Summary Drought is considered to enhance susceptibility of N orway spruce ( P icea abies ) infestations by the Eurasian bark beetle I ps typographus , C oleoptera: urculionidae), although empirical evidence scarce. We studied impact experimentally induced drought on tree water status and constitutive resin flow, how physiological stress affects host acceptance resistance. established rain‐out shelters induce both severe (two full‐cover plots) moderate semi‐cover stress. In total, 18 sample...

Summary Drought affects the complex interactions between Norway spruce, bark beetle Ips typographus and associated microorganisms. We investigated interplay of tree water status, defense carbohydrate reserves with incidence attack infection fungi in mature spruce trees. installed roofs to induce a 2‐yr moderate drought managed stand examine maximum 10 roof control trees for resin flow (RF), predawn twig potentials, terpene, phenolic concentrations, borings field bioassays before after...

Abstract Xylem embolism is a limiting factor for woody species worldwide. Conifers at the alpine timberline are exposed to drought and freeze-thaw stress during winter, which induce potentially lethal embolism. Previous studies indicated that trees survive by xylem refilling. In this study on Picea abies, refilling was monitored winter spring seasons analyzed in laboratory situ experiments, based hydraulic, anatomical, histochemical methods. Refilling started late when soil frozen water not...

Summary Wood structure differs widely among tree species and with faster growth, higher mortality larger maximum size have been reported to fewer but vessels hydraulic conductivity (Kh). However, previous studies compiled data from various sources, often failed control rarely controlled variation in other traits. We measured wood density, vessel traits for 325 a wet forest Panama, compared leaf demographic using species‐level phylogenetically independent contrasts. showed strong phylogenetic...

Genetic parameters were estimated for wood and growth traits in two 19-yr-old clonal trials a 40-yr-old full-sib progeny trial of Norway spruce [Picea abies (L.) Karst.]. In the high (>0.4) broad-sense heritabilities found density traits, lignin content, number internal cracks, spiral grain resin canals. Moderate (0.2–0.4) tracheid lumen diameter cell wall thickness, microfibril angle length, while low (<0.2) pulp yield, fibre strength, stiffness colour. Lignin content yield showed genetic...

Abstract Climate change‐related environmental stress has been recognized as a driving force in accelerating forest mortality over the last decades Central Europe. Here, we aim to elucidate thermal sensitivity of three native conifer species, namely Norway spruce ( Picea abies ), Scots pine Pinus sylvestris ) and silver fir Abies alba non‐native Austrian nigra Douglas Pseudotsuga menziesii Atlas cedar Cedrus atlantica ). Thermal sensitivity, defined here decline maximum quantum yield...

We linked hydraulic vulnerability in Norway spruce (Picea abies (L.) Karst.) trunkwood with different cambial age to wood density and applied the findings on annual variations healthy declining trees from southern during 1990 2010. hypothesized that drought stress due 2003 or 2006 European heat waves were triggers for tree decline focused analyses structure of was produced after, as well before, signs stress, i.e., when decreases height diameter growth visible. In data set comprising...

More frequently occurring, drought waves call for a deeper understanding of tree hydraulics and fast easily applicable methods to measure stress. The aim this study was establish empirical relationships between the percent loss hydraulic conductivity (PLC) relative water (RWL) in woody stem axes with different P 50 , i.e. potential (Ψ) that causes 50% loss. Branches saplings temperate conifer ( Picea abies Larix decidua ) angiosperm species Acer campestre Fagus sylvatica Populus x canescens...

• The aim of this study was to assess the hydraulic vulnerability Norway spruce (Picea abies) trunkwood by extraction selected features acoustic emissions (AEs) detected during dehydration standard size samples. method used as reference different cambial ages. Vulnerability curves were constructed plotting percentage loss conductivity vs an overpressure compressed air. Differences in very pronounced between juvenile and mature wood samples; therefore, useful AE features, such peak amplitude,...

Stem segments of eight five-year-old Norway spruce (Picea abies (L.) Karst.) clones differing in growth characteristics were tested for maximum specific hydraulic conductivity (ks100), vulnerability to cavitation and behavior under mechanical stress. The the was assessed by measuring applied air pressure required cause 12 50% loss (Ψ12, Ψ50) percent at 4 MPa (PLC4MPa). bending strength stiffness axial compression same stem measured characterize wood properties. Growth ring width, density,...

Ultrasonic emission (UE) testing is used to analyse the vulnerability of xylem embolism, but number UEs often does not sufficiently reflect effects on hydraulic conductivity. We monitored absolute energy UE signals in dehydrating samples hypothesizing that (i) conduit diameter correlated with and (ii) monitoring may enhance utility this technique for analysis vulnerability. Split were prepared from trunk wood Picea abies, four categories samples, derived mature (I: earlywood, II: 30–50%...

Top dieback in 40-60 years old forest stands of Norway spruce (Picea abies (L.) Karst.) southern is supposed to be associated with climatic extremes. Our intention was learn more about the processes related top and particular plasticity possible predisposing factors. We aimed at (i) developing proxies for P50 based on anatomical data assessed by SilviScan technology (ii) testing these their regarding climate, order (iii) analyze annual variations hydraulic healthy looking trees upon impact...

In this study, vulnerability to cavitation, P50 (i.e. the water potential causing 50 % loss of hydraulic conductivity), Norway spruce trunkwood at different cambial age was related wood density. Wood density calculated from mass in oven dry state either volume oven-dry (dry density) or full saturation (basic density). Dry and basic were strongly linearly (r² = 0.99); there however a shift 1:1 reference line with increasing as well had similar high predictive qualities for 0.85). The...

Hybrid saplings were more reactive to soil water deficit than Japanese and European larch. larch had hydraulically safer wood anisohydric behavior, hybrid showed isohydric strategy.Deciduous species could be an alternative evergreen conifers in reforestation, but little is known about drought sensitivity of their saplings. The effect experimental on hydraulics quantitative anatomy was tested (EL, Larix decidua), (JL, kaempferi) (HL). Across species, biomass, transpiration rate relative...

Introduction Drought-induced embolism formation in conifers is associated with several tracheid and pit traits, which vary parallel from stem apex to base. We tested whether this axial anatomical variability a progressive variation vulnerability along the Methods assessed hydraulic diameter ( Dh ), mean membrane area PMA ) xylem pressure at 50% loss of conductivity P50 on longitudinal segments extracted different distances DFA Picea abies an Abies alba tree. Results In both trees, scaled 0.2...

Climate change profoundly impacts the physiological processes and adaptation strategies of plants. However, mechanisms coniferous species responding adapting to combined drought nitrogen (N) addition remain unclear. Here, based on 2-year multi-level N experiments, we investigated responses carbon assimilation (net photosynthetic rate A n , stomatal conductance g s intrinsic water use efficiency WUE i ) reserves (non-structural carbohydrates, NSC) 7-year-old Korean pine ( Pinus koraiensis...

The aim of this study was to observe the radial shrinkage Norway spruce [Picea abies (L. Karst.)] trunkwood specimens with different hydraulic vulnerability cavitation from fully saturated state until overall reaches a stable value, and relate wood recovery cavitations water column inside tracheids. Radial processes in standard-size sapwood (6 mm × 6 100 mm; radial, tangential longitudinal) obtained at positions within trunk, representing ages cambium, were compared. Cavitation events...

Summary Acoustic emission ( AE ) analysis allows nondestructive monitoring of embolism formation in plant xylem, but signal interpretation and agreement acoustically measured hydraulic vulnerability with reference techniques remain under debate. We compared the 16 species three crop tree cultivars using flow measurements acoustic monitoring, proposing use time‐dependent rates as a novel parameter for analysis. There was linear correlation between water potential (Ψ) at 50% loss conductivity...