Condicionalidade nas interações ecológicas: características morfológicas e variações fenológicas afetando o sistema Malpighiaceae-formiga-herbívoros

Ants commonly participate simultaneously in mutualisms with honeydew-producing hemipterans and extrafloral nectar bearing host plants, protecting plants against herbivores and hemipterans against their natural enemies. However, the benefit may vary according to the species of ant interacting and the outcomes for the plant productivity will depend on the results of plant-ant-hemipteran relationship. We studied a plant-mealybug association with Camponotus crassus Mayr (Formicinae) and Ectatomma tuberculatum Olivier (Ectatomminae) in a Brazilian Tropical Savanna. Our main hypothesis was that mealybugs compete for ant’s attendance indirectly affecting the host plant productivity. Results showed that only C. crassus affected positively the survivorship of mealybugs and, consequently, decreased the host plant productivity. Thus, we provided further evidence that ant-plant mutualism can be highly conditional in relation to ant species, reinforcing the hypothesis that ants can differ greatly in their deterrent abilities and the importance of their physiological and morphological traits conditioning the outcomes of these relationships.