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Recent advances in gene-editing technologies have opened new avenues for genetic pest control strategies, in particular around the use of gene drives to suppress or modify pest populations. Significant uncertainty, however, surrounds the applicability of these strategies to novel target species, their efficacy in natural populations and their eventual safety and acceptability as control methods. In this article, we identify issues associated with the potential use of gene drives in agricultural systems, to control pests and diseases that impose a significant cost to agriculture around the world. We first review the need for innovative approaches and provide an overview of the most relevant biological and ecological traits of agricultural pests that could impact the outcome of gene drive approaches. We then describe the specific challenges associated with using gene drives in agricultural systems, as well as the opportunities that these environments may offer, focusing in particular on the advantages of high-threshold gene drives. Overall, we aim to provide a comprehensive view of the potential opportunities and the remaining uncertainties around the use of gene drives in agricultural systems.

Important agricultural technologies do not always reach smallholder farmers at the pace required to improve production. The Syngenta Foundation for Sustainable Agriculture's farmers' hubs is designed to improve access to new technologies. We describe how these businesses fit into the innovation system of Bangladesh and document what products and services are being provided to the community. We surveyed 300 farmers who were participants or non-participants living near six study hubs. The most used service (97 per cent or participants) was seedlings grown in specialised soil less media, which is a product supported through their research mechanism and where there are few alternatives in the market. However, other services like farm machinery, and purchasing of produce were less well used by participants. The location of the farmers' hubs in smaller communities can enhance these farmers' access to certain information and technology. [ABSTRACT FROM AUTHOR]

Encarsia sophia Girault and Dodd and Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) are important biological control agents of Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) because of their outstanding parasitic and destructive host-feeding ability. This study evaluated their parasitism and host-feeding capacity at five B. tabaci SSA1 host densities (10, 40, 60, 100 and 140) on three cassava genotypes (Alado alado, NAROCASS 1 and NASE 14) in the screenhouse. The results revealed that host density and parasitoid species had significant effects (P < 0.001) on host feeding and parasitism of B. tabaci SSA1, while cassava genotype had no effect (P > 0.05). Both E. mundus and E. sophia females killed more hosts by parasitism and host feeding with increased host density; E. mundus parasitised 1.5 and 40.2 nymphs at host density of 10 and 140 nymphs, respectively. At all host densities, E. sophia killed more hosts by feeding while E. mundus parasitised more hosts. However, E. mundus caused more total nymph death than E. sophia at all host densities. At a host density of 100 nymphs, E. mundus killed 38.9 nymphs compared to the 22.4 nymphs killed by E. sophia. In conclusion, the two parasitoids had a density-dependent relationship with the host, irrespective of species which bodes well for biological control programs. Thus, the deployment of these hymenopteran parasitoids in areas with high B. tabaci SSA1 populations through augmentative release would offer commendable pest population suppression. The interaction of cassava genotype with parasitoid species improved biocontrol efficiency, hence as long as a glabrous cassava genotype is planted, efficacy is enhanced. [ABSTRACT FROM AUTHOR]

Management of agricultural pests requires an understanding of pest species diversity, their interactions with beneficial insects and spatial‐temporal patterns of pest abundance. Invasive and agriculturally important insect pests can build up very high populations, especially in cropping landscapes. Traditionally, sampling effort for species identification involves small sample sizes and is labour intensive. Here, we describe a multiprimer high throughput sequencing (HTS) metabarcoding method and associated analytical workflow for a rapid, intensive, high‐volume survey of pest species compositions. We demonstrate our method using the taxonomically challenging Bemisia pest cryptic species complex as examples. The whiteflies Bemisia including the"tabaci" species are agriculturally important capable of vectoring diverse plant viruses that cause diseases and crop losses. Our multiprimer metabarcoding HTS amplicon approach simultaneously process high volumes of whitefly individuals, with efficiency to detect rare (i.e., 1%) test‐species, while our improved whitefly primers for metabarcoding also detected beneficial hymenopteran parasitoid species from whitefly nymphs. Field‐testing our redesigned Bemisia metabarcoding primer sets across the Tanzania, Uganda and Malawi cassava cultivation landscapes, we identified the sub‐Saharan Africa 1 Bemisia putative species as the dominant pest species, with other cryptic Bemisia species being detected at various abundances. We also provide evidence that Bemisia species compositions can be affected by host crops and sampling techniques that target either nymphs or adults. Our multiprimer HTS metabarcoding method incorporated two overlapping amplicons of 472 bp and 518 bp that spanned the entire 657 bp 3' barcoding region for Bemisia, and is particularly suitable to molecular diagnostic surveys of this highly cryptic insect pest species complex that also typically exhibited high population densities in heavy crop infestation episodes. Our approach can be adopted to understand species biodiversity across landscapes, with broad implications for improving transboundary biosecurity preparedness, thus contributing to molecular ecological knowledge and the development of control strategies for high‐density, cryptic, pest‐species complexes. [ABSTRACT FROM AUTHOR]

Earwigs have been observed as an irregular pest of increasing concern to farmers growing canola and other winter grain crops in Australia over the past decade. In this study, we tested how abiotic and biotic factors influence the feeding behaviour of earwigs. Studies were conducted with two Australian native species, Labidura truncata and Nala lividipes, and the introduced European earwig, Forficula auricularia. We constructed field‐based exclusion plots that prevented F. auricularia from moving in or out of a small area of canola. We monitored F. auricularia activity and the feeding damage to canola plants throughout the winter growing season. In the laboratory, we established microcosms containing crop seedlings, as well as aphids as an alternate food source, to examine the feeding behaviour of all three species. The native earwigs L. truncata and N. lividipes did not cause feeding damage to canola or wheat but were found to actively consume aphids when present. We conclude that these species are unlikely to cause significant (economic levels) of pest damage in a field environment. In the microcosm trial, F. auricularia caused considerable damage to canola seedlings and readily consumed aphids. Forficula auricularia also caused feeding damage to canola seedlings early in the winter growing season in the field trial. However, by the end of the season, F. auricularia presence was associated with increased canola biomass. Furthermore, F. auricularia did not damage canola until all nearby aphids were consumed. Together, our field and laboratory studies suggest F. auricularia can be an important predator of aphid pests in canola, indicating a dual role of this species as both a pest and a beneficial species in winter grain systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: The European earwig, Forficula auricularia (L.) (Dermaptera: Forficulidae), is regarded as an important beneficial in many orchard environments but has the potential to be a plant pest in other systems, including to grain crops. Due to its agricultural importance, the lifecycle of F. auricularia has been widely studied in North America and Europe. However, much less is known in the southern hemisphere, including Australia where F. auricularia has been present for over 170 years. RESULTS: To elucidate the lifecycle of F. auricularia, we monitored five sites in grain-growing areas of southern Australia using two different trap types. Adults were found year-round, but most prevalent from late-spring to mid-winter. First instars were typically found from mid to late winter. Second, third and fourth instars occurred from winter through to late spring. The seasonal development of F. auricularia in Australia may be much earlier than observed in comparable North American studies. Degree day modelling highlights variation in development times across the active season for F. auricularia across our sites. CONCLUSION: Forficula auricularia is well adapted to the Australian grain growing environments. The timing of egg hatching aligns closely with crop emergence, juveniles then develop alongside the crop, and adult development occurs by harvest time in late spring. These findings are important given that many of these crops (canola, lucerne, pulses) are vulnerable to attack by F. auricularia during emergence and development. They also suggest a phenotypic capacity of this species to adapt different phenology after introduction into a novel environment. [ABSTRACT FROM AUTHOR]