Submitted to: Advances in Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/3/2014
Publication Date: 1/20/2014
Publication URL: handle.nal.usda.gov/10113/58459
Citation: Xiang, Y., Herman, T., Hartman, G.L. 2014. Utilizing soybean milk to culture soybean pathogens. Advances in Microbiology. 4:126-132. Interpretive Summary: Culturing microbes dates back to the 19th century when, in 1876, broths based on fresh beef serum or meat extracts were used to grow microorganisms. The culturing of microbes has provided scientific advancements in areas of microbiology, pharmacology, plant pathology, and plant breeding for disease resistance. The use of plant products as a base for making media is common, and commercial products especially from patotoes are widely used in microbilogy laboratories. These commercial products are often expensive and cheaper media can be made from plant material directly, for example soybean seeds. In this study, a comparison was made between soybean milk medium, a product from soybean seeds also referred to as soymilk, and media traditionally used for culturing soybean pathogens to determine if soymilk medium was an effective medium for growth of soybean pathogens. Soymilk used with agar or used alone as a broth was effective in growing nine soybean pathogens. Soymilk used with agar or used alone as a broth may be a viable substitute to replace more expensive processed media. This information could be utilized by microbiologist, soybean pathologists, and other scientists interested in growing microbes in culture.
Technical Abstract: Liquid and semi-solid culture media are used to maintain and proliferate bacteria, fungi, and Oomycetes for research in microbiology and plant pathology. In this study, a comparison was made between soybean milk medium, also referred to as soymilk, and media traditionally used for culturing soybean pathogens to determine if soymilk medium was an effective medium for growth of Colletotrichum truncatum, Fusarium virguliforme, Macrophomina phaseolina, Passalora sojina, Phomopsis longicolla, Phytophthora sojae, Pythium irregulare, Rhizoctonia solani, and Sclerotinia sclerotiorum. Based on radial mycelial colony growth rates, C. sojina grew significantly (P < 0.05) faster on soymilk dextrose agar (SDA) than on V-8 agar, and C. truncatum and F. virguliforme grew significantly (P < 0.05) faster on SDA than potato dextrose agar (PDA). Significantly (P < 0.001) greater masses of sclerotia were produced by S. sclerotiorum grown on SDA as compared to PDA. Soymilk used with agar or used alone as a broth may be an option of replacing more expensive processed media.