Gray speck disease and halo blight are actually manganese deficiencies. Gray speck is gray brown or dead spots on the leaf. Manganese levels in plants Excessively high calcium and phosphorus can require more manganese. Concentration of manganese in crops and forages is dependent on soil factors, plant species, stage of maturity, yield, crop management, climate and soil pH. Manganese is highly concentrated in outer layers of grains. Restoring manganese to deficient plants Spray with manganese sulfate precipitated with lime.
Manganese oxide spray less residue on the leaves.
It has been investigated in relation to epilepsy, and people suffering from this disorder have depressed amounts of manganese in their bloodstreams. Papavasiliou et al 1979 reported that humans with convulsive disorders, including epileptics, showed whole blood manganese concentrations significantly below normal. Daily requirements for manganese Adult human nutrition required about 2.5 to 5 mg a day, with recommendations as high as 3 to 9 mg a day. A very high dosage of manganese will reduce storage and utilization in man. In the human body, it is in relatively high levels in the liver, bones, pancreas and kidney.