GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Morphometric and Molecular Diversity among Seven European Isolates of Pratylenchus penetrans
    MDPI AG ; 2021
    In:  Plants Vol. 10, No. 4 ( 2021-03-31), p. 674-
    Details
    In: Plants, MDPI AG, Vol. 10, No. 4 ( 2021-03-31), p. 674-
    Abstract: Pratylenchus penetrans is an economically important root-lesion nematode species that affects agronomic and ornamental plants. Understanding its diversity is of paramount importance to develop effective control and management strategies. This study aimed to characterize the morphological and genetic diversity among seven European isolates. An isolate from the USA was included in the molecular analyses for comparative purposes. Morphometrics of the European P. penetrans isolates generally were within the range of the original descriptions for this species. However, multiple morphometric characteristics, including body length, maximum body width, tail length and length of the post-vulval uterine sac showed discrepancies when compared to other populations. Nucleotide sequence-based analyses revealed a high level of intraspecific diversity among the isolates. We observed no correlation between D2-D3 rDNA- and COXI-based phylogenetic similarities and geographic origin. Our phylogenetic analyses including selected GenBank sequences also suggest that the controversy surrounding the distinction between P. penetrans and P. fallax remains.
    Type of Medium: Online Resource
    ISSN: 2223-7747
    URL: Article
    DOI: 10.3390/plants10040674
    Language: English
    Publisher: MDPI AG
    Publication Date: 2021
    detail.hit.zdb_id: 2704341-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    The Difference in the Bacterial Attachment among Pratylenchus neglectus Populations and Its Effect on the Nematode Infection
    MDPI AG ; 2022
    In:  Microorganisms Vol. 10, No. 8 ( 2022-07-27), p. 1524-
    Details
    In: Microorganisms, MDPI AG, Vol. 10, No. 8 ( 2022-07-27), p. 1524-
    Abstract: Different bacterial isolates attach to the cuticle of plant-parasitic nematodes, affecting their interactions with the host plant. Nematode populations differ in their genetic and cuticle structures, causing variable interactions with host plants and natural enemies. In the current study, attachment assays were carried out to compare the attachment of soil bacteria in general and the bacterial isolate of Rothia sp. in particular among geographically diverse populations of Pratylenchus neglectus. Biological and molecular assays were further conducted to examine the effect of Rothia attachment on nematode penetration into barley roots and to sequence the fatty acid- and retinol-binding gene (Pn-far-1). The results showed that nematode populations of P. neglectus differed in their bacterial attachment. Soil bacteria and Rothia sp. attached specifically to the cuticle of P. neglectus and did so differently among the nematode populations. Rothia attachment caused a reduction in the infectivity of three nematode populations in barley roots. The sequencing of the far-1 gene revealed genetic variability within and among P. neglectus populations. In conclusion, the interaction between P. neglectus and their bacterial attachers occurs in a population-specific manner, elucidating an essential aspect of using biological agents to manage plant-parasitic nematodes. Key Message: 1. Geographically diverse populations of the root lesion nematode Pratylenchus neglectus differed in the soil bacterial communities attached to their cuticles. 2. The bacterial isolate of Rothia sp. attached to the cuticle of P. neglectus and reduced its penetration into the host plant in a population-specific manner. 3. The fatty acid- and retinol-binding gene (far-1) varied within and among P. neglectus populations with their different bacterial attachment.
    Type of Medium: Online Resource
    ISSN: 2076-2607
    URL: Article
    DOI: 10.3390/microorganisms10081524
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2720891-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Report on the 42nd joint meeting of the DPG-working group Nematology and the working group “free living nematodes”
    Springer Science and Business Media LLC ; 2014
    In:  Journal of Plant Diseases and Protection Vol. 121, No. 4 ( 2014-8), p. 187-189
    Details
    In: Journal of Plant Diseases and Protection, Springer Science and Business Media LLC, Vol. 121, No. 4 ( 2014-8), p. 187-189
    Type of Medium: Online Resource
    ISSN: 1861-3829 , 1861-3837
    URL: Article
    DOI: 10.1007/BF03356509
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2014
    detail.hit.zdb_id: 2224048-2
    SSG: 12
    SSG: 21
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Genetic Variation among Heterodera schachtii Populations Coincided with Differences in Invasion and Propagation in Roots of a Set of Cruciferous Plants
    MDPI AG ; 2023
    In:  International Journal of Molecular Sciences Vol. 24, No. 7 ( 2023-04-06), p. 6848-
    Details
    In: International Journal of Molecular Sciences, MDPI AG, Vol. 24, No. 7 ( 2023-04-06), p. 6848-
    Abstract: Genes of host plants and parasitic nematodes govern the plant–nematode interaction. The biological receptors and parasitism effectors are variable among plant species and nematode populations, respectively. In the present study, hatch testing and bioassays on cabbage, oilseed radish, and mustard were conducted to compare the biological characteristics among six populations of the beet cyst nematode Heterodera schachtii. Genetic patterns of the vap1 gene for the studied populations were distinct as shown by denaturing the gradient gel electrophoresis of PCR-amplified gene fragments. Concurrently, significant differences in the hatching rates, number of penetrated J2 in roots, and eggs/cyst ratios among the six nematode populations for the three cruciferous species were observed. In conclusion, analyzing the population genetic structure of H. schachtii plays a pivotal role in illustrating the variability in the plant–nematode interaction among its populations and plant species, which in its role leads to developing nematode management depending on plant resistance.
    Type of Medium: Online Resource
    ISSN: 1422-0067
    URL: Article
    DOI: 10.3390/ijms24076848
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2019364-6
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Significant genetic differences among Heterodera schachtii populations within and among sugar beet production areas
    Brill ; 2020
    In:  Nematology Vol. 22, No. 2 ( 2020-02-10), p. 165-177
    Details
    In: Nematology, Brill, Vol. 22, No. 2 ( 2020-02-10), p. 165-177
    Abstract: Characterising the non-neutral genetic variation within and among populations of plant-parasitic nematodes is essential to determine factors shaping the population genetic structure. This study describes the genetic variation of the parasitism gene vap1 within and among geographic populations of the beet cyst nematode Heterodera schachtii . Forty populations of H. schachtii were sampled at four spatial scales: 695 km, 49 km, 3.1 km and 0.24 km. DGGE fingerprinting showed significant differences in vap1 patterns among populations. High similarity of vap1 patterns appeared between geographically close populations, and occasionally among distant populations. Analysis of spatially sampled populations within fields revealed an effect of tillage direction on the vap1 similarity for two of four studied fields. Overall, geographic distance and similarity of vap1 patterns of H. schachtii populations were negatively correlated. In conclusion, the population genetic structure was shaped by the interplay between the genetic adaptation and the passive transport of this nematode.
    Type of Medium: Online Resource
    ISSN: 1388-5545 , 1568-5411
    URL: Article
    DOI: 10.1163/15685411-00003297
    Language: Unknown
    Publisher: Brill
    Publication Date: 2020
    detail.hit.zdb_id: 2019332-4
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Effector gene vap1-based DGGE fingerprinting to assess variation within and among Globodera species and populations
    Brill ; 2019
    In:  Nematology Vol. 21, No. 10 ( 2019-11-12), p. 1023-1036
    Details
    In: Nematology, Brill, Vol. 21, No. 10 ( 2019-11-12), p. 1023-1036
    Abstract: Population-level genetic tools to study the epidemiology of potato cyst nematodes (PCN) are needed to evaluate their adaptive potential and validate management strategies. The effector gene vap1 is essential in early infection by PCN. We expected high allelic variation due to diversifying selection. A technique was developed specifically to amplify vap1 fragments of PCN, and electrophoretically separate variants in a denaturing gradient (DGGE). Sequenced gene variants differed in intron as well as exon regions. Siblings were more similar in vap1 pattern than juveniles from different cysts. Nearly all juveniles analysed had unique patterns with up to ten or five vap1 variants for Globodera pallida or G. rostochiensis , respectively. Patterns differed significantly among populations, with similarities increasing from between-species, within-species to within-pathotype comparisons. In conclusion, the method is suitable to determine the similarity of heterogeneous PCN populations for studies on their temporal change and spread.
    Type of Medium: Online Resource
    ISSN: 1388-5545 , 1568-5411
    URL: Article
    DOI: 10.1163/15685411-00003272
    Language: Unknown
    Publisher: Brill
    Publication Date: 2019
    detail.hit.zdb_id: 2019332-4
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Fungi isolated from cysts of the beet cyst nematode parasitized its eggs and counterbalanced root damages
    Springer Science and Business Media LLC ; 2021
    In:  Journal of Pest Science Vol. 94, No. 2 ( 2021-03), p. 563-572
    Details
    In: Journal of Pest Science, Springer Science and Business Media LLC, Vol. 94, No. 2 ( 2021-03), p. 563-572
    Abstract: Finding beneficial fungi antagonistic toward nematodes is important for developing more sustainable agricultural practices. We isolated abundant fungi from cysts of the beet cyst nematode Heterodera schachtii and tested their interaction with nematodes and sugar beet. By molecular screening of fungal communities colonizing five field populations of H. schachtii using DGGE and Sanger sequencing, three strains identified as Exophiala sp., Pochonia chlamydosporia and Pyrenochaeta sp. were frequently found in infected cysts and then specifically isolated (in pure culture). The three isolates were able to re-infect the cysts and colonize the eggs of H. schachtii in vitro fulfilling Koch’s postulates. In greenhouse trials, the root weight of sugar beet plants grown in substrates inoculated with nematodes and the fungal isolates was significantly higher compared to plants inoculated with nematodes only. The number of cysts propagated on roots was lower in substrates inoculated with Pyrenochaeta sp. than those in substrates inoculated with the other two fungi. However, cyst numbers did not significantly differ from the control because the propagation rate of the nematode increased with the root weight. The proportion of infected eggs per cyst was higher under the fungal treatments than the control, and it increased with the number of propagated cysts. The results showed that the here-studied strains of Exophiala sp., Pochonia chlamydosporia and Pyrenochaeta sp. were frequently found colonizing the nematode cysts of different populations of H. schachtii and were efficient in parasitizing the eggs of the nematode.
    Type of Medium: Online Resource
    ISSN: 1612-4758 , 1612-4766
    URL: Article
    DOI: 10.1007/s10340-020-01254-2
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2021
    detail.hit.zdb_id: 2141932-2
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Effector gene vap1 based DGGE fingerprinting to assess variation within and among Heterodera schachtii populations
    Walter de Gruyter GmbH ; 2018
    In:  Journal of Nematology Vol. 50, No. 4 ( 2018-01-01), p. 517-528
    Details
    In: Journal of Nematology, Walter de Gruyter GmbH, Vol. 50, No. 4 ( 2018-01-01), p. 517-528
    Abstract: Populations of beet cyst nematodes Heterodera schachtii vary in aggressiveness and virulence toward sugar beet varieties, but also in traits like host range, or decline rate in the field. Diversity of their essential pathogenicity gene vap1 is shaped by diversifying selection and gene flow. The authors developed a technique to study inter-population variation and intra-population diversity and dynamics of H. schachtii based on the gene vap1 . Degenerate primers were designed to amplify, clone, and sequence this gene from diverse species and populations of cyst nematodes. This resulted in a high diversity of sequences for H. schachtii , and allowed to design non-degenerated primers to amplify a fragment suitable for sequence dependent separation of gene variants in denaturing gradient gel electrophoresis (DGGE). The developed primers span a highly variable intron and part of a slightly variable exon. A marker comprised of the 14 mostly detected gene variants was established for gel-to-gel comparisons. For individual juveniles up to six gene variants were resolved and substantial variation within and among cysts was observed. A fast and easy DNA extraction procedure for 20 pooled cysts was established, which provided DGGE patterns with high similarity among replicate samples from field populations. Permutation tests on pairwise similarities within and among populations showed significant differences among vap1 patterns of field populations of H. schachtii . Similarly, gene diversity as expressed by the Shannon index was statistically different among field populations. In conclusion, the DGGE technique is a fast and – compared to sequencing approaches – inexpensive tool to compare populations of H. schachtii and link observed biological characteristics to genetic pattern.
    Type of Medium: Online Resource
    ISSN: 2640-396X
    URL: Article
    DOI: 10.21307/jofnem-2018-055
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2018
    detail.hit.zdb_id: 2443785-2
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Effects of Cover Cropping on Microbial Communities Associated with Heterodera schachtii and Nematode Virulence
    MDPI AG ; 2019
    In:  Soil Systems Vol. 3, No. 4 ( 2019-10-11), p. 67-
    Details
    In: Soil Systems, MDPI AG, Vol. 3, No. 4 ( 2019-10-11), p. 67-
    Abstract: Nematode-resistant cover crops can suppress populations of plant-parasitic nematodes. Samples of a loamy and a sandy loam soil were collected from two sugar beet fields in Lower Saxonia, northern Germany (“Jeinsen” and “Gross Munzel”) to measure the effects of cover cropping on the population genetic structure and infectivity of Heterodera schachtii as well as the composition of soil microbial communities. These fields allowed for a comparison of cover cropping with Brassica species resistant to Heterodera schachtii to fallow. In a series of radish bioassays with H. schachtii populations from Jeinsen and Gross Munzel, ratios of second-stage juveniles in roots per eggs in soil were higher in soil from under Brassica cropping than from under fallow. In denaturing gradient gelelectrophoresis, profiles of the parasitism gene vap1 differed between Brassica and fallow treatments in both populations. At Gross Munzel, microbes of soils and within nematode cysts differed between Brassica and fallow areas. Specifically, the frequency and occurrence of isolates of Pochonia chlamydosporia and Exophiala salmonis were lower within the cysts from Brassica than from fallow treatments. Overall, cover cropping with resistant Brassica species affected the bacteria and fungi infecting the cysts and subsequently, the infectivity of the H. schachtii population. Cover crop effects on nematode virulence (vap1 gene) and microbial colonization of the cysts could affect long-term nematode population dynamics.
    Type of Medium: Online Resource
    ISSN: 2571-8789
    URL: Article
    DOI: 10.3390/soilsystems3040067
    Language: English
    Publisher: MDPI AG
    Publication Date: 2019
    detail.hit.zdb_id: 2932897-4
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...