Benzoic acid may act as the functional group in salicylic acid and derivatives in the induction of multiple stress tolerance in plants

Benzoic acid, sulfosalicylic acid and methyl salicylic acid were evaluated for their regulatory role in inducing multiple stress tolerance in bean (Phaseolus vulgaris cv Brown Beauty) and tomato (Lycopersicum esculentum cv Romano) plants. All three molecules were effective in inducing tolerance to heat, drought and chilling stress similar to that reported previously for salicylic and acetylsalicylic acids. Benzoic acid is effective at lower concentrations than salicylic acid or its derivatives. The benzoic acid structural portion is common to all five molecules and is the most likely basic functional molecular structure imparting stress tolerance in plants.