Variation in carbon availability, defense chemistry and susceptibility to fungal invasion along the stems of mature trees
© 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.
| Veröffentlicht in: | The New phytologist. - 1979. - 197(2013), 2 vom: 17. Jan., Seite 586-594 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2013
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| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Monoterpenes Carbon 7440-44-0 Starch 9005-25-8 |
| Zusammenfassung: | © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust. If carbon (C) sinks withdraw carbohydrates as they are transported along tree stems, carbohydrate availability may depend on local sink strength and distance from sources. Defenses, including monoterpenes--a major component of resin--limit the invasibility of pines. Since carbohydrate reserves fund monoterpene synthesis, we hypothesized that monoterpene concentrations in pine stems would decrease from the crown to the lower stem, and susceptibility to fungal infection would increase. Here, we measured carbohydrate and monoterpene concentrations along the stems of lodgepole pine trees (Pinus contorta var. latifolia) before inoculating with a blue-stain fungus at different heights. After 6 wk, we assessed tree responses to fungal infection based on lesion length and carbohydrate mobilization. Concentrations of carbohydrates and monoterpenes in the phloem before inoculation decreased with distance from the crown, whereas lesion lengths after inoculation increased. However, trees mobilized sugars in response to fungal infection such that carbohydrate reserves near lesions were similar at all heights. Despite C mobilization, the lower stem was more vulnerable than the upper stem. Consistent with predictions based on sink-source relationships, vulnerability occurred where carbohydrates were less available, and likely resulted from C withdrawal by sinks higher in the supply chain |
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| Beschreibung: | Date Completed 21.05.2013 Date Revised 20.04.2021 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/nph.12019 |