How to get rid of southern blight? How to control southern blight? First, find out about southern blight carrot symptoms and treatment guidelines!
Table of Contents
Southern Blight Carrot Definition
Southern blight carrot meaning – What is southern blight carrot?
Southern blight is important for many cultivated plants, including Apiaceae vegetables like carrot, celery, parsley, and parsnip. Its effects are worst in tropical and subtropical areas. However, southern blight isn’t a big deal in southern Europe, and it hasn’t spread to the UK yet.
Southern Blight Carrot Causes
What causes southern blight carrot? What is the most common cause of southern blight carrot?
Southern blight is caused by the pathogen Athelia rolfsii, which lives in the soil. This basidiomycete fungus is mostly found in the field in its anamorph stage, which is called Sclerotium rolfsii. It is not clear what role the basidiomycete stage plays in disease development. Sclerotium rolfsii has a lot of white mycelium, and the connections between the hyphae are made with clamps. The diagnostic sclerotia are round and tan to light brown. They are easy to grow in a lab. Some isolates can make basidiospores, which are white and 6–12 x 1.0–1.7 mμ in size.
Southern Blight Carrot Symptoms
Signs and symptoms of southern blight carrot – What are some symptoms of southern blight carrot?
If the leaves touch the soil, this pathogen can cause water-soaked lesions, which can cause the leaves to turn yellow and die. More important is direct infection of the carrot root, which causes the taproot to turn pale brown and soft. In the later stages of the disease, the woody center of the root may be pulled out of the ground, or the whole root may rot away, leaving a hole in the ground that is lined with mycelium and root tissue.
Mycelium grows on roots that have been infected and on the soil around them. Small, brown, spherical sclerotia (1–2 mm in diameter) can be seen on infected tissues and mycelia. When temperatures are just right (27–30º C), sclerotia are made in 5–6 days. When the mycelium grows through the soil and touches other plants, the disease moves from one plant to another.
Southern Blight Carrot Disease Cycle
The pathogen is soilborne and can persist as sclerotia in soil for a long time. The soil saprophyte S. rolfsii can colonize organic substrates. When the temperature rises above 15º C, disease arises. Acidic soils and wet weather favor the growth of diseases.
Southern Blight Carrot Treatment Guidelines
Treatment of southern blight carrot – What is the best treatment for southern blight carrot?
Implement crop rotation, albeit its effectiveness will be limited given the pathogen’s broad host range and soil-borne nature. It can be less damaging to grow vegetables in the cooler months. In general, fungicides and soil enhancements are not very effective. For high-value crops, soil fumigation and heat treatments can be efficient and possibly economical.
I hope you understand about southern blight carrot symptoms and treatment guidelines.