The invention relates to haptenes, conjugates, marked derivates and antibodies for fludioxonil. The invention also relates to the use of conjugates of fludioxonil as test antigens or immunogens for producing antibodies of said fungicide; and to the use of the marked derivatives of fludioxonil as test antigens. The invention further relates to a method for analysing fludioxonil using the antibodies produced, sometimes together with test antigens that are conjugates or marked derivatives. The invention also provides a kit for analysing fludioxonil comprising antibodies of said fungicide, sometimes together with test antigens that are conjugates or marked derivatives.