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Table 6 Inoculation and incubation conditions and disease scoring scales used in the four tests of this study

From: The overlapping continuum of host range among strains in the Pseudomonas syringae complex

Test

A-1998

B-2008

C-2013

D-2017

Date of inoculations

 Block 1

Feb-June 1998

Mar-June 2008

Mar-June 2013

May–June 2017

 Block 2

May-Sept 1998

July-Nov 2008

  

# Plants/spp./strain/block

3

3

4

5

Total # plants tested/ strain/plant species

6

6

4

5

Age of plants

Dicots: 2-leaf stage (2 trifoliate leaves for bean plants), except peas which were inoculated at the 4-leaf stage. Monocots: 2–3 leaf stage.

Annual plants: one month after sowing (3 to 5 true leaves); 2-year-old Prunus spp.; 3-month-old hazelnut, kiwifruit, oleander and poplar plants

All plants: one month after sowing (2–6 true leaves)

Inoculum concentration

5 × 107 to 1 × 108 CFU/mL

108 CFU/mL

108 CFU/mL

Inoculation of herbaceous plants

Infiltration in leaf blade near the base of the leaf (ca. 50 μL)

10 droplets (10 μL) on a leaf and 1 droplet (10 μL) injected into stem on each plant.

Infiltration in leaf blade near the base of the leaf (10 μL) after wounding the site with a sterile plastic stick.

Inoculation of woody plants

  

1 droplet (10 μL) on a scar at the petiole-stem junction, sealed with parafilm.

 

Scoring method

0: apparent no reaction;

1: HR-like reaction that does not evolve;

2: symptoms on < half of leaf;

3: symptoms on > half of the leaf blade.

0: no apparent reaction;

1: < 5 lesions/leaf, no symptoms on stems;

2: 5–10 lesions/leaf, no symptoms on stems; 3: > 10 lesions/leaf, no symptoms on stems; 4: some dead leaves, no symptoms on stems;

5: leaf score 1 with lesions on stems or petioles < 5 mm long;

6: leaf score 2 with lesions on stem or petiole from 5 to 10 mm;

7: leaf score 3 with necrosis on stem or petiole > 10 mm;

8: dead plant

0: no apparent reaction;

1: weak symptoms, no necrosis;

2: necrosis at point of inoculation without spreading;

3:-necrosis up to 25% of leaf blade;

4: necrosis from 25 to 50% of leaf blade;

5: necrosis for > 50% of leaf blade;

6: wilting of entire leaf.

Scoring dates (days after inoculation)

2 and 7 days

 

Herbaceous plants: 5, 10 and 15 days. Woody plants: 15, 30, 45, 60 days

2 and 6 days