Effects of environmental factors on the shoot development of Quercus petraea seedlings A methodological approach

• Published in: Forest ecology and management 1997-10, Vol.97 (2), p.119-131
• Main Authors: Chaar, H., Colin, F., Collet, C.
• Format: Article
• Language: English
• Subjects: Agricultural sciences; Life Sciences; Silviculture, forestry
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/S0378-1127(97)00093-5

The objective of this study was to determine if various morphological components of height growth were sensitive to environmental factors (i.e., grass root competition, frost and shading) and to see if these components could be used to quantify the effect of environmental stress on the height growth of sessile oak ( Quercus petraea Liebl.) seedlings. The following components were measured: number of flushes produced on the main stem, length of the growth unit (GU) developed during each flush, annual GU length, number of nodes per GU, and state of the terminal bud of each GU. The number of flushes produced was reduced by all environmental treatments. The annual GU length was positively related to the number of flushes produced. Grass competition reduced GU length in each flush and therefore reduced annual GU length. On the other hand, partial shading increased GU length in each flush and annual GU length. Number of nodes was not apparently affected by environmental factors and was positively related to GU length. Where factors that affect terminal bud mortality were partially controlled (i.e., in grass competition and shading experiments), mortality rate was low (5% for GUs of the first flush in grass competition experiment), but in the frost experiment terminal bud mortality rate was higher (64% for GUs of the first flush). The sensitivity of the different morphological components to environmental factors and the quantification of the effects of the factors using generalized linear models were discussed.