Exotic Pests
The Pest and Disease Information Service is on the lookout for exotic vine pests that are currently not believed to be present in WA. These diseases could devastate our agricultural industries. The pests include:
Black vine weevil
Otiorhynchus sulcatusc causes damage at the larval stage to the root system of young vines which can cause wilting and even death. Adults chew small notches in the edges of leaves. This weevil has a very wide host range including strawberries and cut flowers.
Grape phylloxera
Phylloxera, Daktulosphaira vitifoliae, is a very small, yellow insect that feeds on the roots, and sometimes the leaves, of grapevines. It can also move to the soil surface and up into the canopy and the fruit. Feeding by phylloxera can damage a susceptible grapevine’s root system to such an extent that the plant may die.
Fruit fly
Natal fruit fly, Ceratitis rosa, and Queensland fruit fly, Bactrocera tryoni, have females that pierce (sting) the maturing fruit and lay eggs just below the surface. Larvae emerge from the fruit to pupate in the soil.
Bacterial blight
The blight, Xanthomonas ampelina, is a bacterium that overwinters in the vines, emerges in spring and is carried to healthy shoots mainly by rain splash in autumn and winter. It appears as linear reddish-brown streaks extending from the base to the shoot tip; then, more or less lens-shaped cracks and cankers develop, sometimes as deep as the pith. Shoots subsequently wilt, droop and dry up.
Pierce’s disease
is caused by the grape strain of the bacterium Xylella fastidiosa. This grapevine disease is spread by sap (xylem) sucking insects. Affected vines tend to be smaller than healthy vines. Sensitive varieties show progressive decline, low yields (up to 80% losses), low fruit quality and a shortened productive life.