Who are the nitrogen fixing endophytes of Dryas octopetala in the European Arctic?

Dryas octopetala (mountain avens, lapinvuokko) is an arctic-alpine plant species in family Rosaceae. It is a small evergreen shrub with long life-span (up to >100 y). In the Younger and Oldes Dryas stadials (geological periods of cold global climate) the species had a wide distribution throughout the northern hemisphere. Currently it is widespread in the entire Arctic and in the mountaneous regions of northern hemisphere. D. octopetala is abundant in habitats with very low soil nitrogen content, including sandy and gravel soils, and in recently deglaciated areas. In Alaska and Canada, several Dryas species have been found in symbiosis with nitrogen fixing actinobacterial species Frankia, where the bacteria provides plant with nitrogen, enabling colonization of barren, nutrient poor soils. However, no actinorhizal nodules have been found in D. octopetala in Europe, and the current hypothesis is, that climatic or other barriers have prevented the migration or establishment of the endophytic Frankia to Europe. Despite this, D. octopetala is dominant in glacier foreland communities in European arctic and alpine regions.

The goal of this MSc project is to identify the diatzotrophic bacteria associated with D. octopetala in the high and low arctic as well as alpine habitats in the Europe, and study the impact of climate, geography and plant tissue type to diatzotroph community. The project will use molecular approaches (DNA isolation, PCR, sequencing, as well as protein isolation), and will involve work in the laboratory as well as in the field (Kilpisjärvi area). The proposed starting date for the project is in the spring-summer 2015

For more information, contact: Riitta Nissinen ( [email protected] , room C215.2) or Manoj Kumar ([email protected])