c8.3.8 – Relationships between terpene composition and the attack of Heterobasidion annosum in Picea sitchensis

Woodward S (1), Martini V (2), Deflorio G (1), Capretti P (2), Michelozzi M* (3)

(1) University of Aberdeen, Institute of Biological and Environmental Sciences, Department of Plant and Soil Science, Cruickshank Building, St. Machar Drive, Aberdeen AB24 3UU, Scotland (UK); (2) Dipartimento di Biotecnologie Agrarie, Sez. Patologia vegetale, Università degli studi di Firenze, P.le delle Cascine 28, I-50144 Firenze (Italy); (3) Istituto di Genetica Vegetale, Consiglio Nazionale delle Ricerche, via Madonna del Piano 10, I-50019 Sesto Fiorentino (FI – Italy)
Collocazione: c8.3.8 – Tipo Comunicazione: Presentazione orale
8° Congresso SISEF *
Sessione 3: “Clima e Foreste: quali scenari di impatto, mitigazione e adattamento?” *

Contatto: Marco Michelozzi (marco.michelozzi@igv.cnr.it)

Abstract: Picea sitchensis (Bong.) Carr. (Sitka spruce) is the most important commercial timber species in United Kingdom, occupying 40% of the coniferous forest area. Sitka spruce trees as many other forest tree species, are very susceptible to the attack of Heterobasidion annosum (Fr.) Bref., a serious root and butt-rot fungal pathogen of conifers that causes significant economic losses when monoculture plantations are attacked. Spruce produces a vast array of secondary metabolites including terpenoids, some of which may help to repel attack by pests and pathogens. Variations occurring in the constitutive and induced terpene composition can provide defensive potential against pest and diseases. The aim of this study was to examine changes in terpene profiles of different 20 year old clones of P. sitchensis following inoculation with H. annosum. Terpene composition was analyzed in cortical tissue samples by gas chromatography–flame ionization detection (GC-FID) and enantiomeric monoterpenes were separated on a Cyclodex-B capillary column. β-phellandrene was the most abundant compound; (-)-α-pinene, (-)-β-pinene, sabinene and myrcene were major constituents, whereas ( )-α-pinene, ( )-β-pinene, (-)-limonene, ( )-limonene, γ-terpinene, terpinolene were minor components. Concentration of several terpenes increased following either wounding and wounding plus inoculation, The highest values in terpene content were detected in infected tissues 43 days after the inoculation. Systemic induction of a monoterpene effect was not observed 43 days after treatment. Our results showed that terpene metabolism is involved in chemical defence of P. sitchensis in response to attack by H. annosum and suggest the possibility to use terpenes as resistance markers for selection of less susceptible chemotypes to infection by this pathogenic fungus. Such results confirm previous results and make possible the utilization of terpenes as an aid in selecting for sitka spruce clones which could be less sensitive to H. annosum. Progeny testing, possibly including short- term artificial inoculation tests for resistance, would still be necessary to verify resistance in “relatively resistant” chemotypes.

Parole chiave: Sitka Spruce, Heterobasidion Annosum, Terpenoids, Resistance Markers

Citazione: Woodward S , Martini V , Deflorio G , Capretti P , Michelozzi M (2011). Relationships between terpene composition and the attack of Heterobasidion annosum in Picea sitchensis . 8° Congresso Nazionale SISEF, Rende (CS), 04 – 07 Ott 2011, Contributo no. #c8.3.8