We have developed a screening method that can be used during the problem formulation phase of risk assessment to identify and prioritize non-target invertebrates for risk analysis with any transgenic plant. In previously published protocols for this task, five criteria predominated. These criteria have been combined by our method in a simple model which assesses: (1) the possible level of risk presented by the plant to each invertebrate species (through measurements of potential hazard and exposure, the two principal criteria); (2) the hypothetical environmental impact of this risk (determined by the currently known status of the species' population in the ecosystem and its potential resilience to environmental perturbations); (3) the estimated economic, social and cultural value of each species; and (4) the assessed ability to conduct tests with the species. The screening method uses information on each of these criteria entered into a specially designed database that was developed using Microsoft Access 2003. The database holds biological and ecological information for each non-target species, as well as information about the transgenic plant that is the subject of the risk assessment procedure. Each piece of information is then ranked on the basis of the value of the information to each criterion being measured. This ranking system is flexible, allowing the method to be easily adapted for use in any agro-ecosystem and with any plant modification. A model is then used to produce a Priority Ranking of Non-Target Invertebrates (PRONTI) score for each species, which in turn allows the species to be prioritized for risk assessment. As an example, the method was used to prioritize non-target invertebrates for risk assessment of a hypothetical introduction of Bacillus thuringiensis (Bt) Cry1Ac-expressing Pinus radiata trees into New Zealand.
By expressing specific MYB transcription factors in plants, levels of anthocyanins can be raised and new varieties of crops with attractive red or purple foliage, fruits, and flowers can be produced. Insects might respond differently to these plants, and potentially the large‐scale use of such crops could have non‐target impacts on agricultural ecosystems. In this study, larvae of Spodoptera litura (F.) and Helicoverpa armigera (Hübner) (both Lepidoptera: Noctuidae) were fed with red‐pigmented leaves from transgenic tobacco, Nicotiana tabacum L. (Solanaceae) cv. Samsun, plants expressing the AtMYB75/PAP1 transcription factor from Arabidopsis thaliana (L.) Heynh. (Brassicaceae). All of the transgenic plants had elevated concentrations of several anthocyanins and other polyphenolics, including chlorogenic and other caffeic acids, and rutin. Spodoptera litura pupation was significantly delayed and H. armigera larval mortality significantly increased by feeding on the transgenic foliage, compared with controls fed with green non‐transgenic tobacco leaves. When given a choice, H. armigera larvae ate significantly more of the green control leaves than of the red transgenic leaves. The expression of MYB transcription factors to produce novel colours in transgenic crop plants may alter the levels of anthocyanins and other polyphenolic compounds and this could cause species‐specific changes in the feeding behaviour, development, and survival of insects feeding on the plants. Results to date suggest that these impacts will be neutral or negative.
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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.