Studies on Systemic Acquired Resistance in Tomato Against Alternaria Solani

Abstract

Alternaria solani is a destructive pathogen to the tomato crop causing heavy losses. The present work was designed during 2015-16 to evaluate the efficacy of Bion and salicylic acid as early blight disease suppressors as well as their use as plant activators under greenhouse conditions. The current study was carried out at field area of Plant Pathology University of Agriculture Faisalabad. Foliar and seedling root dipping application of Bion and salicylic acid (125 ppm and 2 mM) not only reduced the disease severity but also enhanced the plant growth. Maximum disease severity was observed in infected control while minimum disease severity was observed in case of Bion with foliar application in both years. A remarkable increase was observed in Chlorophyll a, b, root fresh/dry weight, photosynthetic rate, shoot fresh/dry weight and growth attributes when A. solani inoculated tomato plants were treated with foliar sprays of Bion. A significant healing to cell membrane was observed to reduce the electrolyte leakage in case of Bion and SA application through foliar spray in inoculated plants. Total soluble carbohydrates and total soluble protein contents are increased when Bion was applied through foliar application as compared to seedling root dipping. Increasing trend was observed in 2nd year of study. It is concluded that foliar application of Bion could be more effective in managing the Alternaria solani as well as in enhancing the growth and yield of tomato.