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The objective of this study was to assess barcoding of environmental DNA as a method for monitoring invertebrate ecosystem service providers in soil samples.We selected 26 invertebrate ecosystem service providers that occur in New Zealand kiwifruit or apple orchards and produced mitochondrial cytochrome c oxidase gene subunit I (cytochrome oxidase I) and/or 28S ribosomal DNA sequences for each. Specific barcode primers were designed for each invertebrate ecosystem service provider and tested, along with generic barcoding cytochrome oxidase I primers, for their ability to detect DNA from invertebrate ecosystem service providers that had been added to sterilized and unsterilized soil samples.Although the specific primers accurately detected the invertebrate ecosystem service providers in more than 96% of the samples, the generic cytochrome oxidase I primers detected only 37% of the invertebrate ecosystem service providers added to the sterilized samples and 2.5% in the unsterilized samples.In a field test, we compared metabarcoding with traditional invertebrate trapping methods to detect the invertebrate ecosystem service providers in 10 kiwifruit and 10 apple orchards. All invertebrate ecosystem service providers were collected in traps in at least one orchard, but very few were identified by metabarcoding of soil environmental DNA.Although the specific primers can be used as a tool for monitoring invertebrate ecosystem service providers in soil samples, methodological improvements are needed before metabarcoding of soil environmental DNA can be used to monitor these taxa. [ABSTRACT FROM AUTHOR]

Abstract: Invertebrates are important providers of ecosystem services to orchards and the orchards may benefit where there is greater biodiversity. Previous research has shown that apple orchards using organic or integrated pest management support different invertebrate communities, as can different orchards within the same management system. In the present study, we examined the potential for agrichemical usage to explain inter‐orchard invertebrate community differences in 10 New Zealand apple orchards under integrated pest management. Multiple regression models were used to examine relationships between spray diary data and invertebrates collected by branch tapping, pitfall and sticky traps in 2011/2012. Insecticides, fungicides, plant growth regulators and fertilizers were used as explanatory variables in these models and the most parsimonious models were identified. Plant growth regulators were significant in most of the models for inter‐orchard variability in total invertebrate diversity. Insecticides featured strongly in models explaining pest assemblages, although not so strongly for models for their natural enemies. Fungicide and fertilizer use featured in models explaining communities of decomposers and fungivores. The results generated several hypotheses about the impacts of specific agrichemicals on invertebrate biodiversity, which, if tested, could establish the feasibility of customizing spray schedules to meet both biodiversity and production goals. [ABSTRACT FROM AUTHOR]

1 Increasing the biodiversity of agro-ecosystems may benefit rare and native species, improve ecosystem services and increase grower incomes through higher value eco-verified orchard products. Previous research has shown that the taxonomic richness of invertebrates in organic kiwifruit orchards is significantly higher than in integrated pest management (IPM) orchards, suggesting that orchard management practices may affect invertebrate biodiversity. 2 We used multiple regression models to investigate the relationships between the diversity of ground-active invertebrates in three functional groups [natural enemies, herbivores, detritivores (including fungivores)] and 14 management practices used on 10 organic and 10 IPM orchards. 3 The significant relationships between the management variables and invertebrate communities differed for each functional group: (i) the greater diversity of natural enemy and detritivore taxa in organic orchards was significantly correlated with less toxic agrichemical sprays; (ii) greater amounts of vegetative ground cover in the organic orchards was significantly correlated with a greater diversity of detritivore and herbivore taxa; and (iii) differences in magnesium application rates explained some of the variation in the herbivore and detritivore communities. 4 Management practices on IPM kiwifruit orchards could be altered to increase invertebrate biodiversity, which also may improve ecosystem services on these orchards; however, care should be taken to ensure that pest populations do not also benefit from these changes. [ABSTRACT FROM AUTHOR]