Yield and protein response to N fertilization by different cultivars of spring and durum wheat

Abstract

A field study to determine whether there were differences in the response of CWAD and CWRS wheat to N fertilization was conducted in two soils of southwestern Saskatchewan for four years. Using regression techniques we were able to establish that both wheat classes had the same grain yield and protein concentration response to N availability, and that the differences in grain yield and protein concentration between classes observed in the study arose from differences in the response of the classes to available water. Differences in response to water availability among cultivars within each class were too small to be of practical significance. Recommendations for N fertilization of CWAD and CWRS wheats should be based on an N response common to both wheat classes, and on the ratio of the price of wheat to the cost of fertilizer N for each class.