13 resultaten
Photosynthesis and respiration are major components of the plant carbon balance. During stress, like drought, carbohydrate supply from photosynthesis is reduced and the Krebs cycle respiration must be fueled with other stored carbon compounds. However, the dynamics of storage use are still unknown.
Volatile organic compounds (VOC) play important roles in atmospheric chemistry, plant ecology, and physiology, and biogenic VOC (BVOC) emitted by plants is the largest VOC source. Our knowledge about how environmental drivers (e.g., carbon, light, and temperature) may regulate BVOC emissions is
The acidity of peat-based substrates used in forest nurseries limits seedling mineral nutrition and growth as well as the activity of microorganisms. To our knowledge, no study has yet evaluated the use of granular calcite as a covering material to increase pH, calcium and CO2
Induced (traumatic) resin in white spruce (Picea glauca (Moench) Voss) leaders resistant or susceptible to the white pine weevil (Pissodes strobi Peck) was analyzed for volatile terpenes and diterpene resin acids after simulated white pine weevil damage. Leaders from 331 trees were wounded just
Carbon replicas and scanning electron micrographs of wax outgrowths on some leaf surfaces have not shown conclusively whether the outgrowths are tubes or solid rods. Some workers have suggested that they are solid rods. We find that negative stains will penetrate into a cavity in the centre of wax
Ozone (O(3)) flux into Norway spruce (Picea abies) and cembran pine (Pinus cembra) needles was estimated under ambient conditions at six rural sites between 580 and 1950 m a.s.l. We also assessed age-related differences in O(3) flux by examining changes in leaf conductance across the life span of
Polysaccharides were located in the walls of normal and compression wood tracheids of Pinus radiata (radiata pine), Picea sitchensis (Sitka spruce) and Picea abies (Norway spruce) by transmission electron microscopy using immunogold labelling with monoclonal antibodies to (1-->4)-beta-galactan
The developmental pathway of somatic embryogenesis in Norway spruce involves proliferation of proembryogenic masses (PEMs), PEM-to-somatic embryo transition and further development of the somatic embryos. It has previously been shown that extracellular signal molecules, including arabinogalactan
Evidence is presented for the first time that chemolithoautotrophic ammonia oxidizers (CAO) and chemolithoautotrophic nitrite oxidizers (CNO) colonize in appreciable cell numbers the phyllosphere of spruce trees in a forest ecosystem exposed for decades to high levels of atmospheric nitrogen (The
OBJECTIVE
Ozone is the most important air pollutant in Europe for forest ecosystems and the increase in the last decades is significant. The ozone impact on forests can be calculated and mapped based on the provisional European Critical Level (AOT40 = accumulated exposure over a threshold of 40 ppb,
We used an atomic force microscope to image cell wall isolated from needles of Serbian spruce tree and that synthesized from cell wall components. We also observed the structure of lignin model polymer (DHP), as a best substitute for the natural lignin. A tendency of aggregate formation was observed
RATIONALE
The stable isotope compositions of hydrogen and oxygen in water (δ
2 H and δ
18 O values) have been widely used to investigate plant water sources, but traditional isotopic measurements of plant waters are expensive and labor intensive. Recent work
Background: Freezing resistant plant organs are capable to manage ice formation, ice propagation, and ice accommodation down to variable temperature limits without damage. Insights in ice management strategies are essential for the