Nitrogen, phosphorus and zinc management effects on grain yield and cadmium concentration in two cultivars of durum wheat

Cadmium concentration in durum (Triticum turgidum) grain may be influenced by fertilizer management. A 3-yr field study conducted on two Orthic Black Chernozemic soils investigated the effects of banded and broadcast applications of N and P, and applications of Zn fertilizer on the yield and Cd concentration of the grain of two cultivars of durum wheat. Applications of N and P fertilizer increased grain yield of durum wheat when soil nutrient supply was low or yield potential was high, while Zn application generally had little effect on grain yield. Cadmium concentration of durum increased with applications of N and P and was generally unaffected by Zn application. Method of application of N or P did not consistently influence either grain yield or Cd concentration of the grain under the conditions of this study. Where differences due to placement occurred, banded P produced higher grain yield and Cd concentration than application of the same level of P as a broadcast treatment. Cadmium accumulation increased substantially with N and P applications, since both Cd concentration in the grain and grain yield increased with N and P application. Year-to-year variation in Cd concentration in the grain was large, indicating a strong effect of environment on Cd phytoavailability.