Sustainable Management of Tomato Early Blight with Plant Extracts

Abstract

This study focused on developing eco-friendly management strategies for early blight disease in tomatoes, caused by Alternaria solani, through the use of botanical extracts from eight plants: Neem, Prosopis, Nerium, Senna, Lantana, Pungam, Coconut, and Calotropis. The research was carried out at the Agricultural College and Research Institute in Vazavachanur, Thiruvannamalai, to assess these botanicals in vitro and in vivo effectiveness against the pathogen. In laboratory conditions, the extracts were tested at a 10% concentration, and their ability to inhibit the pathogen's mycelial growth was evaluated. Neem leaf cold extract exhibited the highest inhibition at 77.8%, followed by Nerium at 75.9%, while Senna showed limited effectiveness. In a field trial using the PKM-1 tomato variety, the lowest disease index was observed with neem leaf extract spraying (28%) and Nerium extract (30.2%), indicating their potential as effective alternatives for managing early blight.