Chemical Weed Control in Foxtail Millet (Setaria italica L.)

Foxtail millet (Setaria italica L.) is cultivated world wide for human and animal consumption. Because of drought and salt tolerance, millets can be cultivated in the areas affected by drought and salt stress conditions in the country. Weeds are the major obstacles in increasing the productivity of millets. Since now, there has been no remarkable research and suitable herbicides available for weed control in foxtail millet fields during the post-emergence stage. In the present study, we investigated the efficacy of some herbicides on weeds grown in the field and their safety on foxtail millet simultanously.

A field study was conducted to evaluate the efficacy of herbicides for weed control in foxtail millet (Setaria italica L.) in Agricultural and Natural Resources Research and Education Center of Khorasan Razavi Province, in Mashhad in 2012 growing season. The experiment was conducted in a completely randomized block design with four replications. Treatments were consisted of the post emergence application of dual purpose herbicides including: metsulfuron-methyl+ sulfosulfuron (Total® WG) 32 g active ingredient (a i) ha-1, sulfosulfuron (Apirus® WG) 19.95 g a i ha-1, oxadiazon (Ronstar® SC) 1000 g a i ha-1, mesosulfuron+ idosulfuron (Atlantis® OD) l8 g a i ha-1, isoprotron+ diflophenican (Panther® SC) 1100 g a i ha-1, anilofus+ ethoxysulfuron (Sunrice Plus® EC) 945 g a i ha-1, oxadiargyl (Topstar® 30 EC) 1200 g a i ha-1, and grass killers including: fenoxaprop-p-ethyl (Puma Super®) 55.2 g a i ha-1, diclofop-methyl (Illoxan® EC) 867.5 g a i ha-1, pinoxaden (Axial® 100 EC) l50 g a i ha-1, clodinafop (Topik® 240 EC) 192 g a i ha-1, pinoxaden+ clodinafop (Traxos® EC) 300 g a i ha-1 plus hand weeding and weedy checks.

Results showed Amaranthus retroflexus (L.) Chenopodium album (L.), Portulaca oleracea (L.) were dominant broadleaved weed species and Echinocloa crus-galli (L.) P.Beauv. and Setaria viridis (L.) P.Beauv. were dominant narrowleaved weed species in the field. Density and dry matter of dominant weed species were significantly decreased by dual purpose and grass killer herbicides. Because of severe damage on foxtail millet, application of fenoxaprop-p-ethyl, diclofop-methyl, pinoxaden, clodinafop, pinoxaden+ clodinafop, metsulfuron-methyl+ sulfosulfuron, sulfosulfuron, mesosulfuron+ idosulfuron are not recommended to be used for weed control in foxtail millet fields.

Application of oxadiargyl, oxadiazon, isoprotron+ diflophenican, and anilofus+ ethoxysulfuron showed suitable weed control and caused no adverse effect on biological and grain yield of foxtail millet and therefore can be recommended to be used for weed control in foxtail millet fields.