Influence of interactions of barley cultivars with soil and fertilizer K,and soil pH on grain yield and quality

Summary The interaction of exchangeable soil K with cultivars resulted in differences in grain production by five barley cultivars. The cultivars differed in the amount of exchangeable soil K required to produce maximum yield. Bonanza attained its maximum yield at 183 kg K₂O ha^–1, but Galt did not reach its maximum yield until a high level of exchangeable soil K was reached (252 kg K₂O ha^–1). The other cultivars were within this range. The cultivars also differed in their yield response to applied K fertilizer. Under conditions of growth-limiting K supply, Galt and Gateway were slightly more responsive to the addition of K fertilizer than were Centennial and Conquest, and much more responsive than Bonanza. The interactions of exchangeable soil K and soil pH or soil NO₃–N and soil pH with cultivars indicated differences in acid tolerance of the cultivars. Galt was more pH sensitive than Bonanza.