Celery Septoria

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

Septoria, also called celery leaf blight or late leaf burn, is an extremely harmful disease that often manifests itself in fairly large areas. Since this ailment develops mainly in rainy cold weather, most often its manifestations are observed in autumn or spring. Damage to celery as a result of septoria infection leads to a decrease in keeping quality and yield of root celery, as well as to the death of leaf celery

A few words about the disease

On the petioles and leaves of celery, when affected by septoria, pale small chlorotic specks of yellowish shades are formed, reaching 1 cm in diameter as the adversity develops and acquiring a brownish color. And around the spots, you can see reddish edges. Severely affected leaves curl up and dry out rather quickly, and their petioles often break. Occasionally, depressed oblong specks of pale brown color are formed on the stalks of the testes and leaf petioles. On the surface of all spots, pycnidia are formed in huge quantities - black dots, which are the fruiting bodies of the causative agent of a destructive disease.

The seeds of infected crops, even in the absence of specific external symptoms, are also covered with destructive fungal pycnidia. An unpleasant disease can manifest itself both on tiny seedlings and on adult crops. And it is widespread almost everywhere.

Septoria is caused by a fungus called Septoria apii Chest. Fungi-causative agents of septoria blight overwinter in plant debris and in the soil.

Such an unpleasant disease spreads through plant debris and infected planting material. In plant debris and infected seeds, the pathogen can persist for up to three years. Conidia can be dispersed by wind, irrigation water or rain. They can also be transferred during the care of growing crops and with the help of insects. And the pathogen easily penetrates into vegetation through leaf surfaces or through stomata.

High air humidity to a large extent contributes to the rapid spread of Septoria. Also, this is very favored by temperatures in the range from 22 to 28 degrees. The disease also intensifies if manure or nitrogen fertilizers are introduced into the soil in excessive doses.

How to fight

When growing celery, you should follow the basic rules for growing this crop. It is imperative to carefully monitor the spread of weeds on the site. Crop rotation rules should not be ignored either - a three-year crop rotation will be a good helper in growing healthy crops. Sowing umbrella plants early will also do a good job. Well-drained and light areas are the best for growing celery. And cultivate varieties that are better resistant to this disease.

Testes with signs of infection must be discarded, and it is important to try to take only healthy seeds. Before sowing seeds, it is recommended to pre-treat them by keeping them in water with a temperature of about 49 degrees for half an hour. Subsequently, the seeds must be cooled. It is also allowed to disinfect them with the TMTD preparation (for each kilogram of seeds - 3-4 g of the preparation).

At the first sign of the ill-fated septoria blight, celery is sprayed several times with one-percent Bordeaux liquid at an interval of ten days.

If during the growing season the disease attacks the vegetation with particular force, it will be advisable to treat the celery with such fungicides as Topsin, Fundazol or Ditan. But it is not recommended to treat leafy celery with fungicides.

Severely damaged vegetation should be removed from greenhouses or garden beds. And after harvesting, it is necessary to remove all plant residues.