We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Resource partitioning to growth, storage and defence in nitrogen-fertilized Scots pine and susceptibility of the seedlings to the tarnished plant bug Lygus rugulipennis.
- Authors
Holopainen, Jarmo K.; Rikala, Risto; Kainulainen, Pirjo; Oksanen, Jari
- Abstract
We tested how variable nitrogen availability affects the above- and below-ground growth of first-year Scots pine (Pinus sylvestris L.) seedlings and carbon allocation to defensive allelochemicals and storage. Concentrations of free amino acids were considered as indicators of nutritive quality. Suitability of seedlings for polyphagous Lygus rugulipennis Popp. (Heteroptera: Miridae) was tested with oviposition preference and nymphal growth experiments. At the end of the growing season, needle length increased while root biomass decreased with elevated N fertilization, but shoot length was not affected. Concentration of starch in needles and roots, representing carbon storage, was not significantly affected by N fertilization, although there was a decrease in the starch concentration of needles when nitrogen input increased. Nitrogen fertilization significantly increased the pool of total and non- essential amino acids in the shoots. Arginine, proline and glutamine were the individual amino acids most affected by elevated N. Of the carbon-based defence compounds, total resin acid concentrations in shoots were significantly reduced with elevated nitrogen in 9-wk-old seedlings. Palustric acid and neoabietic acid were the most affected individual resin acids, whereas foliar monoterpenes were nor influenced by N availability. Total phenolics in shoot and root showed variable response. The increasing effect of nitrogen on the oviposition rate of Lygus females was almost linear. Mean relative growth rate of the nymphs was significantly affected by the level of N fertilization, but the mortality of nymphs was high in all treatments. The results suggest that in nitrogen-rich environments the needle growth of small Scots pine seedlings is improved, but their susceptibility to insect attack is increased and they remain less defended as predicted by the carbon/nutrient balance hypothesis.
- Subjects
PLANT growth; SCOTS pine; INSECT-plant relationships; PLANT metabolism; SEEDLINGS; PLANT physiology
- Publication
New Phytologist, 1995, Vol 131, Issue 4, p521
- ISSN
0028-646X
- Publication type
Article
- DOI
10.1111/j.1469-8137.1995.tb03088.x