Evaluation of Essential Oils against Early Blight (Alternaria solani) of Tomato
K. P. Ragupathi *
Dept. of Seed Science & Technology, TNAU, Coimbatore, India.
P. R. Renganayaki
Dept. of Seed Science & Technology, TNAU, Coimbatore, India.
S. Sundareswaran
Directorate of Seed Center, TNAU, Coimbatore, India.
S. Mohan Kumar
CPMB & B, TNAU, Coimbatore, India.
A. Kamalakannan
Dept. of Plant Pathology, TNAU, Coimbatore, India.
*Author to whom correspondence should be addressed.
Abstract
The fungicidal effect of some essential oils viz., Neem, Eucalyptus, Pongamia, Lemongrass, Thyme and Clove were evaluated against Alternaria solani causing early blight of tomato resulting in severe yield loss. All essential oil treatments showed the significantly varied antifungal activity against the pathogen. Among the in-vitro screened essential oils percent growth inhibition of pathogen was higher in Thyme oil (80%) and it was followed by Clove oil and Eucalyptus oil. Plant biometric observations viz., seed germination (84%) and seedling vigor (1747) was maximum with lower percent disease index (13%) was recorded in Thyme oil treated seeds and seedlings of tomato cultivar PKM 1.
Keywords: Essential oils, Alternaria solani, lemongrass, thyme, clove.