Virulence Composition of Phytophthora sojae in Michigan
Open Access
- 1 October 2001
- journal article
- Published by Scientific Societies in Plant Disease
- Vol. 85 (10), 1103-1106
- https://doi.org/10.1094/pdis.2001.85.10.1103
Abstract
Knowing the virulence composition of Phytophthora sojae is important for the management of Phytophthora root and stem rot of soybean. Plant samples were collected in Michigan from diseased plants in soybean fields with Phytophthora root and stem rot symptoms. Eighty-seven isolates of P. sojae were evaluated for virulence using 13 differential soybean cultivars. Rps 3b, 3a, 1b, 1k, and 6 were resistant to 81, 77, 74, 69, and 66% of the isolates, respectively, while Rps 1a and 7 were resistant to only 12 to 13% of the isolates. Races 2, 25, 41, and 44 of P. sojae were identified among the isolates and reported for the first time in Michigan. Virulence formulae of 69 isolates did not match those of currently known races of P. sojae. Nine isolates were considered nonpathogenic. Incorporating Rps genes 1b, 1k, 3a, 3b, and 6 in soybean cultivars with good field tolerance, in conjunction with other control measures, should offer improved protection of soybeans from Phytophthora root and stem rot in Michigan.Keywords
This publication has 16 references indexed in Scilit:
- New Races of Phytophthora sojae with Rps1-d VirulencePlant Disease, 1997
- Low Concentrations of the Isoflavone Genistein Influence in vitro Asexual Reproduction and Growth ofPhytophthora sojaePhytopathology®, 1996
- Phytophthora sojaeRaces Have Arisen by Clonal Evolution and by Rare OutcrossesMolecular Plant-Microbe Interactions®, 1994
- Genetic Crosses between Physiologic Races of Phytophthora sojaeExperimental Mycology, 1993
- In Planta Formation of Heterokaryons ofPhytophthora megaspermaf. sp.glycineaPhytopathology®, 1990
- New Physiologic Race ofPhytophthora megaspermaf. sp.glycineaPlant Disease, 1986
- Glyceollin Accumulation in Soybean Lines Tolerant toPhytophthora megaspermaf. sp.glycineaPhytopathology®, 1985
- Isolating Phytophthora megasperma f. sp. glycinea from soil with a baiting method that minimizes Pythium contaminationSoil Biology and Biochemistry, 1982
- Genetic Evidence for Diploidy in Phytophthora megasperma var. sojaePhytopathology®, 1977
- New Races 5 and 6 of Phytophthora megasperma var. sojae and Differential Reactions of Soybean Cultivars for Races 1 to 6Phytopathology®, 1976