Weed Control J 2026; 25: e202600886

Research Article

Herbicide selectivity and interference from Commelina benghalensis in Vigna cultivars

DOI: 10.7824/wcj.2026;25:00886

Abstract:

Background:

Vigna bean species have garnered increasing global interest due to their nutritional value and adaptability to unfavorable environmental conditions. Their expansion into Brazil’s Cerrado region, however, necessitates reliable herbicide strategies for effective weed suppression under high weed pressure, particularly from Commelina benghalensis.

Objective:

This study assessed the selectivity of commonly used herbicides and the potential interference of C. benghalensis in different Vigna cultivars.

Methods:

Two greenhouse experiments were conducted in 2022 and 2023 using cultivars of V. unguiculata (Itaim, Nova Era, Rouxinol, Tumucumaque), V. radiata (Mungo Verde MG2), and V. angularis (Azuki). The treatments included S-metolachlor, bentazon + imazamox, quizalofop + fomesafen, clethodim + fomesafen, lactofen + haloxyfop, as well as a weed-free and interference condition with C. benghalensis. Herbicide injury, growth variables, and yield parameters were measured.

Results:

S-metolachlor markedly reduced seedling emergence in Azuki and Mungo Verde MG2. Although transient injury symptoms were observed in several cultivars, recovery occurred in most cases over time. Significant yield reduction was limited and cultivar-specific. Genetic variability among cultivars influenced herbicide tolerance, indicating the need for selective management strategies. Notably, none of the cultivars exhibited yield reduction due to interference by C. benghalensis.

Conclusion:

These findings support the potential use of selective herbicide programs for Vigna cultivation, while highlighting the importance of cultivar-dependent tolerance mechanisms.