Differential Response of Crops to Zinc Application in Calcareous Soil

In a field experiment on an alluvial calcareous sandy loam soil the direct and residual effect of zinc were studied on five kharif (monsoon) and five rabi (winter) crops following the rotations rice-rabi maize; kharif maize-gram; finger millet-pea; black gram-barley, and groundnut-wheat. Zinc was applied at the rate of 0, 2.5, 5.0 and 10.0 kg/ha once a year. Visual symptoms of zinc deficiency were observed on most of the crops which did not receive zinc. Application of Zn up to 5 kg/ha significantly increased the grain and straw production whereas at 10 kg Zn/ha level the yields tended to decrease. The magnitude of response differed from crop to crop. Zinc application progressively increased its concentration in grain and straw. The maximum Zn removal was recorded in rice-rabi maize and minimum in groundnut-wheat rotations.