PESTS AND DISEASES OF FORESTRY IN NEW ZEALAND
Hainesia lythri, fungus disease of Eucalyptus seedlings
New Eucalyptus fungus in nurseries
From Forest Health News No.43, June 1995
Samples of Eucalyptus regnans and E. nitens leaves collected from nurseries in the Bay of Plenty by Colin Barr had a leafspot previously unseen in this laboratory. The leafspots were confined to the older leaves at the base of seedlings and were not having any apparent detrimental effect on plant growth. The causal agent of the light brown, often concentrically ringed, spreading blotch was identified as Hainesia lythri. This is the first confirmed record of this fungus from New Zealand.
Hainesia lythri has been recorded on a variety of hosts from Europe, Africa, Asia and Australia. It is reported to have caused severe damage to a wide range of Eucalyptus species growing in South African nurseries. In young seedlings the leafspots spread on to the stems and result in their death. In older plants the fungus was confined to the leaves. From subsequent inoculation tests it was concluded that H. lythri was a wound pathogen commonly associated with fertiliser burn to the leaves when combined with overhead irrigation. For this reason it is considered unlikely to be a serious problem in New Zealand nurseries. (Kiryn Dobbie, FRI)
