Seed Yield Potential of Five Wheat Species/Cultivars without and with Phosphorus Fertilizer Application on a P-Deficient Soil in Northeastern Saskatchewan

Abstract

In the Canadian Prairies, many soils on organic farms are low in available phosphorus (P). Previous research has shown that wheat species/cultivars vary in their sensitivity to P deficiency, yield re-sponse to applied P fertilizer, P uptake and P use efficiency on P-deficient soils. A 3-year field ex-periment was conducted from 2012 to 2014 on a P-deficient soil at Kelvington, Saskatchewan, Canada, to determine the potential of five wheat species/cultivars (Spelt and Kamut representing " ancient " , Red Fife representing " old " , and Unity and Goodeve representing " modern " wheat spe-cies/cultivars) for seed yield, protein concentration (PC) in seed, partial factor of productivity (PFP, kg seed kg −1 of N applied), total N and P uptake, P use efficiency (PUE, kg seed kg −1 of P ap-plied) and % recovery of applied P in seed under zero-P and with P fertilizer (triple superphos-phate) applied at 20 kg P ha −1 . Seed yield, PFP and PUE were determined in all 3 years, but PC, to-tal N and P uptake, and % recovery of applied P in seed were determined only in 2012. There was a marked and significant response of seed yield and PFP of all wheat species/cultivars to P fertil-izer in all 3 years, but the actual seed yield and PFP, without and with applied P fertilizer, as well as PUE, varied with species/cultivar in different years. On the average of 3 years, seed yield and PFP were greatest for Unity in both without and with applied P fertilizer treatments. Seed yield increases from applied P were 1111, 773, 890, 1810 and 2028 kg·ha −1 , respectively, for Spelt, Ka-mut, Red Fife, Unity and Goodeve. Total N and P uptake were lowest for Kamut and greatest for Unity or Goodeve, in both without and with applied P fertilizer treatments. Percent recovery of * Corresponding author. S. S. Malhi et al. 225 applied P in seed was greatest for Goodeve or Unity and lowest for Spelt or Kamut. Protein con-centration in seed usually decreased with P fertilizer, and wheat species/cultivars with higher PC in seed usually showed greater reduction in PC with P application. In conclusion, the findings sug-gest that the " modern " wheat species/cultivars Unity or Goodeve might be more suitable for high sustainable seed yield and total P or N uptake than the " ancient " wheat species Spelt and Kamut or the " old " wheat cultivar Red Fife, especially when adequate amount of P fertilizer is applied to op-timize crop production on a P-deficient soil.