Biology subjects

van der Heijden, M. G.

Publications and source records attributed to van der Heijden, M. G..

2 recordsLinked to original sources

bioRxiv2024

Bluetongue virus serotype 12 in the Netherlands in 2024 - A BTV serotype reported in Europe for the first time

Bluetongue (BT) is a viral midge borne disease primarily affecting ruminants such as sheep, cattle, and goats. In 2023, the Netherlands reported the first case of bluetongue virus serotype 3 (BTV-3), after being BTV free for eleven years. Since May 2024, vaccination with inactivated BT vaccines for serotype 3 was applied in the Netherlands. Nonetheless, in late June/July 2024, BTV-3 re-emerged and spread over large parts of Europe. In October 2024, BTV-12 was identified by follow-up diagnostics after a BTV-3 vaccinated sheep with signs of BT was tested positive for BTV but negative for serotype 3. This marks a significant event, as BTV-12 had never been reported in Europe. Screening of farms in close proximity to the sheep farm and retrospective analysis of previously BTV PCR positive tested clinical suspicions, resulted in nine BTV-12 affected farms in total. The emergence of BTV-12 in the Netherlands raises important questions about the route of introduction of BT in the Netherlands and mechanisms of viral spread of this specific serotype. Possible adaptation of new BTV serotypes to the European climatic and husbandry conditions prompts reconsideration of surveillance, prevention, and control strategies in relation to changing ecological conditions and vector dynamics. The initial findings, respective studies as well as the initial attempts to trace the origin of BTV-12 are described.

zoology↗

bioRxiv2018

Agricultural intensification reduces microbial network complexity and the abundance of keystone taxa in roots

Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different farming systems on the root microbiota and it is still unclear whether agricultural intensification influences network complexity of microbial communities. We investigated the impact of conventional, no-till and organic farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic farming harboured a much more complex fungal network than conventional and no-till farming systems. The abundance of keystone taxa was the highest under organic farming where agricultural intensification was the lowest. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiota.

microbiology↗