Seasonal dynamics of dominant species of soil predators (Coleoptera: Carabidae, Staphylinidae) in agrolandscapes and their potential gluttony

We studied the seasonal change in the number of dominant species of predatory beetles on vegetable crops and determined their potential gluttony. A total of 1,472 beetles were collected, belonging to 22 species of ground beetles (Carabidae) and 27 species of rove beetles (Staphylinidae). The dominant species are: Harpalus rufipes (De Geer, 1774) (17.6% dominance), Amara fulva (De Geer) (13.28%), Bembidion properans (Stephens, 1828) (10.39%), Trechus quadristriatus (Schrank, 1781) (6.20%), Calathus melanocephalus (Linnaeus, 1758) (5.39%), Poecilus cupreus Linnaeus, 1758 (5.3%), Bembidion femoratum Sturm, 1825 (5.10%), Aleochara bilineata, (Gyllenhaal, 1810) (17.6%), Aloconota gregagia (Erichson, 1839) (10.21%), Amischa analis (Gravenhorst, 1802) (6.01%), Amischa bifoveotata (Mannerheim, 1830) (5.41%). During the season, there is a change in dominant species. At the beginning of the season, smaller species dominate, while larger species dominate in the second half of the plant vegetation. The maximum number of predators are observed in June and August. The periods of the maximum abundance of ground beetles and rove beetles do not coincide in time, which is the evolutionary adaptation of two groups of predators that coexist. In laboratory experiments, when pest eggs were offered as food, Aleochara bilineata and Bembidion femoratum were the most voracious. Larger predator species showed high voracity when larvae of flies were offered as food.

Genomic resources forGoniozus legneri,Aleochara bilineataandPaykullia maculata, representing three independent origins of the parasitoid lifestyle in insects

Parasitoid insects are important model systems for a multitude of biological research topics and widely used as biological control agents against insect pests. While the parasitoid lifestyle has evolved numerous times in different insect groups, research has focused almost exclusively on Hymenoptera from the parasitica clade. The genomes of several members of this group have been sequenced, but no genomic resources are available from any of the other, independent evolutionary origins of the parasitoid lifestyle. Our aim here was to develop genomic resources for three parasitoid insects outside the parasitica. We present draft genome assemblies forGoniozus legneri, a parasitoid Hymenopteran more closely related to the non-parasitoid wasps and bees than to the parasitica wasps, the Coleopteran parasitoidAleochara bilineataand the Dipteran parasitoidPaykullia maculata.The genome assemblies are fragmented, but complete in terms of gene content. We also provide preliminary structural annotations. We anticipate that these genomic resources will be valuable for testing the generality of findings obtained from parasitica wasps in future comparative studies.Data availabilityThe Whole Genome Shotgun projects have been deposited at DDBJ/ENA/GenBank under the accessions NCVS00000000 (G. legneri), NBZA00000000 (A. bilineata) and NDXZ00000000 (P. maculata).The versions described in this paper are versions NCVS01000000, NBZA01000000 and NDXZ01000000, respectively. Mapped reads and genome annotations are available throughhttp://parasitoids.labs.vu.nl/parasitoids/. This website also includes genome browsers and viroblast instances for each genome.

Spring emergence of Canadian Delia radicum and synchronization with its natural enemy, Aleochara bilineata

To characterize time of spring emergence following post-diapause development, Delia radicum (L.) (Diptera: Anthomyiidae) from Saskatchewan, Manitoba, and southwestern Ontario were collected in fall, maintained over winter at 1 °C, then transferred to higher constant temperatures until adult emergence. At each location there were “early” and “late” phenotypes. Truncated normal models of temperature dependency of development rate were fitted for each phenotype from each location. We provide the first evidence of geographic variation in the criteria separating these phenotypes. Separation criteria and models for early and late phenotypes at the two prairie locations, approximately 700 km apart, were indistinguishable, but differed from those for Ontario. Prairie phenotypes developed more slowly than Ontario phenotypes, and more prairie individuals were of the late phenotype. Poor synchronization of spring emergence could impair predation of D. radicum eggs by adult Aleochara bilineata Gyllenhal (Coleoptera: Staphylinidae). Aleochara bilineata from Manitoba were reared and development rates modelled as for D. radicum. Models of development rates for the two species, when combined with simulated soil temperatures for two prairie locations, suggest that emergence of adult A. bilineata is well synchronized with availability of D. radicum eggs in prairie canola.