A new report of a fungal association in Targonia L. (Marchantiophyta)

COTTET, A.C.; MESSUTI, M.I.

S.C. de Bariloche

Simposio; II International Symposium: Mycorrhizal Symbiosis in South America; 2019

INIBIOMA-IPATEC-CONICET

Several land non-vascular plants, such as bryophytes, are known to form associations with different groups of fungi. Within these, the arbuscular fungi include representatives of Glomeromycotina (arbuscular mycorrhizal, AM) and Mucoromycotina (fine endophyte, FE). Both groups have been registered living in association with liverworts (Marchantiophyta). As an example of this fungal colonization, we can mention the association established between the AM fungi and the complex liverworts of Targionia L. (T. hypophyla L.). The aim of this work was to know if the other species of this genus also distributed in Argentina, T. stellaris (Müll. Frib.) Hässel, form fungal associations. Collected specimens come from to northwest Argentina (Tafí del Valle, Tucumán) growing on rocky slope at c. 3000 masl. They were collected, herborized and identified using traditional techniques for the study of bryophytes. The colonization by the fungi was observed staining the gametophyte under the recently proposed technique for these plants. The thallus is dark green, dyed purple on both sides, gregariously adhered to the substrate by unicellular rhizoids. In cross-section, the dorsal surface is smooth, concave in the middle and progressively flat towards the margins with simple epidermal pores with a single ring of 6-7 thin-walled cells; air chambers in a single layer with green filaments and basal tissue that extends to three quarters of the height of the thallus. The colonization of the FE was evidenced by the presence of characteristic fungal structures. The aseptate hyphae were observed, mainly in the middle ventral portion of the thallus, the external hyphae close to the rhizoids, and the internal measure c. 3-4 μm in diameter; intracellular arbuscules with hyphae ranged from 1 to 3 μm in diameter; vesicles were not observed. The presence of FE was restricted to the non-photosynthetic part of the plant, where the colonization percentage reaches 8% (5%-10%). In this contribution, we present the FE association with T. stellaris, which also constitutes the first mention of this for the genus.