@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{dutta_houdinet_nandakafle_kafle_hawkes_garcia_2023, title={Agrobacterium tumefaciens-mediated transformation of Nigrospora sp. isolated from switchgrass leaves and antagonistic toward plant pathogens}, volume={215}, ISSN={["1872-8359"]}, url={http://dx.doi.org/10.1016/j.mimet.2023.106849}, DOI={10.1016/j.mimet.2023.106849}, abstractNote={Nigrospora is a diverse genus of fungi colonizing plants through endophytic, pathogenic, or saprobic interactions. Endophytic isolates can improve growth and development of host plants, as well as their resistance to microbial pathogens, but exactly how they do so remains poorly understood. Developing a reliable transformation method is crucial to investigate these mechanisms, in particular to identify pivotal genes for specific functions that correlate with specific traits. In this study, we identified eight isolates of Nigrospora sp. internally colonizing the leaves of switchgrass plants cultivated in North Carolina. Using an Agrobacterium tumefaciens-mediated transformation approach with control and GFP-expressing vectors, we report the first successful transformation of two Nigrospora isolates. Finally, we demonstrate that wild-type and transgenic isolates both negatively impact the growth of two plant pathogens in co-culture conditions, Bipolaris maydis and Parastagonospora nodorum, responsible for the Southern Leaf Blight and Septoria Nodorum Blotch diseases, respectively. The GFP-transformed strains developed here can therefore serve as accurate reporters of spatial interactions in future studies of Nigrospora and pathogens in the plant. Finally, the transformation method we describe lays the foundation for further genetic research on the Nigrospora genus to expand our mechanistic understanding of plant-endophyte interactions.}, journal={JOURNAL OF MICROBIOLOGICAL METHODS}, author={Dutta, Summi and Houdinet, Gabriella and NandaKafle, Gitanjali and Kafle, Arjun and Hawkes, Christine V. and Garcia, Kevin}, year={2023}, month={Dec} }