Soilborne Plant Diseases
Soilborne diseases of the plants are usually those that are accumulated in the soil and can’t be detected until the plant starts to get sick and dies. These diseases are usually caused by microorganisms such as fungi that live in the soil and silently eat away the plant. Find out more about the soilborne disease, their causes and types.
Soilborne Disease Basics
Pear Leaf With Dark Spots
As with any disease there is a microscopic reason to that. A soilborne disease is usually a pathogen that causes the disease, then there is a host, which is the plant and there are conditions that allow the pathogen to thrive. The pathogens vary greatly: some like damp conditions, while others prefer dry conditions. The pathogens can live in the soil for many years before they start to show any signs of life and attack the plant.
Among the most common pathogens are:
- Fungi with over 8000 species that are harmful for the plants. The most common types are Cylindrocladium, Pythium, Phytophthora and Rhizoctonia.
- Bacteria is among the less common pathogena, like Erwinia (soft rot), Rhizomonas (corky root of lettuce), Streptomyces (potato scab, soft rot of sweet potatoes)
- Viruses are extremely rare and they are good in hiding. They can ride on fungi and nematodes to affect more plants. One of the examples is the lettuce necrotic stunt virus that affects Romaine lettuce plants.
- Nematodes – also called roundworms, can be parasitic or feed on root crops, the latter causing much more trouble.
Among the symptoms of a soilborne disease is the yellowing of leaves and dark spots, decaying root system and wilting. It is very important to identify the source of the soilborne disease, but if you are experiencing trouble with that, try contacting the local cooperative extension.