Mango malformation disease

Have you seen mango malformation disease?

Be on the lookout for these symptoms and report them to Biosecurity Queensland on 13 25 23.

Early detection and reporting of symptoms are the key elements in controlling the pest.

Do not move any plant material off your property-this can spread the disease.

  • MMD distorted leaf bud
    MMD distorted leaf bud
  • Normal leaf bud
    Normal leaf bud
  • MMD distorted flower panicle
    MMD distorted flower panicle
  • Normal flower panicle
    Normal flower panicle

General information

Mango malformation disease (MMD) is a fungal disease of mango. It occurs throughout many mango-production areas in the world. Mango malformation disease causes abnormal flower and leaf development, resulting in reduced plant growth and fruit yield.

Mango (Mangifera indica) is the only known host of mango malformation disease.

Mango malformation disease is declared as a notifiable pest regulated under the Plant Protection Act 1989. This means that property owners are obliged to report suspect cases of mango malformation disease.

Mango malformation has been detected in isolated incidents in Queensland since 2009 and the Northern Territory since 2007. Each time, all the symptomatic trees were removed and destroyed with follow-up surveillance revealing no further infections.

Be on the lookout for symptoms and immediately report them to Biosecurity Queensland. Do not move any plant material off your property as this can spread the disease.

Call Biosecurity Queensland on 13 25 23 or the Exotic Plant Pest Hotline on 1800 084 881.

Overview

What causes MMD?

Mango malformation disease is caused by specific species of the fungus Fusarium.

Symptoms and damage

Abnormal, compact development of shoots and flowers are common signs of mango malformation disease. Both normal growth and mango malformation disease-affected growth may be present on a plant at the same time.

Shoots
Growing points such as leaf and stem buds produce misshapen shoots with short internodes and brittle leaves. The leaves are significantly smaller than those of healthy plants and re-curve towards the stem giving a squat, bunchy-top appearance.

Shoot damage occurs in mature trees but symptoms are particularly serious for young plants, which become severely stunted.

Flowers
Affected flower stems or panicles are thickened and highly branched, producing up to three times the normal number of flowers.

The flowers are enlarged, sterile and do not bear fruit. There are often high numbers of male flowers compared with perfect flowers. Panicles may also form dwarfed and distorted leaves instead of flowers.

Mango fruit
There are no impacts on human health from mango malformation disease and mango fruit is safe to eat.

Protecting your property from MMD

To avoid introducing mango malformation disease on to your property, establish new plantings with pest-free nursery stock. Grafting or marcot material should never be taken from an infected orchard. Nurseries should not be established in orchards affected by mango malformation disease.

Thorough cleaning of pruning equipment between trees reduces the spread of pests and disease.

Make sure that you and your farm workers are familiar with mango malformation disease symptoms and other mango pests.

Ensure that workers, visitors, vehicles and equipment are decontaminated before they enter and leave your farm.

Further information

Last updated 18 April 2013