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Genetic modification of apple cultivars through cisgenesis can introduce traits, such as disease resistance from wild relatives, quickly and without crossing. This approach was used to generate the cisgenic apple line C44.4.146, a 'Gala Galaxy' carrying the fire blight resistance gene FB_MR5. In contrast to traditionally bred apple cultivars, genetically modified (GM) plants need to undergo a regulatory risk assessment considering unintended effects before approval for commercial release. To determine potential unintended effects of C44.4.146, we assessed major leaf components and effects on the fitness of the decomposers Drosophila melanogaster (fruit fly) and Folsomia candida (collembolan), which were fed a diet amended with powdered apple leaf material. Leaf material of 'Gala Galaxy', several natural 'Gala' mutants, and the unrelated apple cultivar 'Ladina' were used for comparison. The genetic modification did not alter major leaf components and did not adversely affect survival, growth, or fecundity of the two decomposers. Consistent with previous studies with other GM crops, the differences between conventionally bred cultivars were greater than between the GM line and its non-GM wild type. These data provide a baseline for future risk assessments., (Copyright © 2022. Published by Elsevier Inc.)

Previous studies reported adverse effects of genetically engineered maize that produces insecticidal Cry proteins from Bacillus thuringiensis (Bt) on the water flea Daphnia magna. In the current study, effects of flour, leaves, or pollen from stacked Bt maize that contains six Bt proteins (SmartStax) in two plant backgrounds on life table parameters of D. magna were investigated. Adverse effects were observed for Bt maize flour, originating from different production fields and years, but not for leaves or pollen, produced from plants grown concurrently in a glasshouse. Because leaves contained eight to ten times more Cry protein than flour, the effects of the flour were probably not caused by the Cry proteins, but by compositional differences between the plant backgrounds. Furthermore, considering the natural range of variation in the response of D. magna to conventional maize lines, the observed effects of Bt maize flour were unlikely to be of biological relevance. Our study demonstrates how Cry protein effects can be separated from plant background effects in non-target studies using Bt plant material as the test substance and how detected effects can be judged for their biological relevance., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Non-target effects of genetically engineered (GE) plants on aquatic Daphnia magna have been studied by feeding the species with different maize materials containing insecticidal Cry proteins from Bacillus thuringiensis (Bt). The results of those studies were often difficult to interpret, because only one GE plant was compared to one related non-GE control. In such a setting, effects of the Cry proteins cannot be distinguished from plant background effects, in particular when the test species is nutritionally stressed. In the present study, we tested the suitability of three different maize materials, i.e., flour, leaves and pollen, from five diverse non-GE maize lines (including EXP 258, a breeding line that is closely related to a SmartStax Bt maize) as exclusive food sources for D. magna. The parameters recorded included survival, sublethal endpoints such as body size, number of moltings to first offspring, time to first offspring, number of individuals in first clutch, total number of clutches, total number of offspring, average number of offspring per clutch, and population measures such as net reproductive rate R 0 , generation time T and intrinsic rate of increase r m . The results showed that D. magna can survive, grow and reproduce when fed only maize materials, although the performance was poorer than when fed algae, which indicates nutritional stress. Large differences in life table and population parameters of D. magna were observed among the different maize lines. Our results suggest that confounding effects caused by nutritional stress and plant background might explain some of the conflicting results previously published on the effects of Bt crops on D. magna. Using 95% confidence intervals for the means of the five maize lines for all measured parameters of D. magna performance in our study, we captured the natural range of variation. This information is useful for the interpretation of observed differences in D. magna performance between a GE plant and its non-GE comparator as it helps judging whether observed effects are of biological relevance. If differences between a GE and comparator line are observed and their biological relevance needs to be assessed in future risk assessments of GE maize, 1) the data on natural variation of the different parameters generated by previous studies can be informative (e.g. data from our study for maize fed D. magna); 2) for additional experiments the inclusion of multiple unrelated non-GE comparators should be considered; In addition, it should be taken into account that nutritional stress can affect the outcome of the study., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Trichopria drosophilae (Perkins) (Hymenoptera: Diapriidae) is a pupal parasitoid of drosophila flies recorded from several parts of the world. It is currently considered for augmentative biological programs to control the severe agricultural pest Drosophila suzukii (Matsumura) (Diptera: Drosophilidae). Since D. suzukii has invaded regions that experience zero and sub-zero winter temperatures, cold tolerance of the parasitoid is an important aspect to consider. We characterized low temperature tolerance and overwintering capacity of a colony of T. drosophilae collected in Northern Switzerland. We used copper-constantan thermocouples to determine the supercooling point and pre-freeze mortality. Moreover, we subjected honey-fed and unfed adult T. drosophilae as well as developing stages within their drosophila host to short- and long-term acclimation conditions and assessed the duration of their survival at low temperatures. Finally, we exposed adult and sub-adult stages to winter conditions in a semi-field experiment and evaluated their survival. We found that T. drosophilae is chill susceptible like D. suzukii, but adults froze and survived at colder temperatures than those reported for D. suzukii. Adult parasitoids could tolerate several days of exposure to sub-zero temperatures and could reproduce afterwards, whereas sub-adult stages could survive longer periods under these conditions. The provision of honey and water enhanced the survival of adults and long-term acclimation led to longer survival in all stages. The semi-field experiment supported the results of the laboratory tests. Based on these results we suggest that in Central Europe, T. drosophilae survives winters mainly in developing stages but adults are likely able to tolerate short periods of low spring temperatures., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The transgenic rice line T1C-19 provides high resistance to lepidopteran pests because of the synthesis of the Bacillus thuringiensis (Bt) insecticidal protein Cry1C. It thus shows good prospect for commercial planting in China. Species of Cladocera, an order of aquatic arthropods commonly found in aquatic ecosystems such as rice paddies, might be exposed to the insecticidal protein released from Bt-transgenic rice-straw residues. For the study reported herein, we used Daphnia magna (water flea) as a representative of Cladocera to evaluate whether aquatic arthropods are adversely affected when exposed to Bt rice-straw leachates. We exposed D. magna to M4 medium containing various volume percentages of medium that had been incubated with T1C-19 rice straw or rice straw from its non-transformed near-isoline Minghui 63 (MH63) for 21 days. Compared with pure M4 medium (control), the fitness and developmental and reproduction parameters of D. magna decreased significantly when exposed to rice-straw leachates; conversely, no significant differences between the T1C-19 and MH63 rice-straw leachate treatments were observed, indicating that the Bt rice straw leachate did not adversely affect this non-target species., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Cry1C is a Bacillus thuringiensis (Bt) insecticidal protein and it can be produced by transgenic rice lines developed in China. Cladocera species are common aquatic arthropods that may be exposed to insecticidal proteins produced in Bt-transgenic plants through ingestion of pollen or crop residues in water. As the cladoceran Daphnia magna plays an important role in the aquatic food chain, it is important to assess the possible effects of Bt crops to this species. To evaluate the safety of the Cry1C protein for D. magna, individuals were exposed to different concentrations of purified Cry1C protein in M4 medium for 21 days. Potassium dichromate (K 2 Cr 2 O 7 ), a known toxicant to D. magna, was added to M4 medium as a positive control treatment, and pure M4 medium was used as a negative control. Our results show that developmental, reproductive, and biochemical parameters of D. magna were not significantly different between Cry1C and negative control treatments but were significantly inhibited by the positive control. We thus conclude that D. magna is insensitive to Cry1C., (Copyright © 2017 Elsevier Inc. All rights reserved.)

There is increasing evidence that insecticidal transgenic crops can indirectly cause detrimental effects on arthropod predators or parasitoids when they prey on or parasitize sublethally affected herbivores. Our studies revealed that Chrysoperla carnea is negatively affected when fed Bt-susceptible but not Cry1Ac-resistant Helicoverpa armigera larvae that had fed Bt-transgenic cotton expressing Cry1Ac. This despite the fact that the predators ingested 3.5 times more Cry1Ac when consuming the resistant caterpillars. In order to detect potential differences in the nutrient composition of prey larvae, we evaluated the glycogen and lipid content plus the sugar and free amino acid content and composition of caterpillars fed non-Bt and Bt cotton. The only change in susceptible H. armigera larvae attributable to Bt cotton feeding were changes in sugar concentration and composition. In case of the Cry1Ac-resistant H. armigera strain, feeding on Bt cotton resulted in a reduced glycogen content in the caterpillars. The predators, however, appeared to compensate for the reduced carbohydrate content of the prey by increasing biomass uptake which caused an excess intake of the other analyzed nutritional compounds. Our study clearly proves that nutritional prey-quality factors other then the Bt protein underlie the observed negative effects when C. carnea larvae are fed with Bt cotton-fed prey. Possible factors were an altered sugar composition or fitness costs associated with the excess intake of other nutrients., (Copyright 2010 Elsevier Ltd. All rights reserved.)

We investigated the use of maize pollen as food by adult Chrysoperla carnea under laboratory and field conditions. Exposure of the insects to insecticidal Cry proteins from Bacillus thuringiensis (Bt) contained in pollen of transgenic maize was also assessed. Female C. carnea were most abundant in a maize field when the majority of plants were flowering and fresh pollen was abundant. Field-collected females contained an average of approximately 5000 maize pollen grains in their gut at the peak of pollen shedding. Comparable numbers were found in females fed ad libitum maize pollen in the laboratory. Maize pollen is readily used by C. carnea adults. When provided with a carbohydrate source, it allowed the insects to reach their full reproductive potential. Maize pollen was digested mainly in the insect's mid- and hindgut. When Bt maize pollen passed though the gut of C. carnea, 61% of Cry1Ab (event Bt176) and 79% of Cry3Bb1 (event MON 88017) was digested. The results demonstrate that maize pollen is a suitable food source for C. carnea. Even though the pollen grains are not fully digested, the insects are exposed to transgenic insecticidal proteins that are contained in the pollen., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Like honey bees (Apis mellifera), non-Apis bees could exploit honeydew as a carbohydrate source. In addition to providing carbohydrates, this may expose them to potentially harmful plant products secreted in honeydew. However, knowledge on honeydew feeding by solitary bees is very scarce. Here we determine whether the polylectic solitary bee Osmia bicornis (=O. rufa) collects honeydew under semi-field conditions, and whether this is affected by aphid species and presence of floral nectar. Bees were provided with oilseed rape plants containing flowers and/or colonies of either Myzus persicae or Brevicoryne brassicae. We used the total sugar level of the bee crop as a measure of the individual's nutritional state and the oligosaccharide erlose as indicator for honeydew consumption. Erlose was present in honeydews from both aphid species, while absent in oilseed rape nectar, nor being synthesized by O. bicornis. When bees were confined to a single honeydew type as the only carbohydrate source, consumption of M. persicae honeydew was confirmed for 47% of the bees and consumption of B. brassicae honeydew for only 3%. Increased mortality in the latter treatment provided further evidence that B. brassicae honeydew is an unsuitable food source for O. bicornis. All bees that were given the choice between honeydew and floral nectar showed significantly increased total sugar levels. However, the fact that no erlose was detected in these bees indicates that honeydew was not consumed when suitable floral nectar was available. This study demonstrates that honeydew exploitation by O. bicornis is dependent on honeydew type and the presence of floral nectar.

Based on the finding that Galanthus nivalis agglutinin (GNA) has direct negative effects on larvae of Chrysoperla carnea, laboratory experiments were conducted to investigate its toxicity to the adults. While the ingestion of GNA dissolved in an artificial diet did not affect adult longevity, there were concentration-dependent negative effects on the pre-oviposition period, daily fecundity and total fecundity (number of eggs laid). When GNA was ingested by larvae of C. carnea, it caused a significant extension of larval development time. Adults that had emerged from GNA-fed larvae did not differ from those that developed from control larvae in terms of adult fresh weight, pre-oviposition period and daily or total fecundity. However, fertility (proportion of hatching eggs) was significantly decreased in adults raised from GNA-treated larvae. Western blots revealed that GNA ingested by larvae of C. carnea was partly transferred to the adult stage and was subsequently excreted or digested within a few days. Our toxicity studies (Tier-1 tests) clearly established a hazard of GNA to adult C. carnea when administered to larvae or adults at high concentrations. Implications of these toxicity data for the non-target risk assessment of GNA-expressing transgenic crops are discussed.

Plants genetically modified to express Galanthus nivalis agglutinin (GNA) have been found to confer partial resistance to homopteran pests. Laboratory experiments were conducted to investigate direct effects of GNA on larvae of three species of aphid predators that differ in their feeding and digestive physiology, i.e. Chrysoperla carnea, Adalia bipunctata and Coccinella septempunctata. Longevity of all three predator species was directly affected by GNA, when they were fed a sucrose solution containing 1% GNA. However, a difference in sensitivity towards GNA was observed when comparing the first and last larval stage of the three species. In vitro studies revealed that gut enzymes from none of the three species were able to break down GNA. In vivo feed-chase studies demonstrated accumulation of GNA in the larvae. After the larvae had been transferred to a diet devoid of GNA, the protein stayed present in the body of C. carnea, but decreased over time in both ladybirds. Binding studies showed that GNA binds to glycoproteins that can be found in the guts of larvae of all three predator species. Immunoassay by Western blotting of haemolymph samples only occasionally showed the presence of GNA. Fluorescence microscopy confirmed GNA accumulation in the midgut of C. carnea larvae. Implications of these findings for non-target risk assessment of GNA-transgenic crops are discussed.

Earlier studies have shown that larvae of the green lacewing predator Chrysoperla carnea are negatively affected when preying on lepidopteran larvae that had been fed with transgenic maize expressing the cry1Ab gene from Bacillus thuringiensis. To test whether the observed effects were directly caused by the Cry1Ab toxin, we have developed a bioassay which allows us to feed high concentrations of the toxin directly to the predator. The results of these feeding studies show no direct toxic effect of Cry1Ab on C. carnea larvae. The amount of toxin ingested by first instar C. carnea in the present study was found to be a factor 10,000 higher than the concentration ingested when feeding on Bt-reared lepidopteran larvae, a treatment that was previously shown to have a negative impact on the predator. In addition, feeding first instar C. carnea with the Cry1Ab toxin did not affect the utilisation of subsequently provided prey. Furthermore, the quality of the prey provided to first instars did not affect the sensitivity of second and third instar C. carnea to the Bt-toxin. The presented results strongly suggest that C. carnea larvae are not sensitive to Cry1Ab and that earlier reported negative effects of Bt-maize were prey-quality mediated rather than direct toxic effects. These results, together with the fact that lepidopteran larvae are not regarded as an important prey for C. carnea in the field, led us to conclude that transgenic maize expressing Cry1Ab poses a negligible risk for this predator.

The development of a 16-item nutritional risk index (NRI) is chronicled from its inception through its application in three studies designed to assess its reliability and validity. Study I involved a survey of 401 community-dwelling elderly in St. Louis, Missouri who were interviewed at baseline, 4-5 mo later, and 1 yr later. Study II involved a cross-sectional survey of 377 male outpatients attending two clinics at the St. Louis Veterans Administration Medical Center. Study III involved a cross-sectional survey of 424 community-dwelling elderly in Houston, Texas. Internal consistency reliability coefficients ranged between 0.47 and 0.60, and test-retest reliability coefficients ranged between 0.65 and 0.71. Validity was established by using the NRI to predict the use of health services, as well as by correlating it with a variety of anthropometric, laboratory, and clinical markers of nutritional status. The utility of the NRI for future applications is discussed.

The purpose of this research was to evaluate two sources of error in the performance of computerized tomography (CT) and magnetic resonance imaging (MRI) of the abdomen/pelvis. The sources of error assessed were inter- and intra-observer reliability. Thirty abdomen/pelvis CT scans were randomly selected from each of three hospitals (university, VA, military) with different CT scanners. Two radiologists were recruited from each site to be CT observers. Forty-five abdomen/pelvis MRI scans were randomly selected from two institutions with different MRI scanners. Four observers were recruited to read the MRI scans. All scans were read blind without clinical information or patient identification. Overall inter-observer and intra-observer diagnostic agreement was significantly higher for MRI compared to CT. Inter-observer diagnostic agreement rates were also significantly higher for MRI when the etiologies of neoplastic vascular and metabolic/toxic were assigned. Observer experience in CT (range: 5-9 yr) or MRI (range: 2-4 yr) was not statistically associated with improved diagnostic agreement. This research addresses many of the criticisms of the MRI literature and compares MRI favorably to CT.