Multiple resistance in Indian hedge mustard in SA
Biological control of weeds is broadly defined as the use of an agent, a complex of agents, or biological processes to bring about weed suppression. All forms of macrobial and microbial organisms are considered as biological control agents. Examples of biological control agents include, but are not limited to: arthropods (insects and mites), plant pathogens (fungi, bacteria, viruses, and nematodes), fish, birds, and other animals. Biologically based weed management is a much broader category of approaches that may include gene modification, genetic processes, and gene products. Human activities intended to remove weeds directly or indirectly, such as hand-weeding and burning, deliberate uses of plant competition, allelopathy, and cultural and soil management practices that alter the biotic balance of soil are considered important adjuncts to biological control in integrated weed management systems.
Biological control has been used successfully as a practical and economically affordable weed control method in many situations. While there has been an increase in interest in biological control over the past 20 years, earlier instances of its use date back to 200 years. Classical biological control, which is biological control of non-native invasive weeds with natural enemies originating from the native range of the weed, has proven a viable strategy for managing weeds in areas subjected to low-intensity management, such as rangelands, forests, preserved natural areas, and some waterways. The use of an inundative method, also called the bioherbicide strategy, where an organism is applied to achieve rapid reduction in weed populations, has also proven successful in some instances. In the future, pathogens may also be used to introduce or alter specific genes to control growth, flowering, seed set, and/or competitiveness of weeds.