Table 2 Morphological characters and dimensions (µm), cardinal temperatures (°C) and temperature-growth relations (mm/d) on V8A of Phytophthora castanetorum, P. tyrrhenica, P. tubulina, P. vulcanica and their closest relatives in phylogenetic Clades 7a and 12, respectively. Most discriminating characters are highlighted in bold.

No. of isolates

9

5

10^b

7

5

3^a

7^a

3^a

Sporangia

ovoid, subglobose, obpyriform, globose, (ellipsoid, distorted)

ovoid, obpyriform, distorted, (globose, subglobose, ellipsoid, limoniform)

subglobose, ovoid, obpyriform, peanut, ampulliform, distorted

elongated ellipsoid, elongated ovoid, elongated limoniform

ovoid, ellipsoid, (obpyriform, pyriform)

ellipsoid, ovoid, peanut-shaped, (obpyriform, limoniform)

ovoid, obpyriform, ellipsoid, (subglobose),

ovoid, ellipsoid, (obpyriform, limoniform)

apex

77.4 % papillate, 14.9 % semipapillate; 7.7 % nonpapillate, 4.9 % curved

78 % mono-, bi- or tripapillate; 13.3 % semi-papillate; 8.7 % non-papillate, 4.9 % curved

all papillate, some bi- and tripapillate; often curved

nonpapillate

nonpapillate

nonpapillate

nonpapillate, often pointed

lxb mean

47.0±5.7 × 36.6±3.7

51.6±9.8 × 37.3±7.0

42.4±11.5 × 29.3±13.8

68.4±1.7 × 28.9±1.9

57.3±8.7 × 34.5±4.2

67.0±8.5 × 42.4±6.4

63.7±16.9 × 44.6±8.3

56.1±7.4 × 36.7±5.2

range of isolate means

44.2–48.1 × 35.4–38.3

43.3–57.8 × 31.2–45.0

36.0–49.2 × 23.3–33.7

66.1–70.0 × 27.5–31.9

53.6–61.0 × 31.8–36.4

65.7–70.3 × 30.9–44.4

50.0–78.9 × 36.7–51.2

53.3–58.6 × 33.9–39.4

total range

27.1–74.5 × 18.1–47.9

29.5–98.5 × 19.2–59.2

18.8–112.5 × 13.8–17.5

45.3–110.2 × 16.2–39.4

35.5–80.7 × 22.5–42.9

41.1–85.0 × 24.8–56.9

23.6–124.3 × 21.9–67.3

34.9–74.8 × 22.8–49.7

l/b ratio

1.29 ± 0.15

1.40 ± 0.18

1.45 ± 0.37

2.40 ± 0.18

1.67 ± 0.22

1.60 ± 0.19

1.42 ± 0.19

1.54 ± 0.18

caducity

-

rare

-

-

-

-

-

-

lateral insertion

37.7 %

22.4 %

frequent

exit pores

7.0 ± 1.1

6.4 ± 1.2

6.5 ± 1.2

12.1 ± 2.4

17.0 ± 3.0

15.4 ± 3.4

19.3 ± 4.7

19.7 ± 3.4

zoospore cysts

9.2 ± 1.0

11.7 ± 1.8

9.5 (7.1–12.9)

14.6 ± 2.3

10.0 ± 1.2

11.9 ± 1.8

15.3 ± 2.0

13.3 ± 1.3

Breeding system

homothallic

homothallic

homothallic

homothallic

homothallic

homothallic

homothallic

homothallic

Oogonia

mean diam

32.9 ± 3.0

29.2 ± 4.4

29.4 ± 4.1

37.2 ± 3.3

35.8 ± 3.6

46.2 ± 7.5

37.3 ± 5.4

36.8 ± 3.3

range of isolate means

30.5–34.4

25.4–30.1

25.8–32.0

36.8–40.9

33.6–36.5

41.6–53.3

34.4–39.9

36.0–38.3

total range

24.3–41.7

16.5–42.5

19.0–45.0

25.0–39.3

23.0–16.0

17.9–65.5

19.2–48.4

25.7–12.8

tapering base

61.3% (40–86 %)

48.7 % (30–78 %)

n.a.

-

37.3 % (8–60 %)

-

60.0 % (52–81 %)

47.9 % (32–58 %)

elongated

65.4 % (50–82 %)

59.5 % (36–86 %)

45 % (10–86 %)

-

44.8 % (8–80 %)

-

21.3 % (12–34 %)

19.7 % (4–36 %)

tubular

-

24.5% (21–28 %)

-

-

-

-

-

-

excentric

6.7 % (2–20 %)

5.0 % (2–8 %)

n.a.

-

20.9 % (9–46 %)

-

4.0 % (0–8 %)

5.3 % (2–10 %)

smooth-walled

100 %

100 %

100 %

100 %

100 %

100 %

100 %

34.4% (19–48 %)

Oospores plerotic oospores

64.3 % (50–83 %)

44 % (24–76 %)

mostly aplerotic

>99% (99–100 %)

27.3 % (10–15 %)

30.0 % (12–46 %)

46.3 % (38–53 %)

>99% (99–100 %)

mean diam

28.7 ± 2.6

26.1 ± 3.7

24.7 ± 2.6

33.7±1.3

30.5 ± 3.2

41.3±6.1

33.2 ± 5.3

32.2 ± 2.7

Total range

21.9–38.8

15.7–36.3

18.0–30.0

24.6–39.9

19.7–38.2

12.5–55.0

16.3–45.1

22.7–37.7

wall diam

3.1 ± 0.49

2.0 ± 0.6

2.4 ± 0.56

2.9 ± 1.5

2.4 ± 0.4

4.2 ± 0.7

2.5 ± 0.7

3.1 ± 0.5

oospore wall index

0.51 ± 0.05

0.38 ± 0.08

0.44 ± 0.1

0.41 ± 0.03

0.40 ± 0.06

0.49 ± 0.07

0.38 ± 0.06

0.47 ± 0.06

Abortion rate

21.5 % (18–29 %)

72.3 % (40–91 %)

<10%

5 % (3–7 %)

52.8 % (0–80 %)

6.2 % (3–10 %)

24.9 % (18–31 %)

1.7% (1–2 %)

Antheridia

99 % paragynous

100 % paragynous

100 % paragynous

100 % paragynous

4.7 % amphigynous

100 % paragynous

100 % paragynous

100 % paragynous

size

14.0±2.3 × 10.2±1.6

14.9±3.1 × 10.9±1.7

16.6±6.3 × 12.7±2.5

16.9±4.6 × 12.8±0.13

16.3±3.1 × 12.6±2.3

16.9±3.1 × 13.3±2.5

13.6±2.6 × 10.8±2.1

13.4±2.1 × 10.0±1.7

Chlamydospores

globose

-

rare, in some isolates

-

-

-

-

-

mean diam

29.5 ± 4.9 (17.7–47.0)

17–35

Hyphae

Sympodial branching with protruding tip of mother hypha

Sympodial branching with protruding tip of mother hypha

Sympodial branching with protruding tip of mother hypha

Often inflated tubular or club-shabed

Coralloid

Hyphal aggregations

-

-

-

-

+

-

-

Hyphal swellings

in water; globose, subglobose, limoniform; some catenulate

in water; subglobose, triangular; some catenulate

in water; subglobose, irregular, catenulate

in water; subglobose, irregular, catenulate

in water; subglobose, irregular, catenulate

Maximum temperature

25–<30

25–<30

27.5

25–<30

25–<30

25

30–<35

35

Optimum temperature

20

20

25

25

15

20

25

25

Growth rate at optimum

2.9 ± 0.91

1.7 ± 1.0

3.7

1.1 ± 0.4

1.0 ± 0.1

1.2 ± 0.2

4.9 ± 0.53

4.7 ± 0.61

Growth rate at 20°C

2.7 ± 0.75

1.7 ± 1.0

3.3

1.5 ± 0.3

0.9 ± 0.04

1.2 ± 0.2

4.4 ± 0.59

4.4 ± 0.56