Efficacy of Non-Conventional Chemical Inducers against Fusarium oxysporum Inciting Wilt in Chilli

Abstract

Chilli wilt incited by Fusarium oxysporum is the most devastating disease, causing substantial yield losses throughout chilli growing areas of the world. Fusarium oxysporum is a soil-borne fungus which survives for several years in soil. The disease is favoured by high temperature and high moisture, this condition plays significant role in development of wilt symptoms. The disease management using chemicals is economically not feasible and is also unsafe for the environment. Due to growing public awareness to environment and human health, need of the hour is to find alternate approaches for disease management. Therefore, to investigate induction of systemic resistance against Fusarium oxysporum in chilli. Different non-conventional chemical inducers like salicylic acid (SA), jasmonic acid (JA), Indole acetic acid (IAA), Indole butyric acid (IBA), chitosan, salicylic acid nano formulation and chitosan nano formulation were used in an experiment conducted in Department of plant pathology, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana. These non-conventional chemicals with four concentrations 25, 50, 75 and 100 µg/ml were evaluated for their antifungal activity against Fusarium oxysporum under in vitro condition using poison food technique with four replications. It was found that the highest mycelial growth inhibition was observed in salicylic acid nano formulation (79.73%) at 100 µg/ml concentration followed by Jasmonic acid (77.12%) at 100 µg/ml concentration and the lowest growth inhibition was recorded in Indole acetic acid (27.15%) at 100 µg/ml concentration. The same trend was observed when chilli varieties Pusa Jwala (susceptible) and Pusa Sadabahar (moderately resistant) were tested with the two best and the least effective non-conventional chemical inducer obtained in vitro for measuring the disease severity in screen house. This insight clarifies the scope of using non-conventional chemical inducers as an effective disease management strategy against Fusarium wilt of chilli.