American Journal of Plant Sciences, 2021, 12, 558-565 https://www.scirp.org/journal/ajps ISSN Online: 2158-2750 ISSN Print: 2158-2742 DOI: 10.4236/ajps.2021.124036 Apr. 16, 2021 558 American Journal of Plant Sciences Tolerance of Four Market Classes of Dry Beans to Tribenuron and Carfentrazone Applied Preplant Nader Soltani * , Christy Shropshire, Peter H. Sikkema Department of Plant Agriculture, University of Guelph, Ridgetown, Canada Abstract Limited information is available on the sensitivity of dry beans to tribenuron and carfentrazone applied preplant (PP). Four field trials were conducted at Exeter and Ridgetown, ON, Canada in 2019 and 2020 to determine the toler- ance of azuki, kidney, small red and white beans to glyphosate (1800 g·ae·ha −1 ) + tribenuron (15 g·ai·ha −1 ), glyphosate (1800 g·ae·ha −1 ) + carfentrazone (35 g·ai·ha −1 ) and glyphosate (1800 g·ae·ha −1 ) + tribenuron (15 g·ai·ha −1 ) + carfen- trazone (35 g·ai·ha −1 ) applied PP 1 - 2 days prior to seeding dry beans. Glypho- sate + tribenuron, glyphosate + carfentrazone, and glyphosate + tribenuron + carfentrazone, applied PP, caused 5%, 5% and 9% bean injury at 1 WAE; 7%, 6% and 10% bean injury at 2 WAE and 6%, 5% and 8% bean injury at 4 WAE, respectively. At 8 WAE, there was 0, 1% and 4% injury in azuki bean; 1%, 2% and 2% injury in kidney bean; 3%, 2% and 3% injury in small red bean; and 6%, 3% and 2% injury in white bean with glyphosate + tribenuron, glyphosate + carfentrazone, and glyphosate + tribenuron + carfentrazone ap- plied PP, respectively. The injury was significantly greater with glyphosate + tribenuron in small red and white beans compared to the azuki and kidney beans. There was no difference between injury levels among market classes of dry been with glyphosate + carfentrazone or glyphosate + tribenuron + car- fentrazone applied PP. There was no effect of glyphosate + tribenuron, gly- phosate + carfentrazone and glyphosate + tribenuron + carfentrazone on dry bean plant stand, maturity and seed yield. However, dry bean biomass was reduced as much as 15% with glyphosate + tribenuron and 13% with glypho- sate + tribenuron + carfentrazone compared to the untreated control. Dry bean height was reduced 4% with glyphosate + tribenuron + carfentrazone but was not affected with other treatments. Based on these results, there is potential for using glyphosate plus tribenuron or carfentrazone for preplant weed management in dry bean production. How to cite this paper: Soltani, N., Shrop- shire, C. and Sikkema, P.H. (2021) Toler- ance of Four Market Classes of Dry Beans to Tribenuron and Carfentrazone Applied Preplant. American Journal of Plant Sci- ences, 12, 558-565. https://doi.org/10.4236/ajps.2021.124036 Received: March 3, 2021 Accepted: April 13, 2021 Published: April 16, 2021 Copyright © 2021 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access