© 2004 Heron Publishing—Victoria, Canada
Growth, allocation and tissue chemistry of Picea abies seedlings affected by nutrient supply during the second growing season
Seija Kaakinen (1, 2, 3), Annika Jolkkonen (1), Sari Iivonen (1) and Elina Vapaavuori (1)
1. The Finnish Forest Research Institute, Suonenjoki Research Station, FIN-77600 Suonenjoki, Finland / 2. Corresponding author (seija.kaakinen@metla.fi) / 3. Formerly Anttonen / Received November 26, 2002; accepted August 25, 2003; published online April 1, 2004
Summary
One-year-old Norway spruce (Picea abies (L.) Karst.) seedlings were grown hydroponically in a growth chamber to investigate the effects of low and high nutrient
availability (LN; 0.25 mM N and HN; 2.50 mM N) on growth, biomass allocation and chemical composition of needles, stem and
roots during the second growing season. Climatic conditions in the growth chamber simulated the mean growing season from May
to early October in Flakaliden, northern Sweden. In the latter half of the growing season, biomass allocation changed in response
to nutrient availability: increased root growth and decreased shoot growth led to higher root/shoot ratios in LN seedlings
than in HN seedlings. At high nutrient availability, total biomass, especially stem biomass, increased, as did total nonstructural
carbohydrate and nitrogen contents per seedling. Responses of stem chemistry to nutrient addition differed from those of adult
trees of the same provenance. In HN seedlings, concentrations of α-cellulose, hemicellulose and lignin decreased in the secondary
xylem. Our results illustrate the significance of retranslocation of stored nutrients to support new growth early in the season
when root growth and nutrient uptake are still low. We conclude that nutrient availability alters allocation patterns, thereby
influencing the success of 2-year-old Norway spruce seedlings at forest planting sites.
Keywords:
biomass, cellulose, chemical composition, hydroponic culture, lignin, Norway spruce.
