Bioherbicides: An Overview

Authors: Rosskopf, Erin; CHARUDATTAN, RAGHAVAN - University Of Florida; BRUCKART, WILLIAM - Retired ARS Employee

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 11/14/2017
Publication Date: 12/12/2017
Citation: Rosskopf, E.N., Charudattan, R., Bruckart, W. 2017. Bioherbicides: An Overview. In: Zimdahl, R.L., editor. Integrated weed management for sustainable agriculture. Cambridge, UK:Burleigh Dodds Science Publishing. p. 367-392.

Interpretive Summary: Among agricultural pests, weeds are the most important. Without weed management, crop and animal production, and aquatic and forestry endeavors, are severely curtailed or eliminated. The relative importance of weeds as pests is evident from the large proportion of herbicide applied, relative to other pesticides. In the United States, more than 50% of all pesticides purchased are for weed control. There are many approaches to management of weeds, including cultural and mechanical approaches, such as tillage, plastic cover, and hand-weeding. Biological control is another tool that can be used to control weeds, particularly in large areas, such as public lands, where the application of herbicides is too expensive, or where there are ecological sensitivities, as well as in organic production systems. Materials made for weed control that contain either natural products derived from plants or microbes are referred to as bioherbicides. Some bioherbicides that are commercially available are based on plant oils, like citrus or clove oil and some contain living organisms or the metabolites of the organisms. Bioherbicides that contain organisms are thoroughly tested for safety before they are used and must be cleared by the United States government before they can be sold or applied.

Technical Abstract: Weed control is one of the greatest concerns in agriculture and land management. Although chemical control (herbicides) is the most commonly used method in developed countries, there are many invasive species that occur on public and private lands for which chemical control is not economically feasible. In addition, there are social, economic, and political drivers that place pressure on producers and managers to decrease their overall use of pesticides. Bioherbicides are an option for non-chemical weed control. Materials classified as bioherbicides include products based on natural compounds derived from plants or microbes. Many of these are commercially available, some of which can be used in organic production systems. Two other types of bioherbicides involve that application of living organisms and/or their metabolic products. The classical approach to microbial bioherbicide application involves the release, after significant host range and safety testing, of an imported organism from the origin of the invasive weed. A second approach, referred to as the bioherbicide or inundative approach, utilizes an endemic pathogen applied in much greater quantity than would be found naturally.