Publications by authors named "Hammerbacher A"

Novel species of fungi described in this study include those from various countries as follows: , from accumulated snow sediment sample. , on leaf spots of . , on submerged decaying wood in sea water, on , as endophyte from healthy leaves of .

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Plant-microbe interactions significantly influence plant growth dynamics and adaptability. This study explores the impact of metabolites on microbial biodiversity in shoot tips and wood of Populus nigra under greenhouse conditions, using high-throughput sequencing and metabolite profiling. Branches from P.

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Eucalyptus spp. in plantations are negatively affected by canker and wilt diseases caused by several species of Ceratocystis, particularly those in the Latin American Clade (LAC). Ceratocystis eucalypticola and Ceratocystis manginecans are of particular concern where disease epidemics are reported globally, with recent outbreaks emerging in South African and Indonesian Eucalyptus plantations.

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Leaf epicuticular waxes provide important anatomical and chemical defences against fungi that infect leaves. In this study we analysed the leaf wax composition of Eucalyptus grandis × Eucalyptus urophylla hybrids with contrasting susceptibilities to Teratosphaeria leaf blight (TLB) caused by Teratosphaeria destructans, one of the most important foliar diseases of Eucalyptus. The Eucalyptus cuticular wax was extracted from non-inoculated and inoculated genotypes with different levels of susceptibility to TLB and analysed by gas chromatography-mass spectrometry.

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Novel species of fungi described in this study include those from various countries as follows: , on whitefly, on bark of , from soil under , on leaf spot of , and on leaf spot of . , on fully submersed siliceous schist in high-mountain streams, and on the lower part and apothecial discs of on a twig. , on decaying wood, from moist soil with leaf litter, on a trunk of a living unknown hardwood tree species, and on dead twigs of unidentified plant.

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TBCF10839 is a highly virulent strain that can persist and replicate in human neutrophils. Screening of a signature-tagged mutagenesis (STM) TBCF10839 transposon library in phagocytosis tests identified a mutant that carried the transposon in the VirB4 homolog 5PG21 of an integrative and conjugative element (ICE)-associated type IV secretion system of the pKLC102 subtype. 5P21 TBCF10839 insertion mutants were deficient in metabolic versatility, secretion, quorum sensing, and virulence.

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Outbreaks of the Eurasian spruce bark beetle (Ips typographus) have decimated millions of hectares of conifer forests in Europe in recent years. The ability of these 4.0 to 5.

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is an economically important pathogen of pine and resides in the species complex. Here we investigated the molecular processes underlying growth in by exploring the association between growth and the nutritional environment provided by the pine host. For this purpose, we subjected a mapping population consisting of X hybrid progeny to an analysis of growth rate on a pine-tissue derived medium.

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Shoot and leaf blight caused by is one of the most devastating foliar diseases on . Therefore, breeding for resistance to this disease is considered urgent. Differences in susceptibility to have been observed in the field but a robust inoculation protocol has, until recently, been unavailable and a disease scoring method for precise phenotyping has not been established.

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Globally, various species and hybrids of are of horticultural importance. In January 2022, we visited a private orchidarium near Pretoria (25° 54' 30" S, 28° 24' 34" E). During this visit, the owner reported mortality among various pure and hybrid and , an indigenous South African ornamental orchid.

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Terpenes and phenolics are important constitutive and inducible conifer defenses against bark beetles and their associated fungi. In this study, the inducible defenses of mature Norway spruce () trees with different histories of attack by the spruce bark beetle, were tested by inoculation with the -associated fungus . We compared trees that had been under previous attack with those under current attack and those that had no record of attack.

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Fungal species of the Ceratocystidaceae grow on their host plants using a variety of different lifestyles, from saprophytic to highly pathogenic. Although many genomes of fungi in the Ceratocystidaceae are publicly available, it is not known how the genes that encode catechol dioxygenases (CDOs), enzymes involved in the degradation of phenolic plant defense compounds, differ among members of the Ceratocystidaceae. The aim of this study was therefore to identify and characterize the genes encoding CDOs in the genomes of Ceratocystidaceae representatives.

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Article Synopsis
  • Macrotermitinae termites cultivate fungi as a food source, similar to human agriculture, by mixing plant material with fungal components in underground chambers.
  • The study identified specific volatile compounds emitted by the fungi, including α-pinene, camphene, and d-limonene, through genome analysis and gene expression, highlighting their significance in the termite-fungus symbiosis.
  • Research findings offer new insights into the metabolic capabilities of the fungus, revealing a rare enzyme that produces key volatile compounds and advancing our understanding of the interactions between these organisms in tropical ecosystems.
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Leaf blight caused by is one of the most important diseases of planted in the subtropics and tropics. In contrast, the better-known , though also a primary pathogen of , causes less damage to trees in these areas. Although is an aggressive pathogen, nothing is known about its infection biology.

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Fusarium circinatum is an important pathogen of pine trees. However, little is known regarding the molecular processes underlying its pathogenesis. We explored the potential role of the phytotoxin fusaric acid (FA) in the pathogenicity of the fungus.

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Climate change is expected to pose a global threat to forest health by intensifying extreme events like drought and insect attacks. Carbon allocation is a fundamental process that determines the adaptive responses of long-lived late-maturing organisms like trees to such stresses. However, our mechanistic understanding of how trees coordinate and set allocation priorities among different sinks (e.

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Water is vital for mammals. Yet, as ephemeral sources can be difficult to find, it raises the question, how do mammals locate water? Elephants (Loxodonta africana) are water-dependent herbivores that possess exceptional olfactory capabilities, and it has been suggested that they may locate water via smell. However, there is no evidence to support this claim.

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Conifer forests worldwide are becoming increasingly vulnerable to the effects of climate change. Although the production of phenolic compounds (PCs) has been shown to be modulated by biotic and abiotic stresses, the genetic basis underlying the variation in their constitutive production level remains poorly documented in conifers. We used QTL mapping and RNA-Seq to explore the complex polygenic network underlying the constitutive production of PCs in a white spruce () full-sib family for 2 years.

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Article Synopsis
  • * Researchers utilized genomic data from the Ceratocystidaceae family to analyze and identify the genes involved in the biosynthesis of ergosterol and other terpene-related compounds across nine fungal species.
  • * The study not only characterized the ergosterol content variation among different genera but also assessed the sensitivity of these fungi to a fungicide that inhibits ergosterol synthesis, revealing differing responses to various concentrations of the chemical.
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is a devastating plant pathogen that causes substantial losses in various agricultural crops. Although plants have developed some well-known defense mechanisms against invasive fungi, much remains to be learned about plant responses to fungal pathogens. In this study, we investigated how infection affects plant primary and secondary metabolism in the model plant .

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Ash dieback, a forest epidemic caused by the invasive fungus Hymenoscyphus fraxineus, threatens ash trees throughout Europe. Within Fraxinus excelsior populations, a small proportion of genotypes show a low susceptibility to the pathogen. We compared the metabolomes from a cohort of low-susceptibility ash genotypes with a cohort of high-susceptibility ash genotypes.

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Brassicales plants produce glucosinolates and myrosinases that generate toxic isothiocyanates conferring broad resistance against pathogens and herbivorous insects. Nevertheless, some cosmopolitan fungal pathogens, such as the necrotrophic white mold Sclerotinia sclerotiorum, are able to infect many plant hosts including glucosinolate producers. Here, we show that S.

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Plants are regularly colonised by fungi and bacteria, but plant-inhabiting microbes are rarely considered in studies on plant-herbivore interactions. Here we show that young gypsy moth (Lymantria dispar) caterpillars prefer to feed on black poplar (Populus nigra) foliage infected by the rust fungus Melampsora larici-populina instead of uninfected control foliage, and selectively consume fungal spores. This consumption, also observed in a related lepidopteran species, is stimulated by the sugar alcohol mannitol, found in much higher concentration in fungal tissue and infected leaves than uninfected plant foliage.

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Flavan-3-ols including the monomeric catechin and the polymeric proanthocyanidins (PAs) are abundant phenolic metabolites in poplar ( spp.) previously described to protect leaves against pathogen infection. However, it is not known whether stems are also defended in this way.

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