Deficiency of manganese is alleviated more by low zinc than low copper in wheat

Abstract

Wheat (Triticum aestivum L.) var. Sonalika was grown in purified sand in complete nutrient solution (normal), deficient manganese (Mn) (0.0055 mg L^‐1), deficient copper (Cu) (0.0065 mg L^‐1), deficient zinc (Zn) (0.0065 mg L^‐1), deficient ?n/deficient Cu, deficient ?n/deficient Zn, deficient Cu/deficient Zn, and deficient ?n/deficient Cu/deficient Zn treatments. The deficiency of Mn decreased the biomass, concentration of Mn, chlorophyll, sugars, Hill reaction activity, acid phosphatase activity, and increased that of peroxidase and polyphenol oxidase. The magnitude of Mn deficiency effects was mitigated to variable extent when Mn was deficient along with deficient Cu and/or deficient Zn. The effects of either Cu or Zn deficiency viz., intensification of foliar symptoms, decrease in biomass, leaf Cu/Zn, seed yield and starch content were increased further in combined deficiency of Cu and Zn. The stimulation in acid phosphatase and decrease in the activity of polyphenol oxidase and carbonic anhydrase in Cu or Zn deficient leaves were further aggravated when both Cu and Zn were deficient together. All these changes reveal a synergism between Cu and Zn in wheat.