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The search for effective biological control agents without harmful non-target effects has been constrained by the use of impractical (field direct observation) or imprecise (cage experiments) methods. While advances in the DNA sequencing methods, more specifically the development of high-throughput sequencing (HTS), have been quickly incorporated in biodiversity surveys, they have been slow to be adopted to determine arthropod prey range, predation rate and food web structure, and critical information to evaluate the effectiveness and safety of a biological control agent candidate. The lack of knowledge on how HTS methods could be applied by ecological entomologists constitutes part of the problem, although the lack of expertise and the high cost of the analysis also are important limiting factors. In this review, we describe how the latest HTS methods of metabarcoding and Lazaro, a method to identify prey by mapping unassembled shotgun reads, can serve biological control research, showing both their power and limitations. We explain how they work to determine prey range and also how their data can be used to estimate predation rates and subsequently be translated into food webs of natural enemy and prey populations helping to elucidate their role in the community. We present a brief history of prey detection through molecular gut content analysis and also the attempts to develop a more precise formula to estimate predation rates, a problem that still remains. We focused on arthropods in agricultural ecosystems, but most of what is covered here can be applied to natural systems and non-arthropod biological control candidates as well.

The advent of NGS-based methods has been profoundly transforming entomological research. Through continual development and improvement of different methods and sequencing platforms, NGS has promoted mass elucidation of partial or whole genetic materials associated with beneficial insects, pests (of agriculture, forestry and animal, and human health), and species of conservation concern, helping to unravel ecological and evolutionary mechanisms and characterizing survival, trophic interactions, and dispersal. It is shifting the scale of biodiversity and environmental analyses from individuals and biodiversity indicator species to the large-scale study of communities and ecosystems using bulk samples of species or a mixed “soup” of environmental DNA. As the NGS-based methods have become more affordable, complexity demystified, and specificity and sensitivity proven, their use in entomological research has spread widely. This article presents several examples on how NGS-based methods have been used in entomology to provide incentives to apply them when appropriate and to open our minds to the expected advances in entomology that are yet to come.

Knockdown resistance (kdr) and super-kdr (skdr) point mutations have been identified in the voltage-gated sodium channel (vgsc) para genes in several aphid species with resistance to pyrethroids, but have not been confirmed in Aphis glycines Matsumura (Hemiptera: Aphididae), a serious soybean crop pest with resistance to pyrethroids. We used the A. glycines genome assembly GenBank accession number VYZN00000000 to mine potential vgsc para-ortholog genes, and amplicon-seq to screen for kdr and skdr mutations in nine populations from North Central USA with different pyrethroid susceptibility, sampled in 2018-2019. As was found in other aphids, two putative vgsc genes (vgsc1 and vgsc2) were identified in the same scaffold, oriented in opposite directions ~4 kb distant from each other. The vgsc1 gene coded heterodimer 1 (AglNav1) containing the VGSC domains I and II, while vgsc2 coded heterodimer 2 (AglNav2) with domains III and IV. Three splice variants were identified for each vgsc gene. The mutations M918L (skdr), M918I and L925M were identified in domain II in the IIS4-IIS5 linker region, and mutation L1014F (kdr) in the IIS6 segment. Although all mutations were found as heterozygotes, the population with the single M918L mutation and most populations with multiple mutations (M918I+L1014F or L925M+L1014F) exhibited a pyrethroid resistance phenotype, confirmed by λ-cyhalothrin exposure bioassays. The kdr and skdr point mutations in soybean aphid are the same point mutations associated with the target site insensitivity to pyrethroids in other arthropods and very likely contribute to resistance in soybean aphid.

Since welding is one of the most harmful activities in industry, robots and mechanised systems in this process are widely used. As a result, researches about autonomous and semi-autonomous welding systems become extremely important in the quest to reduce losses and improve welding quality. This paper contributes to the velocity control of the displacement module of a linear semi-autonomous welding mechanised system. We propose to use a pole placement control (PPC), which has a simple structure state feedback controller based on poles allocation, which can be applied on low-cost control platforms and use a reduced set of sensors. Experimental results, tested on a Bug-O Modular Drive System, are presented to discuss the feasibility of the proposed control strategy.