Behaviour 2019
Make do with what you have: predatory wasp as the first line of defense in weevil-infested plant
Helena Maura Torezan-Silingardi1, Isamara Mendes2, Drielly Queiroga2, Eduardo Calixto2, Kleber Del-Claro1. 1UFU - Universidade Federal de Uberlandia, Uberlandia, MG, Brazil; 2USP- Univ. de São Paulo, Ribeirão Preto, SP, Brazil

We investigated the impacts of ants and the wasp Bachygastra lecheguana on the reproductive success of two weevil-infested sympatric Banisteriopsis (Malpighiaceae) species, addressing the behavioral mechanisms by which wasps find endophytic herbivores. By experimentally manipulating the presence of ants, wasps and herbivores on plants, as well as the potential cues used by the wasp to find the weevils, we observed that (i) ants fail to protect plants against floral endophytic beetles; (ii) predation of weevil larvae by wasps increased the number of flowers developed from buds, but not fruit set in B. malifolia; (iii) wasp predatory activity does not increase the number of flowers nor fruits in B. laevioflia; and (iv) wasps use a combination of visual, chemical and tactile cues to find endophytic weevil larva. For the first time, we identified potential eco-physiological mechanisms utilized by B. lecheguana to find endophytic beetle larvae. Overall, our study shows direct and indirect effects of the predators on the reproductive success of Banisteriopsis species, and the conditionalities of this system.