Department of Soils, Punjab Agricultural University, Ludhiana, 141 004
In a 2-years field experiment on ‘Blood Red’ cultivar of sweet orange, 1 to 3 sprays of 0.15, 0.30 or 0.45 per cent acidic ZnSO4.H2O solutions and 0.45 or 0 60 per cent alkaline ZnSC >4.7H2O solutions were tested. Acidic solutions of 0.15 and 0.30 per cent compared to alkaline solutions of 0.45 and 0.60 per cent ZnSO4 were more efficient in enchancing the Zn concentration in the leaves. Two and 3 sprays of 0.15 per cent acidic solutions were better than 1 or 2 sprays of 0.45 per cent acidic solutions. Though the Zn concentration in sprayed leaves increased from deficient (16 ppm) to more than the adequate level (25 ppm), it was not readily translocated from the old to the new flush.
