Wounding of Norway spruce by inoculation with sterile agar, or agar containing the pathogenic fungus Ceratocystis polonica, induced traumatic resin duct formation in stem. Visible anatomical responses occurred cambium 6-9 d post-inoculation. Near site cellular proliferation, polyphenolic accumulation, and lignification were as a wound reaction to seal damaged area. Five centimetres from cells cambial zone swelled divided form clusters. By 18 post-inoculation, these began differentiate into...

ABSTRACT The temperature during maternal reproduction affects adaptive traits in progenies of Norway spruce ( Picea abies (L) Karst.). Seed production a cold environment advances bud set and acclimation the autumn dehardening flushing spring, whereas warm reproductive delays timing these traits. We repeated crosses between same parents produced seeds under contrasting temperatures. Elevated temperatures were applied at different time points from female meiosis to embryogenesis, followed by...

To study the effect of chemical pretreatment on conifer resistance, 13-year-old Norway spruce (Picea abies (L.) Karst.) trees were treated with methyl jasmonate (MJ) or oxalic acid (OxA) outer bark and inoculated pathogenic blue-stain fungus Ceratocystis polonica (Siem.) C. Moreau 4 weeks later. Both chemicals significantly reduced symptoms fungal infection, but MJ was more effective than OxA (51 versus 18% reduction in length necrotic lesions phloem relative to untreated control trees)....

Polyphenolic parenchyma cells (PP cells) in Norway spruce (Picea abies (L.) Karst.) stem phloem play important roles constitutive and inducible defenses. To determine whether anatomical molecular changes PP are correlated with tree resistance, we infected two clones the pathogenic fungus Ceratocystis polonica (Siem.) C. Moreau. The induced significantly different lesion lengths clones, indicating that one clone was more resistant to (short lesions) than other (long lesions). After infection,...

Summary High biodiversity is regarded as a barrier against biological invasions. We hypothesized that the invasion success of pathogenic ascomycete Hymenoscyphus fraxineus threatening common ash in Europe relates to differences dispersal and colonization between invader diverse native competitors. Ash leaf mycobiome was monitored by high‐throughput sequencing fungal internal transcribed spacer region ( ITS ) quantitative PCR profiling H. DNA . Initiation ascospore production after...

Abstract Purpose of Review Forestry in northern temperate and boreal regions relies heavily on conifers. Rapid climate change associated increases adverse growing conditions predispose conifers to pathogens pests. The much longer generation time presumably, therefore, lower adaptive capacity relative their native or non-native biotic stressors may have devastating consequences. We provide an updated overview conifer defences underlying pathogen pest resistance discuss how defence traits can...

Abstract Norway spruce ( Picea abies ) bark contains specialized phloem parenchyma cells that swell and change their contents upon attack by the beetle Ips typographus its microbial associate, blue stain fungus Ceratocystis polonica . These exhibit bright autofluorescence after treatment with standard aldehyde fixatives, so have been postulated to contain phenolic compounds. Laser microdissection of sections combined cryogenic NMR spectroscopy demonstrated significantly higher concentrations...

Drought-induced mortality is a major direct effect of climate change on tree health, but drought can also affect trees indirectly by altering their susceptibility to pathogens. Here, we report how combination mild or severe and pathogen infection affected the growth, resistance gene expression in potted 5-year-old Norway spruce [Picea abies (L.) Karst.]. After 5 weeks drought, were inoculated with fungal Endoconidiophora polonica. Combined drought-pathogen stress over next 8 led significant...

Seedlings of Norway spruce were exposed to fungal infection and drought in order investigate differences their stress responses on the enzymatic level. Six-week-old seedlings infected with root rot fungus Rhizoctonia, or subjected drought, respectively. Changes at level more rapid significantly higher plants comparison drought-stressed plants. Rhizoctonia resulted early local systemic increase peroxidase chitinase activity. The most prominent isoforms responding highly basic peroxidases...

European ash (Fraxinus excelsior) is threatened by the invasive ascomycete Hymenoscyphus fraxineus originating from Asia. Ash leaf tissues serve as a route for shoot infection but also sporulation substrate this pathogen. Knowledge of niche partitioning indigenous fungi and H. needed to understand fungal community receptiveness invasion. We subjected DNA extracted unwashed washed leaflets healthy diseased PacBio sequencing ITS1-5.8S-ITS2 rDNA region. Leaflets co-inhabiting rowan trees...

Conifers and other trees are constantly adapting to changes in light conditions, water/nutrient supply temperatures by physiological morphological modifications of their foliage. However, the relationship between processes anatomical characteristics foliage has been little explored trees. In this study we evaluated needle structure function Norway spruce families exposed different conditions transpiration regimes. We compared sun-exposed shaded current-year needles a control plot thinned...

• Aluminium (Al) stress reduces plant growth. However, some species such as Norway spruce (Picea abies) seem to tolerate high Al concentrations. The aim of this study was investigate characteristics possibly involved in tolerance seedlings. Seedlings (10-d-old) were exposed Al3+ concentrations 0.5 and 5 mm for up 168 h. effect on root growth, cell morphology distribution, callose production, peroxidase chitinase activity analysed. Root growth decreased after 1 d 2 with Al, respectively....

We investigated the cellular responses of stem tissues mature Scots pine (Pinus sylvestris L.) trees to inoculations with two fungal pathogens. The bark beetle vectored fungus, Leptographium wingfieldii Morelet, induced longer lesions in bark, stronger swelling polyphenolic parenchyma cells, more polyphenol accumulation and increased ray activity compared root rot Heterobasidion annosum (Fr.) Bref., or mechanical wounding. Axial resin ducts xylem are a general feature preformed defenses...

Two mature clones of Norway spruce (Picea abies (L.) Karst.) that have previously been shown to differential degrees resistance towards the necrotrophic pathogen Heterobasidion parviporum (Niemelä & Korhonen) were compared with respect primed defense expression transcripts related biosynthesis lignin, stilbenes and other phenolic compounds from one year next. The host's response physical wounding inoculation was examined in initial year, whereas indications heightened basal level or...

In Norway spruce, a fungistatic reaction zone with high pH and enrichment of phenolics is formed in the sapwood facing heartwood colonized by white-rot fungus Heterobasidion parviporum. Fungal penetration eventually results expansion this xylem defense. To obtain information about mechanisms operating upon colonization pathogen, hyphal growth wood degradation were investigated using real-time PCR, microscopy, comparative density analysis naturally trees extensive stem decay. The hyphae...

Abstract Predicted increases in the frequency and duration of drought are expected to negatively affect tree vitality, but we know little about how water shortage will influence needle anatomy thereby trees’ photosynthetic hydraulic capacity. In this study, evaluated anatomical changes sun shade needles 20‐year‐old Norway spruce trees exposed artificial stress. Canopy position was found be important for structure, as had significantly higher values than all traits (i.e., cross‐sectional...

Abstract Modified wood can provide protection against a range of deteriorating organisms. Several hypotheses have been put forward regarding the mechanisms decaying fungi including fungal enzyme inefficiency due to non-recognition, lower micropore size, and insufficient moisture content. The aim this study was obtain new insight into manner furfuryl alcohol (FA) modified Scots pine sapwood (W FA ), examine biochemical adaptive changes in gene expression utilised by Postia placenta during...

Pathogen challenge of tree sapwood induces the formation reaction zones with antimicrobial properties such as elevated pH and cation content. Many fungi lower substrate by secreting oxalic acid, its conjugate base oxalate being a reductant well chelating agent for cations. To examine role acid in pathogenicity white-rot fungi, we conducted spatial quantification oxalate, transcript levels related fungal genes, element concentrations heartwood Norway spruce challenged naturally Heterobasidion...