A trial was carried out in order to study the performance of oxadiazon on yield of transplanted lettuce. The treatments were: oxadiazon granular formulation at rates of 1.0,1.5 and 2.0 kg/ha applied after transplanting and pre emergence of weeds; oxadiazom emulsifiable concentrate at 1.0 kg/ha applied before and after transplanting both as preemergence of weeds. Two controls were used: one without any control of weeds and another free from weeds 33 days after transplanting. Oxadiazon gave good control of Portulacca oleracea L, Galinsoga parviflora Cav., Amaranthus hibridus L, Digitaria sanguinalis (L.) Scop, and Eleusine indica (L.) Gaertn. up to 51 days after application. Except for oxadiazon emulsifiable formulation, when applied after transplanting, no phototoxicity to lettuce was observed with the herbicide whether applied at preemergence or before transplanting. The treatment with the emulsifiable formulation showed severe reduction on number and yield of harvested lettuce.
lettuce; oxadiazon; weeds