Use of paper mill sludge as an alternative liming material and its impacts on light interception radiation utilization efficiency of groundnut in acid soils of eastern India.

Abstract

Acid soils affect the productivity and radiation interception in crops directly or indirectly by influencing the availability of plant nutrients, crop growth and biomass. Thus, the maintenance and management of acid soils are very much important to obtain higher productivity of the crop on sustainable basis. In this study, possibility of using low cost liming materials like paper mill sludge (PMS) to ameliorate acid soil was investigated and its impacts on productivity, light interception, radiation utilization efficiency of groundnut were assessed under tropical monsoon climate of eastern India. The PMS used in this study contained 32.5% calcium carbonate which was applied at different rates viz., 20, 30, 40, 50 and 60% of lime requirements (LR), 4-5 weeks before sowing of the crop. Results were compared with control (no lime treatment, 0% LR). The PMS enhanced soil pH, nutrient availability, biomass, leaf area and yield and in turn, it increased light interception, radiation use efficiency significantly when applied up to 50% LR. No significant effect on crop growth, water productivity, light interception were observed when it was applied at 60% LR.