Fungi-macroalgae associations in Potter Cove

MARTORELL, MARIA M.; LANNERT MICAELA; MATULA CAROLINA; QUARTINO LILIANA; RUBERTO LAM; MAC CORMACK, WALTER

Hobart

Conferencia; SCAR OPEN SCIENCE CONFERENCE 2020; 2020

SCAR (Scientific Committee on Antarctic Research)

Aiming to study fungi-macroalgae associations in Potter Cove (25 de Mayo/King George Island, Southern Shetlands) 18 different species of macroalgae were sampled and screened for fungal growth. Fungal isolates (48) were recovered only from six macroalgae species (Gigartina skottsbergii, Palmaria decipiens, Neuroglossum delesseriae, Adenocystis utricularis, Ballia callitricha, Ascoseira mirabilis). These isolates were characterized considering their morphology and growth performance (colony diameter) on potato dextrose agar (PDA) at different temperatures (5 to 35°C). Only 12.5% of the isolates were able to grow at 35°C and, surprisingly, 18.75% were not able to grow at 5°C. All the isolates were able to grow at 15 and 25°C, while 75 % presented the largest colony diameter after 25 days at 25°C. Nevertheless, some isolates grew faster during the first incubation period at a temperature different from that where they showed the largestdiameter at 25 days. This could be related to different metabolic adaptation to temperature that each isolate can put forth. After redundancy checking, 38 isolates were identified by molecular biology. Most of them belonged to Penicillium and Cladosporium genera, while others showed to be Cadophora, Antarctomyces, Mycochaetophora, and Pseudogymnoascus. No fungal growth was obtained from the other 12 macroalgae sampled, suggesting a possible antagonistic relation between some of them and the marine fungi in Potter Cove.