Banana Freckle
Zeki Murad, Department of Primary Industries and Fisheries
What is it?
Freckle is a disease of banana leaves and fruit. It is caused by a fungus, which has two names, Phyllosticta musarum and Guignardia musae. This has occurred because the fungus produces two types of spores.
Severe infection results in yellowing of the leaf, which withers and dies.
Where is it now?
In Queensland, a form of freckle disease has been found on islands in Torres Strait and on Cape York Peninsula, but not in banana production areas. It has been seen on cooking bananas such as Bluggoe, but not on dessert bananas such as Cavendish and Lady Finger. Freckle also occurs on cooking bananas in Papua New Guinea, other areas of south-east Asia, and possibly India, the Caribbean and central Africa.
However in the Philippines and Taiwan (and possibly India, Borneo and Java), a form of freckle disease is also found on Cavendish bananas.
Freckle disease has been reported on Cavendish bananas in the Ord River production area of Western Australia but it has not been seen there for about twenty years. Freckle disease was recently reported on Cavendish bananas in a remote area of Western Australia.
What do I look for?
Large and small spots are found on leaves and also on fruit. The most characteristic symptom of both types of spot is a sandpaper feel to the leaf and fruit. This is caused by the fungal structures protruding through the surface of the leaf.
Both the large and small spots are dark brown to black in colour. The small spots are less than 1mm in diameter and appear sooty. They can run together to form streaks. The larger spots are up to 4mm in diameter and can also appear as streaks. Sometimes the centre of these larger spots are lighter in colour. Spots can also appear on the midrib of the leaf and on the petioles.
Large freckle spots visible on a dead banana leaf.
Spread of freckle on a leaf roughly concentrated on leaf veins.
Freckle spots concentrated on leaf lateral veins (above and below).
Freckle spots on Bluggoe fruit above.
How does it spread?
Reproductive spores are ascospores and conidia, with conidia playing an important role in infection. They are emitted from the leaf in wet weather and the water moves the spores as it runs across the leaves. This leads to the streaking.
What control options are there?
(Mancozeb, DMIs and Benomyl, which are used to control yellow Sigatoka, will provide effective control of Freckle. (Mineral oil alone is thought to be ineffective). The use of a plastic bag cover over the bunch may in the long run be the most economical control for freckle.
Who do I ring if I find the problem?
If you suspect that your plants have freckle contact the DPI&F Business Information Centre on 132523 immediately or your local Plant Health Officer at the nearest DPI&F Office.
Last updated 20 April 2005
