Growing degree day trends on the semiarid prairie of southwestern Saskatchewan

Non-Peer Reviewe

Temperature trends in the semiarid prairie of southwestern Saskatchewan

Non-Peer ReviewedPreviously, we had analyzed long-term weather data (from 1950 to 1997) to study the annual as well as seasonal change in air temperature within an approximately 15000 km2 area in the semiarid prairie near Swift Current, SK (Cutforth et al. 1999; Cutforth 2000). We found that the average annual maximum (Tmx) and minimum (Tmn) air temperatures had increased linearly with year. Seasonally, we found that the average Tmx and Tmn for January through April (JFMA) had also increased linearly from 1950 to 1997, as had the average Tmn for May through August. Average air temperatures for September through December (SOND) did not change with year. Generally, JFMA experienced the largest warming trend between 1950 and 1997, whereas temperatures during SOND did not change with year

Temperature trends in southwestern Saskatchewan revisited

Non-Peer Reviewe

Seasonal drought occurrence in the semiarid prairie surrounding Swift Current from 1999 to 2003

Non-Peer Reviewe

Yield adjustment by canola under different plant populations in the semiarid prairie

Non-Peer Reviewe

Measurement of water use by canola with sap flow gauges

Non-Peer Reviewe

The effect of row spacing on the harvestable yield and dry matter production of Russian wild ryegrass

Non-Peer Reviewe

Plant temperature of canola direct seeded into standing stubble

Non-Peer Reviewe

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