English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Frost resistance and ice nucleation temperatures of leaves, from bud swelling until after full expansion, were measured in situ for five major woody timberline species with recently developed field freezing equipment. Frost resistance determined in situ on leaves of attached twigs was significantly higher than values determined on detached leaves in laboratory tests (e.g., the temperature at which incipient frost damage was observed (LT i ) was 1.2 °C higher for detached leaves than for attached leaves of  Picea abies  (L.) Karst.). Frost resistance of leaves of all species changed significantly during shoot expansion (e.g., changes of 7.2 and 11 °C for  Rhododendron ferrugineum  L. and  Larix decidua  Mill., respectively). Expanding leaves (between 0 and 60% of full expansion) were the most sensitive to frost, with LT i  values ranging from –3.4 °C in  R. ferrugineum  to –6.3 °C in  L. decidua . Among the studied species,  P. abies  and  R. ferrugineum  were the most frost sensitive throughout the shoot elongation period. In situ freezing patterns of leaves of attached twigs also differed from those of leaves of excised twigs. During leaf expansion, two distinct freezing exotherms were always registered in situ. The first freezing event (E1, high-temperature exotherm) was recorded at –1.5 ± 0.2 °C and reflected extracellular ice formation. Exposure of leaves to temperatures at which E1 occurred was, in all cases, noninjurious. The low-temperature exotherm (E2) mostly coincided with frost damage, except for some stages of leaf expansion in  R. ferrugineum  and  P. abies , indicating that in situ freezing exotherms were not accurate estimators of frost damage in these species.

Frost resistance and ice nucleation in leaves of five woody timberline species measured in situ during shoot expansion