Microfungi Associated to the Yeast agriculture Ant, Cyphomyrmex minutus

In the fungus-growing ant interaction, the attine ants cultivate a fungus (Basidiomycota: Leucoprinus) and protect their cultivar from specific pathogen (Ascomycota: Hypocreales) using the antibiotic production capacity of Actinobacteria (Pseudonocardia). Three different genera of fungus-growing ants are known from Puerto Rico. Of these, Cyphomyrmex minutus is the only species that cultivates its fungus in yeast form. Although the interaction in the attine ant symbiosis has been extensively studied, the yeast-cultivating ants and their microbial associates in the Caribbean have not been described. We want to identify the cultivar, investigate the presence of pathogen Escovopsis and the microfungi community associated to Cyphomyrmex minutus cultivar. Samples were taken from twenty six different nests in the Cambalache Tropical Forest, Puerto Rico during the Dry and Rainy Seasons. The cultivar was identified using culture independent DNA isolation, amplification and sequencing of the 28S rDNA. Microfungi associates and the cultivar were classified and characterized using morphology and culture dependent molecular methods.  We amplify the ribosomal DNA using and sequence with Internal Transcribe Spacer (ITS) primers. From the two sampling seasons we isolated 156 microfungi in association with C. minutus cultivar and we identified 36 different genera. The most frequent fungi were:  Trichoderma spirale , Furarium spp. ,  Aspergillus spp. and Penicillium spp. These results represent an important contribution to understanding of the complex interaction between yeast-growing ants and the microbial community that includes the microfungi associates to the cultivar in the nest.