There are a limited number of postemergence (POST) herbicides available
for weed management in mung bean production in Ontario. Five field studies were
conducted in 2010, 2011 and 2012 near Exeter, Ontario and in 2011 and 2012 near
Ridgetown, Ontario to determine the tolerance of mung bean to fomesafen, bentazon,
bentazon + fomesafen and halosulfuron applied POST at the 1X and 2X proposed
manufacturer’s recommended rate. Bentazon caused 5%-29%, 4%-31%, and 2%-18%
injury, fomesafen caused 3%-17%, 1%-7%, and 0%-6% injury, bentazon +
fomesafen caused 6%-40%, 4%-37%, and 1%-20% injury, and halosulfuron
caused 13%-65%, 8%-75%, and 5%-47% injury in mung bean at 1, 2, and 4
weeks after treatment (WAT), respectively. At Exeter, fomesafen had no adverse
effect on height of mung bean but bentazon, bentazon + fomesafen and
halosulfuron decreased mung bean height as much as 5% compared to the untreated
control. At Ridgetown, there was no
decrease in mung bean height due to the herbicides applied. Fomesafen
had no adverse effect on shoot dry weight of
mung bean but bentazon, bentazon + fomesafen and halosulfuron
decreased shoot dry weight of mung beans as much as 43%, 47%, and 57%, respectively.
Fomesafen, bentazon, bentazon + fomesafen and halosulfuron had no adverse
effect on the seed moisture content and
seed yield of mung bean with the exception of halosulfuron applied POST
at 70 g ai ha-1 which increased seed moisture content 0.4% at
Exeter and 1.4% at Ridgetown and decreased yield 16% at Exeter compared to
the untreated control. Based on these results, there is not an adequate
margin of crop safety for bentazon, bentazon + fomesafen and halosulfuron applied POST in mung bean. However,
there is potential for fomesafen applied POST at the proposed manufacturer’s
rate of 240 g ai ha-1 in
mung bean production.
 Guenther, L. (2012) Mung bean has potential for Western Canada.
 Arnold, N.R., Murray, W.M., Gregory, J.E. and Smeal, D. (1993) Weed control in pinto beans (Phaseolus vulgaris) with imazethapyr combinations. Weed Technology, 7, 361-364.
 Malik, V.S., Swanton, C.J. and Michaels, T.E. (1993) Interaction of white bean (Phaseolus vulgaris) cultivars, row spacing, and seeding density with annual weeds. Weed Science, 41, 62-68.
 Chikoye, D., Weise, S.F. and Swanton, C.J. (1995) Influence of common ragweed (Ambrosia artemisiifolia) time of emergence and density on white bean (Phaseolus vulgaris). Weed Science, 43, 375-380.
 Burnside, O.C., Ahrens, W.H., Holder, B.J., Wiens, M.J., Johnson, M.M. and Ristau, E.A. (1994) Efficacy and economics of various mechanical plus chemical weed control systems in dry bean (Phaseolus vulgaris). Weed Technology, 8, 238-244.
 Bauer, T.A., Renner, K.A., Penner, D. and Kelly J.D. (1995) Pinto bean (Phaseolus vulgaris) varietal tolerance to imazethapyr. Weed Science, 43, 417-424.
 Urwin, C.P., Wilson, R.G. and Mortensen, D.A. (1996) Responses of dry edible bean (Phaseolus vulgaris) cultivars to four herbicides. Weed Technology, 10, 512-518.
 [OMAFRA] Ontario Ministry of Agriculture, Food, and Rural Affairs (2012) Guide to weed control. Publication 75. Ontario Ministry of Agriculture, Food, and Rural Affairs, Toronto.
 Senseman, S.A. (2007) Herbicide handbook. 9th Edition. Weed Science Society of America, Champaign, 458.
 Sikkema, P.H., Soltani, N., Shropshire, C. and Cowan, T. (2004) Tolerance of white beans to postemergence broadleaf herbicides. Weed Technology, 18, 893-901.
 Soltani, N., Nurse, R.E., Robinson, D.E. and Sikkema, P.H. (2008) Response of pinto and Small Red Mexican bean to postemergence herbicides. Weed Technology, 22, 195-199.
 Soltani, N., Shropshire, C. and Sikkema, P.H. (2006) Effects of post-emergence application of bentazon and fomesafen on eight market classes of dry beans (Phaseolus vulgaris L.). Crop Protection, 25, 826-830.
 Wilson Jr., R.G. (2005) Response of dry bean and weeds to fomesafen tankmixtures. Weed Technology, 19, 201-206. http://dx.doi.org/10.1614/WT-04-166R
 Bailey, W.A., Wilson, H.P. and Hines, T.E. (2003) Weed control and snap bean (Phaseolus vulgaris) response to reduced rates of fomesafen. Weed Technology, 17, 269-275.
 Soltani, N., Shropshire, C. and Sikkema, P.H. (2012) Response of dry bean to halosulfuron applied postemergence. Canadian Journal of Plant Science, 92, 723-728.
 Silvey, B.D., Mitchem, W.E., Macrae, A.W. and Monks, D.W. (2006) Snap bean (Phaseolus vulgaris) tolerance to halosulfuron PRE, POST, or PRE followed by POST. Weed Technology, 20, 873-876.
 VanGessel, J.M., Monks, W.D. and Quintin, R.J. (2000) Herbicides for potential use in lima bean (Phaseolus lunatus) production. Weed Technology, 14, 279-286.
 Wall, D. (1995) Bentazon tank-mixtures for improved redroot pigweed (Amaranthus retroflexus) and common lambsquarters (Chenopodium album) control in navy bean (Phaseolus vulgaris). Weed Technology, 9, 610-616
 Stewart, C.L., Nurse, R.E., Gillard, C. and Sikkema, P.H. (2010) Tolerance of adzuki bean to preplant-incorporated, pre-emergence, and post-emergence herbicides in Ontario, Canada. Weed Biology and Management, 10, 40-47.
 Sikkema, P.H., Shropshire, C. and Soltani, N. (2009) Response of dry bean to pre-plant incorporated and preemergence applications of S-metolachlor and fomesafen. Crop Protection, 28, 744-748.