c2.5.4 – Variabilità e funzioni di difesa di profili terpenici in Pinaceae

Michelozzi M

IMGPF – CNR, v. Atto Vannucci 13, I-50134 Firenze (FI)
Collocazione: c2.5.4 – Tipo Comunicazione: Presentazione orale
2° Congresso SISEF *
Sessione 5: “Metabolismo secondario e fattori di stress: dagli indicatori alle strategie di mitigazione” *

Abstract: Terpenoids are the main components of the constitutive (primary resin) and induced (secondary resin) defences in pines against herbivores. About half of the resin produced by conifer species is composed by monoterpenes, and the other half by diterpenes, while sesquiterpenes occur in small amounts. Terpenes are under strong genetic control and analyses of monoterpenes offer great opportunities for selection of less susceptible chemotypes to pest and diseases. Significance of constitutive and induced terpenoid defences in conifer resistance is briefly presented. Discussion is focused on the relationships between constitutive monoterpene profiles and rust resistance caused by Cronartium quercuum (Berk.) Miyabe ex Shirai f. sp. fusiforme. in slash pine (Pinus elliottii Engelm. var. elliottii), loblolly pine (Pinus taeda L.) clones and jack pine families (Pinus banksiana Lamb.) of known level of resistance. Monoterpene composition in cortical samples was determined by means of headspace gas chromatography (HS-GC). Variance analyses were performed on the arcsin transformed monoterpene percentages. Results were consistent across species and showed that trees characterised by certain monoterpene combinations tended to be less susceptible than other chemotypes. Our investigations clearly showed the usefulness of monoterpene markers as an aid in selecting pines for resistance to rust.

Citazione: Michelozzi M (1999). Variabilità e funzioni di difesa di profili terpenici in Pinaceae . 2° Congresso Nazionale SISEF, Bologna, 20 – 22 Ott 1999, Contributo no. #c2.5.4