Management of Zinc for Rice in Sodic Soils

Abstract

The Influence of amendments on reclamation as well as the availability of plant nutrients will vary. The response of crop for the applied Zn will also vary with amendments. However, field experiment was conducted in sodic soil with various amendments viz., gypsum @ 50 % GR + green manure (6.25 t ha-1), green leaf manure (12.5 t ha-1) and press mud (10 t ha-1) as main-plot treatments. Different levels of zinc sulphate viz., 50, 100 and 150 percent of recommended dose as basal with and without foliar spray of ZnSO4 @ 0.5 per cent at panicle initiation (PI) and heading stage were imposed as sub-plot treatments. The rice (CO 52) was used as test crop. The results of field experiment revealed that reclamation of sodic soil with gypsum @ 50% GR + green manure @ 6.25 t ha-1 and ZnSO4 application @ 100% recommended dose (25 kg ha-1) along with foliar spray of 0.5% ZnSO4 at panicle initiation and heading stages found to be the best for getting higher yield of rice in sodic soils. For unreclaimed sodic soil, ZnSO4 application @ 150% recommended dose (37.5 kg ha-1) along with foliar spray of ZnSO4 @ 0.5% at panicle initiation and heading stages is found to be best. The amendments application significantly improved the physicochemical properties, exchangeable cations, available NPK, DTPA-micronutrients of soil. It also increased the uptake of NPK and DTPA-micronutrients of soil. The growth and yield parameters also showed a significant response for reclamation and ZnSO4 application. The application of gypsum + green manure (G+GM) or green leaf manure (GLM) or press mud (PM) can be effectively used as an amendment for the reclamation of sodic soil. The gypsum +GM exhibited its superiority over others.