Effect of graded levels of Zn in combinations with microbial inoculation on maize grain quality in black and red soils

Abstract

Field experiment was conducted in 2015 for black and red soils in order to study the maize grain quality viz., Protein, Tryptophan, Starch and Amylose using Arbuscular Mycorrhizal (AM) fungi and Zinc Solubilizing Bacteria (ZSB) in combination with graded levels of ZnSO4. Treatment consisted of two factors viz., microbial inoculation (M1: control, M2: AM fungi, M3: ZSB and M4: M2+M3) and graded levels of ZnSO4 (S1: 0, S2: 12.5, S3: 25, S4: 37.5, S5: 50 kg ha-1 and S6: 0.5% foliar spray @ 45 and 65 DAS) replicated three times in RBD. In both the soils, the treatment combinations M4S5 had registered highest true protein and crude protein than rest of the treatment combinations. The increases were to the tune of 40.0 and 36.3% over control in black soil while 39.6 and 39.0% in red soil followed by M4S4. Irrespective of the soils, the treatment combinations viz., M4S5 recorded the highest tryptophan values over other treatment combinations. The highest starch and amylase content were recorded in the treatment M4S5 followed by M4S4.