Design and evaluation of nematode 18S rDNA primers for PCR and denaturing gradient gel electrophoresis (DGGE) of soil community DNA (original) (raw)
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We used complementary morphological and DNA metabarcoding approaches to characterize soil nematode communities in three cropping systems, conventional till (CT), no-till (NT) and organic (ORG), from a long-term field experiment. We hypothesized that organic inputs to the ORG system would promote a more abundant nematode community, and that the NT system would show a more structured trophic system (higher Bongers MI) than CT due to decreased soil disturbance. The abundance of Tylenchidae and Cephalobidae both showed positive correlations to soil organic carbon and nitrogen, which were highest in the ORG system. The density of omnivore-predator and bacterial-feeding nematodes was reduced in NT soils compared to CT, while some plant-parasitic taxa increased. NT soils had similar Bongers MI values to CT, suggesting they contained nematode communities associated with soils experiencing comparable levels of disturbance. Metabarcoding revealed within-family differences in nematode diversit...
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Cereal cyst nematodes (Heterodera spp.) are a significant threat to global cereal production systems and choosing the correct management strategy requires knowledge and identification of various species. We conducted a survey across the main cereal-growing regions of the Republic of Azerbaijan in 2017. Cyst-forming nematodes were detected in 34 samples (44.7%), of which 28 were identified as H. filipjevi or H. avenae using internal transcribed spacer (ITS)-rDNA sequencing. Six populations were unidentifiable to species level and were recorded as belonging to the H. avenae group. H. filipjevi was the dominant species, found in 19 samples (25%) from the provinces of Qobustan, Ismailli, Oguz, Sheki, Barda, and Kurdamir. H. avenae was detected in 9 samples (11.8%) across the provinces of Ismailli, Oguz, and Sheki. ITS-rDNA phylogenetic analyses showed that populations of H. filipjevi clustered in one group with two subgroups, all supported by high bootstrap values. Populations of H. ave...
Nematode 28 S rDNA sequences for selected taxa in Figure 3 . Species Isolate Locality Accession
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