Crops
Other alterations and abnormalities on the stem
(browning, tanned appearance, bursts,
emission of adventitious roots ...)
In addition to the more or less canker changes observed on tomato stalks, other deteriorations and anomalies may appear on this organ; Figures 1 to 3 illustrate some of them.
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| Figure 1 | Figure 2 | Figure 3 |
In the presence of such symptoms, you can make the following assumptions:
- either parasitic
- Pectobacterium carotovorum subsp. carotovorum (figure 1)
- Pseudomonas corrugata
- Virus divers
- Aculops lycopersici
- either non-parasitic
- Hail
- Physiological emission of aerial adventitious roots
- Various phytotoxicities
Several bacteria are likely to cause more or less extensive browning on tomato stems: Pectobacterium spp. and Pseudomonas corrugata (responsible for black pith). In fact, in many cases, these bacteria first colonize and damage the inside of the stem before attacking the external tissues.
Note that the symptoms they cause on the outside of the stem are often quite comparable, which is confusing. In addition, their development is also favored by the same conditions:
- plants cultivated rather under shelter;
- plants that are often very vigorous, with a fleshy and thick stem and lush vegetation;
- a high humidity prevailing in the crop or under the shelter;
- the presence of free water on the plants;
- a period of cloudy weather before the onset of symptoms.