Submitted to: Advances in Applied Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/1/2008
Publication Date: 11/1/2008
Citation: Pielach, C.A., Roberts, D.P., Kobayashi, D.Y. 2008. Metabolic behavior of bacterial biological control agents in soil and plant rhizospheres. Advances in Applied Microbiology. 65:199-215. Interpretive Summary: Soilborne plant pathogens cause diseases that result in major economic losses to farmers in the United States. Biological control measures for these diseases need to be developed due to environmental hazards and other problems associated with existing control measures. Unfortunately, inconsistent performance by biological control agents during large-scale applications has diminished use of these organisms in production agriculture. This chapter reviews the impact of factors existing in environments where biological control organisms are used and the impact that these factors have on performance by biological control organisms. This information will be useful to scientists devising strategies to improve biological control through enhanced consistent performance by biological control agents.
Technical Abstract: Biological control provides an attractive alternative to chemical pesticides for the control of plant diseases. To date, however, few biocontrol products have been developed successfully at the commercial level. This stems largely from variability in disease control performance that is often observed not only with end-users, but also experimentally in large scale field studies. Significant effort has been made to overcome the inconsistencies observed with biological control, including improving our knowledge of the ecology of biocontrol agents, as well as understanding the basic mechanisms by which biocontrol agents function to control disease. Intense characterization at the molecular and biochemical levels over the past 20 years has provided insight into roles for specific genes in biocontrol, the regulatory pathways that lead to their expression, and how plant, soil and environmental factors influence expression of these traits in biocontrol agents. With the development of new molecular and biochemical methods, we are gaining a better understanding of microbial metabolic activity in soil, including how it relates to cellular metabolic energy status of rhizobacteria, nutrient availability in association with plants, and biological control efficacy. Improving our understanding of biological control at this level is necessary to provide better insight, and thus improving consistency, to biological controls.