Hebe: aspects of the biology and control of fusarium wilt

In 2005, Fusarium oxysporum was consistently isolated from stained vascular tissue of container-grown hebe plants affected by wilt and dieback. A vascular wilt disease of hebe caused by F. oxysporum was first described in Europe in 2000 (in Italy) and it was considered that this might be the same problem. Hebe is a very popular garden plant and the occurrence of a new wilt disease could severely damage sales. By the start of this project, the problem had been recognised on one nursery, where it had been a continuing problem for several years. In 2005 it caused losses of over 15,000 plants.

Findings:

Fusarium wilt of hebe in the UK is caused by Fusarium oxysporum; the disease can be managed by varietal choice, maintaining stock plants free of F. oxysporum, fungicide drenches to the growing medium and disinfection of re-used containers and standing beds.

The objectives of this project were:

1. To determine whether oxysporum is a cause of hebe wilt in the UK;
2. To investigate aspects of the disease biology and spread;
3. To devise an effective control strategy.