Sucking herbivore assemblage composition on greenhouse Ficus correlates with host plant leaf architecture

Abstract

Understanding arthropod herbivore selectivity trends towards host plant attributes is essential for predicting plant-associated herbivore assemblage structure. Little is known about such interactions between spontaneous herbivore species and cultivated plants under specific conditions of botanical garden greenhouses. In this study, the taxonomic and functional composition of sucking arthropod herbivore assemblages were correlated with leaf anatomical and surface features of 33 host species of Ficus L. (Moraceae) across four distantly located greenhouse complexes of botanical gardens. The analyses revealed that the species number and abundance of scale insects and their individual families, sessile phloem feeders, total phloem feeders and total herbivores were significantly positively correlated with the thickness of leaf lamina, epidermis and mesophyll, stomatal length and width, and the presence of abaxial multiple epidermis and weak ferruginous non-glandular trichomes. Significant negative correlations were revealed between the same herbivore parameters and the density of glandular trichomes. Heliomorphic leaves supported higher abundance and species richness of sessile phloem feeders compared to sciomorphic ones. The parameters of some phloem and mesophyll feeder taxa also correlated with non-glandular trichome length and density, type of trichomes and epicuticular wax layer, and the presence of calcium oxalate crystals in the epidermis. Results of the study suggest that the leaf architecture-related herbivory trends under greenhouse conditions are similar to those occurring in natural ecosystems when considering the functional significance of particular leaf traits, and remain relevant at the scale of particular plant taxa with disregard of spatial factor.