33 research outputs found

    Integrated Proteomic and Metabolomic Profiling of Phytophthora cinnamomi Attack on Sweet Chestnut (Castanea sativa) Reveals Distinct Molecular Reprogramming Proximal to the Infection Site and Away from It

    Get PDF
    Phytophthora cinnamomi is one of the most invasive tree pathogens that devastates wild and cultivated forests. Due to its wide host range, knowledge of the infection process at the molecular level is lacking for most of its tree hosts. To expand the repertoire of studied Phytophthora-woody plant interactions and identify molecular mechanisms that can facilitate discovery of novel ways to control its spread and damaging effects, we focused on the interaction between P. cinnamomi and sweet chestnut (Castanea sativa), an economically important tree for the wood processing industry. By using a combination of proteomics, metabolomics, and targeted hormonal analysis, we mapped the effects of P. cinnamomi attack on stem tissues immediately bordering the infection site and away from it. P. cinnamomi led to a massive reprogramming of the chestnut proteome and accumulation of the stress-related hormones salicylic acid (SA) and jasmonic acid (JA), indicating that stem inoculation can be used as an easily accessible model system to identify novel molecular players in P. cinnamomi pathogenicity.O

    A survey in natural forest ecosystems of Vietnam reveals high diversity of both new and described Phytophthora taxa including P. ramorum

    Get PDF
    In 2016 and 2017, surveys of Phytophthora diversity were performed in 25 natural and semi-natural forest stands and 16 rivers in temperate and subtropical montane and tropical lowland regions of Vietnam. Using baiting assays from soil samples and rivers and direct isolations from naturally fallen leaves, 13 described species, five informally designated taxa and 21 previously unknown taxa of Phytophthora were isolated from 58 of the 91 soil samples (63.7%) taken from the rhizosphere of 52 of the 64 woody plant species sampled (81.3%) in 20 forest stands (83.7%), and from all rivers: P. capensis, P. citricola VII, VIII, IX, X and XI, P. sp. botryosa-like 2, P. sp. meadii-like 1 and 2, P. sp. tropicalis-like 2 and P. sp. multivesiculata-like 1 from Phytophthora major phylogenetic Clade 2; P. castaneae and P. heveae from Clade 5; P. chlamydospora, P. gregata, P. sp. bitahaiensis-like and P. sp. sylvatica-like 1, 2 and 3 from Clade 6; P. cinnamomi (Pc), P. parvispora, P. attenuata, P. sp. attenuata-like 1, 2 and 3 and P. ×heterohybrida from Clade 7; P. drechsleri, P. pseudocryptogea, P. ramorum (Pr) and P. sp. kelmania from Clade 8, P. macrochlamydospora, P. sp. ×insolita-like, P. sp. ×kunnunara-like, P. sp. ×virginiana-like s.l. and three new taxa, P. sp. quininea-like, P. sp. ×Grenada 3-like and P. sp. ×Peru 4-like, from Clade 9; and P. sp. gallica-like 1 and 2 from Clade 10. The A1 and A2 mating types of both Pc and Pr co-occurred. The A2 mating type of Pc was associated with severe dieback of montane forests in northern Vietnam. Most other Phytophthora species, including Pr, were not associated with obvious disease symptoms. It is concluded that (1) Vietnam is within the center of origin of most Phytophthora taxa found including Pc and Pr, and (2) Phytophthora clades 2, 5, 6, 7, 8, 9, and 10 are native to Indochina.info:eu-repo/semantics/publishedVersio

    Ligninolytické enzymy rodu Trametes

    No full text
    Eighty-four strains belonging to four species of the genus Trametes Fr. (T. versicolor, T. hirsuta, T. ochracea and T. cervina) collected in different localities and on different substrates were screened for laccase production and eight of them with their monokaryotic derivates were then examined in more detail for their ability to produce also other lignin-modifying enzymes (manganese peroxidase and lignin peroxidase). Production variability was relatively high and no significant correlation was found between the origin of the strains (locality, substrate) and the enzyme production. Dikaryons of all three species (but not of all their strains) exhibited LiP activity, which was not detected in the respective monokaryons

    Mixed-Mating Model of Reproduction Revealed in European <i>Phytophthora cactorum</i> by ddRADseq and Effector Gene Sequence Data

    No full text
    A population study of Phytophthora cactorum was performed using ddRADseq sequence variation analysis completed by the analysis of effector genes—RXLR6, RXLR7 and SCR113. The population structure was described by F-statistics, heterozygosity, nucleotide diversity, number of private alleles, number of polymorphic sites, kinship coefficient and structure analysis. The population of P. cactorum in Europe seems to be structured into host-associated groups. The isolates from woody hosts are structured into four groups described previously, while isolates from strawberry form another group. The groups are diverse in effector gene composition and the frequency of outbreeding. When populations from strawberry were analysed, both asexual reproduction and occasional outbreeding confirmed by gene flow among distinct populations were detected. Therefore, distinct P. cactorum populations differ in the level of heterozygosity. The data support the theory of the mixed-mating model for P. cactorum, comprising frequent asexual behaviour and inbreeding alternating with occasional outbreeding. Because P. cactorum is not indigenous to Europe, such variability is probably caused by multiple introductions of different lineages from the area of its original distribution, and the different histories of sexual recombination and host adaptation of particular populations

    Morphological and phylogenetic studies of two new neotropical species of Loweomyces (Polyporales, Basidiomycota)

    No full text
    The genus Loweomyces is characterized by resupinate to pileate, sessile to stipitate basidiomes, monomitic to dimitic hyphal system with presence of pseudoskeletal hyphae, thin-walled hymenial cystidia, and usually cyanophilous spore and hyphal walls. The genus has not been widely accepted and some authors placed Loweomyces species in Abortiporus, Tyromyces or Antrodiella. During a survey of polypores in southern Brazil, two unidentified species with similar features to Loweomyces spp. were found. Morphological and molecular studies were carried out in order to understand their morphological and evolutionary relationships and to confirm their phylogenetic placement and taxonomic identity. DNA sequences of the internal transcribed spacer and large subunit of ribosomal RNA gene were used for phylogenetic studies. Both studied species have similar morphological characteristics to other Loweomyces spp. and group close to L. fractipes phylogenetically; therefore, Loweomyces spissus and L. tomentosus are proposed as new species. Full descriptions, illustrations of microscopic features, and an identification key to the accepted species in the genus are presented.Fil: Westphalen, Mauro C.. Instituto de Botanica de Sao Paulo; BrasilFil: Tomšovský, Michal. Mendelova Univerzita V Brne; República ChecaFil: Rajchenberg, Mario. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gugliotta, Adriana M.. Instituto de Botanica de Sao Paulo; Brasi

    The effect of military boots on front kick dynamics

    No full text
    Front kicks are often used in combat activities that involve the use of kicks and punches, including close combat military training. To mimic real-life combative environments where soldiers execute forceful front kicks while wearing military boots, it is logical to wear these boots during close combat training. However, the effect of military footwear on front kick forces remain unknown. Therefore, the aim of this study was to compare the effects of military boots on front kick dynamics. Six male soldiers (23.3 ± 1.7 yr, 74.3 ± 6.2 kg, 175.5 ± 4.5 cm) performed eight individual front kicks with no military boots, in bare feet (NB) and with military boots (MB). Peak force (N), impulse (N.s) and time to reach peak force (ms), were measured during each kick. Data were analyzed using paired sample t-tests or nonparametric Wilcoxon pair test and Cohen’s d. Results. Neither peak force (3180 ± 647 N) nor impulse (367 ± 40 N.s) of MB were different than NB (3157 ± 291 N and 360 ± 48 N.s, respectively) (p = 0.85; d = 0.04 and p = 0.36; d = 0.12, respectively). Peak force was reached in a significantly shorter time during MB (39 ± 16 ms) compared to NB (56 ± 8 ms; d = −0.88). Conclusion. Peak force was reached in a shorter time using MB compared to barefoot (NB) front kicks. The use of military boots changes the time course of peak force during the front kick

    Growth Rates of Lymantria dispar Larvae and Quercus robur Seedlings at Elevated CO2 Concentration and Phytophthora plurivora Infection

    No full text
    Interactions between plants, insects and pathogens are complex and not sufficiently understood in the context of climate change. In this study, the impact of a root pathogen on a leaf-eating insect hosted by a tree species at elevated CO2 concentration is reported for the first time. The combined and isolated effects of CO2 and infection by the root pathogen Phytophthora plurivora on English oak (Quercus robur) seedlings were used to assess growth rates of plants and of gypsy moth (Lymantria dispar) larvae. For this purpose, two Q. robur provenances (Belgrade and Sombor) were used. At ambient CO2 concentration, the relative growth rates of larvae consuming leaves of plants infected by P. plurivora was higher than those consuming non-infected plants. However, at elevated CO2 concentration (1000 ppm) higher relative growth rates were detected in the larvae consuming the leaves of non-infected plants. At ambient CO2 concentration, lower growth rates were recorded in L. dispar larvae hosted in Q. robur from Belgrade in comparison to larvae hosted in Q. robur from Sombor. However, at elevated CO2 concentration, similar growth rates irrespective of the provenance were observed. Defoliation by the gypsy moth did not influence the growth of plants while P. plurivora infection significantly reduced tree height in seedlings from Belgrade. The results confirm that a rise of CO2 concentration in the atmosphere modifies the existing interactions between P. plurivora, Q. robur, and L. dispar. Moreover, the influence of the tree provenances on both herbivore and plant performance at elevated CO2 concentrations suggests a potential for increasing forest resilience through breeding

    Integrated Proteomic and Metabolomic Profiling of Phytophthora cinnamomi Attack on Sweet Chestnut (Castanea sativa) Reveals Distinct Molecular Reprogramming Proximal to the Infection Site and Away from It

    No full text
    Phytophthora cinnamomi is one of the most invasive tree pathogens that devastates wild and cultivated forests. Due to its wide host range, knowledge of the infection process at the molecular level is lacking for most of its tree hosts. To expand the repertoire of studied Phytophthora&ndash;woody plant interactions and identify molecular mechanisms that can facilitate discovery of novel ways to control its spread and damaging effects, we focused on the interaction between P. cinnamomi and sweet chestnut (Castanea sativa), an economically important tree for the wood processing industry. By using a combination of proteomics, metabolomics, and targeted hormonal analysis, we mapped the effects of P. cinnamomi attack on stem tissues immediately bordering the infection site and away from it. P. cinnamomi led to a massive reprogramming of the chestnut proteome and accumulation of the stress-related hormones salicylic acid (SA) and jasmonic acid (JA), indicating that stem inoculation can be used as an easily accessible model system to identify novel molecular players in P. cinnamomi pathogenicity
    corecore