Zearalenone production in groundnutV KMehanauthorT NBhavanishankerauthorDMcDonaldauthorFusariutn spp. are important components of the seed mycoflora of healthy 4! undnut pods (Jackson, 1965; Joffe, 1969; McDonald, 196'3). and are also i~ plicated in pod rots (Mercer, 1977; Mehan er al., 1981). Some species of this genus are well-known producers of mycotoxins such as zearalenone. diacetoxyscirpenol and neosolaniol (Mirocha et al., 1976; Ueno. 1977). Zearalenone, an oestrogenic mycotoxin, has mainly been found in cereal grains and their products (Mirocha and Christensen, 1974). Zearalenone has been reported to occur naturally in sesame (Mirocha et al., 1976) and in groundnuts (Mehan and McDonald, 1982). This chapter reports the natural occurrence of zearalenone and the effects of cultural conditions on its production in groundnut seeds by a toxigenic strain of F. o.rysporum.Groundnut1985Conference or Workshop Item