INFLUENCE OF SUGARCANE MONOCROPPING ON RHIZOSPHERE MICROFLORA, SOIL ENZYMES AND NPK STATUS.

Abstract

Monocropping of sugarcane is highly profitable to the farmers and sugar industry, as it reduces the production cost by 30-40%. But productivity of sugarcane under multiratooning is declining by 30-50% every year due to reduction in cane population per hectare in the state of Maharashtra. The objectives of this study were to explore the changes in beneficial and phytotoxic ratoon cane rhizosphere microflora, soil enzymes and soil NPK level under sugarcane monocropping from high recovery zone and medium recovery zone.  The intensive monocropping of sugarcane was found to induce soil sickness due to accumulation of allele chemicals released from sugarcane trash and root exudation, development of phytotoxic microflora and one sided nutrient exhaust. It also caused almost double increase in phytotoxic fungal and bacterial population along with five times more stimulation in the activities of soil enzymes like dehydrogenase, cellulase and amylase. All such alterations correlate with drastic reduction in ratoon cane yield as compared to plant cane.