Terpenoids are characteristic constitutive and inducible defense chemicals of conifers. The biochemical regulation of terpene formation, accumulation, and release from conifer needles was studied in Norway spruce [Picea abies L. (Karst)] saplings using methyl jasmonate (MeJA) to induce defensive responses without inflicting physical damage to terpene storage structures. MeJA treatment caused a ...

Increasing drought periods as a result of global climate change pose a threat to many tree species by possibly outpacing their adaptive capabilities. Revealing the genetic basis of drought stress response is therefore implemental for future conservation strategies and risk assessment. Access to informative genomic regions is however challenging, especially for conifers, partially due to their l...

Annual estimates of defoliation are important tools for managing forest insect defoliators such as the hemlock looper, which feeds on conifer needles all age classes. We tested accuracy classes obtained from aerial surveys by comparing them with ground-based during a recent outbreak this insect. used an approach derived Fettes method to estimate current-year shoots well four previous years. Def...

The long-term harsh climate conditions in 2015 distorted already from June up to November in all study trees of Tsuga and Taxus the intracellular organization of the needles. Intimately involved in these repressive processes were the flavanols, a small subgroup of the flavonoids. They were not only deposited in vacuoles of conifer needles but also in the nuclei and chromosomes. Among the many f...

The anatomical structure of mesophyll tissue in the leaf is tightly connected with many physiological processes in plants. One of the most important mesophyll parameters related to photosynthesis is the internal leaf surface area, i.e. the surface area of mesophyll cell walls exposed to intercellular spaces. An efficient design-based stereological method can be applied for estimation of this pa...

The phloem vascular system facilitates transport of energy-rich sugar and signalling molecules in plants, thus permitting long-range communication within the organism and growth of non-photosynthesizing organs such as roots and fruits. The flow is driven by osmotic pressure, generated by differences in sugar concentration between distal parts of the plant. The phloem is an intricate distributio...

Abstract. Mercury, Hg, is one of the most problematic metals from an environmental perspective. To assess problems caused by Hg in environment, it crucial to understand processes biogeochemistry, but exchange between atmosphere and vegetation not sufficiently well characterized. We explored mercury concentration, [Hg], foliage a diverse set plant types, locations sampling periods study whether ...