Seed and Root Endophytic Fungi in a Range Expanding and a Related Plant Species

Abstract

Climate change is accelerating the spread of plants and their associated species to new ranges. The differences in range shift capacity of the various types of species may disrupt long-term co-evolved relationships especially those belowground, however, this may be less so for seed-borne endophytic microbes. We collected seeds and soil of the range-expanding Centaurea stoebe and the congeneric Centaurea jacea from three populations growing in Slovenia (native range of both Centaurea species) and the Netherlands (expanded range of C. stoebe, native range of C. jacea). We isolated and identified endophytic fungi directly from seeds, as well as from roots of the plants grown in Slovenian, Dutch or sterilized soil to compare fungal endophyte composition. Furthermore, we investigated whether C. stoebe hosts a reduced community composition of endophytes in the expanded range due to release from plant-species specific fungi while endophyte communities in C. jacea in both ranges are similar. We cultivated 46 unique and phylogenetically diverse endophytes. A majority of the seed endophytes resembled potential pathogens, while most root endophytes were not likely to be pathogenic. Only one endophyte was found in both roots and seeds, but was isolated from different plant species. Unexpectedly, seed endophyte diversity of southern C. stoebe populations was lower than of populations from the north, while the seed endophyte community composition of northern C. stoebe populations was significantly different southern C. stoebe as well as northern and southern C. jacea populations. Root endophyte diversity was considerably lower in C. stoebe than in C. jacea independent of plant and soil origin, but this difference disappeared when plants were grown in sterile soils. We conclude that the community composition of fungal endophytes not only differs between related plant species but also between populations of plants that expand their range compared to their native habitat. Our results suggest that fungal endophytes of two Centaurea species are not able to systemically infect plants. We highlight that endophytes remain poorly studied and further work should investigate the functional importance of endophytes.

Latitudinal variation in soil nematode communities under climate warming‐related range‐expanding and native plants

“…These results suggest different responses of nematodes to range-expanding C. stoebe in the new compared to the original range, as has also been demonstrated for its seed-and root-associated fungal communities (Geisen et al, 2017). One of the four range-expanding plant species, C. stoebe, showed a stronger shift in genus-level nematode community composition between the original range in Central Europe and the new range in North-Western Europe than the congeneric native C. jacea.…”

Endophytes of industrial hemp (Cannabis sativaL.) cultivars: identification of culturable bacteria and fungi in leaves, petioles, and seeds

“…and Cladosporium sp.) were recovered from seeds, and both are reported elsewhere as seed endophytes (Hodgson et al 2014;Geisen et al 2017).…”

Tissue-Specific and Geographical Variation in Endophytic Fungi of Ageratina adenophora and Fungal Associations With the Environment

“…Endophytic fungi commonly have been categorized into two groups based on their manner of transmission: vertically transmitted endophytes (VTEs, e.g., Neotyphodium) that inhabit temperate grasses (Lolium) and are transmitted from the mother plant (Müller and Krauss, 2005) and horizontally transmitted endophytes (HTEs) transmitted mostly via spores from plant to plant (Arnold, 2007). Previous studies on native plants and crops indicated that fungal endophyte communities varied based on host genotypes (Emi and Kenji, 2013), plant tissues (Wearn et al, 2012), growth stages (Shi et al, 2016), and distribution areas (Geisen et al, 2017). However, most reports to date have addressed VTEs when exploring the endophytes of invasive plants (Rudgers et al, 2005); only very few studies have focused on the interaction between HTEs and invasive plants (Newcombe et al, 2009;Aschehoug et al, 2012).…”