| Title: | Combined drought and bark beetle attacks deplete non-structural carbohydrates and promote death of mature pine trees |
| Author(s): | Erbilgin N; Zanganeh L; Klutsch JG; Chen SH; Zhao S; Ishangulyyeva G; Burr SJ; Gaylord M; Hofstetter R; Keefover-Ring K; Raffa KF; Kolb T; |
| Address: | "Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada. Department of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Department of Forestry, New Mexico Highlands University, Las Vegas, New Mexico, USA. Forest Health Protection, USDA Forest Service, Milwaukee, Wisconsin, USA. Forest Health Protection, USDA Forest Service, Flagstaff, Arizona, USA. School of Forestry, Northern Arizona University, Flagstaff, Arizona, USA. Departments of Botany and Geography, University of Wisconsin-Madison, Madison, Wisconsin, USA. Department of Entomology, University of Wisconsin-Madison, Madison, Wisconsin, USA" |
| ISSN/ISBN: | 1365-3040 (Electronic) 0140-7791 (Linking) |
| Abstract: | "How carbohydrate reserves in conifers respond to drought and bark beetle attacks are poorly understood. We investigated changes in carbohydrate reserves and carbon-dependent diterpene defences in ponderosa pine trees that were experimentally subjected to two levels of drought stress (via root trenching) and two types of biotic challenge treatments (pheromone-induced bark beetle attacks or inoculations with crushed beetles that include beetle-associated fungi) for two consecutive years. Our results showed that trenching did not influence carbohydrates, whereas both biotic challenges reduced amounts of starch and sugars of trees. However, only the combined trenched-bark beetle attacked trees depleted carbohydrates and died during the first year of attacks. While live trees contained higher carbohydrates than dying trees, amounts of constitutive and induced diterpenes produced did not vary between live and beetle-attacked dying trees, respectively. Based on these results we propose that reallocation of carbohydrates to diterpenes during the early stages of beetle attacks is limited in drought-stricken trees, and that the combination of biotic and abiotic stress leads to tree death. The process of tree death is subsequently aggravated by beetle girdling of phloem, occlusion of vascular tissue by bark beetle-vectored fungi, and potential exploitation of host carbohydrates by bark beetle symbionts as nutrients" |
| Keywords: | Animals *Carbohydrate Metabolism *Droughts *Food Chain *Longevity Pinus ponderosa/*physiology Weevils/*physiology Dendroctonus spp.Pinus ponderosa diterpene resin acids soluble sugars starch tree increment cores; |
| Notes: | "MedlineErbilgin, Nadir Zanganeh, Leila Klutsch, Jennifer G Chen, Shih-Hsuan Zhao, Shiyang Ishangulyyeva, Guncha Burr, Stephen J Gaylord, Monica Hofstetter, Richard Keefover-Ring, Ken Raffa, Kenneth F Kolb, Thomas eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2021/10/07 Plant Cell Environ. 2021 Dec; 44(12):3636-3651. doi: 10.1111/pce.14197. Epub 2021 Oct 20" |
