The evaluation of new harvest aid herbicides for dry bean (Phaseolus vulgaris L.) production in Manitoba
Field experiments were conducted at Carman, Manitoba to determine the effect of tank-mixing different contact herbicides with glyphosate and time of application of harvest aid herbicides on residue accumulation in dry bean seed and the effect of tank-mixing a contact herbicide with glyphosate on weed control. Carfentrazone-ethyl in mixture with glyphosate was the least effective harvest aid herbicide and did not fully desiccate plant parts or reduce glyphosate residues in the seed to less than 2 ppm. Saflufenacil, diquat, flumioxazin, and glufosinate in mixture with glyphosate effectively desiccated all plant and reduced glyphosate residue accumulation in the seed. Saflufenacil in mixture with glyphosate provided the most consistent efficacy on three weed species. Time of application of harvest aid herbicides influenced residue accumulation and yield; however, all harvest aids applied at or after 75% pod colour change had no negative effect on yield and significantly reduced the risk of residue accumulation.
herbicide, glyphosate, desiccant