EVALUATION OF PROPHYLACTIC APPLICATION OF ACIBENZOLAR-S-METHYL FOR SYSTEMIC ACQUIRED RESISTANCE AGAINST BACTERIAL SPOT OF TOMATO

Abstract

One of the synthetic compounds of plant origin that activates plant resistance is acibenzolar-s-methyl (ASM). A preliminary prophylactic measure against bacterial spot disease of tomato was carried out through foliar spray of ASM before transplanting at 25 and 50 ppm concentrations on Kerewa, NG/DE/MAR/01/019 and UTC-18 tomato genotypes while untreated tomato plants served as control. Results showed that the highest disease incidence (95.62%) was recorded in untreated NG/DE/MAR/01/019 which was significantly higher (p ≤ 0.05) than 10.01%, incidence observed in UTC-18 at 50 ppm. Disease severity of 0.33 observed in Kerewa at 50 ppm was significantly lower (p ≤ 0.05) than 4.93 severity recorded in NG/DE/MAR/01/019 in plots without ASM application. Kerewa treated with 50 ppm concentration yielded 64.16 g/plant which was significantly higher (p ≤ 0.05) than 12.31 g/plant yields obtained from in plots without ASM application. The study revealed the promising prophylactic foliar application of ASM at 50 ppm which could be an effective measure for tomato growers against yield loss caused by bacterial spot disease of tomato.