Heat shock response in tomato brassinosteroid mutants indicates that thermotolerance is independent of brassinosteroid homeostasis

► We assessed the induction of thermotolerance in tomato mutant seedlings with altered BR homeostasis. ► We showed that thermotolerance is independent of endogenous brassinosteroid levels. ► The heat shock-mediated oxidative stress depends on brassinosteroid levels. ► The tomato curl3−abs mutant with altered sensitivity to brassinosteroids is heat tolerant.