Herbicide-induced disease resistance and associated increases in free amino acid levels in melon plants

Abstract Melon seedlings grown in the presence of low levels of the dinitroaniline herbicide trifluralin and the chloroacetamide herbicide acetochlor to induce resistance to Fusarium oxysporum f. sp. melonis (the cause of fusarium wilt) had elevated levels of free amino acids. This response with trifluralin is similar to that previously described for tomato seedlings treated with various dinitroanilines. In tomato, however, acetochlor did not induce resistance to F. oxysporum f. sp. lycopersici or result in elevated levels of amino acids.