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The interest in growing pulse crops and oilseeds together as intercrop combinations is increasing. However, little is known about nutrient dynamics in pulse–oilseed intercropping systems in western Canada, particularly the contributions from biological nitrogen fixation (BNF). Kabuli chickpea and brown flax were grown without added fertilizer as monocrops and as intercrops in mixed and alternate seed row configurations at sites located in the Brown (Central Butte, SK) and Black (Redvers, SK) soil zones in 2019 and 2020. Comparison was made of grain and straw yields, nitrogen (N) and phosphorus (P) uptake of grain and straw, and proportion and amount of biologically fixed N contributed from the chickpea and transferred to the flax. The intercrop grain yield land equivalent ratio (LER) and N and P uptake LER values were at or above 1 for the four site-years, indicating benefit from intercropping in increasing total yield and crop N and P uptake from the land area. The proportion of N derived from BNF was not enhanced in this intercrop combination, but considerable biologically fixed N (8%–22%) was transferred from the chickpea to the flax during the growing season. This was associated with reduced depletion of soil N compared to monocrop flax in part due to the contribution of biologically fixed N in the chickpea–flax intercrop system. [ABSTRACT FROM AUTHOR]

Liquid hog manure (LHM) and solid cattle manure (SCM) are valuable soil amendments for the nutrients and organic matter they augment. However, desire to mitigate the N2O, CO2, and CH4 fluxes attendant with their use has led to the question of whether biochar co-applied with LHM and SCM could mitigate these greenhouse gas fluxes. A split-plot design was used at two agricultural field sites with contrasting soil types (Brown Chernozem and Black Vertisol) in Saskatchewan, Canada, to assess the effect of LHM and SCM (100 kg N ha−1), alone and in combination with two different biochars applied at 8 Mg C ha−1; produced using either slow or fast pyrolysis of willow (Salix spp.) feedstock. Intact cores were collected from the plots and the N2O, CO2, and CH4 fluxes were measured during a 6-week (42 days) lab incubation. The impact of manure amendment on greenhouse gas fluxes, was more apparent with LHM than SCM; reflecting higher inorganic N content, narrower C:N, and more easily mineralizable carbon in LHM. Co-applying biochar with the manure sources reduced the manure-related N2O emissions 31.5 to 43.1% and increased CH4 consumption 94.1% to 2.1 × compared with manure alone. Regardless of soil type, neither biochar co-applied with the manures affected the net CO2 fluxes compared with manure alone. The N2O emissions were principally influenced by the impact of biochar addition on NO3-N supply and pH, while the net CO2 fluxes were controlled by the opposing effects of heterotrophic (i.e., CO2 production) and postulated autotrophic (i.e., CO2 consumption) respiration. The CH4 consumption was related to the NH4-N supply and its influence on autotrophic methanotrophy. [ABSTRACT FROM AUTHOR]

A soil test for estimating mineralizable N in soil is needed to improve fertilizer use efficiency. Our objectives were to: (i) test the effectiveness of two chemical indices in estimating potentially mineralizable N ([N.sub.0]) in soils, and (ii) determine if these indices could be used to differentiate the impact of cultural practices on the N-supplying capacity of soils. We collected samples from the 0- to 0.15-m depth of 42 soils representing all agroecological regions in Saskatchewan, Canada. We determined (i) N mineralized ([N.sub.min]), [N.sub.0], and the rate constant (k) by aerobic incubation at 35 [degrees] C for 24 wk, and (ii) the [NH.sub.4]-N extracted by (a) 2 M KCl heated at 100 [degrees] C for 4 h, and (b) a steam-distilled phosphate-borate solution buffered at pH 11.2. The association between [N.sub.0] and the hot 2 M KCl extracted [NH.sub.4]-N was close ([r.sup.2] = 0.78, significant at P < 0.001); the relationship between [N.sub.0] and the phosphate-borate [NH.sub.4]-N was slightly less precise ([r.sup.2] = 0.73, P < 0.001). When [NH.sub.4]-N extracted with cold 2 M KCl was subtracted from the [NH.sub.4]-N extracted with hot extractants, the association with [N.sub.min] was weaker ([r.sup.2] [less than or equal to] 0.50). The value of k for the 42 soils was generally constant (avg. 0.067 [+ or -] [S.sub.x]t 0.05 = 0.040 [wk.sup.-1]). In a second experiment, we compared the two chemical extractants vs. the N mineralized in a 24-wk incubation regarding their effectiveness in differentiating the effects of eight 37-yr crop rotation treatments on N-supplying capacity. These three indices performed effectively in this regard. For example, the 2 M KCl [NH.sub.4]-N was closely associated with N mineralized in 24 wk ([r.sup.2] = 0.92), as was phosphate-borate [NH.sub.4]-N ([r.sup.2] = 0.88; both significant at P < 0.001). We concluded that the chemical extractants may provide a quick test for assessing N-supplying capacity of the soil.

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil phosphorus (P) availability is commonly assumed to limit productivity in tropical soils, yet there is relatively little information on the chemical forms of soil P in such ecosystems. The study was conducted to determine the size P pools via application of gypsum. We used a sequential fractionation to assess P fractions. The average total P concentration was 519 mg kg−1. Soil organic P was relatively low (74 mg kg−1). The ratio of organic carbon to organic P was generally greater than 298, suggesting the potential for immobilization. Calcium-associated P was the dominant inorganic P pool, whereas Al+Fe-P was the second dominant. Readily available P was very low (1.3 mg kg−1). Gypsum at different level was used as a reclamation material for sodic soils, and application of gypsum significantly affected the different P fractions. Organic P forms were significantly lower for higher levels of gypsum application. [ABSTRACT FROM PUBLISHER]

Zinc and iron deficiencies affect billions of people globally and have direct impact on human health. Zinc and iron concentrations in plant materials are commonly analyzed by flame atomic absorption spectrometry (F-AAS). This research describes the optimal analysis method for precise zinc (Zn) and iron (Fe) analysis of seeds from the seven species of genus Lens. Estimation of Zn and Fe concentration in whole lentil seeds by F-AAS is destructive, using nitric acid digestion of seeds prior to instrument analysis. The procedure proposed for the determination of Zn and Fe concentration uses the minimum amount of lentil seed of all lentil species with suitable standard reference materials. The relative standard deviations of the method were about 5% for both Zn and Fe. The minimum sample amount 0.3 g of wild and 0.5 g of cultivated lentil seed samples was identified for accurate and precise estimation of Zn and Fe concentration. [ABSTRACT FROM PUBLISHER]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses whether the presence of the gene in annual canarygrass for glabrous affect the response to chloride fertilizer. The application of the chlorine increased the seed yield of annual canarygrass by 25 percent. It revealed that the mutagenic process facilitated the development of glabrouscultivars but did not affect the response of annual canarygrass to chloride fertilizer.

The article discusses a study which explored the effect of irrigation on the recovery of broadcast 15 nitrogen (N)-labelled fertilizer, applied during the final year of a three-year rotation, by willow varieties Charlie and SV1. It describes a split-split-plot experiment conducted in Saskatoon, Saskatchewan. Results showed that irrigation increased fertilizer N accumulation by Charlie, but not SV1. Irrigation also increased the N use efficiency (NUE) for both varieties' all plant tissues.

Wintering cattle directly in the field creates potential concerns with water quality, as nutrients added from urine and fecal material over the winter can end up in runoff water, ground water and soil. In 2008/2009 an experiment was conducted to observe the effect of in-field winter feeding of cows on the nutrients in spring snowmelt run-off water. Low temperatures give little opportunity for organic N, urea and ammonium added in the urine and fecal matter to convert to nitrate, resulting in nitrate- N concentrations in snowmelt run-off water that were similar in the control and winter fed areas. Orthophosphate-P and ammonium-N concentrations were significantly elevated in run-off from the winter feed treatment basins compared to the controls. Surface soil sampled in the spring from the winter feeding site had higher soluble nitrate while soluble forms of phosphorus in the soil were lower compared to the fall soil samples. Caution should be used when utilizing in-field winter feeding systems so that the runoff water does not reach sensitive water bodies. [ABSTRACT FROM AUTHOR]

Field experiments were conducted at three different sites in Saskatchewan, Canada (Colonsay, Vanscoy and Rosthern) over two years (2005 and 2006) to determine the effects of dribble-banded and coulter-injected liquid fertilizer applied in the spring of 2005 at 56, 112 and 224 kg N ha−1 with and without P at 28 kg P2O5 ha−1. The three sites were unfertilized, 7- to 8-year old stands of mainly meadow bromegrass ( Bromus riparius)-dominated haylands. All fertilization treatments produced significantly ( P ≤ 0·05) higher dry matter yield than the control in the year of application at the three Saskatchewan sites. There was no significant difference between the two application methods (surface dribble band vs. coulter injected) for any fertilizer treatments. The addition of 28 kg P2O5 ha−1 P fertilizer along with the N fertilizer did not have a significant effect on yield in most cases. In the year of application, increasing N rates above 56 kg N ha−1 did not significantly increase yield over the 56 kg N ha−1 rate in most cases, but did increase N concentration, N uptake and protein concentration. A significant residual effect was found in the high N-rate treatments in 2006, with significantly higher yield and N uptake. In 2005, the forage N and P uptake in the fertilized treatments were significantly higher than the control in all cases. The N uptake at the three Saskatchewan sites increased with increasing N rate up to the high rate of 224 kg N ha−1, although the percent recovery of applied N decreased with increasing rate. The P fertilization with 28 kg P2O5 ha−1 also increased P uptake. Overall, rates of fertilizer of approximately 56 kg N ha−1 appear to be sufficient to produce nearly maximum forage yield and protein concentration of the grass in the year of application. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) emissions from agricultural activities such as land application of livestock manure cannot be ignored when assessing overall emissions from anthropogenic sources. The magnitude of these emissions is influenced by management practices such as manure placement during land application. The objective of this work was to compare GHC fluxes resulting from the surface and subsurface application of liquid and solid manure. For this comparison, all measurements were made 24 h after application using a static chamber method. The results showed that subsurface application significantly increased carbon dioxide equivalent (CO2-e) fluxes for both solid and liquid manure. The overall CO2-e fluxes from injected treatments were 3.2 times greater than CO2-e fluxes from the surface-applied plots, mainly due to a pronounced increase in N2O fluxes, which was likely caused by increased denitrification rates. The CO2-e fluxes from liquid manure applications were also greater than the CO2-e fluxes from solid manure applications, probably due to greater levels of ammonium available for nitrification and subsequent denitrification. Methane (CH4) fluxes were negligible for all manure types and application methods 24 h after application. For this particular study, measured specific fluxes (total flux per kg N applied) remained relatively constant with application rate, indicating that GHG emissions from manure applications were approximately proportional to the amount of manure applied. [ABSTRACT FROM AUTHOR]

Soil water and nutrient availability are major limiting factors for crop production in the Canadian prairies. Most variations in soil properties observed across prairie farm fields are the result of the effect of landscape on water and soil redistribution. The relationships among soil chemical properties (pH, electrical conductivity, organic matter, and available nutrients), soil water, elevation, and canola seed yield were investigated in a transect across a hummocky, undulating farm field in the Brown soil zone of south-central Saskatchewan. Overall, seed yield was highest in foot slope positions in the landscape where soil organic matter, nutrients, and available water content were higher. Correlations between soil properties and seed yield were highest for pH (R = -0.46, P < 0.01), which was followed by organic C % (R = 0.27, P < 0.05), water content (R = 0.23), extractable potassium (K) (R = 0.18) and nitrogen (N) and phosphorus (P) supply rates to exchange resin membranes (R = 0.15). Extractable N and P were poorly correlated with seed yield (R < 0.1). The landscape region with soil parameters and yield closest to the average for the entire transect was the back slope region, suggesting that in similar landscapes, this region would be most appropriate for selection as a representative benchmark sampling site. [ABSTRACT FROM AUTHOR]

SUMMARY The systematic nature of the 34S natural abundance variations (δ34S) in a prairie and boreal forest ecosystem enabled construction of hypotheses regarding the origin and cycling of S in the two soil-plant systems. By considering the 34S abundance variations in relation to soil S transformations, a better understanding of S isotope fractionation in soils was also achieved. The δ34S values suggest that atmospheric S becomes increasingly more important as a S input as pedogenesis proceeds in these soils. The origin and movement of sulphate salt in a saline seep was evaluated using δ34S values, demonstrating the usefulness of the δ34S technique in soil salinity studies. The 34S-enrichments and depletions found in soil organic S fractions were consistent with postulated differences in lability, mobility, and turnover rate. Wheat plants growing on the saline, sulphate-saturated prairie soil were found to be enriched in 34S relative to surrounding S sources, providing indirect evidence for release of 34S-depleted H2S by the plants as a S-stress relief mechanism. [ABSTRACT FROM AUTHOR]

We examined soil potassium (K) supply capacity as related to wheat response to K fertilization, using a cation exchange membrane (CEM) burial technique to measure potential K supply rate. A growth chamber experiment was conducted to determine soil and plant response relationships. Canadian Prairie Spring wheat (Triticum aestivum ’Biggar') was grown on three soils of different initial K fertility with three rates of added K. Wheat response to K fertilization was well related to the amount of exchangeable K and K supply rate in the soil. Soils with high initial K supply rate demonstrated an adequate K release rate which was associated with low response to added K fertilizer. A soil K supply rate less than 5 μg cm2 hr‐1 represented soil K supply power that is less than optimal for wheat nutrition. [ABSTRACT FROM PUBLISHER]

In a southern boreal aspen forest located in Saskatchewan, Canada, we examined decomposition rates of leaf litter from trembling aspen (Populus tremuloides Michx.), hazel (Corylus cornuta March.), and a mixture of different species over a six‐month period. Mass loss was measured in the field using the litter bag method. The greatest mass losses occurred during the first month regardless of litter type. On average, mass loss during the first 28 days was 3.2 g#lbkg‐1#lbd‐1 for the aspen leaves, 4.4 for hazel leaves and 4.9 for the mixture. The initial rapid loss of weight is attributed to leaching and decomposition of water soluble material. The decomposition rates of the leaf litter were related to water‐soluble organic carbon and nitrogen content, and C:N ratio. Several models were used to describe mass loss of the aspen, hazel, and mixed leaf litter at the early stages of decomposition. A single model was not found to be appropriate to describe decomposition of all leaf‐litter types. A second order model provided the best fit for the aspen litter decomposition, while the logarithmic model best described the decomposition of hazel and mixed leaf litter. [ABSTRACT FROM PUBLISHER]

Two simple methods to extract potassium (K) from fresh plant tissues for use as possible quick K tests: i) freeze/squeeze in which the tissue is frozen, thawed and extracted by placement in a syringe, and ii) press in which the sap is extracted by crushing fresh leaves in a garlic press, were evaluated. The K concentration in the leaf sap extracted using the two methods was determined using a hand‐held ion selective electrode meter. Two separate growth chamber experiments were conducted to evaluate method performance. In the first experiment, the relationships of fresh leaf sap K with total plant K and with K availability in the soil were determined using canola (Brassica campestris var. Profit) and wheat (Triticium aestivum var. Biggar). In the second experiment, canola (Brassica campestris var. Profit), chickpea (Cicer arientinum), and dwarf sunflower (Helianthus) were grown on two soils low in available K with six rates of added K. The fresh leaf K extracted by the two methods and measured using portable ion selective electrode were well correlated with total plant K concentration at harvest, and also closely reflected the differences in K availability in the soil as indicated by soil extraction and rates of added K. Among the two methods, the press method using a hand‐held squeezing device is the simplest one. However, the freeze/ squeeze method may be a more suitable predictor of the K availability in plant tissue that is less succulent. [ABSTRACT FROM PUBLISHER]

Land application of manure constitutes an effective means of recycling manure nutrients to the soil. However, odours from manure application activities can hinder the expansion of the livestock industry because of the potential nuisance to neighbours. The objective of this study was to assess the efficiency of subsurface application at reducing odours from both solid and liquid manure applications. Flux chambers and dynamic dilution olfactometry were used to assess odours from two manure types (solid and liquid) applied at four application rates using surface and subsurface application methods. The results of the study indicated that odour concentrations from subsurface application plots were up to 66% (37% on average) lower than concentrations from plots where the manure was surface applied. Subsurface application seemed to have a larger impact on reducing odours from solid manure than liquid manure, mainly due to better manure coverage after subsurface application of solid manure. Odours from solid manure applications measured immediately after application were also 37% lower than from liquid manure applications. In general, odours from liquid and solid manure increased with higher application rates, but there was little difference among the low, mid, and high application rates. Based on the results of this study, subsurface application of manure is an effective way to reduce the overall odour emissions from manure spreading, particularly for solid manure. [ABSTRACT FROM AUTHOR]