DISEASE

NAME
Woodiness of Passionfruit
Various Woodiness Viruses


Description
This is a viral problem that interferes with the production of chlorophyll and involves several viruses including passionfruit woodiness virus and cucumber mosaic virus.

Symptoms
The leaves become chlorotic and mottled growing smaller and may be deformed. The stems are stunted with closer internodes and the fruit skin becomes thick with a smaller pulp cavity resulting in poor quality. The overall effect on the plant results in lack of vigour and a reduction in fruiting life.

Fruit interior

Source and Dispersal
It is found on other infected plants and is dispersed by aphids particularly the green peach aphid.

Favoured Conditions
The symptoms are more prevalent on plants that are grown in cool climates, with plants grown in warm climates not showing symptoms.
     
Affected Plants
All passionfruit species and some legumes are effected by the passionfruit woodiness virus. The cucumber mosaic virus affects a large number of plants including weed species.

Non-chemical Control
It is difficult to control the spread of the virus as control of the aphids is required. Cultural methods such as selecting a warm site that is protected from cold winds and avoiding pruning during cooler weather can assist in control. Infested plants should be removed and destroyed and replanting new stock every 3 to 5 years is recommended.

Chemical Control
There is no satisfactory chemical control of viruses, but control of the aphids will reduce infestation.