MOVEMENT AND FATE OF FLUORODIFEN‐1′‐14C IN CUCUMBER SEEDLINGS

Abstract

Summary. Autoradiographs and liquid scintillation counts of cucumber (Cucumis sativus L. cv. Ashley) seedlings indicated rapid absorption and translocation of radioactivity from fluorodifen‐1′‐14C (p‐nitrophenyl‐α,α,α‐trifluoro‐2‐nitro‐p‐tolyl ether labelled with 14C in the 1 position of the p‐nitrophenyl ring). After 24 h in 1 mg/1 of fluoro‐difen‐1′‐14C, 25% of the absorbed radioactivity was translocated from the roots.Cucumber seedlings degraded fluorodifen‐1′‐14C via a pathway similar to that reported for peanut seedlings but at a slower rate. The major degradation products were p‐nitrophenol and an unidentified polar compound (Unknown I). More rapid absorption and translocation coupled with slower degradation by cucumber as compared with peanut seedlings are factors which may contribute to the susceptibility of cucumber to fluorodifen.