Mutualism is the name given to interspecific interactions which result in benefit for all partners involved. However, such cooperation is open to opportunistic strategies: individuals that extract the benefit from the partner, but do not offer any benefit in exchange. The fig-fig wasp interaction is an appropriate case to study mutualistic interactions and opportunistic strategies (parasites of mutualism). Plants of the genus Ficus maintain a mutualistic interaction with tiny pollinating wasps (Agaonidae) and are exploited by other non-pollinating fig wasp species. This study aimed to assess the effect of non-pollinating wasps over the mutualistic relation between Ficus citrifolia (Moraceae) and its pollinator Pegoscapus tonduzi Grandi, 1919 (Hymenoptera, Agaonidae). We compared both seed (female plant function) and pollinating female (male plant function) production rates among samples of high- and low-infested figs by non-pollinating wasps, sampled in three Brazilian cities, Londrina (State of Paraná), Campinas and Ribeirão Preto (state of São Paulo), Brazil. Our results have shown a negative impact over both female and male floral reproductive components. This effect was higher on the male plant component (production of pollinating females). Pollinator production was approximately seven times lower in infested figs, whereas seed production was 1.5 times lower in those figs. We discuss hypotheses about mutualism stability with the occurrence of opportunistic species.
Competition; insect-plant interaction; Hymenoptera; Moraceae; pollination
