A comparison of the community diversity of foliar fungal endophytes between seedling and adult loblolly pines (Pinus taeda)

Abstract

Fungal endophytes represent one of the most ubiquitous plant symbionts on Earth and are phylogenetically diverse. The structure and diversity of endophyte communities have been shown to depend on host taxa and climate, but there have been relatively few studies exploring endophyte communities throughout host maturity. We compared foliar fungal endophyte communities between seedlings and adult trees of loblolly pines (Pinus taeda) at the same seasons and locations by culturing and culture-independent methods. We sequenced the internal transcribed spacer region and adjacent partial large subunit nuclear ribosomal RNA gene (ITS–LSU amplicon) to delimit operational taxonomic units and phylogenetically characterize the communities. Despite the lower infection frequency in seedlings compared to adult trees, seedling needles were receptive to a more diverse community of fungal endophytes. Culture-free method confirmed the presence of commonly cultured OTUs from adult needles but revealed several new OTUs from seedling needles that were not found with culturing methods. The two most commonly cultured OTUs in adults were rarely cultured from seedlings, suggesting that host age is correlated with a selective enrichment for specific endophytes. This shift in endophyte species dominance may be indicative of a functional change between these fungi and their loblolly pine hosts.

Double‐digest RADseq loci using standard Illumina indexes improve deep and shallow phylogenetic resolution of Lophodermium, a widespread fungal endophyte of pine needles

“…Green needles were washed and surface‐sterilized as described in Oono et al. (2015). Green needles were cut with a sterile razor blade into 2‐mm‐long sections.…”

What do we learn from cultures in the omics age? High-throughput sequencing and cultivation of leaf-inhabiting endophytes from beech (Fagus sylvatica L.) revealed complementary community composition but similar correlations with local habitat conditions

“…Similar conclusions were made by Langarica-Fuentes et al (2014) who identified a biased composition of compost fungi by cultivation. Recently, HTS was rated superior over cultivation, given its ability to detect more obligate, slow growing and rare fungi (Al-Sadi et al 2015, Oono et al 2015. Whereas the general lack of congruence between mycobiomes generated by cultivation and HTS can be safely postulated nowadays (Pitkaranta et al 2008), much less is known about environmental correlations of these differing data sets.…”

Fungal endophytic communities associated to the phyllosphere of grapevine cultivars under different types of management

“…Fungal endophytes are ubiquitous, they have been found within all plants from the diverse habitats examined to date (Kumaresan & Suryanarayanan 2001;Schulz et al 2002;Rodriguez et al 2009;Pancher et al 2012). The endophytic community in a single plant is usually composed by numerous and systematically diverse species of fungi (Petrini 1991;Oono et al 2015). Their number and species composition is influenced by factors such as the environment (Saona et al 2010;Yousaf et al 2010;N unez-Trujillo et al 2012), plant physiology (Islam et al 2010), anthropogenic factors (Rasche et al 2006), and pathogen infections (Araujo et al 2002;Bulgari et al 2011;Buyer et al 2011).…”

“…Endophytes have been gaining attention in the past decade in areas such as medicine, agriculture, and industry, mostly due to the vast potential uses of their chemically diverse secondary metabolites (Tao et al 2008;Rodriguez et al 2009) and their roles within plants (Oono et al 2015). Several studies have shown that some fungal endophytes have beneficial effects on their hosts.…”

“…Several studies have shown that some fungal endophytes have beneficial effects on their hosts. They may act as plant growth promoters; confer tolerance to environmental stresses and pathogen and herbivore attacks, the latter for instance by decreasing the palatability of the host tissue to herbivores through the production of toxic compounds (Arnold et al 2003;Miller et al 2008;Bae et al 2009;Oono et al 2015). The role of endophytes in pathogen defence is attained through different mechanisms, namely the induction of systemic resistance, through the accumulation of pathogenesis-related (PR) proteins, expression of plant defence genes; the production of secondary metabolites that inhibit fungal growth and the competition with pathogens for the same ecological niches in terms of nutrients and space (Arnold et al 2003;Gonzalez & Tello 2011).…”