Abstract Detail

Mycology

Chen, Ko-Hsuan [1], Vilgalys, Rytas [2], Hoeksema, Jason [3], Plett, Jonathan [4], Anderson, Ian [4], Powell, Jeff [4], Louie, Katherine [5], Bowen, Benjamin [5], Northen, Trent [5], Liao, Hui-ling [6].

Plant phenotypes and metabolomes imply changes of plant-fungal interactions across an anthropogenic California-Australia pine invasion gradient.

Anthropogenic activities often alter species distribution across the globe. Pinus radiata which is native to the northern hemisphere has been widely planted in the southern hemisphere for over 200 years. Additionally, P. radiata invades the native land of many southern hemisphere countries, including the native Eucalyptus forest in Australia. Soil microbes, especially ectomycorrhizal fungi, are believed to play critical roles in facilitating P. radiata invasion through their symbiotic partnership. The plant-soil-microbial interactions may affect the distribution of microorganisms and result in microbial-mediated changes in plant fitness and biogeochemistry. To infer the soil-plant-microbial interactions across P. radiata invasion gradient, we investigated plant phenotypes and metabolomics of reciprocal plant host and soil bioassay experiments. We planted P. radiata (native to California) and E. globus (native to Australia) in soil collected from three different forest types (native P. radiata forest in California, P. radiata plantation in Australia, and native Eucalyptus forest in Australia) across the pine invasion gradient. Plant biomass and mycorrhization rate were measured. Our results showed that both P. radiata and E. globus had greater biomass in soil collected from native Eucalyptus forest in comparison with soil from pine plantation and native pine forest. E. globus had the highest mycorrhization rate in the soil of native Eucalyptus forest compared to soil of pine plantation and native pine forest, indicating high compatibility between E. globus and the native ectomycorrhizal fungal community. Surprisingly, P. radiata demonstrated a similar mycorrhizal rate regardless of the soil origin, suggesting ectomycorrhizal fungi compatible with P. radiata are available in Australia. Using LC-MS analysis, 70 selected metabolites relevant to plant-microbial interactions were measured from roots/root washed-off. Trehalose, a carbohydrate storage form of ectomycorrhizal fungi, was positively correlated with the mycorrhization rate of both plant hosts. Several antioxidants likely involve in plant defense, including caffeic acid and hydroxybenzoic acid, showed a negative correlation with the mycorrhizal rate of both plant hosts. When planted in soil from the Eucalyptus native forests, the root wash-off of P. radiata and E. globus showed divergent patterns for several organic acids likely involved in nutrient solubility in soil. For example, quinic acid was higher in P. radiata while glutamic acid was higher in E. globus root wash-off. Our results uncovered an unexpected plant-fungal relationship across the pine invasion gradient. Plant phenotypes, including mycorrhization rate, are influenced by soil origin. The metabolome is highly relevant to the mycorrhization rate, plant host identity, and soil origin.

1 - Academia Sinica, Biodiversity Research Center
2 - Duke University, Biology
3 - University of Mississippi, Department of Biology
4 - Western Sydney University, Hawkesbury Institute for the Environment
5 - Department of Energy, Joint Genome Institute
6 - University of Florida, North Florida Research and Education Center

Keywords:
Ectomycorrhizal fungi
metabolomics
invasion
Pinus
Eucalyptus
Mycology.

Presentation Type: Oral Paper
Session: MY7, Mycology: Fungus-Plant Interactions: Arbuscular Mycorrhizae, Climate Change, and Microbiome
Location: /
Date: Friday, July 23rd, 2021
Time: 10:00 AM(EDT)
Number: MY7001
Abstract ID:590
Candidate for Awards:None