Glomeromycota
Arbuscular Mycorrhizal Fungi
Taxonomic Classification
Overview
Glomeromycota comprises fungi that form arbuscular mycorrhizae (AM), one of the most widespread and ancient symbiotic relationships on Earth. These fungi colonize the roots of approximately 80% of plant species, forming highly branched structures (arbuscules) within plant cells. This mutualistic relationship, dating back over 400 million years, was likely crucial for plant colonization of land and remains vital for ecosystem functioning today.
Key Characteristics
- Form arbuscular mycorrhizal associations with plant roots
- Coenocytic hyphae without regular septa
- Obligate symbionts, cannot complete lifecycle without host plants
- Produce large multinucleate spores (40-800 μm)
- No known sexual reproduction
- Ancient lineage dating to early land plant evolution
Ecological Role
Fundamental to terrestrial ecosystem functioning, facilitating nutrient uptake (especially phosphorus) for the vast majority of land plants. Improve plant drought resistance, disease resistance, and soil structure. Form extensive hyphal networks connecting multiple plants, facilitating resource sharing and communication.
Diversity
Approximately 300-350 described species, though molecular studies suggest much higher cryptic diversity
Reproduction
Reproduce asexually through large spores and hyphal fragmentation. No sexual stage has been documented. Genetic exchange may occur through anastomosis (hyphal fusion).
Distribution
Worldwide in virtually all terrestrial ecosystems except extreme environments
Notable Features
- Form symbiosis with ~80% of land plant species
- Crucial for plant nutrition, especially phosphorus uptake
- Among oldest known symbioses (400+ million years)
- Cannot be cultured without host plants
- Single species may contain hundreds of genetically distinct nuclei
- Essential for sustainable agriculture and ecosystem restoration
Economic Importance
- Critical for sustainable agriculture and reduced fertilizer use
- Ecosystem restoration and revegetation
- Improving crop yield and plant health
- Carbon sequestration in soils
- Biofertilizer production
- Phytoremediation enhancement
Example Species
Explore representative species from Glomeromycota that demonstrate the diversity and importance of this phylum.
AMF
Rhizophagus irregularis (formerly Glomus intraradices)
Rhizophagus irregularis is perhaps the most commercially important and widely studied arbuscular mycorrhizal fungus. For...
AM Fungus
Funneliformis mosseae
Funneliformis mosseae is a widespread arbuscular mycorrhizal fungus commercially important in agriculture. Like other AM...
Giant-spored AM Fungus
Gigaspora margarita
Gigaspora margarita is an arbuscular mycorrhizal fungus notable for producing exceptionally large spores (up to 800 micr...