Characterization of volatile organic compounds from potential plant growth-promoting bacteria

Abstract

Microorganisms play important roles in plant growth and development. The use of biofertilizers for crop production is not only beneficial to the plants but can serve as a form of sustainable agriculture. Volatile Organic Compounds (VOC’s) are metabolites produced by microorganisms known to play a role in plant growth and defense. In this study, the VOC’s produced by bacteria isolated from the shoots of grape vines were used to test the growth enhancing ability of the bacteria. Four bacterial isolates were characterized for their ability to enhance soybean growth using the volatile organic compounds produced. All of the four isolates showed no plant growth promoting abilities. The four bacteria were identified to be Stenotrophomonas rhizophila, Bacillus proteolyticus, Paenibacillus alvei and unknown. Only Senotrophomonas rhizophila was identified with certainty. The volatile profile of each bacterium was analyzed, and various compounds known to be produced by soil bacteria, in addition to some novel compounds were identified. An additional experiment was conducted by placing the S. rhizophila bacteria directly into the soil along with biochar. This experiment was not completely conducted due to the disruption caused by the COVID-19 shutdown. Based purely on observation, more extensive plant growth was present for the S. rhizophila treatment.