Manage Alternaria leaf blotch & fruit spot

Written by   Orchard plant protection guide

Alternaria leaf blotch is characterised by irregular red–brown coloured lesions on the leaves.
The lesions might expand under favourable conditions, followed by yellowing of the leaves and then defoliation of the trees.

Leaf lesions often exhibit blackish-purple borders.
Alternaria leaf blotch is distinguished by the fact that in favourable weather conditions the blotches will continue to grow, and when the leaf is half covered by lesions, it will tend to drop prematurely from the tree.
Alternaria fruit spot
Alternaria fruit spot is characterised by small,   slightly sunken, light to medium brown spots appearing on the lenticels of the fruit, often surrounded by a black border.
Symptoms appear after warm weather and usually no earlier than 42 days before harvest.
Non-pesticide management
Due to the similarity of Alternaria leaf blotch and fruit spot symptoms to those caused by other problems (e.g. fungal diseases and physical damage), it is important to have symptoms assessed by an expert, especially if you are considering applying fungicides (or other treatments) to combat these symptoms.
Be particularly vigilant with apple varieties that are susceptible to Alternaria leaf blotch and fruit spot including Fuji, Gala, Pink Lady and Red Delicious.
The proposed management approach for Alternaria leaf blotch and fruit spot includes the removal or breakdown of leaf residue, in particular when leaf disease occurred in the previous season.

See this article in Tree Fruit Dec 2019

About this website

This website presents articles from the Tree Fruit magazine. 
Here you can find information about fruit growing under specific topics (found in the menu)
REGISTER - and you can read complete feature articles without interruption.

Like what we do?

We produce and distribute Tree Fruit magazine. 
AND we design and maintain this and other websites. 
Discover what we can do for you.
Contact us

FTM logoEmail

Our services

Fruit Tree Media provide a suite of services:
•Design (website, e-commerce, print)
•Writing (editorial, advertorial, testimonials)
•Photography (in the field or studio)

We understand crop production practices: horticulture and broad acre.
We can translate technical information into understandable, effective messages.
What we produce is 'earthy' and direct, but it is also modern and well designed.

See our website for more information or contact us.


Orchard Manuals

Orchard Manuals that help orchardists grow fruit profitably.

Latest orchard management, tree training and fruit production methods.

Easy to follow instructions, many illustrations and photos.
Available as PDF files—ready to download and print!

Find them here
or from our sister site:

Back to top