Occurrence of putatively resistant plantago in the winter rainfall region of South Africa: a survey

Abstract

Globally glyphosate is the most widely used herbicide. The alternative in many cropping situations is paraquat. After many years of success, neither herbicide could control plantago (Plantago lanceolata L., also ‘English plantain’) in Robertson. A survey was carried out by sending a questionnaire to agrichemical personnel to document the areas with poor plantago control using glyphosate and paraquat in the Western Cape province of South Africa. Recipients were asked to list localities with plantago not eliminated by glyphosate and paraquat, plantago populations that are not controlled by other herbicides apart from glyphosate and paraquat, other herbicides apart from glyphosate and paraquat that eliminate plantago, the history of herbicides applied in those areas and the total number of hectares involved. Survey data were obtained for 21 areas, which spanned over 6 583 ha. There were minimal differences in the type of herbicides applied in the different areas across the province. Most of the respondents reported that both glyphosate and paraquat were failing to control plantago. It appears as if the occurrence of difficult-to-control plantago is more widespread than initially thought. In future, a more detailed survey encompassing the entire country should be carried out to assess the extent of this problem. This will allow weed management strategies to be prioritised to deal with the troublesome plantago weed.