planting. At harvest, Sebago had more tablestock size (> 70 mm) tubers whereas Atlantic had more seed size (< 70 mm) tubers. The optimum amount of nitrogen applied at planting was between 99 and 132 kg N ha−1 for production of seed tuber number and weight, depending on the cultivar. The petiole NO3-N concentrations increased with the amount of N applied at planting and all N treatments showed declining concentrations during the growing season. In general, Sebago had higher NO3-N concentrations than Atlantic. Supplemental nitrogen application using 1.5% as the critical petiole NO3-N value slowed the decline in petiole NO3-N but did not demonstrate conclusively that it improved tuber number or weight. Critical petiole NO3-N concentrations for Atlantic and Sebago potatoes are proposed.Key words: Nitrogen, Solanum tuberosum, petiole testing, seed tuber, potato
FIELD EVALUATION OF A MODIFIED AUGMENTED DESIGN (TYPE 2) FOR SCREENING BARLEY LINES
Authors: MAY K. W. , KOZUB G. C. , SCHAALJE G. B.
Published: March 2010

The modified augmented design, which adjusts for environmental heterogeneity when large numbers of test lines are being evaluated in nonreplicated plots, was used in a barley (Hordeum vulgare L.) breeding program at two locations in 3 years. The design offered advantages in flexibility of field operations and was satisfactory for statistical preparation and analyses of the tests. Adjustments in yield based on either the row-column effects or covariance were required in the majority of tests. The relative efficiencies verified the choice of adjustment method indicated by the analysis of variance in 12 of 19 tests. The average change in rank of test lines due to adjustment was often large whereas the average change in yield was generally less than 8%. The design has definite advantages for screening barley breeding lines; however, the agreement between rankings of lines based on the adjusted values and the best estimate of their true ranking needs to be investigated.Key words: Modified augmented design, Hordeum vulgare, barley, screening
ABILITY OF THE CANADIAN GRADING SYSTEM TO SEGREGATE CANADIAN WHEAT BY ALPHA-AMYLASE LEVELS
Authors: KRUGER J. E. , BABB J. C. , MORRIS L. J. , TIPPLES K. H.
Published: March 2010

A survey of falling number values in carlots of most classes of wheat (Triticum aestivum L.) was undertaken between October 1985 and February 1986. The purpose was to assess the effectiveness of the present visual grading system for segregating wheat by α-amylase levels as indicated by the falling number method. In addition, the survey was used to pinpoint areas of the western Canadian prairies from which sprout-damaged wheat originated. CWRS wheat had increasing amounts of α-amylase (lower falling number values) with lower grade. The values obtained for a given grade remained relatively constant over the entire testing period. Furthermore, the interdecile range in falling number values for the samples in a particular grade was only around 110 s. Other classes of wheat (CPS, CWSWS, CWRW) exhibited lower falling number values than CWRS wheat, reflecting increased susceptibility to preharvest sprouting and/or different tolerances for maximum percentage of sprouted kernels. Over the testing period, certain grades of some classes also varied more than CWRS wheats in falling number values. The interdecile range in values for these classes was very large and there was considerable overlap in falling number between grades. This suggests that some form of α-amylase testing could be used to advantage for these classes of wheat to ensure more consistent and uniform quality.Key words: Wheat, alpha-amylase, grading, falling number
FIELD PERFORMANCE AT SALINE-AFFECTED SITES OF A SOMACLONAL VARIANT OF McGREGOR FLAX SELECTED FOR SALT TOLERANCE IN VITRO
Authors: ROWLAND G. G. , McHUGHEN A. , McONIE C.
Published: March 2010

The response to salinity of a tissue culture derived, salt-tolerant selection (STS) of flax (Linum usitatissimum) was measured at three saline-affected field sites in Saskatchewan in 1985 and 1986. Two experiments were conducted at each site in each year. Experiment A compared the plant population, dry matter yield and seed yield of STS to its parent cultivar McGregor. Experiment B compared the plant establishment, growth rates, days to flower, days to mature and seed yield per plant of STS, McGregor and the cultivar Noralta which has a maturity similar to STS. The seed yield of McGregor was greater than that of STS in both saline and nonsaline conditions and was significantly less affected by salinity than STS. However, when equal numbers of seeds were sown, more STS plants survived to maturity than either McGregor or Noralta. The decrease in seed yield per plant with increasing salinity was usually greater for McGregor and Noralta than STS and sometimes significantly so. The maturity differences among McGregor, STS and Noralta were not correlated with the differences in seed yield per plant. There was no consistent pattern in the results to suggest that STS was more saline-tolerant than were flax cultivars developed using conventional breeding procedures.Key words: Linum usitatissimum, somaclonal variation, salinity response
DIFFERENTIAL ALUMINUM TOLERANCE OF HIGH-YIELDING, EARLY-MATURING CANADIAN WHEAT CULTIVARS AND GERMPLASM
Authors: BRIGGS KEITH G. , TAYLOR GREGORY J. , STURGES IAN , HODDINOTT JOHN
Published: March 2010

Twenty-eight spring wheat (Triticum aestivum) cultivars were tested for tolerance to aluminum (Al) using solution culture techniques. Fourteen of these cultivars were also grown in the field under two different management levels, Conventional and Intensive Crop Management (ICM), to determine maximum yield potentials in the Edmonton region and to determine if individual cultivars respond differently to management levels on high fertility fallow conditions. Based upon a root weight index (RWI), seven of the 28 spring wheat cultivars tested (K.Kongoni, PT741, K.Nyumbu, PT726, Norquay, PF7748, Maringa) were more tolerant to Al than the winter wheat standard for Al tolerance, Atlas 66. The winter wheat standard for Al sensitivity, Scout 66, ranked most sensitive to Al, but 11 spring wheat cultivars were equally sensitive (Lancer, Wildcat, Columbus, Park, Bluesky, Kenyon, Benito, BW92, Neepawa, Conway, Katepwa). In the field, cultivars varied in yield potential and days to maturity in both the Conventional and ICM treatments; however, ICM provided no additional benefit in terms of yield. Six genotypes (Bluesky, Norquay, Oslo, PT726, PT741, PT742) were significantly higher yielding than Neepawa and matured as early as Park. Six of the nine highest yielding cultivars from the field trials had Al tolerance ratings (RWI values) greater than 0.80 (80% of control), while five Canadian Western Red Spring (CWRS) cultivars, the lowest yielding from the field trials, had RWI values less than or equal to 0.43. The reason for the apparent association between high yield potential and tolerance to Al is unknown.Key words: wheat, Triticum aestivum, aluminum tolerance, high yield, early maturity, intensive crop management
TILLERING PATTERNS OF SPRING WHEAT GENOTYPES GROWN IN A SEMIARID ENVIRONMENT
Authors: HUCL P. , BAKER R. J.
Published: March 2010

Replicated field trials were conducted for 2 yr at two locations in a semiarid short-season environment to compare the tillering patterns of three spring wheat genotypes. Neepawa (high tillering), Siete Cerros (low tillering) and M1417 (oligoculm) were evaluated at five seeding rates (40–640 seeds m−2). Genotypes, locations, years, and seeding rates had significant effects on tiller appearance rate (TAR), maximum tiller number (TMAX), days to TMAX (DTMAX), tiller senescence rate (TSR), tiller mortality (TM) and number of spikes (SN). Genotype × seeding rate and/or year × genotype interactions were detected for TAR, TMAX, TSR, TM and SN. For Siete Cerros, TAR and TSR were constant proportions of those for Neepawa over the four lowest seeding rates. In contrast, TAR and TSR for M1417 increased in proportion to those for Neepawa with increased seeding rate. Similar relationships were observed for TMAX and SN in 1984, but not in 1985. Siete Cerros had higher TM than Neepawa and M1417, especially at low seeding rates. Changes in genotype rank from one seeding rate to another were observed for TAR, TMAX, TSR, and TM, but not for SN. Changes in rank suggest that different tillering patterns may be better suited to different growing environments.Key words: Wheat (spring), tillering patterns, seeding rates
PREDICTION OF THE MOISTURE CONTENT OF EASTERN CANADIAN CORN USING MEASUREMENTS OF CAPACITANCE AND TEST WEIGHT
Authors: BABB J. C. , DEMPSTER C. J. , WALLIS R. J.
Published: March 2010

A statistical regression model for rapid prediction of moisture content based on measurements of dielectric capacitance and test weight was developed for eastern Canadian corn (Zea mays L.). For 336 samples of the 1986 crop, dielectric readings were determined with a Model 919 grain moisture meter, test weight values with an Ohaus half-litre measure and moisture content values by a single-stage air-oven procedure. The regression model, which incorporates linear terms for dielectric reading and test weight plus an interaction term which is a product of the two, is an excellent predictor of corn moisture as indicated by analysis of the residuals and by the high value of the coefficient of determination (R2 = 0.95) and low value of the standard error of estimate (SEE = 0.85). Although the relationship between moisture content and dielectric reading for Ontario samples differed from that for Quebec samples, the proposed regression model helped to compensate for the difference. This model was also effective in predicting moisture content for 365 samples of 1987-crop eastern Canadian corn. As well, it yielded a better fit to 1986–1987 crop data than did the dielectric-based regression model used in CGC Corn Moisture Conversion Table No. 9.Key words: Zea Mays L., predicting corn moisture, Model 919 meter, capacitance, test weight, dielectric
EFFECT OF HARVEST DATES ON YIELD AND COMPOSITION OF FORAGE KALE
Authors: KUNELIUS H. T. , HALLIDAY L. J. , SANDERSON J. B. , GUPTA U. C.
Published: March 2010

Forage kale (Brassica oleracea L. ’Maris Kestrel’) was sown on 27 May and harvested at 18- to 22-d intervals between 16 Sept. and 6 Dec. in 1985 and 1986. Dry matter accumulated until early November and then declined at about 19 kg ha−1 d−1 until the final harvest. In vitro digestibility of dry matter (IVDDM) ranged from 916 to 952 g kg−1 among harvest dates. Crude protein was similar for most harvest dates. Hemi-cellulose content decreased in 1985 but not in 1986 while cellulose content decreased in 1986 but not in 1985. Lignin content increased from 25 to 43 g kg−1 between mid-September and early December. The cell content peaked at 814 g kg−1 in mid-November. There was an increase in S-methylcysteine sulphoxide (SMCO) concentration of leaves from 1.4 g kg−1 to 6.2 g kg−1 between the first and last harvest dates. Potassium concentrations increased in 1985 and decreased in 1986 from September to December while concentrations of P and S were not influenced by harvest dates. With later harvests, both Ca and Mg concentrations decreased while B decreased in 1985 but not in 1986. Zinc concentrations peaked in October in 1986 while in 1985 they were similar for the five harvest dates. Iron concentrations fluctuated in the two years while Cu and Mn concentrations were not influenced by harvest dates. Forage kale provided highly digestible dry matter in late season. The mineral composition of kale was adequate with the exception of Cu, Mn and Zn which would not satisfy the dietary requirements of ruminants. The SMCO concentrations in kale leaves increased steadily from mid-September to early December but were lower than those concentrations considered deleterious to animal health.Key words: Brassica oleracea L., crude protein, hemicellulose, cellulose, SMCO, macronutrients
INFLUENCE OF POPULATION ON WHITE LUPIN MORPHOLOGY AND YIELD
Authors: CLAPHAM WILLIAM M. , ELBERT-MAY DIANE
Published: March 2010

The influence of plant population on sweet white lupin (Lupinus albus L. ’Ultra’) growth and production were investigated during 1985 and 1987. In 1985, white lupin was sown at populations of 11, 20, 44 and 178 plants m−2, and in 1987 populations of 20, 44, and 100 plants m−2. Plant density had a significant influence on seed and total plant yields and yield components. Seed yields ranged between 2182 and 3708 kg ha−1, and total plant forage yields (at maximum LAI) ranged between 2044 and 11 501 kg ha−1 at populations of 11 to 178 plants m−2. Main-stem and lateral pods, seed pod−1, potential fruiting sites and lateral branch number were inversely proportional to plant density. Lateral pod production was more sensitive to population pressure than main-stem pod production. The number of lateral pods plant−1 was a linear function, whereas the number of main-stem pods plant−1 was a curvilinear function of the inverse of plant population.Key words: Lupinus albus, L. ’Ultra’, physiologic maturity, flower and fruit potential, lupin
INFLUENCE OF TIME OF EMERGENCE AND PLANT DENSITY ON GROWTH OF HEMP-NETTLE (Galeopsis tetrahit)
Authors: LÉGÈRE ANNE , DESCHÊNES JEAN-MARC
Published: March 2010

The effects of time of emergence and plant density on hemp-nettle growth (Galeopsis tetrahit) were measured in natural field populations from the Québec City region and in a greenhouse experiment. In the field, more than 80% of the plants emerged during a peak period of about 2 wk in early May. Few hemp-nettle plants emerged after this peak period. Late-emerging plants produced relatively little biomass compared to plants that had emerged during the early emergence flush. Total biomass accumulation increased with density on three out of four sites. Stands from the lowest density (80 plants m−2) generally produced less biomass than stands of higher plant densities. Average plant biomass production decreased with increasing density. Plants from low density stands displayed a bushy profile compared to the etiolated, single-stemmed plants from high density stands. Mature hemp-nettle stands did not develop strong hierarchical population structures such as found for other annual broadleaf species. Hemp-nettle plants within a stand were distributed rather evenly over a number of height classes. A large proportion of the total biomass was produced by a relatively considerable number of plants 45–59 cm in height rather than by a few dominating individuals.Key words: Hemp-nettle, Galeopsis tetrahit, weed populations, emergence pattern, population density, population structure
WEED CONTROL DURING CICER MILKVETCH ESTABLISHMENT AND YIELDS IN SUBSEQUENT YEARS
Authors: MOYER J. R.
Published: March 2010

Cicer milkvetch was established in 1978, 1979, and 1981 on irrigated land at the Lethbridge Research Station. Weed control treatments were applied only during the establishment year (year 1). Treatments included none (check), barley companion crop, trifluralin, EPTC, diclofop, 2,4-DB, combinations of bromoxynil with trifluralin and EPTC, and combinations of 2,4-DB with diclofop and sethoxydim. In year 1, herbicide treatments increased cicer milkvetch yields but cicer milkvetch yields remained less than 100 g m−2 even when there was a substantial reduction in total weed yield due to herbicide treatments. In year 2, cicer milkvetch yields were greater in all herbicide treatments than in the check. For experiments established in 1978 and 1981 forage yields in year 2 averaged about 50% in weed content when cicer milkvetch was established without weed control, compared with 6% when herbicides were applied. Thus, herbicide treatments were required in year 1 for the production of acceptable forage in year 2. In all experiments, by year 4 cicer milkvetch contributed more than 67% of the total yield and the remainder was mainly dandelions and perennial grasses. Weed control treatments in year 1 had little effect on cicer milkvetch, dandelion, or perennial grass yields by year 4.Key words: Astragalus cicer, trifluralin, EPTC, dandelion
A BIOASSAY FOR EFFECTS OF SOYBEAN ROOT EXTRACTS ON SOYBEAN NODULATION AND ROOT GROWTH
Authors: GAWIENOWSKI MARGARET C. , PETERSON JAY B.
Published: March 2010

A bioassay procedure was developed using a modified Leonard jar system to test effects of soybean (Glycine max ’Clay’) root extracts and the absorbent polyvinylpolpyrollidone on soybean root growth and nodulation from Bradyrhizobium japonicum. Root growth and root browning were affected and were correlated with nodule number.Key words: Glycine max nodulation, polyvinylpolypyrollidone, root extracts
ESTABLISHMENT OF A REDHAVEN PEACH ORCHARD WITH Pratylenchus penetrans-INFESTED AND NONINFESTED ROOTSTOCKS IN A FUMIGATED AND NONFUMIGATED NIAGARA SOIL
Authors: OLTHOF Th. H. A. , POTTER J. W. , JOHNSON P. W.
Published: March 2010

Redhaven peach (Prunus persica (L.) Batsch) trees, grafted on the rootstocks Bailey, Siberian C, or Harrow Blood, with roots free of, or infested by, root-lesion nematodes (Pratylenchus penetrans) were planted in fumigated or P. penetrans-infested Vineland fine sandy loam at Jordan Station, Ontario. Tree growth and soil nematode population densities were monitored for 6 yr. In general, fumigation suppressed soil populations of P. penetrans during the first 4 yr, whereas no consistent nematode control was obtained through the use of nematode-free rootstock. The rootstock Siberian C supported larger numbers of P. penetrans than the other two rootstocks throughout the experiment, whereas Bailey favored the build-up of the pin nematode (Paratylenchus projectus). Tree diameter of nematode-free rootstock was greatest in the first 3 yr only; soil fumigation alone increased growth during the first year only. Tree mortality tended to be lowest in fumigated soil planted to clean rootstocks. Harrow Blood showed the highest mortality; Siberian C the lowest. The data suggest that only nematode-free peach trees should be planted. Orchards should be fumigated if P. penetrans exceeds 800 kg−1 of soil and/or when there is a history of replant failure on a light-textured soil.Key words: Prunus persica, pin nematode, Paratylenchus projectus, replant problem, rootstocks, fumigation
LEAF NUMBER ESTIMATION FROM SHOOT DRY WEIGHT MEASUREMENTS FOR TWO TURFGRASS SPECIES
Authors: WRIGHT C. P. M. , EGGENS J. L. , CAREY K. , HINES R. J.
Published: March 2010

The objective of this study was to determine if total plant leaf numbers in a large data set could be predicted from individual plant shoot dry weight measurements using regression equations derived from a subset of the data. The species used were annual bluegrass (Poa annua L.) and creeping bentgrass (Agrostis palustris Huds. ’Penncross’). There was significant correlation between leaf number and shoot dry weight measurements in data subsets. Leaf numbers for the total data set were estimated by the regression equation derived from a subset consisting of pooled data from one, two or three replicates. This procedure was assessed by comparing predictions from regression equations with actual values, using a number of different sets of replicates to generate the regression equation. On the basis of the results we suggest that, for annual bluegrass and creeping bentgrass in greenhouse pot culture, this procedure can be used to accurately estimate leaf number data for remaining replicates within an experimental design, once regression coefficients are established from pooled data from two replicates.Key words: Leaf number estimation, shoot dry weight, annual bluegrass, creeping bentgrass
INFLUENCE DE LA PHOTOPÉRIODE ET DE LA TEMPÉRATURE SUR L’ÉVOLUTION DE LA TOLÉRANCE AU GEL, DE LA CROISSANCE ET DE LA TENEUR EN EAU, SUCRES, AMIDON ET PROLINE DES RAMEAUX ET DES RACINES DE GENÉVRIER (Juniperus chinensis L. ’Pfitzerana’)
Authors: BIGRAS F. J. , RIOUX J. A. , THERRIEN H. P. , PAQUIN R.
Published: March 2010

Rooted cuttings of Juniperus chinensis L. ’Pfitzerana’ were exposed to a combination of three temperatures (1, 8 and 15 °C) and two photoperiods (8 and 16 h) for 42 d in growth chambers in order to study the influence of these factors on the evolution of growth and on changes in water, sugar, starch and proline contents of stems and roots during the cold-hardening process. The acclimation process for stems is different from that of roots. At 15 and 8 °C, under a short photoperiod, stems harden, even though growth continues: water, sugars and starch levels remain constant. Therefore, the complete cessation of growth is not necessary to initiate stem hardening. At 1 °C, stem hardening is no longer influenced by photoperiod; growth is negligible, and while water content is stable sugars are accumulated. Root hardening however, is only affected by temperature. At 15 °C, we did not observe any hardening; water, sugars and starch levels remained constant while growth continued. At 8 °C the beginning of hardening was noted, water content decreased, growth slowed and, despite some fluctuations, sugar and starch did not increase. At 1 °C, growth stopped, sugars and starch were accumulated and hardening reached its maximum. Proline levels increased in stems and roots under all treatments except for stems exposed to 15 °C and a 16-h photoperiod.Key words: Juniper, frost tolerance, photoperiod, sugar, starch, proline
EFFECTS OF ’VOLUNTEER’ WHEAT AND BARLEY ON THE GROWTH AND YIELD OF RAPESEED
Authors: MARSHALL GEORGE , MORRISON IAN N. , FRIESEN LYLE , ROTHER WESLEY
Published: March 2010

Field experiments were conducted in 1982 and 1983 to determine the effects of increasing densities (0–60 plants m−2) of ’volunteer’ wheat (Triticum aestivum L. ’Neepawa’) and barley (Hordeum vulgare L. ’Bonanza’) on the growth and seed yield of rapeseed (Brassica napus L. ’Regent’). The results were plotted using linear regression analysis and described by the equation[Formula: see text]where y = biomass or yield (g m−2); b0 = intercept; b1 = linear regression coefficient and x1 = density of ’volunteer’ plants m−2. From the results obtained in 1982 and 1983, ’volunteer’ wheat interference reduced rapeseed yields as described by the equations[Formula: see text]and[Formula: see text]respectively. Similarly, the reduction in rapeseed yield in the two years caused by ’volunteer’ barley was described by the equations[Formula: see text]and[Formula: see text]Thus, an intermediate density of 30 ’volunteer’ wheat plants reduced the yield of rapeseed by approximately 17% in both years; whereas, an equivalent density of ’volunteer’ barley plants reduced rapeseed yields by approximately 27% in 1982 and 35% in 1983.Key words: Competition, rapeseed, volunteer, wheat, barley, yield loss
EPICUTICULAR WAX PRODUCTION, WATER STATUS AND LEAF TEMPERATURE IN TRITICEAE RANGE GRASSES OF CONTRASTING VISIBLE GLAUCOUSNESS
Authors: JEFFERSON P. G. , JOHNSON D. A. , ASAY K. H.
Published: March 2010

Studies were conducted to compare the effect of glaucousness on the response of perennial range grasses to drought stress. Glaucous and nonglaucous plants of an intermediate wheatgrass hybrid (Thinopyrum intermedium (Host) Barkworth and D. R. Dewey × T. intermedium-acutum D.R. Dewey pers. commun.) and an interspecific hybrid of crested wheatgrass (induced tetraploid Agropyron cristatum (L.) Gaertner s. lat. × A. desertorum (Fisch. ex Link) Schultes) were studied in field nurseries for epicuticular wax production, leaf water potential, leaf reflectance of radiation and leaf temperature. Glaucous plants of intermediate wheatgrass had higher epicuticular wax production, increased leaf reflection of radiation, lower midday canopy temperatures, and higher predawn leaf water potentials than non-glaucous plants. Similar trends were observed for the crested wheatgrass hybrids except that glaucousness did not affect midday plant temperatures. A greenhouse experiment involved comparison of glaucous and non-glaucous synthetics of Altai wild ryegrass (Leymus angustus (Trin.) Pilger Dewey). Leaves of glaucous Altai wild ryegrass reflected more radiation and used water less efficiently (total biomass basis) at high soil water content than leaves of the nonglaucous synthetic. At low soil water content, glaucous Altai wild ryegrass had higher leaf temperature and higher midday leaf water potential. Glaucous and nonglaucous Altai synthetics did not differ significantly for shoot yield, total biomass yield, and water use efficiency (shoot yield basis) at either soil water content. While glaucousness may affect water relations of these grasses, it does not necessarily affect forage yield.Key words: Water use efficiency, drought stress, leaf radiation reflectance, crested wheatgrass, intermediate wheatgrass, Altai wild ryegrass
YIELD LOSSES IN WHEAT DUE TO WEED COMMUNITIES DOMINATED BY GREEN FOXTAIL [Setaria viridis (L.) BEAUV.]: A MULTISPECIES APPROACH
Authors: HUME L.
Published: March 2010

A model was developed to predict wheat (Triticum aestivum L.) loss due to interference by multi-species weed communities dominated by green foxtail [Setaria viridis (L.) Beauv.], 3–4 wk after seeding. Results indicated that green foxtail-dominated weed communities averaging 427 plants m−2 over 4 yr reduced yield by about 7.8%. When plots were kept free of green foxtail, different species became important components of a second model developed to predict the yield loss. The combined effect of precipitation and growing degree days was an important component of both models. It is postulated that these environmental variables reflected the relative time of emergence of the weeds and the crop. Advantages of models based upon multispecies tests over those determined from one-weed one-crop tests are discussed as they relate to crop loss in multispecies situations.Key words: Setaria viridis, green foxtail, crop loss, multispecies competition, weed communities, modeling
GENETICS OF RESISTANCE TO LEAF RUST IN TWO ACCESSIONS OF COMMON WHEAT
Authors: DYCK P. L. , JEDEL P. E.
Published: March 2010

Two accessions, V336 and V618, of the A. E. Watkins wheat (Triticum aestivum) collection were studied genetically for their resistance to leaf rust (Puccinia recondita). The two accessions have in common a dominant gene that gives a fleck infection type reaction to all the isolates of leaf rust used. This gene may be a previously unidentified gene and we have tentatively assigned the gene symbol LrW. Both accessions also have gene Lr33 and V336 has LrB.Key words: Triticum aestivum, wheat, leaf rust resistance
AUGMENTATION OF FLESH CALCIUM IN APPLES BY HYDROSTATIC AND PRESSURE INFILTRATION PROCEDURES
Authors: MEHERIUK M. , MOYLS L.
Published: March 2010

Flesh calcium values in Golden Delicious and Spartan apples (Malus domestica) subjected to 50 kPa hydrostatic pressure in a 5.0-m column of 3% CaCl2 solution averaged 1000 mg kg−1 and 390 mg kg−1 (dw), respectively. Skin injury was appreciable on Golden Delicious apples but a rinse with tap water after treatment sharply reduced incidence of the injury. Fruit calcium concentrations after rinsing exceeded 250 ppm (dw), a value considered sufficient to control Ca-related disorders such as breakdown and bitter pit.Key words: Malus domestica, fruit injury, firmness, apple
IDENTITY OF A PHENOLIC EXUDATE INHIBITOR FROM GERANIUM EXPLANTS
Authors: HILDEBRANDT VIRGINIA , HARNEY PATRICIA M.
Published: March 2010

The relative amounts of phenolic exudate released from Sprinter Scarlet geranium explants were determined at time of excision and subsequently at various intervals during a 4-d period. Analysis of exudate by two-dimensional chromatography indicated that galloyl esters, gallic acid, ellagic acid, methyl gallate and an unidentified compound were present in the exudate in a 4:2:2:1:1 ratio. The exudate had an inhibitory effect on the germination of geranium seeds and on growth of geranium seedlings. Soaking explants in 0.7% PVP-AT was quite effective in adsorbing the phenolic content of the exudate but not in 0.7% PVP-40. Both forms of PVP had detrimental side effects manifested as watery, stunted shoots and, following treatment with PVP-AT, a reduced number of shoots. At concentrations of 0.25% and 0.5% AC, fewer but healthy shoots were produced from explants soaked in this adsorbent. At less than 0.10% AC, when 86% of the phenolics were adsorbed, there was no reduction in shoot number.Key words: Tissue culture, phenolic exudate, Pelargonium
ANNUAL VARIATION IN WILD RICE (Zizania palustris L.) GROWTH AND POTENTIAL YIELD IN SASKATCHEWAN
Authors: ARCHIBOLD O. W. , SUTHERLAND J. M. , GOOD A. G.
Published: March 2010

Mature wild rice plants collected from 20 sites across northern Saskatchewan over the period 1984–1987 were measured for various morphological traits. Considerable regional variation was noted for factors such as stem length, degree of tillering and seed production with plants in the west being generally more robust. Differences also occurred between years. Much of this variation appeared to be related to environmental conditions with high water levels being particularly detrimental to the plants. Seeds collected at each site during the 1986 harvest were sown into growth tanks. Plant development under uniform growing conditions was compared to individuals collected from corresponding natural sites. Although intersite variability was considerably reduced indicating a high degree of environmental plasticity in the population, some regional variation in tillering and seed production was still detectable in the artificial populations and plants from eastern sites still tended to flower earlier. Such inherent genetic variability should be considered when seed is introduced into new sites as the industry expands in northern Saskatchewan.Key words: Rice (wild), Zizania palustris L., Saskatchewan, environmental interaction, annual variation, regional plasticity
GENOTYPIC VARIABILITY IN PHYSIOLOGICAL CHARACTERS AND ITS RELATIONSHIP TO DROUGHT TOLERANCE IN DURUM WHEAT
Authors: GUMMULURU S. , JANA S. , HOBBS S. L. A.
Published: March 2010

Yield and eight other related physiological characters [photosynthetic CO2 exchange rate (CER), stomatal resistance (rs), internal CO2 concentration, water-use efficiency (WUE), chlorophyll a + b content (Chl), specific leaf weight (SLW), leaf area and shoot dry weight] were examined in 20 durum wheat (Triticum turgidum L. var. durum) genotypes grown under nonirrigated and irrigated field conditions in 1986 and 1987. Considerable genetic differences were evident for all characters under both nonirrigated and irrigated field conditions. Significant correlations between the genotype means of the 2 years and no significant genotype × irrigation interaction indicated that the genotypic rankings were generally consistent over different environments. Reduced water availability under nonirrigated conditions decreased yield, CER, shoot dry weight, leaf area, and internal CO2 concentration and increased rs. Genotypes were separated into drought-tolerant or susceptible types based on yield potential and leaf water loss. The drought-tolerant genotypes had higher WUE, Chl, yield, leaf area and shoot dry weight and lower internal CO2 concentration than the drought-susceptible genotypes. The group differences for the characters were significant only under nonirrigated field conditions.Key words: Physiological characters, drought tolerance, wheat (durum) Triticum turgidum L. var. durum
DRYING RATE AND HARVEST LOSSES OF WINDROWED VERSUS DIRECT COMBINED BARLEY
Authors: CLARKE J. M.
Published: March 2010

Windrowing of cereal crops prior to harvest is reported to hasten drying and reduce losses due to shattering compared to direct combining, but few direct comparisons have been made in barley (Hordeum vulgare L.). Field studies were conducted over 4 yr to compare drying rates and harvest losses in windrowed and standing barley cultivars with varying susceptibility to shattering. Cutting treatments for comparing harvesting losses were initiated when kernel water concentration (KWC) dropped below about 670 g water per kg kernel dry weight, and were continued for 2 wk after combine ripeness (KWC 174 g kg−1). Natural shattering losses and cutting losses were measured at each cutting time, while combine pick-up losses were determined after combining of windrows cut at KWCs greater than 174 g kg−1. Cutting and pick-up losses were independent of harvest time when KWC at cutting was greater than 174 g kg−1. Cutting loss increased after combine ripeness, but was not related to cultivar shattering susceptibility. Combine pick-up losses ranged from 0.4 to 4.3% of yield, and were greater in low-yielding crops than in high-yielding crops. Total harvesting losses for direct combining ranged from 0.1 to 2.8% of yield compared to 0.8–7.7% for windrowing prior to combining in crops harvested at or before combine ripeness. Direct combining 1 and 2 wk later caused increased harvest losses (0.3–20% of yield) which were proportional to cultivar shattering susceptibility. Windrowed barley dried to combine ripeness from 0 to 3 d (mode 1 d) faster than standing barley.Key words: Barley, shattering susceptibility, cutting loss, combine pick-up loss, harvest losses, harvest methods