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Brevibacillus laterosporus is a globally ubiquitous, spore forming bacterium, strains of which have shown toxic activity against invertebrates and microbes and several have been patented due to their commercial potential. Relatively little is known about this bacterium. Here, we examined the genomes of six published and five newly determined genomes of B. laterosporus, with an emphasis on the relationships between known and putative toxin encoding genes, as well as the phylogenetic relationships between strains. Phylogenetically, strain relationships are similar using average nucleotide identity (ANI) values and multi-gene approaches, although PacBio sequencing revealed multiple copies of the 16S rDNA gene which lessened utility at the strain level. Based on ANI values, the New Zealand isolates were distant from other isolates and may represent a new species. While all of the genomes examined shared some putative toxicity or virulence related proteins, many specific genes were only present in a subset of strains., Highlights • We examined genomes of 11 Brevibacillus laterosporus, a bacterium which is antagonistic to invertebrates and/or microbes • Multiple phylogenetic methods showed New Zealand isolates more distant than all other isolates • Each genome could contain 11–13 copies of the 16S rDNA gene, some of which were not identical • Many putative toxin encoding genes were present in the genomes, but the toxin complement varied from isolate to isolate • Variation in occurrence of toxin-encoding genes indicates the potential to find strains with new combinations of activities

The advance of no-till management systems in agriculture favored the increase of Diloboderus abderus (Sturm) populations in most of the cultivated areas in South America. Damage to wheat crops (Triticum aestivum Linnaeus) is caused by the larvae, commonly known as white grubs, which consume seeds and roots, weakening or killing the plants. Entomopathogenic nematodes (EPNs) are insect parasites usually used as biological control agents of larvae of Scarabaeidae species. However, a great variability in pathogenicity and virulence against different white grubs has been observed among EPN species and isolates of a single species. The aim of this work was to evaluate the pathogenicity of Steinernema rarum (de Doucet) CUL isolate, Heterorhabditis bacteriophora (Poinar) SMC isolate and their symbiotic bacteria against D. abderus larvae. Wheat plants were grown in plastic pots under greenhouse conditions and one larva (L1, L2 or L3) of D. abderus was placed in each pot and then inoculated with 1000 EPN IJs. H. bacteriophora caused 95 and 45% mortality to L1 and L2, respectively. No L3 mortality caused by the studied isolates was observed. Field experiments were conducted in wheat plots in 2013 and 2014. Treatments consisted of surface application of S. rarum or H. bacteriophora (2.5 × 109 IJs/ha) and chlorpyrifos; control treatments contained only distilled water. Evaluations were made at day 0, 30 and 60 after treatments by randomly selecting eight sites from each plot and determining the number of D. abderus L2. Larval populations were reduced in plots treated with H. bacteriophora and chlorpyrifos. Larval populations were reduced in plots treated with H. bacteriophora and chlorpyrifos. The plots treated with S. rarum did not show differences in the insect population with respect to the control. EPN symbiotic bacteria were injected into the hemocoel of each larval stage to determine virulence against D. abderus. D. abderus larval mortality caused by symbiotic bacteria was significantly influenced by bacterial concentration and larval stage. H. bacteriophora showed a greater reproductive capacity than S. rarum. We conclude that H. bacteriophora SMC have potential for use as biological control agents of D. abderus first and second-instar larvae. Fil: del Valle, Eleodoro Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina Fil: Frizzo, Laureano Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina Fil: Lax, Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina Fil: Bonora, José Sebastián. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina Fil: Palma, Leopoldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Bernardi Desch, Nahuel Pablo. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina Fil: Pietrobón, Marianela. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina Fil: Doucet, Marcelo Edmundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina