Table 1. Races of Phytophthora sojae Summarized Through 1996

Published Virulence
Race Eight Genesa Five Genesb Type Culturec Verified on 13 Genesd
1 7 . . .  B77R1.55  2,3c,7*
2 1b,7  . . .  C14R2.15  1b,7
3 1a,7  . . .  B135R3.40  1a,7
4 1a,1c,7  . . .  B102R4.72  1a,1c,5,7*
5 1a,1c,6,7  3c,4  D45R5.10  1a,1c,2,4,6,7

6   

1a,1d,3a,6,7   

2,3c,4,5   

D46R6.25   

1a,2,3a,3c,4,5,6,7*

7   

1a,3a,6,7   

2,3c,4,5   

B67R7.54   

1a,2,3a,3c,4,5,6,7

8   

1a,1d,6,7   

2,4   

D33R8.15   

1a,1d,2,4,6,7

9   

1a,6,7   

3c,4   

D5R9.11   

1a,2,3b,3c,4,5,6,7*

10   

1b,3a,7   

5   

C20R10.3   

1b,3a,3b,3c,5,7*

11   

1b,6,7   

4   

D15R11.18   

1b,7*

12   

1a,1b,1c,1d,1k,3a   

. . .   

D16R12   

1a,1b,1c,1k,5*

13   

6,7   

. . .   

D66R13.3   

4,6,7*

14   

1c,7   

. . .   

B8R14.22   

1c,2,5,7*

15   

3a,7   

5   

D55R15   

1a,1b,1c,1k,7*

16   

1b,1c,1k   

5   

C9R16   

1a,2,3a,3c,4,6,7*

17   

1b,1d,3a,6,7   

3b,4,5   

D35R17.2   

1b,1d,2,3a,3b,3c,4,5,6,7*

18   

1c   

. . .   

D36R18.35   

1a,1c,5

19   

1a,1b,1c,1d,1k,3a   

5   

D19R19   

1a,1b,1c,1d,1k,2,5,7*

20   

1a,1b,1c,1k,3a,7   

. . .   

C24R20   

1a,1b,1c,1d,1k,3b,3c,5,7*

21   

1a,3a,7   

5   

C25R21.6   

1a,2,3a,3c,5,7*

22   

1a,1c,3a,6,7   

4,5   

Not available   

. . .

23   

1a,1b,6,7   

. . .   

Not available   

. . .

24   

1b,3a,6,7   

4,5   

Not available   

. . .

25   

1a,1b,1c,1k,7   

. . .   

B208R25.81   

1a,1b,1c,1k,7

26e   

1b,1d,3a,6,7   

4,5   

D40R26.10   

1b,1d,2,3a,3b,3c,4,5,6,7*

27f   

1b,1c,1k,3a,6,7   

4   

Not available   

. . .

28g   

1a,1b,1k,7   

5   

C2R28.5   

1a,1b,1k,2,3c,5,7*

29g   

1a,1b,1k,6,7   

4   

B151R29.22   

1a,1b,1k,2,3b,3c,4,5,6,7*

30g   

1a,1b,1k,3a,6,7   

2,4,5   

C1R30.33   

1a,1b,1k,2,3a,3c,4, 5,6,7*

31g   

1b,1c,1d,1k,6,7   

2,4   

B17R31.16   

1b,1c,1d,1k,2,4,6,7

32g   

1b,1k,6,7   

2,4   

B175R31.24   

1b,1k,2,4,6,7

33h   

1a,1b,1c,1d,1k   

5   

Not available   

. . .

34h   

1a,1k,7   

. . .   

Not available   

. . .

35i   

1a,1b,1c,1d,1k   

2,3b,5   

C21R12.29   

1a,1b,1c,1d,1k,2,3b,5

36j   

3a,6   

4,5   

Not available   

. . .

37j   

1a,1c,3a,6,7   

3b,3c,4,5   

Not available   

. . .

38k   

1a,1b,1c,1d,1k,3a,6,7   

. . .   

Not available   

. . .

39k   

1a,1b,1c,1k,3a,6,7   

. . .   

Not available   

. . .

a Genes 1a, 1b, 1c, 1d, 1k, 3a, 6, and 7. Identification of most races is based on differential reactions on these eight Rps genes. Data for races 1–25 are from Ward, E. W. B., 1990, The interaction of soya beans with Phytophthora megasperma f. sp. glycinea, pages 299-310 in: Biological Control of Soil-borne Plant Pathogens, D. Hornby, ed., C.A.B. International, Wallingford, England.

b Genes 2, 3b, 3c, 4, and 5. Differential resistance genes were not used for original descriptions. Reactions for races 1–25 on these five additional genes are from Ward, 1990. The source of data for expanded differentials is not indicated.

c Representative culture is on file at Ohio State University. Numbers with decimals are single-oospore lines. All others are mass cultures.

d Virulence of representative culture. Asterisks indicate a difference from the original description.

e Source: B. L. Keeling (unpublished).

f Source: Wagner, R. E., and Wilkinson, H. T., 1992, A new physiologic race of Phytophthora sojae on soybean, Plant Dis. 76:212.

g Source: Schmitthenner et al., 1994, for eight Rps genes; additional reactions unpublished.

h Numbers reserved for new races from Indiana (T. S. Abney, unpublished).

i Virulence phenotype derived from race 12 in Ohio (R. G. Bhat and A. F. Schmitthenner, unpublished).

j Data for new races from Japan from Förster et al., 1994.

k Data for new races from Arkansas from Henry, R. N., and Kirkpatrick, T. L., 1995, Two new races of Phytophthora sojae, causal agent of Phytophthora root and stem rot of soybean, identified from Arkansas soybean fields, Plant Dis. 79:1074. Not tested on additional five differential Rps genes.