Use of plant pathogens as bioherbicides to manage weeds in horticultural crops

Certain fungal, bacterial, and viral pathogens can be mass-produced and used as biological herbicides to control weeds in crops. This approach, referred to as the "bioherbicide" or the "inundative" biological control strategy, is based on our ability to manipulate certain weed-pathogen systems to cause highly damaging levels of disease epidemics during critical periods of weed interference and by doing so minimize present and future weed impacts in crop fields. Worldwide about 10 bioherbicide products have been developed and used commercially to manage weeds in various crops, including several horticultural crops. In fact, one of the first bioherbicides registered by the EPA was developed for control of a weed in Florida citrus. Currently, we are developing bioherbicides to manage weeds in citrus, vegetables, pastures, and natural areas, targeting pigweeds (Amaranthus spp.), purple nutsedge (Cyperus rotundus L.), several invasive grasses, dodder (Cuscuta spp.), and tropical soda apple (Solanum viarum Dunal). The following is a brief overview of this topic.