Abstract Detail

Recent Topics Posters

Headley, Alyssa [1], Finseth, Kaylee [1], Plenty, Nicole [1], Larsen, Garrett [1], Lazar, Frank [1], Siragusa, Gregory [1], Venkateshwaran, Muthu [2].

Unraveling the Complexity in the Signaling Pathways that Enable Symbiotic Association of Poplar with Diverse Group of Ectomycorrhizal Fungi.

More than 80 percent of land plants associate with arbuscular mycorrhizal (AM) fungi to meet their requirements for phosphorous, nitrogen and other micronutrients. These beneficial fungi are known as endomycorrhizae, because they colonize the host root tissues internally. Interestingly, woody perennials associate with another type of beneficial fungi, known as ectomycorrhizal (ECM) fungi, which establish external associations on the fine roots. Both types of mycorrhizal fungi act as extended root network, help plants acquire water and dissolved minerals. They also confer plants’ defense against soil-borne pathogens. Genetic studies in model plants have identified symbiotic signaling pathways that control AM colonization in plants. However, our knowledge on the symbiotic signaling pathways that control ectomycorrhization is rudimentary. Poplar (Populus sp.) associates with both endo- and ectomyocorrhizal fungi, enabling the characterization of signaling pathways that control both AM and ECM associations in a common system. Utilizing RNA interference (RNAi)-based gene knockdown strategy we have silenced the expression of three genes (CASTOR, POLLUX and DMI3) in poplar to characterize their role in both AM and ECM associations in this model plant. These three genes have been shown to play roles in AM symbiotic signaling in model legumes, such as Medicago truncatula and in ECM association in poplar with Laccaria bicolor.  We inoculated the control and transgenic lines with a commercial mycorrhizal fungal inoculum that contains 7 species of ECM fungi representing 3 genera and 9 species of AM fungi representing 4 genera. We found a reduction in the ECM colonization in the transgenic lines silenced for CASTOR and POLLUX. However, silencing DMI3 did not result in significant reduction in ECM colonization, suggesting the complexity in the signaling pathways that control poplar’s association with a diverse groups of ECM fungi.

1 - University of Wisconsin Platteville, 1 University Plaza, Platteville, WI, 53818, United States
2 - University of Wisconsin Platteville, School of Agriculture, 1 University Plaza, 212 Pioneer Tower, Platteville, WI, 53818, United States

plant-microbe interactions
symbiotic signaling.

Presentation Type: Recent Topics Poster
Number: PRT021
Abstract ID:1329
Candidate for Awards:None

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