Responses to temperature and shade in Abies alba seedlings from diverse provenances
Abstract:Intraspecific variability in responses to temperature and shade was studied at Champenoux, north-eastern France, with seedlings from five Polish provenances of silver fir ( Abies alba Mill.). Acclimation of photosynthesis to temperature was investigated in seedlings exposed to 10, 25 and 35°C in a climate chamber for 1 week. During two growth seasons, a population of seedlings was grown in the nursery under four different irradiance regimens: 100, 48, 18 and 8% of natural irradiance. Maximum carboxylation rate ( V cmax ), maximum light driven electron flow ( J max ) and maximum net carbon dioxide assimilation rate ( A max ) measured at 25°C increased with population altitude. One week of exposure to 35°C caused discoloration and massive needle shedding. After 2 years' acclimation to different levels of irradiance, a significant interprovenance variability was evidenced in growth, total biomass, biomass allocation and photosynthetic performance. This study provided evidence for the existence of functional variation among the examined provenances.
Document Type: Research Article
Affiliations: 1: Department of Forestry, August Cieszkowski Agricultural University of Poznan, Poznan, Poland 2: Unité Mixte de Recherches INRA-UHP “Ecologie et Ecophysiologie Forestières”, Champenoux, France
Publication date: 2005-12-01