VIEW ARTICLE

Influence of Temperature on Phymatotrichum Sclerotial Formation and Disease Development. Stuart D. Lyda, Associate Professor of Plant Pathology, Department of Plant Sciences, Texas A&M University, College Station 77843; Earl Burnett, Research Soil Scientist, USDA, ARS, Blackland Conservation Research Center, Temple, Texas 76501. Phytopathology 61:728-730. Accepted for publication 28 January 1971. DOI: 10.1094/Phyto-61-728.

Phymatotrichum omnivorum cultured in sterilized soil containing grain sorghum formed sclerotia at temperatures of 15 to 35 C. Sclerotial production reached a plateau after 8 weeks at 30 C and after 11 weeks at 20 C. When sclerotia were used as inoculum to infest soil, Phymatotrichum root rot developed on cotton more rapidly at 27 C than at 22 C. No disease developed at 12 or 17 C. More sclerotia were recovered from artificially infested soils held at 12 C than at 17, 22, or 27 C. At 27 C, these sclerotia germinated and caused root rot of cotton.