Multi scale assessment on soil microbiota quality and dispersion in wheat fields : organic vs. conventional farming


06/12/19 - Séminaires de Claire RICONO, Lorène MARCHAND et Emma JEAVONS

Le vendredi 6 décembre 2019 à 13h00, salle UFR SVE, bâtiment 13, Campus de Beaulieu, UR1

Multi scale assessment on soil microbiota quality and dispersion in wheat fields : organic vs. conventional farming

Symbiotic microorganisms are key functional group due to their action favoring plant nutrition and protection. Loss of biodiversity can reduce these functions and promote parasitic behavior evolution leading to lower plant’s performance. This work will address the impact of tree hedges in agricultural landscapes, supposing that they constitute a microorganisms biodiversity refuge, and will analyze the consequences of agricultural practices on soil and wheat roots microbial community.

Contact : Claire RICONO

Morphological variability in relation to environmental conditions in the endemic cushion plant Lyallia kerguelensis from Kerguelen Islands

The sub-Antarctic Kerguelen Islands are exposed to extreme environmental conditions (low temperatures, strong winds and frequent frost events). However, rapid climate change is occurring. Lyallia kerguelensis Hook.f. (Montiaceae), an endemic cushion plant from Kerguelen, is particularly infrequent in the archipelago, specialized in certain habitats and thus might be endangered. In addition, many cushions show necrosis. Our objectives were to characterize the morphology of the cushions and to determine the potential effect of environmental variables on it.

Contact : Lorène MARCHAND

When complementary resources fail to increase top down control: an answer in trophic food webs?

Biological control of herbivores by natural enemies is expected to be enhanced through increased plant diversity. Nevertheless, field studies provide contrasting results of habitat management strategies on herbivore control. Here, we tested the effect of intercropped floral resources on cereal aphid control by parasitoids and on an aphid-parasitoidhyperparasitoid trophic food web. While the addition of floral resources did not increase aphid control, it affected the parasitoid guild and favoured hyperparasitoids, thus providing a deeper understanding of bottom up and top down effects in plant-herbivore-natural enemy interaction webs.

Contact : Emma JEAVONS