Stubble height and fertilizer N requirements for maximizing canola yield in the semiarid Canadian prairie

Non-Peer ReviewedCanola is becoming a viable crop when grown under fallow in the semiarid prairie, but is also grown in longer rotations, most often direct seeded into standing stubble. Taller standing stubble provides the canola seedlings with a more favorable micro-climate promoting more efficient use of water and increased yields compared to canola grown without the protection of standing stubble. When grown under the more limited moisture conditions of extended rotations but in the moisture conserving characteristics of taller standing stubble, we found canola yielded best with fertilizer N rates similar to those of the moister Black soil zone. Canola yields were consistently highest when fertilized with > 100 kg N ha-1

Canola yield formation under different population and water use levels

Non-Peer ReviewedOptimum population is the foundation for high yields under rain-fed agriculture and the optimum population depends on the water availability. However, establishing a good canola stand in the Canadian semiarid Prairie, where low temperature, water stress and soil crusting result in poor seed bed conditions, is difficult. A field study was conducted during 2000, a year with moderate soil moisture and good canola growing conditions, and 2001, a year with severe water and heat stress, to understand the plasticity of canola yield parameters at different (80 to 5 plants per square meter) plant populations. The primary response of canola to lower plant population was increased branching, although it did not compensate completely for the decreasing population. Increased branching was accompanied by increased production and increased distribution of pods on the primary and secondary branches. Canola exhibited plasticity in yield adjustment over a wide range of plant populations. Environmental conditions played a significant role in expressing canola plasticity. For example, in a normal year like 2000 canola maintained similar yield levels over a wider range of populations (80 to 20 pl m-2), while in a dry year like 2001 seed yield started declining with populations below 40 pl m-2. Ability to produce more pods, especially at lower population densities, was responsible for the environmental influence on yield formation

Analyzing color infrared aerial photographs for the delineation of management units in site-specific agricultural management

Non-Peer ReviewedThis poster addresses the potential of a color infrared aerial photograph to provide spatially distributed information for site specific management. In this process digitized color infrared aerial photographs were used to extract vegetation index information. Crop and soil information were obtained through field sampling. Most important factors for affecting crop productivity were determined using principal component analysis. Point information were interpolated using kriging to create grid surface of the study area. Centroid of each grid cell was used to collect crop and soil information, and vegetation index at a regular interval throughout the study area. Fuzzy k-means with extra-grades algorithms were used to delineate potential within-field management units based on soil and crop information and vegetation index separately. Within-zone grain yield variation were calculated and used to evaluate management zones. The methodology is fast, can be easily automated in commercially available GIS software and has considerable advantages when comparing to other methods for delineating within-field management zones

The effect of pulse crop rotation and controlled-release urea on the N accumulation and end-use quality of CWRS wheat

Non-Peer ReviewedSpring wheat was grown at Carman in 2000 and 2001, and at Brandon, MB, in 2001, on field pea and flax stubble at three rates of N (0, 30, and 90 kg N ha-1) supplied as ammonium nitrate (AN) or controlled release urea (CRU), a polyurethane-coated urea. Wheat was grown in 2000 and 2001 at Swift Current, SK, on field pea and durum stubble at three rates of urea N (34, 50, and 78 kg N ha-1) based on soil test recommendations. Wheat grown on field pea stubble (P-W) had higher protein content (PC) than wheat grown on flax/durum stubble (F-W) at four of the five sites evaluated. Contrary to expectations, post-anthesis apparent net mineralized N and proportion of total N uptake were higher for F-W compared to P-W at the Carman 2000 and Brandon 2001 sites. Differences between fertilizer N sources were minor. Breadmaking quality of the wheat end-use quality was also assessed. At the same flour protein content (FPC), P-W had a shorter Mixograph dough development time, work input-to-peak, dough strength index, and breakdown resistance, and also tended to be more extensible than F-W

Chickpea, field pea, and lentil yields when direct-seeded into standing stubble in the semiarid prairie of southwestern Saskatchewan

Non-Peer Reviewe

Estimation of daily soil CO2 emission using instantaneous measurements

Non-Peer Reviewe

Long-term straw management and N fertilizer rate effects on soil organic C and N, and some chemical properties in a Gray Luvisol

Non-Peer Reviewe