Solar irradiation levels during simulated long- and short-term heat waves significantly influence heat survival, pigment and ascorbate composition, and free radical scavenging activity in alpine Vaccinium gaultherioides.

ABSTRACT: In the 20th century, annual mean temperatures in the European Alps rose by almost 1 K and are predicted to rise further, increasing the impact of temperature on alpine plants. The role of light in the heat hardening of plants is still not fully understood. Here, the alpine dwarf shrub Vaccinium gaultherioides was exposed in situ to controlled short-term heat spells (150 min with leaf temperatures 43-49°C) and long-term heat waves (7 days, 30°C) under different irradiation intensities. Lethal leaf temperatures (LT₅₀ ) were calculated. Low solar irradiation [max. 250 photosynthetic photon flux density (PPFD)] during short-term heat treatments mitigated the heat stress, shown by reduced leaf tissue damage and higher F_v /F_m (potential quantum efficiency of phot

SUBMITTER: Karadar M 

PROVIDER: S-EPMC6033156 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature