
Important Phytopathogenic Bacteria
Important Phytopathogenic Bacteria
Sr.No |
Genus |
Family |
Gram Reaction |
Characters |
Symptoms produced on host |
Example |
1 |
Pseudomonas |
Pseudomona deveae |
-Ve |
1. Rod straight to curved, size 0.5-1 X 1.5-4 mue m, one to many polar flagella.2.Colonies not yellow, do not produce acid from lactose. |
Leaf spot, blights, vascular wilts, soft rots, canker. |
1. Brown rot or bacterial wilt of potato.2 Bacterial wilt of brinjal and tomato. |
2 |
Xanthomonas |
Pseudomona deveae |
-Ve |
1. Straight rods, size 0.4-1X 1.2 -3m. One polar flagellum present.2. Colonies yellow due to Xanthomonadin, produce acid from lactose. |
Leafspot, fruit spots, blight, canker |
1. Citrus canker, 2. Black arm of cotton,3.Blight of paddy. |
3 |
Agrobacterium |
Rhizobiaceae |
-Ve |
1. Rod shaped, size 0.8 X 1.5 -3 mue m. 1 to 4 peritrichous flagella.2. Colonies mostly white do not hydrolyze starch. |
Crown Gall |
Crown Gall of stone fruit roses. |
4 |
Erwinia |
Enterobacteriaceae |
-Ve |
1. Straight rods, size 0.5-1, 0-3.0 mue m , several peritrichous flagella. |
Fire blight, wilt soft rot. |
1. Fire blight of apple.2. Soft rot of vegetables. |
5 |
Clavibactor (Corynebacterium) |
Enterobacteriaceae |
+Ve |
Straight to straightly curved rods, 0.5-0.9X 1.5 -4.0Mue m. non motile but some species are motile by one or two polar flagella. |
Wilt |
Wilt of potato ad Tomato |
6 |
Streptomyces |
Streptomycetaceae |
+Ve |
Slender branched hyphae without cross walls 0.5-2 mue m diameter. |
Scab |
Potato scab |