The angular leaf spot disease occurs particularly in fruit and vegetable plants. Once it is there, you should act quickly to prevent the disease from spreading to other plants. In this article you will find out the most important things about how it develops and how to combat it.
How do I combat square leaf spot?
Plants that suffer from square leaf spot shouldtake them completely out of the bed and dispose of them in organic waste. Do not compost under any circumstances to prevent transfer to other plants. For the same purpose, care tools, shoes, etc. must be thoroughly cleaned.
What characterizes angular leaf spot?
Angular leaf spot is characterized byangular leaf spots. These initially appear glassy and watery, but over time they become darker in color and acquire a light edge. As a result, the spots wither and become brittle. Eventually they die and actually break out, creatingleaf holes.
The fruits are not spared either. Round, cracked spots appear on them. These are initially green and later brown. In addition, the fruits shrink. Both the undersides of the leaves and the spots on the fruits are covered withbacterial slime.
On which plants does square leaf spot occur?
The square leaf spot disease occurs primarily on outdoor and greenhouse cucumbers. In addition, it can, for example,melons,pumpkinsandzucchinias well asstrawberrieshaunt.
Which pathogens cause angular leaf spot?
Square leaf spot is abacterial infection. The trigger is the bacteriumPseudomonas syringae pv. lachrymans.
The pests are extremely resistant. They survive for some time both in seeds and on diseased parts of plants in the soil. In spring they make their way into the plant tissue through stomata or small wounds, where they multiply and at the same time cause considerable damage.
Wind, rain, insects and care tools spread the bacteria to the already infected plant and to neighboring plants.
What factors promote angular leaf spot?
Daytime temperatures around 20 °C and cold nights combined with high humidity ormoist environment and persistent leaf wetness promote infection with angular leaf spot disease. Such conditions usually occur in spring when there is frequent rain or sprinkler irrigation is used.
How do I prevent square leaf spot?
To prevent square leaf spot on your plants, you should note the following points:
- When growing, use he althy young plants orperfect seeds.
- Always eliminate potential sources of infection such as dead leaves promptly.
- Organize the irrigation so that your plants candry quickly.
- Maintain an interval of at least three years before growing the respective crop again (keyword crop rotation).
- Care for all plants according to their needs.
Tip
Drying seeds before sowing
To ensure bacteria-free seeds, you can dress them in advance with garlic or warm water.
