Potential of Organic Wastes as Liming Materials in Low Input Rainfed Agricultural System

A field experiment was conducted on an acid soil in a humid tropical Island of Andaman, India to explore the feasibility of using locally available organic wastes as liming materials after suitable composting. The organics such as coconut husk compost, poultry manure, vermicompost and gliricidia were incorporated at the rate of 20 Mg ha-1 and the amendment effect was compared with lime applied at the rate of 4 Mg ha-1. Soil application of composted organic wastes significantly increased the soil pH. The exchangeable Al3+ showed significant reduction in organic amended soils and completely disappeared in poultry manure and lime treated soils. Significant differences were observed in root volume by application of N rich organic materials compared to control (11.7 mm3) and lime (23.3 mm3) application which helped in increasing volume of soil foraged by maize roots. Poultry manure (3.79 t ha-1) and vermicompost (3.73 t ha-1) application recorded on par maize grain yield but significantly higher than the control (1.93 t ha-1). The results showed the potential of poultry manure and coconut husk composted with either poultry manure or gliricidia as alternate liming material for low input agricultural system prevailing in humid tropical Islands.