A NEW test that detects the threat of the potato disease, spraing, could help reduce nematicide use, according to experts.

The diagnostic test developed by the Scottish Agricultural College (SAC) detects the presence in soil samples of the tobacco rattle virus (TRV), which causes spraing.

Faster and more conclusive detection of TRV means nematicide treatments can be better targeted and where there is no threat of spraing developing, unnecessary application can be prevented, researchers said.

This could have environmental benefits, as well as reducing costs for growers, the SAC said.

The service is available to growers for the 2005 season, with a one to three week turnaround from receiving soil samples to getting results back.

The test is offered on two levels (TRV Level 1 and 2), with a Level 1 test including a count of the number of nematodes in the soil, as well as testing for the presence for the TRV.

Soil samples should be taken from October to March, the SAC recommends.

Growers can arrange for soil samples be taken by their local SAC Advisory Office, or do them themselves and send them into the SAC, indicating which test is required.

Further information and contact details are available from www.sac.ac.uk .