Attractivity or Repellence: Relation between the Endophytic Fungi of &i&Acalypha&/i&, &i&Colocasia&/i& and the Leaf-Cutting Ants—&i&Atta sexdens&/i&

摘要

Symbiotic relations are present in the nature and can contribute to the success of the organisms involved. Endophytic fungi live within the leaf tissues without causing any harm to the host plant, and some of them can be a defense mechanism against the attack by the leaf-cutting ants. Ants of the genus Atta are known as leaf-cutting ants and have an obligatory association with the fungus Leucoagaricus gongylophorus , cutting pieces of leaves and bringing them back to the colony to the fungus. The present study aimed to find out the endophytic fungi community of an attractive plant ( Acalypha wilkesiana ) and a less attractive plant ( Colocasia esculenta ) to the ants Atta sexdens . We found out that the communities are different in quantity and in composition and 73% of the isolated fungi were from A. wilkesiana , which has fungi known as attractive to leaf-cutting ants, such as genus Colletotrichum , Pestalotiopsis , Phomopsis and Xylaria . On the other hand, in C. esculenta , there was found the genus Fusarium , known to be reject by the leaf-cutting ants, and less fungal diversity than in the attractive plant A. wilkesiana . Therefore, our data suggest that attractivity or repelence of a plant to the leaf-cutting ants could be related to presence or ausence of determinated fungi more than the quantity of fungi present in a leaf.