Project: 1999-03. Report - Induced Resistance in Pinus radiata Against Fusarium circinatum
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Date: June, 2001 Author: T. Reglinski and M. A. Dick Publication: Forest Research Contract Report No. 8939 Project reference: 1999-03 Full report is available from: |
Executive summary:
We investigated the use of biocontrol methods to protect Pinus radiata seedlings against infection with Fusarium circinatum, the causal agent of pine pitch canker. The effectiveness of two elicitors and a biocontrol agent (BCA), separately and in combination, were compared with a fungicide and a water control. Seedlings that were treated with elicitor 2, elicitor2/BCA, elicitorl/BCA, and fungicide, before wound-inoculation with F. circinatum, developed significantly shorter lesions (25-35% reduction) than the controls. However, elicitor 1 and the BCA alone were not effective, possibly due to the high inoculum level used (ca. 7500 spores per wound). The relationship between inoculum level and elicitor 1 efficacy was further investigated. Elicitor 1 reduced disease incidence and severity on seedlings that were inoculated with 100 spores/wound. Over 70% of the treated seedlings exhibited no disease symptoms and, where infection was apparent, the average lesion length was reduced compared to the controls. However, there was no significant treatment effect at inoculum levels greater than 500 spores/wound suggesting that the induced resistance response may have been overwhelmed. Taken together our data indicate that elicitors can be used to induce resistance in P. radiata to pine pitch canker and that the level of control can be further improved by the incorporation of a BCA
Full report is available from:
Crop & Food Research
Private bag 4704
Christchurch
New Zealand
