NARDI FUNDULEA, ROMANIA ROMANIAN AGRICULTURAL RESEARCH, NO. 34, 2017 www.incda-fundulea.ro Print ISSN 1222-4227; Online ISSN 2067-5720 EFFECTS OF MAIZE EXPRESSING THE INSECTICIDAL PROTEIN CRY1AB ON NON-TARGET GROUND BEETLE ASSEMBLAGES (COLEOPTERA, CARABIDAE) Jacek Piotr Twardowski1*, Paweł Bereś2, Michał Hurej1, Zdzisław Klukowski1, Roman Warzecha3 1Department of Plant Protection, Wrocław University of Environmental and Life Sciences, Grunwaldzki 24a, 50-363 Wrocław, Poland. 2Institute of Plant Protection - National Research Institute, Langiewicza 28, 35-101 Rzeszów, Poland. 3Plant Breeding and Acclimatization Institute - National Research Institute Radzików, 05-870 Blonie, Poland. *Corresponding author. E-mail: [email protected] ABSTRACT Ground beetle fauna, as well-known worldwide bioindicators, were studied in the large-scale Bt maize experiment in Poland. The aim of this study was to determine the impact of the Bt maize variety in comparison to conventional plants on species from ground beetle assemblages (Coleoptera: Carabidae) as non-target arthropods. A genetically modified Bt maize variety (DKC 3421 Yield Gard®, event MON 810) and its near-isogenic DKC 3420 (unsprayed and sprayed with a lambda-cyhalotrine insecticide) were cultivated at 2 locations: Budziszów, near Wrocław in south-western Poland, and in Głuchów, near Rzeszów in the south-eastern region, in 2008-2010. For comparative analysis two additional non-Bt varieties (Bosman and Wigo) were also included. To monitor population density of ground beetles, 80 pitfall traps were used at each location. Comparisons showed no significant differences between abundance and diversity patterns of ground beetles for the Bt maize, the near isoline and two local varieties. Some minor differences were with no clear tendencies related to Bt maize. Key words: bioindicators, Bt maize, epigeal arthropods, environmental risk, transgenic crops. INTRODUCTION Ostrinia nubilalis (Bereś, 2010). In plant protection this prevents economic loss doption of transgenic crops should throughout the season, consequently A always be supported by widespread eliminating the requirement for extensive assessment of ecological risk with potential monitoring and insecticide application against adverse effects on non-target arthropods caterpillars. Bt maize has been grown affecting the biodiversity of agro-ecosystems commercially since 1996 (United States), and (Hilback et al., 2009; Hui-Lin et al., 2011; from this time the area under such GM Naranjo, 2009). The gene expressing delta- varieties rapidly increased worldwide (Meissle endotoxin Cry 1Ab from Bacillus thuringensis et al., 2009). Berliner var. kurstaki is usually used only Ground beetles are one of the key against well-defined caterpillars from organisms in maize field ecosystem, often lepidopteran order that feed on maize. In acting as generalist predators of many crop Europe, the most important pest species pests (Holland, 2002; Lang et al., 1999; Lopez are the European corn borer (Ostrinia et al., 2005). These soil-dwelling insects are nubilalis Hübner, Crambidae) and, in the exposed to Bt proteins directly through Mediterranean Basin, pink stem borer ingesting maize litter and pollen, and indirectly (Sesamia nonagrioides Lefëbvre, Noctuidae) through eating prey that feeds on Bt maize (Meissle et al., 2014). One of the strategies to plants. They can also act as natural enemies of control maize borers is to cultivate genetically pests feeding on maize, which is another modified plants (GM). Bt maize expressing possible way of being in contact with the GM- the insecticidal protein Cry1Ab very plant material ingested by the herbivores. In the effectively controls the primary targets, as soil ecosystem, the detection of the ecological ________________________________________ Received January 2016; accepted 7 February 2017. First online: March, 2017. DII 2067-5720 RAR 2017-9 352 Number 34/2017 ROMANIAN AGRICULTURAL RESEARCH consequences of exposure to Bt maize is from 2008 to 2010. A large-scale experiment difficult because sampling is time-consuming was allocated in the region where the majority and there is high variability among samples. of maize is cultivated in Poland, and where The ecological requirements of Carabidae are infestation by the European corn borer is a known and well defined for many species that substantial problem (Bereś, 2010). The form assemblages in cultivated fields, making following treatments were used in the them excellent bioindicators (Koivula, 2011). experiment: (1) Bt transgenic maize (DKC 3421 Moreover, some species can be herbivorous, Yield Gard®, event MON 810), (2) its near- detrivorous or carnivorous, important in isogenic non-Bt variety without insecticide controlling maize pests. Such species can be application (DKC 3420), (3) isogenic non-Bt appropriate for describing the trophic variety (DKC 3420) with lambda-cyhalotrine relationships and degree of biodiversity in the treatment, and for comparative analysis 2 soil. This coleopteran group is also thought to non-Bt conventional varieties (4) Bosman and be an important component of both natural and (5) Wigo sprayed with lambda-cyhalotrine were agricultural ecosystems, contributing to the also included (as reference control Ref. 1 and regulation of prey species and biological Ref. 2, respectively). The reference varieties had control of pests, and even having a role in the similar FAO numbers but were otherwise improvement of physical soil parameters unrelated to the MON 810 and DKC groups. (Symondson et al., 2002; Thiele, 1977). Each year the insecticide (active ingredient: Ground beetles’ contribution to biodiversity, as lambda-cyhalotrine in Karate Zeon 050 CS) they are a species rich arthropod family, also was applied once in selected treatments in the results from the relatively high biomass and 2nd half of July at maize stage BBCH 55-59, in usually high number of species collected in a a dose of 0.2 l/ha. Weed control was done particular area. Thus, soil-dwelling Carabidae with nikosulfuron (Milagro Extra 6 OD), have been identified as good candidates for shortly after maize emergence (in the 2 half evaluating the potential unintended effects of of May), on the entire area of the experiment. transgenic crops (Lopez et al., 2005). This herbicide has low potential for The aim of the study was to determine bioaccumulation, and is not persistent in soil. the impact of the Bt maize variety MON 810, Neither fungicides nor other pesticides were expressing the Cry1Ab protein, aimed at applied. All the agro-technology applied in controlling lepidopteran pests, on abundance the maize field, including fertilizers, was and species composition of non-target ground identical on the entire area of the experiment. beetles (Coleoptera: Carabidae) in comparison The design of this experiment consisted of to conventional maize varieties. Evaluations randomised complete blocks with 5 treatments of the effects of Bt toxin on Carabidae have and 4 replications. For the experimental design been performed as part of broader field studies a large size plot was set up (40 x 40 m). An aimed at determining the effects of GM plants alley distance of 4.5 m was used between on non-target arthropods within the maize 1600 m2 plots. Experiments were conducted ecosystem. on the same plots for 3 consecutive years (in both locations), hence the growing amount of MATERIAL AND METHODS Bt endotoxin we could expect on the same plots. Detailed design and description of the Site properties and study design field experiment was included in Twardowski The direct environmental effects of the et al. (2014). Bt gene were tested through the studies conducted in maize fields at 2 locations in the Ground beetle collection southern part of Poland (central Europe), i.e. in A total of 80 circular pitfall traps were set Budziszów (51°06' N, 17°02' E), near up in each location to collect the epigeal Wrocław, and in Głuchów (50°01″ N, 22°17″ arthropods. 4 traps were arranged on each E), near Rzeszów (distance between locations plot, and the distance between them was at about 400 km), in the three sampling periods least 10 m, with a 10 m distance from plot 353 JACEK PIOTR TWARDOWSKI ET AL.: EFFECTS OF MAIZE EXPRESSING THE INSECTICIDAL PROTEIN CRY1AB ON NON-TARGET GROUND BEETLES ASSEMBLAGES (COLEOPTERA, CARABIDAE) margins. The arrangement of the traps within individuals, S = number of species collected. plots was performed so as to avoid any side- The structure of the ground beetles effects. These were inserted into the ground community was analysed with the use of so that the lip was flush with the soil surface. detrended correspondence analysis (DCA), Each trap was a plastic container with a 9 cm without down-weight of rare species and diameter and 12 cm deep, filled with 50:50 rescaling of the axis. Prior to analysis, species water and ethylene glycol used as a abundance data were log10 (x+1) preservative, and was sunk into another plastic transformed. The software CANOCO, version tube. A square plastic, transparent lid 4.5, was performed for this analysis. protected the trap against precipitation. The traps were emptied weekly from the beginning RESULTS AND DISCUSSION of June (plants with 4-6 leaves) until maize maturation (the 2 half of September). In this Quantitative and qualitative differences period, traps were checked in 7-day intervals in ground beetle assemblages and emptied in the sample container, and later During three years of our study, a huge ground beetles were separated from