Author(s): R Wongamthing, Sainamole Kurian P, Surendra Gopal K, Anju C, Rehna Augustine and Sible George Varghese

Abstract: Tomato early blight disease caused by pathogen Alternaria solani is broadly distributed and responsible for severe crop yield loses worldwide. In sustainable agriculture, use of biological agents is an imperative module approach against drastic plant hackers as they facilitate to fight off against phytopathogens by the accumulation of phenolic compounds and defensive enzymes such as Peroxidase (PO), Polyphenol oxidase (PPO) and Phenylalanine ammonia-lyase (PAL). The phylloplane isolates viz, Trichoderma spp. (PF2 and PRF1), Bacillus subtilis (MNB2), Bacillus mojavensis (TB1) and Ochrobactrum sp. (EB1) were evaluated for their antagonistic effect against Alternaria solani in a pot culture experiment. Increased enzymes activity of PO, PPO and PAL was observed in all the treated plants which lead to induced systemic resistance (ISR). Among the antagonists treatments, Trichoderma sp. (PF2) followed by Bacillus subtilis (MNB2) gave the highest activity of oxidative enzymes with good attributes of growth and yield parameters compared to the Control. Foliar application of aforementioned antagonists resulted in disease reduction and improved plant growth in tomato plant. The tested phylloplane isolates may consider as an ideal bio-agents that play a pivotal role in disease management of early blight of tomato plants through induction of induced systemic resistance.

DOI: 10.33545/26174693.2024.v8.i1Sk.447