Wheat and Barley Responses to Rates of Seeding and Fertilizer in Southwestern Saskatchewan

Research from 1960 to 1968 at Swift Current, Saskatchewan, on orthic brown chernozemic clay loam under semiarid conditions indicated that the seeding rate of hard red spring wheat (Triticum aestivum L.) could be reduced to half of the seeding rate most commonly used by farmers. This study in 1976 and 1977 extended the testing to orthic brown chernozemic loam and heavy clay soils and included fertilizer treatments. Tests were conducted on stubble and fallow land at three locations in 1976 and 1977. Seeding rates were 20, 40, and 60 kg/ha with fertilizer applied at rates of 0-0 (check), 10-9 and 50-22 kg/ha of N and P, respectively. With the exception of barley (Hordeum vulgare L.) on fallow, no significant fertilizer ✕ seeding rate interactions for yield were recorded, indicating that fertilizer rates and seeding rates were factors that operated relatively independently. However, differences in yield between locations were observed. In 1977, a location ✕ seeding rate interaction was obtained on fallow while location ✕ fertilizer interactions on fallow in 1976 and on stubble in 1977 occurred. Fertilizer increased the yield over the check yield for all crops on stubble and fallow. Reducing the seeding rate to 20 kg/ha for wheat and barley on stubble and to 40 kg/ha for barley and durum (Triticum durum Des. F.) on fallow caused no significant reduction in yield. For durum on stubble and wheat on fallow seeding rates of 60 kg/ha were required for maximum yields. The responses of barley and durum to fertilizer and seeding rates were similar to the responses of wheat for yield, N and P content, kermel and volume weight of the grain. Increased rates of fertilizer produced some increases in the N content of the grain, particularly at the highest rates, but both rates reduced the P content. Higher fertilizer rates tended to reduce the kernel and volume weights for all crops. The higher seeding rates reduced the N and P content of the grain, and the kernel weight, but increased the volume weight.