Physiologic specialization of Diaporthe phaseolorum var. caulivora in soybean.

Reference Report for ADL87084532

Title:	Physiologic specialization of Diaporthe phaseolorum var. caulivora in soybean.
Authors:	Higley, P.M., Tachibana, H.
Source:	Plant Dis. 1987, 71(9):815-817
Abstract:	Two isolates of Diaporthe phaseolorum var. caulivora (D. p. var. caulivora) from Mississippi and one from Iowa were used to inoculate seedlings of four soybean cultivars [Glycine max] adapted to Mississippi and six to Iowa. The percentages of resistant, moderately susceptible, and highly susceptible plants were recorded for each cultivar. The three D. p. var. caulivora isolates showed physiologic specialization. Some variability in plant response occurred. Because soybean cultivars have not been selected for resistance to stem canker, they may be genotypically heterozygous for response to D. p. var. caulivora. Soybean cultivars Blackhawk, Harosoy, L4404, Nathan, Tracy M, and Williams were susceptible to the Iowa isolate and resistant to the Mississippi isolates; Clark, J77-339, and Pike were susceptible to all three isolates. It is proposed that the Iowa isolate be designated race 1 and the Mississippi isolates be designated race 2.

Funded by the USDA-ARS. Developed by the USDA-ARS SoyBase and Legume Clade Database group at the Iowa State University, Ames, IA

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