Anti-bacterial activity

Brinjal (Solanum melongena L.) is an important vegetable crop of Solanaceae grown throughout the world. Leaf spot and stem canker disease of brinjal is caused by Xanthomonas axonopodis pv. vesicatoria (XAV) in the major growing areas of India. Leaf extract of approx 31 medicinal plants at various concentrations (100, 50 and 25%) were tried to know their antimicrobial activities against XAV in using filter paper disc assay, seeded agar and seed treatment methods. In this study aqueous leaf extracts of Cassia fistula and Catharanthus roseus (47.71% and 39.96%) at 25% concentration followed by Lawsonia inermis and C. roseus (30.98% and 40.15%) at 100% and 50% concentration were found most effective against the pathogen in standard blotter method as compared to check. The high inhibition zone (IZ) and activity index (AI) was shown by Saraca asoca (100%) followed by Withinia somnifera (50%) and Lantana camara (25%) in filter paper disc assay and seeded agar methods. The present study showed these botanicals effective against the pathogen or reduction in the disease incidence and improves the seed germination significantly.