Tank mixture additives approach to improve efficiency of bentazon against broadleaf weeds in peas

Abstract

Efficiency of different tank-mixed additives with bentazon at half rate was investigated on (Malva parviflora) and other broad leaf weeds compared with bentazon at the full recommended rate without additives in peas in open field. All the tested additives enhanced the efficiency of bentazon at the half rate. Nonyl phenol and toximol S proved to be the most effective additives in comparison with the full rate treatment. The tested treatments did not show any significant effect on chlorophyll content and soil microorganisms. Bentazon residues were determined in certain treatments to investigate the effect of the tested additives on bentazon deposition. Samples were extracted using QuEChERS method and residues were determined using LC-MS/MS. Residues after 24 hours in the half rate treatment reached 4 times lower than the Maximum Residues Limit (MRL) (0.11 mg kg⁻¹), compared to the full rate treatment (0.51 mg kg⁻¹), that was slightly above the MRL.

Keywords:

• Bentazon
• weed control
• spray tank additives
• broadleaf weeds
• peas
• soil microorganisms

Acknowledgment

The authors wish to acknowledge Mr. Elmeleigy, Managing Director of Blue Nile Egypt, for covering the field trial costs. Also, we gratefully acknowledge Professor Richard Brown and Dr. Joe Hill-Cousins (School of Chemistry, University of Southampton, UK) for proofreading the manuscript.