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In plant disease: General characteristics
Clavibacter, Erwinia, Pseudomonas, Xanthomonas, Streptomyces, and Xylella. With the exception of Streptomyces species, all are small, single, rod-shaped cells approximately 0.5 to 1.0 micrometre (0.00002 to 0.00004 inch) in width and 1.0 to 3.5 micrometres in length. Streptomycetes develop branched mycelia (narrow, threadlike growth) with
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black spot
- In black spot
  …plants caused by species of Pseudomonas bacteria or by any number of fungus species in the genera Asterina, Asterinella, Diplotheca, Glomerella, Gnomonia, Schizothyrium, Placosphaeria, and Stigmea. Infections occur during damp periods and appear as round to irregular black spots on leaves and sometimes on petioles, stems, and flower parts of…
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fruit spot
- In fruit spot
  …caused by Erwinia and some Pseudomonas species are watery to mushy and putrid and follow injuries. Other bacterial and fungal decays (except Pythium and Phytophthora) are generally firm and dry. Fruit-infecting organisms may attack other plant parts. Insects commonly transmit the infecting microorganisms and provide the entry wounds. Spots and…
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wilt
- In wilt: Bacterial wilt
  >Pseudomonas, and Xanthomonas, induces stunting, wilting, and withering, starting usually with younger leaves. Stems, which often shrivel and wither, show discoloured water-conducting tissue. A bacterial ooze is often evident when infected stems are cut and squeezed. Rapidly expanding, dark green, water-soaked areas or streaks may…
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