Artigo Acesso aberto Produção Nacional Revisado por pares

Relationships between host plant architecture and gall abundance and survival

2008; Entomological Society of Brazil; Volume: 52; Issue: 1 Linguagem: Inglês

10.1590/s0085-56262008000100014

ISSN

1806-9665

Autores

Daniela P. Lara, Lázaro A. Oliveira, Islaine Franciely Pinheiro de Azevedo, Márcia F. Xavier, Fernando A. O. Silveira, Marco Antônio Alves Carneiro, G. Wilson Fernandes,

Tópico(s)

Hymenoptera taxonomy and phylogeny

Resumo

The plant architecture hypothesis predicts that variation in host plant architecture influences insect herbivore community structure, dynamics and performance. In this study we evaluated the effects of Macairea radula (Melastomataceae) architecture on the abundance of galls induced by a moth (Lepidoptera: Gelechiidae). Plant architecture and gall abundance were directly recorded on 58 arbitrarily chosen M. radula host plants in the rainy season of 2006 in an area of Cerrado vegetation, southeastern Brazil. Plant height, dry biomass, number of branches, number of shoots and leaf abundance were used as predicting variables of gall abundance and larval survival. Gall abundance correlated positively with host plant biomass and branch number. Otherwise, no correlation (p > 0.05) was found between gall abundance with shoot number or with the number of leaves/plant. From a total of 124 galls analyzed, 67.7% survived, 14.5% were attacked by parasitoids, while 17.7% died due to unknown causes. Larvae that survived or were parasitized were not influenced by architectural complexity of the host plant. Our results partially corroborate the plant architecture hypothesis, but since parasitism was not related to plant architecture it is argued that bottom-up effects may be more important than top-down effects in controlling the population dynamics of the galling lepidopteran. Because galling insects often decrease plant fitness, the potential of galling insects in selecting for less architectural complex plants is discussed.

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