Browsing by Author "Walley, F.L."
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Item Assessing microbial communities in transplanted soils after 21 years(2013-03-05) Katulanda, P.; Walley, F.L.; Helgason, B.L.Item Developing precision farming management strategies(1998-02-19) Pennock, D.J.; Walley, F.L.; Solohub, M.Item Does crop residue N influence soil N availability?(1998-02-19) Fu, G.; Walley, F.L.; van Kessel, C.A landscape study was conducted near Biggar, Saskatchewan, to study the influence of crop residues on the availability of soil N in the second phase of crop rotations. In order to compare leguminous and cereal residues, chickpea (Cicer arierinum) and wheat (Triricum aestivm) residue were used. The results showed that plant N derived from soil (Ndfs), added nitrogen interaction (ANI) and N recovery from chickpea residue were higher than from wheat residue in footslopes, but not in the shoulders. Chickpea residue increased soil N availability and crop production, whereas wheat residue decreased crop production in the footslopes, but there was no difference between these two residues in the shoulders, indicating that the impact of crop residues was variable and dependent on landscape position.Item Dry bean production: effectiveness of inoculants and N fertilizer(2000-02-22) Nleya, T.M.; McAndrew, D.; Walley, F.L.; Vandenberg, A.Dry bean (Phaseolus vulgaris) production in western Canada is steadily increasing. In 1999 production reached 200 000 acres in Manitoba and 12 000 acres in Saskatchewan. These figures are projected to increase to 270 000 acres and 22 000 acres in Manitoba and Saskatchewan respectively by the year 2000. Thus, the crop is now an important component of the pulse industry in western Canada. With this expansion, producers are raising concerns and questions about nutrient management in dry bean production. Most of the concerns are centered on use of Rhizobium inoculants and N fertilizers. Considerable effort has gone into investigating the effectiveness of Rhizobium inoculants for bean production. Some of the experiments have looked at the effect of different inoculum formulations on the nodulation and nitrogen fixation. Other studies have investigated different inoculant placement methods while others have compared Rhizobium inoculants with N fertilizer. This paper reviews findings from these experiments and suggests future research topics.Item Effect of available soil N on growth, yield and N, fixation by common bean(1997-02-20) de Silva, N.K.D.C.; Slinkard, A.E.; Walley, F.L.Two common bean cultivars were grown in a low nitrogen (N), stubble field with and without Rhizobium inoculation. Four rates of nitrogen fertilizer were applied. In addition, double enriched ammonium nitrate (10% atom excess) was used in microplots to estimate percentage nitrogen derived from the atmosphere (%Ndfa). Increased rates of N fertilizer resulted in increased plant height and yield and decreased %Ndfa. Inoculation of bean with granular Rhizobium inoculant enhanced N, fixation and improved seed yield.Item Effect of fungicide seed treatment on rhizobial survival and nodulation of chickpea(1999-02-25) Kyei-Boahen, S.; Walley, F.L.; Slinkard, A.E.Chickpea seeds are often treated with fungicides to prevent losses due to seed-borne pathogens and damping off. In addition, rhizobia are applied to the seeds to ensure effective nodulation and subsequent nitrogen fixation. Although reports are conflicting, several studies have conclusively shown that some of these chemicals are incompatible with Rhizobium. Furthermore, it was demonstrated that different species and strains of the same species of Rhizobium differed in their sensitivity toward various fungicides. Therefore, the objectives of this study were to examine the effect of four commercial fungicides, Apron, Thiram (Arrest 75W®), Crown and Captan on 1) the survival of Rhizobium ciceri strain BCF 32 inoculated onto chickpea seeds and 2) nodulation, nitrogen fixation and dry matter production of chickpea in the growth chamber.Item Effect of inoculum placement on chickpea inoculation(1998-02-19) Kyei-Boahen, S.; Walley, F.L.; Slinkard, A.E.Item Grain yield response to N fertilizer across landscape positions(1998-02-19) Solohub, M.P.; Pennock, D.J.; Walley, F.L.Item Growth and nitrogen fixation of field pea and lentil as influenced by herbicides: a three year field study(1988-02-19) Germida, J.J.; Slinkard, A.E.; Nelson, L.M.; McKercher, R.; Walley, F.L.A three-year field study was conducted in the Dark Brown and Black Soil Zones of Saskatchewan to assess the effects of trifluralin (Treflan ), metribuzin (Sencor), MCPB (Tropotox), and sethoxydim (Poast) on growth and symbiotic nitrogen fixation of field pea (Pisum sativum cv. Trapper) and lentil (Lens culinaris cv. Eston). Herbicides were applied at Saskatchewan recommended field rates and twice the recommended field rates. Treflan, Sencor, and Poast did not adversely affect plant growth or nitrogen fixation potential of field pea and lentil when applied at recommended field rates. Similarly, application of MCPB at the recommended rate did not adversely affect field pea under normal growing conditions. In some instances, herbicide application at the recommended rate was observed to have a stimulatory effect on growth and nitrogen fixation. In contrast, at application rates in excess of those currently recommended in Saskatchewan, or when plants were severely stressed by unfavorable growing conditions such as poor soil moisture, plant growth, yield, nodulation, and nitrogen fixation were adversely effected by herbicides. These effects were not consistent nor were they predictable. MCPB is not registered for use in lentil and, when applied in this crop, often resulted in reduced nitrogen fixation and seed yield. In all cases, data suggest that reductions in the nitrogen fixation potential were due to indirect effects of herbicide application on plant growth rather than to direct effects on nodulation and nitrogenase activity.Item Impact of in-crop and soil residual herbicides on effective nitrogen fixation in field pea (Pisum sativum L.) and chickpea (Cicer arietinum L.)(2006-03-02) Taylor, A.; Walley, F.L.; Holm, R.; Sapsford, K.; Lupwayi, N.A three-year project was initiated in 2004 to examine the effects of residual herbicides and registered “in-crop” herbicides, both soil and foliar applied, on N fixation and consequent yield of field peas and chickpeas. Inoculation strategies were examined to determine if inoculant formulation (i.e., peat powder versus granular inoculant) influences the degree to which herbicides can affect N fixation. This research is ongoing and thus all results are considered preliminary. Preliminary results in field pea, suggest that where herbicides had a negative effect on N fixation, the effects occurred at relatively early growth stages (i.e., soon after herbicide application) and were typically overcome at later growth stages. In addition, granular inoculants were associated with increased N fixation as compared to peat powder inoculants, and may have mitigated any negative herbicide effects. Chickpea incurred damage from the herbicides and all treatments had significantly less N fixation than the control. In general, results suggest that N fixation may be compromised if herbicides cause significant plant damage; however, improved weed control associated with herbicide application may counter the negative impact on early N fixation.Item Impact of nitrogen source, anhydrous ammonia rate, opener type, and landscape position on grain yield and grain protein of spring wheat(1998-02-19) Matus, A.; Hnatowich, G.; Walley, F.L.; Farrell, R.E.; van Kessel, C.; Knight, J.D.Item The influence of long-term crop rotations on vesicular-arbuscular mycorrhizae infection of spring wheat(1991-02-21) Walley, F.L.; Germida, J.J.Vesicular-arbuscular mycorrhizae (VAM) play an important role in the nutrition of many agriculturally important crops. Because of the ubiquitous nature of the mycorrhizal association and the important role that VAM play in crop nutrition and growth, factors affecting this beneficial association need to be identified. Field studies were conducted to monitor the influence of long-term crop rotations on VAM infection of spring wheat. Wheat root samples were collected at regular intervals from Agriculture Canada long-term rotation studies located at Swift Current, Indian Head, Scott and Melfort, Saskatchewan. Root segments were stained, and percent infection was determined by microscopic observation. VAM infection was favoured by continuous wheat rotations at all but one location. The exception existed in the Brown Soil Zone were V AM infection was reduced in the continuous rotation. Likewise, the inclusion of summerfallow in the rotation sequence reduced VAM infection. Phosphorous application generally reduced levels of VAM infection. Factors influencing the VAM association included length of rotation and fertilizer application history.Item Influence of seeding rate and KCl application across the landscape(1998-02-19) Johnston, A.M.; Hnatowich, G.L.; Hogg, T.; McConkey, B.G.; Pennock, D.J.; Walley, F.L.The development of variable rate controllers for air seeder carts has provided farmers with the opportunity to consider varying the rate of fertilizer and seed at seeding. While considerable work has been completed, or is currently under way, evaluating variable fertilizer rates, little has been done to determine the effect of varying seeding rates. In addition, application of potassium chloride across the landscape has been found to provide variable grain yield responses for CWRS wheat. Field research trials were established in 1997 at St. Louis (Black soil zone) and Watrous (Dark Brown soil zone) to evaluate the effect of varying CWRS wheat seeding rate and KC1 application across the upper, mid and lower slope positions of a hilly landscape. While increasing seeding rate resulted in an increase in plant establishment, this was not reflected in final grain yield. Yield component analysis determined that the increase in grain filled heads at harvest with increased seeding rate was offset by a reduction in the number of kernels per head. Wheat response to KC1 was highly variable, with an increase in grain yield at St. Louis and a decrease at Watrous. While July growing season conditions were dry at both Watrous and St. Louis, we did not collect sufficient crop establishment and yield component data to explain the results obtained.Item Landscape- and micro-scale variability of nitrogen fixation by chickpea(1997-02-20) Fu, G.; Walley, F.L.; van Kessel, C.A landscape-scale study was conducted near Biggar, SK, to estimate N2 fixation by chickpea (Cicer arietinum) using the natural 15N abundance method. The spatial variability of N2 fixation was investigated at both the landscape- and micro-scale. Percentage of N derived from atmosphere (%Ndfa) in chickpea seed and residue ranged from 41.1%-69.5 % and 31.9%-88.4% , respectively. Total kg Ndfa (residue plus seed) was estimated as 8.2-83.8 kg N ha-t. Soil moisture, mineral N and pH were characterized by a distinct spatial pattern. Symbiotic N2 fixation, however, was not associated with a regular spatial pattern. Soil properties and N2 fixation were poorly correlated. Symbiotic N2 fixation was highly variable at both the landscape- and micro-scale.Item Microbial community structure in long-term no-till and intensive-till soils(2009-02-25) Helgason, B.L.; Walley, F.L.; Germida, J.J.Conversion from intensive tillage (IT) to no-till (NT) management creates an altered habitat for soil microorganisms. We utilized four long-term tillage experiments in Saskatchewan and Alberta to compare NT and IT microbial communities. Microbial abundance increased at the soil surface (0- to 5-cm depth) in NT vs. IT soils. Differences were much less pronounced or negligible at the 5- to 10-cm and 10- to 15-cm depths. Despite increased biomass of fungi and bacteria in NT surface soils no significant shift in the relative proportion of individual groups of organisms within the community was observed. Similarly, analysis of bacterial DNA fingerprints indicated that while microbial community clusters in the 0- to 5-cm depth increment were different than those at greater depth, there was no significant effect of tillage. Our results demonstrate that depth was a stronger determinant of microbial community structure than tillage management.Item Mineral nitrogen variability across and within landscape positions(1999-02-25) Solohub, M.P.; Pennock, D.J.; Walley, F.L.Item Mobility of copper fertilizers in soils(2002-02-20) Flaten, P.L.; Walley, F.L.; Karamanos, R.E.Due to its cationic nature, Cu mobility is assumed to be very limited in Prairie soils, which are dominated by negatively charged constituents (McLaren et al., 1983). Clay and organic matter are major sources of these negatively charged surfaces. Root interception, therefore, plays an important role in plant uptake of Cu. Normally, where Cu fertilizer applications are required to correct a deficiency, proximity to growing roots is considered essential (Gilkes and Sadleir, 1979). Incorporation of surface broadcast copper sulphate (CuSO4) has been an effective practice. However, over the past decade, there has been a significant shift towards less tillage and an increased awareness of other products and methods of application. Chelating agents are added to nutrient solutions to increase the solubility of metal cations. Metal chelates are characterized by the formation of more than one bond between the metal and functional groups of the complexing agent, forming a ring structure incorporating the metal ion. One of the most common chelating agents used for this application is EDTA (ethylene diamine triacetic acid). The relatively high stability of this product in chemical reactions is seen as an advantage for maintaining the availability of the nutrient. The objective of this experiment was to identify the relative mobility of Cu, using two fertilizer products, namely, CuSO4 (salt) and Cu-EDTA (chelate).Item Optimizing productivity in organic farming systems through variation of seeding density for field peas and lentils(2006-03-02) Baird, J.M.; Walley, F.L.; Shirtliffe, S.J.Item Precision farming in Saskatchewan: to pursue or not to pursue, that is the question(1995-02-23) van Kessel, C.; Walley, F.L.Item Response of chickpea to nitrogen and phosphorus fertilization(1998-02-19) Walley, F.L.; Hnatowich, G.A field study conducted in 1996 at four locations on soils with relatively low levels of available N and/or to investigate the N and P fertility requirements of desi- and kabuli-type chickpea. The treatments included four levels of “starter N” (46-O-O at 0, 15, 30, and 45 kg N ha-l) and 3 levels of seed-placed P205 (11-54-o at 0,20, and 40 kg P205 ha-l). Regular monitoring of the plots indicated that although growth stages during active plant growth (i.e., days to flowering, pod formation, etc.) were largely unaffected by fertilizer application, seed maturity was, in some instances, extended as a consequence of fertilizer application. Estimates of symbiotic N2 fixation suggest that increasing increments of fertilizer N resulted in concomitant reductions in symbiotic N2 fixation by kabuli-type chickpea whereas symbiotic NZ fixation by desi-type chickpea was less sensitive to inorganic N. Application of “starter N” and seed-placed P205 did not confer a predictable seed yield advantage to either desi- or kabuli-type chickpea. Because results of the 1996 field season indicated few, if any, yield responses to seed-placed N and P, the field design was modified in 1997 to accommodate side-band applications of PI05 fertilizer. As was observed in 1996, application of starter N reduced NZ fixation and did not result in a significant seed yield advantage. Moreover, in 1997, application of P205 did not confer a consistent seed yield advantage at all sites. Similarly, the influence of P205 placement on seed yield was not consistent.