No abstract

1 Extensive variation to damage by the invasive gall-forming wasp Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae) is known to exist amongst Eucalyptus genotypes. 2 In the present study, 30 of the 50 tested genotypes were susceptible to gall formation and development of the wasp. Gall development on the petiole and leaves of plants was compared to calculate the percentage of infestation per plant and per genotype. 3 A positive correlation between galls on petioles and leaves indicated an absence of specificity at this level, and also that either leaves or petioles could be used to obtain an accurate estimate of the level of infestation. 4 Genotypes of E. nitens × E. grandis and E. grandis × E. camaldulensis were most susceptible, with a maximum damage index value for leaves and petioles of 0.52 and 0.39, respectively. Eucalyptus dunii, E. nitens, E. smithii, E. urophylla and E. saligna × E. urophylla showed little or no infestation. 5The results obtained in the present study suggest that the selection and planting of resistant/less susceptible genotypes will be an important aid in managing damage from L. invasa invasion.

No abstract

DNA extraction from minute hymenopterans and their larvae is difficult and challenging because of their small size indicating a low amount of starting material. Hence, 11 DNA extraction methods were compared to determine their efficacy in isolating DNA. Success of each method was scored on a 2% agarose gel after PCR of the cox 1 mitochondrial locus. A silica-membrane-based approach was the most successful, followed by a method using a combination of incubation buffers and a method using magnetic beads. The method using buffers was the most cost- and time effective. Using this method, larvae from Eucalyptus seed capsule galls could be assigned a role (parasitoid, gall former or inquiline) in the gall-inhabiting complex.

Leptocybe invasa, the blue gum chalcid, is a well-known pest of Eucalyptus. Since it was first noticed in the Mediterranean and Middle East in 2000, it has spread to other Eucalyptus growing countries around the world. Efforts to control it have included the release of a number of larval and pupal parasitoids. This Report Note serves as the first record of the presence of Quadrastichus mendeli in South Africa, a parasitoid originally released as a biological control agent of L. invasa in Israel. The interactions and potential impacts on the other insects in the L. invasa galls will need to be investigated.

No abstract

Selitrichodes neseri Kelly & La Salle n. sp. (Hymenoptera: Eulophidae: Tetrastichinae), is described as a parasitoid of the inva-sive eucalyptus gall wasp Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae: Tetrastichinae), which is causingsubstantial damage particularly in commercial Eucalyptus plantations. Selitrichodes neseri was originally collected in Australiain 2010 when searching for biological control agents of L. invasa. It has since been reared in quarantine in South Africa where it is being evaluated for release as a biological control agent of L. invasa.

No abstract