Insects associated with cultivation of orchid Dendrobium phalaenopsis Fitzg. in the state of Bahia, Brazil

This study investigated the occurrence of insects associated to the cultivation of orchid Dendrobium phalaenopsis Fitzg. in nurseries in Bahia State. The analyses were performed through Dominance indices (D), Shannon-Weiner diversity (H’), Margalef and Pielou’s Equitability (J’), while the Pearson correlation analysis was used to verify the correlation between the occurrence magnitude of insects with environmental variables (temperature, humidity, precipitation, and wind speed). Univariate statistics were used through a cross contingency table, differentiating classes from categories using the Chi-square test and the multiple correspondence analysis. We collected 927 adult individuals and the Coccinellidae (Coleoptera) family was the most abundant. We obtained 39 genera, distributed in 49 morphospecies, and most taxa identified were collected on the leaves of orchids. The most abundant taxa were Diomus spp. (Coleoptera: Coccinellidae), Leptophysa sp.1 (Coleoptera: Chrysomelidae), Thaliabaris sp. (Coleoptera: Curculionidae), Dynaspidiotus sp., Furcaspis sp.1 (Hemiptera: Diaspididae), Tenthecoris sp. (Hemiptera: Miridae), and Pheidole sp. (Hymenoptera: Formicidae). The large commercial nursery showed the highest species diversity with Shannon-Wiener index (H’=3.008), Margalef (6.454), and dominance (D=0.071). Species uniformity was higher in the small commercial nursery (J’=0.9579). This study contributes to the valuation of entomofauna of orchid and it is the first list of insects associated to orchid cultivation in Bahia State, Brazil. It also presents the first record of mealybug Dynaspidiotus sp. and beetles Leptophysa sp. and Thaliabaris sp. in orchid cultivation in Bahia State.