Availability of fertilizer zinc to corn in a calcareous mineral soil
MacGregor, J.M.; Sajjapongse, A.; Gunderson, O.M.
Soil Science Society of America Proceedings 38(4): 611-616
In field trials in 1962-7 on Zn-deficient silty clay loam, ploughing-in ZnSO4.7H2O at 22.4-44.8 kg Zn/ha resulted in higher leaf Zn contents in maize in all 5 years, whereas the effectiveness of lower rates decreased with time. Grain yields were increased by both ploughing-in and band application of ZnSO4.7H2O until the 5th year. Treating maize seed with Na2Zn-EDTA at 0.01 kg Zn/ha had no effect on leaf Zn or on annual grain yield, but increased the 5-year yield.