Interactions between hymenopteran species associated with gall‐forming wasps : the Leptocybe invasa community as a case study

1. Leptocybe invasa is native to Australia and induces galls on various species of Eucalyptus. Two genetically distinct lineages of this wasp have been detected outside its native range, namely, Leptocybe Lineage A and Leptocybe Lineage B. 2. The parasitoid Selitrichodes neseri was released in South Africa as a biological control agent against L. invasa. Another parasitoid of L. invasa, Quadrastichus mendeli, as well as Megastigmus zebrinus (parasitoid) and Megastigmus pretorianensis (role unknown), have also been recorded emerging from L. invasa galls. The objective of this study was to investigate the interactions between the different hymenopterans associated with L. invasa galls in South Africa. 3. L. invasa galls were dissected and species‐specific primers and restriction enzymes were used to identify the larvae where interactions were noted. 4. S. neseri, Q. mendeli and M. zebrinus were confirmed to parasitize Leptocybe Lineage A, and S. neseri was confirmed to parasitize Leptocybe Lineage B. Furthermore, there were direct interactions between these parasitoids, where parasitoids were found parasitising each other. The gall forming experiment confirmed that M. pretorianensis is not a gall former, but other potential roles remain uncertain.Supporting Information: Table S1. Species specific primers and their annealing temperatures for the hymenopteran species associated with Leptocybe invasa galls and the expected fragment sizes amplified by each species‐specific primer for the region Cyt b. Table S2. The fragment sizes of digested Cyt b amplicons using the AseI restriction enzyme for Leptocybe invasa (A and B), Selitrichodes neseri, Megastigmus zebrinus, Megastigmus pretorianensis and Quadrastichus mendeli.https://onlinelibrary.wiley.com/journal/146195632021-10-13hj2021BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and Entomolog

The distribution and diversity of Leptocybe invasa (Hymenoptera: Eulophidae) and its gall associates in South Africa

Leptocybe invasa is an invasive gall wasp and pest of Eucalyptus trees, which has become widely distributed in Africa, Asia, Europe and the Americas. Several other wasp species have been found to co-occur in L. invasa-induced galls. In South Africa, this includes an introduced biological control agent, Selitrichodes neseri; two known, accidentally introduced parasitoids, Megastigmus zebrinus and Quadrastichus mendeli; and M. pretorianensis, whose role in the gall is uncertain. In addition to the gall associates, a second lineage of L. invasa or cryptic species was discovered in South Africa in 2015. To determine the distribution and prevalence of these species across South Africa, a national monitoring scheme was initiated. Galled Eucalyptus material was collected at infested sites and emerging adults were collected and identified. Morphology, DNA barcoding and polymerase chain reaction (PCR) Restriction Fragment Length Polymorphism analyses were used to differentiate between the species and lineages. Results from the first two sampling periods indicated that L. invasa lineage A has spread throughout South Africa while lineage B had a more limited distribution in the country. Subsequent samples recorded the further spread of L. invasa Lineage B, which now occurs in all provinces sampled. The Leptocybe lineages were found to co-occur on individual trees, increasing the potential for admixture. From the Eucalyptus genotypes sampled, there was no indication of differences in host association between the Leptocybe lineages. Selitrichodes neseri, M. zebrinus and M. pretorianensis were present throughout South Africa and emerged from trees that contained both Leptocybe lineages, but their frequency varied with site. This study will inform future distribution of parasitoids as well as monitoring of potential changes in plant host resistance, admixture and parasitoid resistance in future.The Department of Science and Innovation–National Research Foundation, Centre of Excellence in Plant Health Biotechnology and Forestry South Africa (FSA).http://www.tandfonline.com/loi/tsfs20hj2023BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and Entomolog

On the linear forms of the Schrodinger equation

Generalizing the linearisation procedure used by Dirac and later by L\'evy-Leblond, we derive the first-order non-relativistic wave equations for particles of spin 1 and spin 3/2 starting from the Schrodinger equation

Relativistic wave equations for interacting massive particles with arbitrary half-intreger spins

New formulation of relativistic wave equations (RWE) for massive particles with arbitrary half-integer spins s interacting with external electromagnetic fields are proposed. They are based on wave functions which are irreducible tensors of rank $n ($n=s-\frac12$) antisymmetric w.r.t. n pairs of indices, whose components are bispinors. The form of RWE is straightforward and free of inconsistencies associated with the other approaches to equations describing interacting higher spin particles

The effect of multiple deformations on the formation of ultrafine grained steels

A C-Mn-Nb-Ti steel was deformed by hot torsion to study ultrafine ferrite formation through dynamic strain-induced transformation (DSIT) in conjunction with air cooling. A systematic study was carried out first to evaluate the effect of deformation temperature and prior austenite grain size on the critical strain for ultrafine ferrite formation (&epsilon; C,UFF) through single-pass deformation. Then, multiple deformations in the nonrecrystallization region were used to study the effect of thermomechanical parameters (i.e., strain, deformation temperature, etc.) on &epsilon; C,UFF. The multiple deformations in the nonrecrystallization region significantly reduced &epsilon; C,UFF, although the total equivalent strain for a given thermomechanical condition was higher than that required in single-pass deformation. The current study on a Ni-30Fe austenitic model alloy revealed that laminar microband structures were the key intragranular defects in the austenite for nucleation of ferrite during the hot torsion test. The microbands were refined and overall misorientation angle distribution increased with a decrease in the deformation temperature for a given thermomechanical processing condition. For nonisothermal multipass deformation, there was some contribution to the formation of high-angle microband boundaries from strains at higher temperature, although the strains were not completely additive.<br /

Planck early results. VIII. The all-sky early Sunyaev-Zeldovich cluster sample

We present the first all-sky sample of galaxy clusters detected blindly by the Planck satellite through the Sunyaev-Zeldovich (SZ) effect from its six highest frequencies. This early SZ (ESZ) sample is comprised of 189 candidates, which have a high signal-to-noise ratio ranging from 6 to 29. Its high reliability (purity above 95%) is further ensured by an extensive validation process based on Planck internal quality assessments and by external cross-identification and follow-up observations. Planck provides the first measured SZ signal for about 80% of the 169 previouslyknown ESZ clusters. Planck furthermore releases 30 new cluster candidates, amongst which 20 meet the ESZ signal-to-noise selection criterion. At the submission date, twelve of the 20 ESZ candidates were confirmed as new clusters, with eleven confirmed using XMM-Newton snapshot observations, most of them with disturbed morphologies and low luminosities. The ESZ clusters are mostly at moderate redshifts (86% with z below 0.3) and span more than a decade in mass, up to the rarest and most massive clusters with masses above 1 × 1015 M