Erroneous classification of Brassica juncea L. in South African studies: consequences for agricultural extension services

Abstract

Agricultural extension services play a crucial role by providing expert guidance on enhancing production and processing and facilitating the dissemination of knowledge and scientific findings into practical use. For this reason, researchers must generate accurate information for agricultural extension officers to relay to the ultimate beneficiaries - the farmers. In this paper, we highlight an instance of misidentification by researchers about one of South Africa's extensively researched vegetables, Brassica juncea L. Due to its broad adaptability, this crop has been the focus of numerous South African studies aimed at maximising its production for resource-poor farmers. Regrettably, the accumulated research on B. juncea reveals a prevalent issue of inconsistent naming and classification, leading to confusion with Chinese cabbage (Brassica rapa subs. chinensis). Such inaccurate species identification fosters a disjointed body of knowledge, potentially generating conflicting results and thereby restricting the applicability of the research findings to farmers and other stakeholders. This literature review examines 20 years of South African research to guide future studies and extension efforts on B. juncea. It underscores the necessity for accurate species identification and nomenclature, thereby enhancing the reproducibility and relevance of research outputs.