Most studies examining endophytic fungi associated with grasses (Poaceae) have focused on agronomically important species in managed ecosys- tems or on wild grasses in subtropical, temperate and boreal grasslands. However grasses first arose in tropical forests, where they remain a significant and diverse component of understory and forest-edge communities. To provide a broader context for understanding grass-endophyte associations we char- acterized fungal endophyte communities inhabiting foliage of 11 species of phylogenetically diverse C3 grasses in the understory of a lowland tropical forest at Barro Colorado Island, Panama. Our sample included members of early-arising subfamilies of Poaceae that are endemic to forests, as well as more recently arising subfamilies that transitioned to open environments. Isolation on culture media and direct PCR and cloning revealed that these grasses harbor species-rich and phylogenetically diverse communities that lack the endophytic Clavicipitaceae known from diverse woodland and pasture grasses in the temper- ate zone. Both the incidence and diversity of endophytes was consistent among grass species regardless of subfamily, clade affiliation or ancestral habitat use. Genotype and phylogenetic analyses suggest that these endophytic fungi are predominant- ly host generalists, shared not only among distinctive lineages of Poaceae but also with non-grass plants at the same site.

Culturing and direct PCR suggest prevalent host generalism among diverse fungal endophytes of tropical forest grasses

Even highly mutually beneficial microbial-plant interactions, such as mycorrhizal- and rhizobial-plant exchanges, involve selfishness, cheating and power-struggles between the partners, which depending on prevailing selective pressures, lead to a continuum of interactions from antagonistic to mutualistic. Using manipulated grass-endophyte combinations in a five year common garden experiment, we show that grass genotypes and genetic mismatches constrain genetic combinations between the vertically (via host seeds) transmitted endophytes and the out-crossing host, thereby reducing infections in established grass populations. Infections were lost in both grass tillers and seedlings in F1 and F2 generations, respectively. Experimental plants were collected as seeds from two different environments, i.e., meadows and nearby riverbanks. Endophyte-related benefits to the host included an increased number of inflorescences, but only in meadow plants and not until the last growing season of the experiment. Our results illustrate the importance of genetic host specificity and trans-generational maternal effects on the genetic structure of a host population, which act as destabilizing forces in endophyte-grass symbioses. We propose that (1) genetic mismatches may act as a buffering mechanism against highly competitive endophyte-grass genotype combinations threatening the biodiversity of grassland communities and (2) these mismatches should be acknowledged, particularly in breeding programmes aimed at harnessing systemic and heritable endophytes to improve the agriculturally valuable characteristics of cultivars.

/pdf/genetic-compatibility-determines-endophyte-grass-1k740crkkg.pdf

Genetic Compatibility Determines Endophyte-Grass Combinations

The interaction of endophyte–grass associations are conditional on nitrogen (N) availability, but the reported responses of these associations to N are inconsistent. We hypothesized that this inconsistency is caused, at least in part, by phosphorus (P) availability. In this experiment, we compared the performance of endophyte-infected (EI) and endophyte-free (EF) Achnatherum sibiricum subjected to four treatments comprising a factorial combination of two levels of N (N+ vs. N−, i.e. N supply vs. N deficiency) and two levels of P (P+ vs. P−, i.e. P supply vs. P deficiency) availability. The results showed that A. sibiricum–Neotyphodium associations were conditional on both N and P availability, but more conditional on N than P. Under N+P− conditions, endophyte infection significantly improved acid phosphatase activity of EI plants, such that the biomass of EI plants was not affected by P deficiency (i.e. similar growth to N+P+ conditions), and resulted in more biomass in EI than EF plants. Under N−P+ conditions, biomass of both EI and EF decreased compared with N+P+; however, EI biomass decreased slowly by decreasing leaf N concentration more rapidly but allocating higher fractions of N to photosynthetic machinery compared with EF plants. This change of N allocation not only improved photosynthetic ability of EI plants but also significantly increased their biomass. Under N−P− conditions, EI plants allocated higher fractions of N to photosynthesis and had greater P concentrations in roots, but there was no significant difference in biomass between EI and EF plants. Our results support the hypothesis that endophyte–grass interactions are dependent on both N and P availability. However, we did not find a clear cost of endophyte infection in A. sibiricum.

/pdf/endophyte-mediated-effects-on-the-growth-and-physiology-of-4fheyp3p9g.pdf

Endophyte-Mediated Effects on the Growth and Physiology of Achnatherum sibiricum Are Conditional on Both N and P Availability

Endophytes of native grasses from South America: Biodiversity and ecology

Effects of simultaneous infections of endophytic fungi and arbuscular mycorrhizal fungi on the growth of their shared host grass Achnatherum sibiricum under varying N and P supply

A survey of grass species associated with Neotyphodium and Epichloe fungal endophytes was made in the permanent grasslands of northern China. A total of 41 grass species, 56 sites and 172 local populations were examined to reveal endophytic infection of native grasses. Twenty-five of the forty-one species of grasses (proportionately 0·61) were infected by endophytes: twenty-two species had a mean infection rate of 0·01–0·50 and only three species had a mean infection >0·50. Of the 172 local populations examined, however, proportionately 0·72 were not infected, 0·181 had an infection rate of 0·01–0·50 and 0·099 had an infection rate of 0·51–1·00. Two genera of grasses, Cleistogenes and Koeleria, as well as twenty plant species, were previously unknown endophytic hosts in China. High infection rates (0·86–1·00) of plants of Achnatherum sibiricum were detected at all eleven sites studied. Other grasses in which high infection rates were found were Agropyron mongolicum, Roegneria turczaninovii, Agropyron elongate, Poa palustris and Poaangustifolia. It was concluded that endophytes are found widely in natural grass populations and that endophyte–grass interactions may have effects on ecosystems and livestock in the grasslands of northern China.

Occurrence of endophytes in grasses native to northern China

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Y. K. Wei

Author Tools

Chat about Author

Papers

Occurrence of endophytes in grasses native to northern China