In 1979 and 1980 eight herbicides have been tested with tree doses increased in arithmetic progression by "rentability" trials in irrigated area at low élévation. Five are retained and are available to be advised by extension services: Butraline : 2 kilos/hectar, Chloramben : 3 kilos in green pod bean fields; Difenamid: 5 kilos in Tomato, Sweet Pepper, Sweet Patato, f i e 1 d s ; Metribuzin at 4-5 kilos in Yam culture; Naptalame at 4,5 kilos in Cucurbits in fersiallitiques clay soils.