Una nueva especie de Hexamermis Steiner, 1924 (Nematoda, Mermithidae) parásito de Epilachna paenulata (Germar, 1824) (Coleopera, Coccinellidae) en Argentina

Se describe a Hexamermis bonaerensis sp. n. un parásito de Epilachna paenulata (Germar, 1824) (Coleoptera, Coccinellidae) en Argentina. Se caracteriza por tener los anfídios de tamaño mediano y de forma oval redondeada. La vagina es musculosa y ligeramente protuberante, con una rama descendente que forma un asa antes de unirse al útero. Presenta tres hileras de papilas genitales: la ventrolateral en una hilera con trece papilas; la hilera ventral con dos papilas preanales simples, tres pares y dos preanales únicas, y con cinco pares de papilas postanales. Publicación registrada en Zoobank:LSIDurn:lsid:zoobank.org:pub:9F5EA90D-381D-4FC8-8F0F-86B9E1D2F014 Acto nomenclatural:LSIDurn:lsid:zoobank.org:act:35252E81-2E50-4F12-94DF-FC3617971627

Differential anti-insect activity of natural products isolated from Dodonaea viscosa Jacq. (Sapindaceae)

Botanical biopesticides constitute an important tool for Integrated Pest Management practices. Uruguay has a great potential for developing botanical biopesticides from its abundant native flora. Dodonaea viscosa Jacq. is a native Sapindaceae that in preliminary studies was shown to possess a potential deterrent activity against insect models. In this work, ethanolic extracts of the leaves of this species were studied. Bioguided fractionation and supercritical fluid extraction led to the isolation of active compounds. For that purpose four insect models were used: Epilachna paenulata, Spodoptera littoralis, Myzus persicae, and Rhopalosiphum padi, which are pests of crops of economic importance. Lupeol, stigmasterol, stigmast-7-en-3-ol, and a labdane diterpene were isolated and showed differential activity against the models.

Induced-feeding bioassays for detection of Bacillus thuringiensis insecticidal activity against Epilachna paenulata (Coleoptera)

The objective of this work was to establish and test the induced-feeding bioassay in order to detect Bacillus thuringiensis insecticidal activity against Epilachna paenulata (Coleoptera: Coccinellidae). Larvae were induced to swallow high concentrations of spore-crystal suspensions of seven exotic and 30 Argentine B. thuringiensis strains. The great majority of strains showed no toxicity to E. paenulata larvae, and observed mortality was lower than 30%. Induced-feeding bioassay is feasible, and should be used for prospecting strains that produce right combinations of Cry proteins needed to an efficient pest control.