Guarana plant is a native of the Amazon region. Due to its high amount of caffeine and tannins, the seed has medicinal and stimulating properties. The guarana industry has grown exponentially in recent years; however, little information is available about associated mycobiota, particularly endophytic fungi. The present study aimed to compare the distribution and diversity of endophytic fungi associated with the leaves and seeds of anthracnose-resistant and susceptible guarana plants produced in Maués and Manaus, Amazonas State, Brazil. A total of 7514 endophytic fungi were isolated on Potato Dextrose Agar, Sabouraud and Czapek media, and grouped into 77 morphological groups. Overall, fungal communities in guarana leaves and seeds were mainly composed by Colletotrichum and Fusarium genera, but also by Chondrostereum, Clonostachys, Curvularia, Hypomontagnella, Lentinus, Neopestalotiopsis, Nigrospora, Peroneutypa, Phyllosticta, Simplicillium and Tinctoporellus. Obtained results indicate that some members of Colletotrichum and Fusarium genera may have experienced dysbiosis during the guarana domestication process, suggesting that some individuals may behave as latent pathogens. The susceptible guarana genotype cultivated in Manaus presented higher fungal diversity. The relative abundance of taxa and diversity among samples suggests that communities are structured by genotype and geographic location. This is the first report of mycobiota in both guarana leaves and seeds.

In January 2018, eucalyptus trees showing wilt symptoms were identified in a commercial plantation located in the Quevedo Cantón, Los Ríos province, Ecuador. Disease incidence reached 40% of the eu...

The study of microorganisms associated with tropical plant species, particularly fungi, has garnered significant interest due to their potential applications in biological control and the synthesis of pharmacologically active compounds. This research aimed to identify and characterize the endophytic fungal communities associated with cocoa (Theobroma cacao L.) fruits across three municipalities in the Orellana province, located within the Ecuadorian Amazon. Fungi were isolated directly from cocoa fruits and analyzed through comprehensive cultural, morphological, and molecular analyses. The diversity of fungal taxa was evaluated using metrics of relative abundance and species richness. A total of 464 fungal isolates were obtained, representing 56 distinct morphotypes and 14 genera within the phylum Ascomycota. The most abundant genera included Penicillium sp. (27.8%), Epicoccum sp. (20.5%), Lasiodiplodia sp. (10.1%), Trichoderma sp. (9.91%), and Fusarium sp. (9.70%). Notably, in the municipality of La Joya de los Sachas, a higher number of endophytic fungi was observed, encompassing 14 genera. This study provides critical insights into the diversity and distribution of fungal communities associated with cocoa fruits in the northern Ecuadorian Amazon. These findings have important implications for the management of cocoa diseases and the discovery of novel bioactive compounds. Future investigations should explore the functional roles of these fungi, particularly their potential as biocontrol agents or sources of novel pharmaceuticals. Furthermore, examining the effects of environmental variables and agricultural practices on cocoa fruit mycobiota may contribute to a deeper understanding of the ecological dynamics within this system.