Weed Control in New Plantings of Steroid-Producing Dioscorea Species

Abstract

Preemergence flame weeding followed by postemergence herbicide treatment was the best procedure found for controlling weeds in field plantings of two Dioscorea species. Of eight herbicides tested in one or more of five experiments, norea [3-(hexahydro-4,7-methanoindan-5-yl)-1,1-dimethylurea] gave the best weed control without crop injury. Two applications of norea (3.8 kg/ha each) controlled most weeds for one growing season. Better control resulted when plots were flamed one or two times before crop emergence and treated one or two times subsequently with norea. Although new growth developed in most cases when emerged Dioscorea shoots were destroyed by flaming, yields from plots so treated were low.