Harnessing Organic Defence Inducers (SA, BTH, CHITOSAN) for Effective Management of Fusarium Wilt in Lentil

Background: Lentil (Lens culinaris Medik.) is a crucial pulse crop globally, valued for its nutritious seeds but significantly affected by Fusarium wilt caused by Fusarium oxysporum f.sp. lentis. Traditional management often relies on synthetic fungicides, which can harm the environment. This study explores the potential of organic defense inducers viz; salicylic acid (SA), benzothiadiazole (BTH) and chitosan (Cs) in managing Fusarium wilt sustainably. Methods: The effects of these inducers were tested at concentrations of 100 ppm, 500 ppm and 1000 ppm on lentil plants, focusing on defense enzyme activity, disease incidence and yield. Result: Results showed that the application of these inducers significantly reduced disease incidence and increased yield under field conditions. Notably, enzyme activities of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), peroxidase (PO) and catalase increased substantially. PAL, PPO and PO showing a 10 to 12-fold increase 24 hours post-inoculation and Catalase, 48 hours after inoculation. The most effective inducer found was SA at a concentration of 1000ppm followed by BTH and Chitosan. These findings suggested that organic defense inducers effectively enhance the resistance of lentil plants to Fusarium wilt by promoting systemic acquired resistance (SAR), offering a sustainable approach to crop protection and improved yields.