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Previous studies with chromosome substitution lines between hard red winter wheat (Triticum aestivum L.) cultivars Cheyenne (CNN} and Wichita (WI) identified genes on chromosome 3A of WI which affect grain yield, yield components, grain volume weight, plant height, and anthesis date. This study was conducted to determine if the trait variation caused by chromosome 3A could be explained by major or minor gene segregation and if these genes are pleiotropic, linked, or independent on the chromosome. A population of recombinant inbred chromosome lines for chromosome 3A (RICLs-3A), developed between CNN and a chromosome substitution line CNN(WI3A), was evaluated in multi-location field trials in 3 yr. Our results indicate significant differences (P [is less than or equal to] 0.05) between parental lines and among RICLs for grain yield, 1000-kernel weight, plant height, and anthesis date, but not for kernel number per spike, spike number per square meter, and grain volume weight. A 1:1 genetic ratio for anthesis date suggested the presence of a single segregating locus controlling the trait. None of the other agronomic traits could be separated into unequivocal groups and hence, major genes were not detected. This indicates that the traits were controlled either by several genes or few genes with enough environmental influence, or both, to obscure their effects. Significant correlations and possible crossover products between anthesis date, plant height, and 1000-kernel weight suggest that these traits were controlled either by linked gene(s} or by pleiotropic genes with additional genes affecting one of the traits., PREVIOUS RESEARCH with reciprocal chromosome substitution lines between bread wheat cultivars Cheyenne (CNN) and Wichita (WI) determined that WI chromosome 3A contained gene(s) that significantly increased grain yield and 1000-kernel [...]

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ABSTRACT: Being a waste material, fly ash can be used in large quantities in construction of highway and railway embankments. This paper presents a series of plane strain model tests carried out on both reinforced and unreinforced fly ash embankment slopes. Laboratory tests were conducted by varying parameters such as embedment ratio, length and number of reinforcement layers, and edge distance from slope crest. A numerical study using finite-element analysis (PLAXIS 2D, version 9.0) was also carried out to verify the model test results. The size of the numerical model was kept the same as that of the laboratory test model. The agreement between observed and computed results was found to be reasonably good. Based on numerical and experimental results, the critical values of the geogrid parameters for maximum reinforcing effects were established. [ABSTRACT FROM AUTHOR]

Six field experiments were conducted on sulfur-(S) deficient Gray Luvisol (Typic Cryoboralf) and Dark Gray Chernozem (Typic Cryoborolls) soils at various locations in Alberta and Saskatchewan to evaluate the effectiveness of elemental S (ES-90, ES-95, Urea S, Fine S Powder), sulfate-S (ammonium sulfate, sodium sulfate), and elemental S + sulfate-S (Sulgro-68, Agrium Plus) fertilizers, and their rates and placement methods on seed yield and S uptake of canola and barley, and forage dry matter yield of pure bromegrass and bromegrass-alfalfa mixed stands. There was a substantial increase in yield and/or S uptake from sulfate-S application in most experiments. This indicated that the soils used in these experiments were deficient in plant-available S, especially for canola. In the initial year, the performance of elemental S fertilizers was usually inferior to sulfate-S fertilizers. Among the elemental S fertilizers, the ES-95 tended to produce greater yield and S uptake than ES-90. In general, there was no difference in seed yield between early (May 1) and late (May 23) spring applications for the elemental S (Urea S). The results indicated that from the second or third year of initiating annual applications the effectiveness of some elemental S fertilizers almost approached the level of sulfate-S fertilizers. Residual effect of S application lasted for at least three years. Overall, the findings suggest that correction of a severe S deficiency by elemental S alone may be risky in the short term, and thus addition of some sulfate-S in the initial 1 or 2 years to supplement the sulfate-S from elemental S is advisable. Increased exposure of elemental S fertilizers to oxidation either by incorporation and broadcast methods or by application ahead of plant use time tends to improve crop response. [ABSTRACT FROM AUTHOR]

Previous studies with chromosome substitution and recombinant inbred chromosome lines identified that chromosome 3A of wheat cv. Wichita contains alleles that influence grain yield, yield components and agronomic performance traits relative to alleles on chromosome 3A of Cheyenne, a cultivar believed to be the founder parent of many Nebraska developed cultivars. This study was carried out to examine the genetic similarity among wheat cultivars based on the variation in chromosome 3A. Forty-eight cultivars, two promising lines and four substitution lines (in duplicate) were included in the study. Thirty-six chromosome 3A-specific and 12 group-3 barley simple sequence repeat (SSR) primer pairs were used. A total of 106 polymorphic bands were scored. Transferability of barley microsatellite markers to wheat was 73%. The coefficient of genetic distance (D) among the genotypes ranged from 0.40 to 0.91 and averagedD=0.66. Cluster analysis by the unweighted pair-group method with arithmetic averages showed one large and one small cluster with eight minor clusters in the large cluster. Several known pedigree relationships largely corresponded with the results of SSR clusters and principal coordinate analysis. Cluster analysis was also carried out by using 22 alleles that separate Wichita 3A from Cheyenne 3A, and three clusters were identified (a small cluster related to Cheyenne of mainly western Nebraska wheat cultivars; a larger, intermediate cluster with many modern Nebraska wheat cultivars; a large cluster related to Wichita with many modern high-yielding or Kansas wheat cultivars). Using three SSR markers that identify known agronomically important quantitative trait loci (QTL) regions, we again separated the cultivars into three main clusters that were related to Cheyenne or Wichita, or had a different 3A lineage. These results suggest that SSR markers linked to agronomically important QTLs are a valuable asset for estimating both genetic similarity for chromosome 3A and how the chromosome has been used in cultivar improvement. [ABSTRACT FROM AUTHOR]

Information on the long-term impact of repeated annual fertilizer applications of different nitrogen (N) sources on soil and plants is needed to develop sustainable grassland production systems. The concentration of macronutrients in the 0-5, 5-10, 10-15, 15-30, 30-60, 60-90 and 90-120 cm layers in a thin Black Chernozemic (Typic Boroll) soil and in bromegrass (Bromus inermis Leyss.) hay were compared after 15 annual applications of 168 and 336 kg N ha-1 as ammonium nitrate, urea, calcium nitrate, and ammonium sulphate, and a zero-N check. The concentration of NO3-N was increased by ammonium nitrate and ammonium sulphate at both N rates in most soil layers, by calcium nitrate at both N rates and by urea at 336 kg N ha-1 in the 1560 cm soil. The accumulation of NO3-N increased with soil depth down to 60 cm, except for urea and ammonium sulphate at 168 kg N ha-1, and then it declined in deeper soil layers. The concentration of NH4-N was increased with fertilizer applications in some of the surface soil layers. The concentration of P was increased in the top 15 cm soil by ammonium nitrate and ammonium sulphate. The concentrations of Ca, Mg and K in the surface soil declined with most of the N fertilizer treatments while some treatments increased the Ca and Mg concentrations in the deeper soil layers. Increasing the N rate from 168 to 336 kg N ha-1 usually accentuated the above stated N effects on the concentration of macronutrients in the soil. The nitrate-based fertilizers caused more accumulation of NO3-N in some soil layers than the ammonium-based fertilizers. The relative increase in the concentration of NH4-N and P and the decline in the concentration of Ca, Mg and K in the soil by N addition was usually associated with the concomitant lowering of soil pH by N fertilization. In bromegrass hay, the total N concentration was increased by N fertilization but the concentration of other elements, except K, usually declined because of the dilution effect of the extra hay yield associated with N addition. Increasing the N rate from 168 to 336 kg N ha-1 further elevated the total N concentration but had no effect on the concentration of the other elements. Total N concentration in the hay tended to be greater with ammonium sulphate and ammonium nitrate than with the other 2 fertilizers. The concentration of total S was greater with ammonium sulphate than the other N fertilizers, and the concentration of P, Ca, Mg and K was not affected by the N fertilizer type. Fertilizer-induced high levels of NO3-N, NH4-N and P in soil may present potential for environmental pollution at these high N rates. [ABSTRACT FROM AUTHOR]

Genotype × environment interactions (GEI) and quantitative trait loci × environment interactions (QEI) are known to influence the expression of agronomic performance traits in wheat. The aim of this study was to provide biological and environmental explanations for large GEI and QEI known to affect the expression of genes on chromosome 3A of wheat (Triticum aestirum L.). Agronomic performance and molecular marker data available for a population of chromosome 3A recombinant inbred chromosome lines (RICLs-3A) in seven environments was used along with environmental covariate data to construct individual factorial regressions to explain GEI and QEI. Precipitation and temperature before anthesis had the greatest influence on agronomic performance traits for the RICLs-3A, and explained a sizeable portion of the total GEI for those traits. Individual molecular marker × environmental covariate interactions explained a large portion of the total marker x environment interactions for several agronomic traits. Seventy-six percent of the QEI for a major grain yield quantitative trait locus (QTL) was explained by the effect of temperature during preanthesis growth on dissimilar QTL genotype differentials across testing environments. Environmental covariates provided a strong basis for explaining QEI using marker × environmental covariate interactions. [ABSTRACT FROM AUTHOR]

Cropping systems can influence the accumulation and distribution of plant nutrients in the soil profile, which can affect their utilization efficiency by crops and pollution potential in the environment. A field experiment was conducted on a Dark Brown loam soil at Scott, Saskatchewan, Canada to assess the effects of input level, cropping diversity and crop phase on the accumulation and distribution of nitrate–nitrogen (N) and extractable phosphorus (P) in the soil profile at the end of 1995 to 2000 growing seasons. The 54 treatments were combinations of three input levels (organic—ORG, reduced—RED and high—HIGH), three cropping diversities (low diversity—LOW, diversified annual grains—DAG, and diversified annual and perennials—DAP), and six crop phases chosen from fallow (tillage-fallow or chem-fallow), green manure [lentil—Lens culinaris Medicus or sweet clover—Melilotus officinalis (L.) Lam], spring wheat (Triticum aestivum L.), canola (Brassica napus L. and Brassica rapa L.), fall rye (Secale cereale L.), field pea (Pisum sativum L.), spring barley (Hordeum vulgare L.), flax (Linum usitatissimum L.), oats (Avena sativa L.), and bromegrass (Bromus inermis Leyss), alfalfa (Medicago sativa Leyss) mixture hay. Soil was sampled from the 0–15, 15–30, 30–60, and 60–90 cm depths in each crop phase from 1995 to 2000, with additional depths 90–120, 120–150, 150–180, 180–210, and 210–240 cm taken from the wheat phase in 2000. In general, there were greater amounts of nitrate–N with HIGH input compared to ORG or RED inputs, especially under LOW diversity. The nitrate–N in various soil depths suggested some downward movement of nitrate–N to the deeper soil depths when HIGH input was compared to ORG input. In LOW cropping diversity, green manure or fallow usually had more nitrate–N in soil than other crop phases. In DAG... [ABSTRACT FROM AUTHOR]

Nitrogen fertilization is essential to produce high forage yields in the Canadian prairies but its long-term use have been observed to alter the chemical soil properties and composition of forage. Lime application is used to ameliorate soil acidity and create favorable soil conditions for sustainable crop production. We studied the effects of 27 annual applications (1968 to 1994) of 0, 56, 112, 168, 224 and 336 kg N ha[sup -1] and one surface application of lime in 1991 (finely-ground CaCO[sub 3] to bring pH of surface 15 cm soil close to 7.0) at Crossfield, Alberta, Canada. We measured the concentration of macroelements in the 0-5, 5-10, 10-15 and 15-30 cm layers of a thin Black Chernozemic (Typic Boroll) soil and smooth bromegrass (Bromus inermis Leyss) hay in 1994. The concentration of NO[sub 3]-N in soil increased linearly with N rate in all layers and it also increased with soil depth. The concentration of NH[sub 4]-N increased markedly with N rate in the 0-5 and 5-10 cm layers, and its response to the N rate was linear for the 0-5 cm and quadratic for the deeper layers. The concentration of extractable P in the soil decreased at low N rates and then usually increased at higher N rates. The concentrations of extractable Ca, Mg, K and Na in the surface soil layers declined with increasing N rates in most cases, while their concentrations in deeper soil layers declined with higher N rates after initially increasing at lower N rates. The concentration of extractable Ca indicated that the downward movement of lime was restricted mainly to the 0-5 cm soil layer. Liming usually reduced the concentrations of NO[sub 3]-N, P, NH[sub 4]-N, Mg, K and Na in some of the shallow soil layers, but it tended to increase NO[sub 3]-N, Mg and Na concentrations in some deeper soil layers and increased Ca concentration in shallow soil layers. In bromegrass hay, total N concentration increased and the concentrations of total P, S, Ca, Mg and K tended to decline with increasing N... [ABSTRACT FROM AUTHOR]

Evaluates the effects of fertilizer N and P rates, application times and placement methods on root mass of meadow bromegrasses, alfalfa and barley in the soil of Central Canada. Application time, source and placement of N effects on bromegrass root mass; P rate effects on smooth bromegrass root mass; Use of the fertilizers to increase root mass and increase carbon storage in soil.

A field experiment was conducted from 1993 to 1995 on a phosphorus (P)-deficient Black Chernozemic (Typic Boroll) soil near Ponoka, Alberta, Canada to compare the effectiveness of broadcasting (spread on the soil surface) versus banding (1.5 cm wide band placed 5 cm deep and 15 cm apart, using a coulter-type disc drill) of P fertilizer applied annually (10, 20, 30, and 40 kg P ha-1) or at time of forage establishment (50, 100, 150, and 200 kg P ha-1) on dry matter yield (DMY), protein yield (PY) and P uptake (PU) of bromegrass (Bromus inermis Leyss) managed as hay. Fertilizer P markedly increased DMY, PY, and PU in all the three years. Annual broadcasting of P fertilizer produced greater increase in DMY, PY, and PU than banding (by 921 kg DMY ha-1, 71 kg PY ha-1, and 1.51 kg PU ha-1). On the contrary, banding P fertilizer at establishment produced higher increases in DMY, PY, and PU than broadcasting (by 3136 kg DMY ha-1, 331 kg PY ha-1, and 7.42 kg PU ha-1). The differences in DMY, PY, and PU between banding and broadcasting were not influenced by P rate. The increase in DMY, PY, and PU tended to increase with P rate, except for the establishment-time broadcasting treatments. Broadcast P fertilizer was much more effective with annual than establishment time application, whereas banded P fertilizer was almost equally effective with establishment-time and annual applications. Overall, annual broadcasting was most effective, establishment-time broadcasting was least effective and effectiveness of annual or establishment-time banding was intermediate. [ABSTRACT FROM AUTHOR]

Discusses the development of a genetic linkage map and identifies molecular markers associated with the Eps locus and with quantitative trait loci controlling agronomic traits on chromosome 3A of wheat. Use of recombinant inbred chromosome line to identify and map genes; Limited factors for detecting QTL for grain yield.