Nematodes are microscopic, worm-like organisms that live in soil. They attack roots of susceptible crops, leading to poor health, reduced productivity and even death. Four groups of nematodes damage grapevines:

• root-knot nematode (Meloidogyne spp.)
• root lesion nematode (Pratylenchus spp.)
• citrus nematode (Tylenchulus spp.)
• dagger nematode (Xiphinema spp.)

The root-knot nematode is the biggest problem in vineyards and can cause substantial economic loss. Nematodes are widely distributed in most Queensland soils and are particularly prevalent in the sandy soils of the Granite Belt. They are often present in re-plant sites following previous vineyards or other susceptible crops, especially tomatoes. You are likely to have nematodes present if planting a vineyard on land previously used for agriculture. The density of nematode populations correlates with the potential extent of economic loss.

If nematodes are present or are introduced into a vineyard and are left untreated, their numbers will tend to increase by infesting vines and susceptible weeds. DPI&F recommends the use of nematode tolerant rootstocks for all Queensland vineyards because nematodes are widespread in the state´s soils and they are difficult to control in established vineyards.