Onion Rust is caused by a fungus Puccinia allii. It is uncommon & rarely
causes significant damage to onions in the UK, unless it is being grown
next to an infected garlic crop.
SYMPTOMS
Small, reddish to dull orange, yellowy, oval-shaped spots and blotches
(pustules) develop on the leaves. They produce reddish airborne spores
in a powdery mass. These turn black later in the season. The pustules
enlarge to form a girdle around the leaves or seed heads. All plant
tissue above the girdle turns yellow and dies. If the infection is
severe, the size and quality of the onion will be reduced.
PREVENTION
* Destroy volunteer onion, garlic and leek plants – that is any not
planted in the garden that have grown on waste ground etc..
* Do not grow onions on land affected by rust in the previous
season, because onion rust overwinters on garlic and volunteer
Allium crops
* Grow varieties resistant to onion rust
TREATMENT
* Remove and burn diseased leaves
* Apply fungicides if a lot of pustules develop on the plants.
Follow the instructions on the label.
No related posts.
Related posts brought to you by Yet Another Related Posts Plugin.
