Crown reduction alleviates drought stress in sessile oak and Norway spruce seedlings

0572506 - ÚVGZ 2024 SI eng A - Abstract
Findurová, Hana - Opoku, Emmanuel - Bystřická, Lucie - Petrovičová, Lucia - Světlík, Jan - Klem, Karel
Crown reduction alleviates drought stress in sessile oak and Norway spruce seedlings.
Plants in Changing Environment. Ljubljana: Slovenian Society of Plant Biology, 2022 - (Baebler, Š.; Dermastia, M.; Grebenc, T.; Praprotnik, E.; Razinger, J.; Urbanek Krajnc, A.). s. 33-33. ISBN 978-961-91014-5-2.
[Plants in Changing Environment. 15.09.2022-16.09.2022, Ljubljana]
Institutional support: RVO:86652079
Keywords : sessile oak * norway spruce * drought * crown reduction * hydrogel
OECD category: Forestry
https://intra.czechglobe.cz/media/publications/PlantsInChangingEnvironment22AbstractBook.pdf

Seedling stage represents the most vulnerable phase in a life of a tree. When planting a forest, the newly planted tree seedlings are exposed to sudden changes in conditions, often including a lack of shading and drought stress. Drought stress frequency and intensity are, however, increasing due to climate change and are expected to further rise in the future. As a consequence, we can expect higher tree seedling mortality shortly after the planting. To explore the possibilities to improve seedling performance under drought stress, we compared the effect of two drought stress-protective treatments on seedlings of two tree species. Potted seedlings of sessile oak and Norway spruce were treated with hydrogel amended in the substrate, crown reduction, or their combination. Half of the seedlings were subsequently exposed to long-term drought stress maintained by reduced irrigation. The isohydric Norway spruce seedlings showed a higher stomatal conductance (gs) and transpiration rate (E) in the wet treatment than anisohydric sessile oak. The drought-treated spruce seedlings experienced a reduction both in gs and E while only minor differences caused by drought were recorded for oak. Similarly, the photosynthetic rate of spruce seedlings was more affected by drought treatment than in oak seedlings. While hydrogel amendment did not prove to be a sufficiently effective action against drought stress, crown reduction led to increased soil humidity and thus postponed the drought impacts. The drought-treated seedlings with reduced crown had higher both gs and photosynthetic rate than the corresponding treatment without crown reduction. This also indicates that seedlings with reduced crown are less prone to carbon starvation and should have a better survival rate under the drought stress. Crown reduction therefore might be an effective tool to alleviate the drought stress after seedling planting by postponing the soil drying and thus providing more time for plant establishment in a new habitat.
Permanent Link: https://hdl.handle.net/11104/0343166