Solvent extraction and antifungal assay of Lawsonia inermis Linn. Against the brown spot fungus Bipolaris oryzae

Abstract

Rice brown spot caused by Bipolaris oryzae is the most devastating pathogen ruining rice production next to sheath rot in Tirunelveli and Thoothukudi districts of Tamil Nadu. This fungus is highly responsible for grain discolouration which ultimately leads to qualitative and quantitative losses in rice grain production. In the current scenario of disease management the hazardous fungicide are being replaced by botanicals. Among the eight botanicals tested against the mycelial growth of B. oryzae by poisoned food technique the leaf extract (10%) of Maruthani (Lawsonia inermis) and Kodukkapuli (Pithecolobium dulce) were highly effective. The antifungal compounds of L. inermis were extracted subsequently with the series of solvents. Acetone and ethanol fractions are found effective and having much antifungal activity on the mycelial growth of B. oryzae.