Combined foliar selenium and zinc biofortification in field pea (Pisum sativum): accumulation and bioavailability in raw and cooked grains

Millions of people have an inadequate intake of selenium (Se) and zinc (Zn), and foliar biofortification may minimise these problems. To evaluate the efficacy of combined foliar Se and Zn fertilisation in field pea (Pisum sativum L.) grains, foliar Se and Zn applications were tested individually and in all combinations (0, 0.03% or 0.06% (w/v) NaSeO4, and 0, 0.25% or 0.5% (w/v) ZnSO4.7H(2)O) at early grain filling. Plant growth was not influenced by any of the treatments. There was a positive relationship between total Se or Zn concentration in raw or cooked grains and respective Se or Zn application dose. Grain Zn accumulation was positively influenced by the combined application of Se and Zn. Grain cooking caused a slight decrease in grain Se (by 7.4%) and Zn concentrations (by 19%); however, cooking enhanced Zn bioavailability. The consumption of 100g of cooked, biofortified field peas would provide similar to 50% of recommended daily intake of Zn and 45% of Se. The present study successfully biofortified field peas with Se and Zn, with the combined foliar application of Se and Zn being the best option.