The effect of applied micronutrients (Cu, Zn, Mn and B) and chloride on annual canarygrass

Abstract

Annual canarygrass is highly responsive to chloride (Cl-) fertilizer for increasing grain yield. This responsiveness to Cl- raises the question of whether annual canarygrass is similarly responsive to other micronutrients. The effect of micronutrients, Cu, Zn, B and Mn with the basal rate of N, P, K, S, Cl-, on annual canarygrass, was studied using two application methods, soil (side-band at seeding) and foliar (3-6 leaf and flag leaf emergence). Over four years, field research was conducted at two Saskatchewan locations, Indian Head and Melfort using a randomize complete block design (RCBD). A foliar application after flag leaf emergence of either Cu, Zn or Mn provided the best method to increase the concentration of that micronutrient in the leaf tissue during seed filling. Boron concentrations in the leaf were increased during seed filling by soil or foliar treatments containing B at different site-years. Zinc, Cu, and B had no impact on grain yield. A foliar application of Mn affected grain yield at one of 6 site-years and requires further investigation. As expected, soil application of macronutrients + Cl- increased grain yield between 29 and 187% compared to unfertilized treatment in five of six site-years. Melfort in 2015 and 2016, had low levels of tissue Cl- in control treatment. The largest grain yield increases occurred at these sites, suggesting that early season tissue testing maybe use to identify Cl- responsive fields of annual canarygrass. Annual canarygrass is not responsive to Cu, Zn, and B but may be responsive to Mn.