Effects of nitrogen fertilization and temperature on frost hardiness of Aleppo pine (Pinus halepensis Mill.) seedlings assessed by chlorophyll fluorescence
Authors: Puértolas, Jaime; Gil, Luis; Pardos, José Alberto
Source: Forestry, Volume 78, Number 5, December 2005 , pp. 501-511(11)
Publisher: Oxford University Press
Abstract:In a 14-week study, 1-year-old Aleppo pine seedlings were grown in two growth chambers. Seedlings were artificially hardened by decreasing photoperiod and temperature. In each chamber half of the seedlings were fertilized with nitrogen (8.4 mg seedling−1). In order to determine the relative importance of the hardening environment versus fertilization, each chamber was programmed to decrease night temperatures down to a low of 8 or 4°C. Chlorophyll fluorescence and frost hardiness was measured five times during the experiment. A sample of seedlings from each treatment was exposed to an artificial frost at −5°C and the freezing effects were assessed by measurements of chlorophyll fluorescence and visual evaluation of needle damage. Seedlings increased their frost hardiness during the experiment in all the treatments but the ratio of variable to maximal chlorophyll fluorescence (F
Document Type: Research Article
Publication date: December 2005
- Forestry publishes refereed papers on all aspects of research, practice and policy that promote the sustainable development of forests, woodlands and trees. In considering suitability for publication attention is given to both the originality of contributions and their practical application. Preference is usually given to work undertaken in the temperate and/or boreal zones; only articles of exceptional merit from tropical zones will also be considered.