Integrating quantitative morphological and qualitative molecular methods to analyze soil nematode community responses to plant range expansion

1. Belowground nematodes are important for soil functioning, as they are ubiquitous and operate at various trophic levels in the soil food web. However, morphological nematode community analysis is time consuming and requires ample training. qPCR-based nematode identification techniques are well available, but high throughput sequencing (HTS) might be more suitable for non-targeted nematode community analysis. 2. We compared effectiveness of qPCR and HTS-based approaches with morphological nematode identification while examining how climate warming-induced plant range expansion may influence belowground nematode assemblages. We extracted nematodes from soil of Centaurea stoebe and C. jacea populations in Slovenia, where both plant species are native, and Germany, where C. stoebe is range expander and C. jacea is native. Half of each nematode sample was identified morphologically and the other half was analysed using targeted qPCR and a novel HTS approach. 3. HTS produced the highest tax...