Eco-Friendly Alternatives for Managing Plant Diseases: Lessons from Ageratum conyzoides -A Review

Abstract— Ageratum conyzoides, commonly known as billygoat weed or goatweed, poses a significant threat to agricultural ecosystems, negatively impacting crop productivity and biodiversity. Due to environmental concerns associated with conventional control methods, this comprehensive review critically examines the current state of biological control strategies for A. conyzoides. The study explores three major categories of biological control agents: insects such as the Ageratum gall fly (Procecidochares utilis) and the Ageratum stem-boring weevil (Listronotus setosipennis), which disrupt weed growth through gall induction and stem boring, respectively; fungal pathogens that induce diseases compromising weed vigor; and herbivorous livestock, particularly controlled grazing by goats and sheep, as a natural means of suppression. The review evaluates the efficacy of these agents while considering key environmental factors such as climate and soil characteristics. Special emphasis is placed on minimizing non-target effects through host specificity assessments and optimizing biocontrol implementation strategies. Additionally, challenges including the potential development of resistance in A. conyzoides, the necessity of integrating multiple control measures, and existing knowledge gaps are discussed. This study underscores the importance of continued research and the adoption of integrated pest management (IPM) approaches to achieve sustainable and ecologically sound weed control. In conclusion, this review provides valuable insights into eco-friendly weed management practices, contributing to sustainable agricultural production and biodiversity conservation.