To study the availability of boron status under different agro climatic zone in soils of Assam

Abstract

A study was undertaken to assess the available boron status. Two hundred surface soil samples representing four agro-climatic zones of Assam were collected covering fifty locations in each zone and analyzed for hot water soluble boron (HWS-B) and some important soil physico-chemical properties. A wide variation was observed in HWS-B and physico-chemical properties among the four agro-climatic zones of Assam. Soils from Upper Brahmaputra Valley Zone recorded higher mean value of HWS-B, clay, organic carbon, CEC, available nitrogen and phosphorus than that of other three agro-climatic zones. HWS-B exhibited a significant positive correlation with organic carbon, CEC, available nitrogen and available sulphur indicating their dominant influence on boron status of these soils. Among the zones, soils from Lower Brahmaputra Valley Zone showed the highest deficiency in HWS-B with 36 per cent and the lowest deficiency was found in Upper Brahmaputra Valley Zone with 28 per cent.