Open access publications in the SLU publication database

Abstract

Results are presented from a study concerning the influence of environmental factors on the formation of summer shoots in young plants of Pinus silvestris L. grown in plastic green houses. A close relationship is found between the studied factors: CO2, water, nutrients and the occurrence of summer shoots. Poor environmental conditions during the first year followed by improved conditions in the following year resulted in a great number of plants with summer shoots, whereas favourable conditions during the first year resulted in a low number of plants with summer shoots the following year. According to these results the conclusion is drawn that environmental conditions and especially those of the preceding year have a great influence on the formation of summer shoots and on the shoot growth as well. As a hypothesis it is discussed that carbohydrates in the plant may influence the formation of summer shoots and that this influence is mediated by growth regulators.