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Maize is the major staple food in Africa. In developing countries, post-harvest losses due to insect pests are up to 40% of total production. Inert powders can be alternative tools in integrated pest management programs of stored cereals. The aim of this study was to assess the efficacy of ashes from cashew (Anacardium occidentale) branches, charcoal powder, dried and milled Eucalyptus citriodora leaves, and diatomaceous earth (standard check), for Sitophilus oryzae control on stored maize grains. The experimental design was completely randomized with 11 treatments and 4 replications. Insect introduction was carried out immediately after treatment application and at 30 and 60 days after. The mortality assessment was performed by counting the dead insects at 10 and 20 days after each infestation. The emergence of S. oryzae adults was also assessed at three different times. The germination of treated grains was also evaluated. Data analysis was performed on the SISVAR statistical package. Diatomaceous earth showed maximum control efficiency (73.75%) at 10-day evaluation, reaching total control at a 20-day evaluation. The remaining treatment control efficiency was below 50% in all concentrations and evaluations. The lowest insect emergence rates were observed in grains treated with diatomaceous earth or charcoal powder, which were more efficient than cashew ashes, Eucalyptus citriodora, and untreated control. There was no significant effect of the tested products on seed germination so, they can be used in smallholder farmers' grain storage. The results allow us to affirm that Eucalyptus citriodora charcoal powder, and cashew ashes can be used to reduce Sitophilus oryzae damage in traditional agricultural systems. Considering the reduction in the Sitophilus oryzae progeny, the potential use of charcoal powder should be considered, given the efficiency compared to that of the diatomaceous earth. Thus, the plant-derived products tested in this study has the potential to be used in the integrated management of Sitophilus oryzae in stored products. [ABSTRACT FROM AUTHOR]

We consider a massive relativistic particle in the background of a gravitational plane wave. The corresponding Green functions for both spinless and spin-cases, previously computed by Barducci and Giachetti (2005 J. Phys. A: Math. Gen.381615), are reobtained here by alternative methods, as for example, the Fock-Schwinger proper-time method and the algebraic method. In analogy with the electromagnetic case, we show that for a gravitational plane-wave background a semiclassical approach is also sufficient to provide the exact result, though the Lagrangian involved is far from being a quadratic one. [ABSTRACT FROM AUTHOR]

The restoration and recovery of imperiled mussel species will require the re-establishment of populations into historically occupied habitats. The possible existence of genetic differentiation among populations should be considered before inter-basin transfers are made. Eighty individuals of the federal candidate species Lexingtonia dolabelloides were sampled from populations in the North Fork Holston, Middle Fork Holston, Clinch, Paint Rock and Duck rivers of the Tennessee River basin in the southeastern United States. We sequenced 603 base-pairs of a mitochondrial DNA gene (ND-1) and 512 base-pairs of a nuclear DNA gene (ITS-1). Analyses of molecular variation (AMOVA) values for both genes indicated that the majority of variation in L. dolabelloides resided within populations (82.9–88.3%), with 11.7–17.1% of variation among populations. Haplotype frequencies differed significantly among populations for both genes sequenced. Clustering of haplotypes in minimum-spanning networks did not conform stringently to population boundaries, reflecting high within-population and low between-population variability. Maximum parsimony analysis did not identify any population as a monophyletic lineage. A Mantel test showed no significant correlation between geographical stream distance and genetic distance, thus not supporting a pattern of isolation-by-distance. Overall, results provided support to manage fragmented populations of L. dolabelloides in the Tennessee River drainage as two management units (MUs), but did not provide evidence for the existence of ESUs following published molecular criteria. [ABSTRACT FROM AUTHOR]

Wing geometric morphometrics has been applied to honey bees (Apis mellifera) in identification of evolutionary lineages or subspecies and, to a lesser extent, in assessing genetic structure within subspecies. Due to bias in the production of sterile females (workers) in a colony, most studies have used workers leaving the males (drones) as a neglected group. However, considering their importance as reproductive individuals, the use of drones should be incorporated in these analyses in order to better understand diversity patterns and underlying evolutionary processes. Here, we assessed the usefulness of drone wings, as well as the power of wing geometric morphometrics, in capturing the signature of complex evolutionary processes by examining wing shape data, integrated with geographical information, from 711 colonies sampled across the entire distributional range of Apis mellifera iberiensis in Iberia. We compared the genetic patterns reconstructed from spatially-explicit shape variation extracted from wings of both sexes with that previously reported using 383 genome-wide SNPs (single nucleotide polymorphisms). Our results indicate that the spatial structure retrieved from wings of drones and workers was similar (r = 0.93) and congruent with that inferred from SNPs (r = 0.90 for drones; r = 0.87 for workers), corroborating the clinal pattern that has been described for A. m. iberiensis using other genetic markers. In addition to showing that drone wings carry valuable genetic information, this study highlights the capability of wing geometric morphometrics in capturing complex genetic patterns, offering a reliable and low-cost alternative for preliminary estimation of population structure. [ABSTRACT FROM AUTHOR]