@article{rose_dellinger_larmour_polishook_higuita-aguirre_dutta_cook_zimmermann_garcia_2024, title={The ectomycorrhizal fungus <i>Paxillus ammoniavirescens</i> influences the effects of salinity on loblolly pine in response to potassium availability}, volume={26}, ISSN={["1462-2920"]}, url={https://doi.org/10.1111/1462-2920.16597}, DOI={10.1111/1462-2920.16597}, abstractNote={AbstractSalinity is an increasing problem in coastal areas affected by saltwater intrusion, with deleterious effects on tree health and forest growth. Ectomycorrhizal (ECM) fungi may improve the salinity tolerance of host trees, but the impact of external potassium (K+) availability on these effects is still unclear. Here, we performed several experiments with the ECM fungus Paxillus ammoniavirescens and loblolly pine (Pinus taeda L.) in axenic and symbiotic conditions at limited or sufficient K+ and increasing sodium (Na+) concentrations. Growth rate, biomass, nutrient content, and K+ transporter expression levels were recorded for the fungus, and the colonization rate, root development parameters, biomass, and shoot nutrient accumulation were determined for mycorrhizal and non‐mycorrhizal plants. P. ammoniavirescens was tolerant to high salinity, although growth and nutrient concentrations varied with K+ availability and increasing Na+ exposure. While loblolly pine root growth and development decreased with increasing salinity, ECM colonization was unaffected by pine response to salinity. The mycorrhizal influence on loblolly pine salinity response was strongly dependent on external K+ availability. This study reveals that P. ammoniavirescens can reduce Na+ accumulation of salt‐exposed loblolly pine, but this effect depends on external K+ availability.}, number={3}, journal={ENVIRONMENTAL MICROBIOLOGY}, author={Rose, Benjamin D. and Dellinger, Marissa A. and Larmour, Clancy P. and Polishook, Mira I. and Higuita-Aguirre, Maria I. and Dutta, Summi and Cook, Rachel L. and Zimmermann, Sabine D. and Garcia, Kevin}, year={2024}, month={Mar} }
 @article{richardson_rose_garcia_2024, title={X-ray fluorescence and XANES spectroscopy revealed diverse potassium chemistries and colocalization with phosphorus in the ectomycorrhizal fungus Paxillus ammoniavirescens}, volume={128}, ISSN={["1878-6162"]}, url={https://doi.org/10.1016/j.funbio.2024.08.004}, DOI={10.1016/j.funbio.2024.08.004}, abstractNote={Ectomycorrhizal (ECM) fungi play a major role in forest ecosystems and managed tree plantations. Particularly, they facilitate mineral weathering and nutrient transfer towards colonized roots. Among nutrients provided by these fungi, potassium (K) has been understudied compared to phosphorus (P) or nitrogen (N). The ECM fungus Paxillus ammoniavirescens is a generalist species that interacts with the root of many trees and can directly transfer K to them, including loblolly pine. However, the forms of K that ECM fungi can store is still unknown. Here, we used synchrotron potassium X-ray fluorescence (XRF) and K-edge X-ray Absorption Near Edge Structure (XANES) spectroscopy on P. ammoniavirescens growing in axenic conditions to investigate the K chemistries accumulating in the center and the edge of the mycelium. We observed that various K forms accumulated in different part of the mycelium, including K-nitrate (KNO}, number={6}, journal={FUNGAL BIOLOGY}, author={Richardson, Jocelyn A. and Rose, Benjamin D. and Garcia, Kevin}, year={2024}, month={Oct}, pages={2054–2061} }
 @article{rose_frank_garcia_2023, title={Development of split-root assays for loblolly pine (Pinus taeda L.) seedlings to study ectomycorrhizal symbioses}, volume={10}, ISSN={2215-0161}, url={https://doi.org/10.1016/j.mex.2023.102046}, DOI={10.1016/j.mex.2023.102046}, abstractNote={Split-root techniques are valuable to investigate systemic vs. local plant responses to biotic and abiotic environmental factors, including interactions with soil microbes. Loblolly pine (Pinus taeda L.) is an economically important tree species that associates with many ectomycorrhizal fungi. However, a protocol for the establishment of split-roots experiments with loblolly pine has not been described so far. This method successfully establishes a split-root system in eight weeks following germination of loblolly pine seedlings. Rapid lateral root elongation is promoted by cutting the primary root tip and growing the seedlings in a hydroponic medium. Lateral roots can then be divided into two separated compartments and inoculated with ectomycorrhizal fungi. The method was validated by growth of split roots with or without inoculation. Root dry biomass was not significantly different between separated non-inoculated roots. Ectomycorrhizal colonization was not detected on the non-inoculated side of roots that were inoculated only on one side, demonstrating the success of the technique as a valuable method for split-root experiments in P. taeda. In addition to ectomycorrhizal fungi, researchers can use this method with loblolly pine to study systemic and local responses to a variety of other biotic or abiotic factors in the root environment.•We describe a protocol to produce split-roots in loblolly pine (Pinus taeda L.) in eight weeks.•This protocol uses hydroponics to promote the elongation of loblolly pine roots.•We validated this protocol by determining split-root biomass and inoculating the seedlings with the ectomycorrhizal fungi Paxillus ammoniavirescens or Hebeloma cylindrosporum.}, journal={METHODSX}, author={Rose, Benjamin D. and Frank, Hannah E. R. and Garcia, Kevin}, year={2023} }
 @article{hackman_rose_frank_vilgalys_cook_garcia_2022, title={NPK fertilizer use in loblolly pine plantations: Who are we really feeding?}, volume={520}, ISSN={["1872-7042"]}, url={https://doi.org/10.1016/j.foreco.2022.120393}, DOI={10.1016/j.foreco.2022.120393}, abstractNote={Optimizing loblolly pine (Pinus taeda L.) productivity using fertilizers and various site management practices has been a goal of foresters for decades. Nitrogen (N), phosphorus (P), and potassium (K) are the three most operationally applied fertilizers to loblolly pine silviculture and are of primary importance to their total productivity. Fertilizer recommendations for N, P, and K in loblolly pine are primarily made on abiotic factors such as site and soil characteristics, while the biological factors controlling nutrient uptake are typically overlooked in the production and optimization of these stands. Arguably the most important of these biological factors are the diverse ectomycorrhizal fungal (ECM) communities that colonize the fine roots of almost all loblolly pine trees. The mantle formed by ECM fungi on short-root tips presents a barrier for direct apoplastic uptake of N, P, and K from soil solution by pine roots. In well-colonized roots, the tree is dependent on symplastic fungal transport of N, P, and K foraged from the soil by the extraradical hyphal network. This raises the question: Who are we really feeding if the ECM fungi are the ones assimilating most of the tree's total nutritional requirements? Considering multiple species of ECM fungi can inhabit a single root system, many questions remain regarding the drivers of colonization, why some species are more efficient at taking up and exchanging nutrients with their hosts than others, and why certain fertilizers directly affect the morphology of ECM growth. The purposes of this review are (1) to explore how the most commonly commercially applied macronutrients, N, P, and K, affect the relationship between loblolly pine and ECM communities, and (2) to propose future directions to investigate, preserve, and manipulate these interactions in pine plantations to optimize productivity.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Hackman, Jacob J. and Rose, Benjamin D. and Frank, Hannah E. R. and Vilgalys, Rytas and Cook, Rachel L. and Garcia, Kevin}, year={2022}, month={Sep} }
 @misc{houdinet_guerrero-galan_rose_garcia_zimmermann_2023, title={Secrets of the fungus-specific potassium channel TOK family}, volume={31}, ISSN={["1878-4380"]}, DOI={10.1016/j.tim.2022.11.007}, abstractNote={Several families of potassium (K+) channels are found in membranes of all eukaryotes, underlining the importance of K+ uptake and redistribution within and between cells and organs. Among them, TOK (tandem-pore outward-rectifying K+) channels consist of eight transmembrane domains and two pore domains per subunit organized in dimers. These channels were originally studied in yeast, but recent identifications and characterizations in filamentous fungi shed new light on this fungus-specific K+ channel family. Although their actual function in vivo is often puzzling, recent works indicate a role in cellular K+ homeostasis and even suggest a role in plant–fungus symbioses. This review aims at synthesizing the current knowledge on fungal TOK channels and discussing their potential role in yeasts and filamentous fungi.}, number={5}, journal={TRENDS IN MICROBIOLOGY}, publisher={Elsevier BV}, author={Houdinet, Gabriella and Guerrero-Galan, Carmen and Rose, Benjamin D. and Garcia, Kevin and Zimmermann, Sabine D.}, year={2023}, month={May}, pages={511–520} }