Comparative evaluation of homeopathic medicines and bio agents as inducer in induced resistance in Tomato against early blight caused by Alternaria solani Sorauer

Abstract

Early blight caused by Alternaria solani (Sorauer) is the most important and destructive disease of all tomato growing areas of the world causing huge amount of loss as 35-79 per cent in India. The management of the disease is mainly based on cultivation of resistant variety and use of fungicides. However, resistance against pathogen is not a permanent solution and fungicidal application is not eco-friendly and economical. Therefore, inquest for induced defense by certain homeopathic medicines like Phosphorus, Arnica montana, Sulphur, and Silicea terra and bioagents viz. Trichoderma viride, Trichoderma harzianum, Pseudomonas fluorescens and Bacillus subtilis as inducer were assessed during the course of present investigation and their physiological and biochemical activities in tomato plant were ascertained. newlineHomeopathic medicines and bioagents have also played an important role on inhibition of growth and development of pathogen. The maximum inhibition of mycelial growth of A. solani was recorded from Arnica montana at0.20% treatment representing 73.67 % reduction in growth over control. Seedling treatment with inducing agent provides good protection against seed and soil borne infection. Growth promoting effects of the inducers were also perceived. The inducing agents were found to increase shoot length as well as root length over control. Foliar spray with the inducers before pathogen inoculation protected the plants against infection resulting reduced disease severity. newline newline