dl-β-Amino butyric acid induced resistance in tomato against root-knot nematode Meloidogyne incognitaunder salt stress condition

Induced resistance techniques for plant disease management are one of the robust and constructive approaches against plant pests. The present study conducted to trigger the plant-mediated resistance in tomato cv. “K-21” against Meloidogyne incognitaby the involvement of dl-β aminobutyric acid (BABA) under salt stress conditions. Results indicate that seedlings elicitors (dl-β aminobutyric acid) strongly suppressed multiplication of nematode population. At the same time, we could not observe this effect in an inoculated control. Additionally, treated tomato roots with BABA and BABA, coupled with NaCl, showed significant improvement in growth parameters and phenolic compounds. Application of BABA (1.21 mM) + NaCl (100 mM) in combination significantly reduced the root-knot index by 48%. Whereas the same combination significantly improved the phenolic compounds and dry weight content up to 75% and 64% respectively. The minute amount of BABA, in combination with salt stress, resulted in greater efficacy as compared to the higher quantity of BABA (2.42 mM) that might be the cause of synergistic interaction. However, the lowest % increase in phenolic compounds by 60% and decrease of the root-knot index by 40% as we observed in the highest dose of BABA (4.84 mM). Findings of our study suggest that the application of BABA alone and in combination with salt is a promising tactic to inflate the tomato resistance against M. incognitathat might be associated with the enhanced defence response in tomato. Moreover, the stress modulation reaction of BABA under salt stress would be linked with resistance in plants.