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We discuss options to reform the EU genetically modified organism (GMO) regulatory framework, make risk assessment and decision-making more consistent with scientific principles, and lay the groundwork for international coherence. In this third of three articles, we focus on labeling and coexistence as well as discuss the political reality and potential ways forward., Not duplicate with DiVA 1413755.Not duplicate with DiVA 1597019.QC 20200714. QC 20210923.

We discuss options to reform the EU genetically modified organisms (GMO) regulatory framework, make risk assessment and decision-making more consistent with scientific principles, and lay the groundwork for international coherence. The first in a three-part series, this article focuses on reform options related to the scope of the legislation and the GMO definition.

In January 2014, an international meeting sponsored by the International Life Sciences Institute/Health and Environmental Sciences Institute and the Canadian Food Inspection Agency titled “Genetic Basis of Unintended Effects in Modified Plants” was held in Ottawa, Canada, bringing together over 75 scientists from academia, government, and the agro-biotech industry. The objectives of the meeting were to explore current knowledge and identify areas requiring further study on unintended effects in plants and to discuss how this information can inform and improve genetically modified (GM) crop risk assessments. The meeting featured presentations on the molecular basis of plant genome variability in general, unintended changes at the molecular and phenotypic levels, and the development and use of hypothesis-driven evaluations of unintended effects in assessing conventional and GM crops. The development and role of emerging “omics” technologies in the assessment of unintended effects was also discussed. Several themes recurred in a number of talks; for example, a common observation was that no system for genetic modification, including conventional methods of plant breeding, is without unintended effects. Another common observation was that “unintended” does not necessarily mean “harmful”. This paper summarizes key points from the information presented at the meeting to provide readers with current viewpoints on these topics.

Several ant species are reported to be important predators of insect pests (Way and Khoo, 1992; Veeresh et al.. 1995). In East Africa, ants were found to be important natural enemies of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) (Van den Berg and Cock, 1993a, b), one of the most serious pests in the Old World (Reed and Pawar, 1982).

Der Beitrag fasst die Befunde einer Studie, im Rahmen des NFP59 durchgeführt, zur Haltung der Bevölkerung gegenüber der Grünen Gentechnik zusammen.

Several ant species are reported to be important predators of insect pests (Way and Khoo, 1992; Veeresh et al.. 1995). In East Africa, ants were found to be important natural enemies of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) (Van den Berg and Cock, 1993a, b), one of the most serious pests in the Old World (Reed and Pawar, 1982).

Seit der ersten kommerziellen Einführung einer Gentechpflanze im Jahre 1996 ist einiges passiert, sowohl in den Medien wie auch auf dem Feld. Mittlerweile werden gentechnisch veränderte Nutzpflanzen weltweit von 17,3 Mio. Bauern auf einer Fläche von 170 Mio. Hektaren angebaut. 90 % dieser Bauern sind Kleinbauern in Indien und anderen Entwicklungsländern, die insbesondere von der schädlingsresistenten Bt-Baumwolle profitieren. Wo immer der Schädlingsbefall ein Problem ist, kann die gentechnisch eingebaute Resistenz helfen den Spritzmitteleinsatz zu reduzieren und das Einkommen der Bauern zu erhöhen. Niemand würde jedoch behaupten, dass dies eine «goldene» Lösung für die zahlreichen Nachhaltigkeitsprobleme der Landwirtschaft sei. Die Risiken der Resistenzbildung bei Schädlingen, die mit einseitigen Anbaumethoden einhergehen, sind bereits bekannt aus dem Spritzmitteleinsatz in der konventionellen Landwirtschaft (die Schädlinge passen sich an). Dies ist ein Gesetz der Evolutionsbiologie und wer keine Vorsorge trifft muss mit den Konsequenzen leben.

Ever since the introduction of transgenic crops one of the main concerns has been their potential impact on non-target organisms. In this study we looked at the impact of transgenic disease-resistant wheat on different clones of the aphid Metopolophium dirhodum. Looking at different clones allowed us to assess whether impacts depended on aphid clone and whether there were aphid clone x wheat line interactions (genotype x environment interactions). The performance of 30 aphid clones on four different transgenic wheat lines and their corresponding control lines was studied in a life-table experiment assessing the following aphid life-history parameters: development time, adult weight, daily fecundity, total offspring number and the fitness estimate F'i. As expected, we found significant variation among aphid clones for all the measured life-history parameters. However,our experiments did not reveal any major impact of the transgenic wheat lines on aphid performance. The only significant difference was found for total offspring number which was reduced by 3.33% on the transgenic wheat lines compared with the control lines. There was no evidence for a genotype x environment interaction between aphid clones and wheat lines. In sum, our results imply that the genetically modified plants used in this assay were of similar host plant quality as the non-transformed control lines and that the introduced transgene had no major effect on the performance of individual aphid clones.

1 Insecticidal proteins can be excreted in the honeydew when sap-sucking insects feed on insect-resistant transgenic plants. Honeydew can be an important source of carbohydrates, thus potentially exposing a broad range of honeydew-feeding insects to transgene products. 2 Snowdrop lectin (Galanthus nivalis agglutinin; GNA) dissolved in a 2 m sucrose solution had no antifeedant effect on female aphid parasitoids (Aphidius ervi) but had a direct negative effect on their longevity. 3 When feeding on honeydew from Rhopalosiphum padi feeding on a GNA-containing artificial diet, Aphidius ervi suffered a longevity reduction that was more pronounced than was to be expected based on the detected GNA concentration in the honeydew. 4 Analysis of carbohydrate and amino acid composition revealed that a change in honeydew composition caused by a GNA-effect on the aphids could be a possible explanation for the additional reduction in parasitoid longevity. 5 When comparing the effect of honeydew from Sitobion avenae and R. padi feeding on GNA-expressing or nontransformed wheat plants on A. ervi longevity, aphid species was found to have a significant effect, whereas the wheat variety had no effect. The latter result was probably due to low GNA expression levels in the plants. Differences in nutritional suitability between honeydew from R. padi and S. avenae could be explained by differences in carbohydrate and amino acid composition. 6 This is the first study to demonstrate that GNA ingested by aphids and transported into the honeydew can negatively affect the parasitoids consuming this honeydew. 7 We recommend that honeydew should be considered as a route of exposure to transgene products in future risk assessment studies., 1 Insecticidal proteins can be excreted in the honeydew when sap-sucking insects feed on insect-resistant transgenic plants. Honeydew can be an important source of carbohydrates, thus potentially exposing a broad range of honeydew-feeding insects to transgene products. 2 Snowdrop lectin (Galanthus nivalis agglutinin; GNA) dissolved in a 2 m sucrose solution had no antifeedant effect on female aphid parasitoids (Aphidius ervi) but had a direct negative effect on their longevity. 3 When feeding on honeydew from Rhopalosiphum padi feeding on a GNA-containing artificial diet, Aphidius ervi suffered a longevity reduction that was more pronounced than was to be expected based on the detected GNA concentration in the honeydew. 4 Analysis of carbohydrate and amino acid composition revealed that a change in honeydew composition caused by a GNA-effect on the aphids could be a possible explanation for the additional reduction in parasitoid longevity. 5 When comparing the effect of honeydew from Sitobion avenae and R. padi feeding on GNA-expressing or nontransformed wheat plants on A. ervi longevity, aphid species was found to have a significant effect, whereas the wheat variety had no effect. The latter result was probably due to low GNA expression levels in the plants. Differences in nutritional suitability between honeydew from R. padi and S. avenae could be explained by differences in carbohydrate and amino acid composition. 6 This is the first study to demonstrate that GNA ingested by aphids and transported into the honeydew can negatively affect the parasitoids consuming this honeydew. 7 We recommend that honeydew should be considered as a route of exposure to transgene products in future risk assessment studies.

Among herbivorous insects with a complete metamorphosis the larval and adult stages usually differ considerably in their nutritional requirements and food ecology. Often, feeding on plant structural tissue is restricted to the larval stage, whereas the adult stage feeds primarily or exclusively on plant-provided food supplements such as nectar and pollen. Research on herbivore nutritional ecology has largely been divided along these lines. Most studies focus on actual herbivory by larval stages, while nectar and pollen feeding by adult herbivores has been addressed mainly in the light of plant-pollinator interactions. Only recently have we started to realize that the two phenomena are closely interlinked and that nectar and pollen feeding by adult herbivores can have a strong impact on plant-herbivore interactions. Here we address this largely ignored aspect of multitrophic level interactions and discuss its wide-ranging implications. Acronyms and Definitions Adult food fecundity index (AFFI): impact of adult feeding on fecundity expressed as mean fecundity realized by adults provided food divided by fecundity of unfed individuals Apparent competition: indirect interaction defined as a negative effect of one species on another species, mediated through action of shared natural enemies Dioecy: plant species with unisexual male and female flowers on separate plant individuals Monophagous: herbivores feeding on one plant species Multitrophic: involving several trophic levels, with plants, herbivores, and carnivores constituting the first three levels Oligophagous: herbivores feeding on several species within one family Optimal foraging theory: the theory that foraging behavior should maximize an animal's net rate of food or nutrient intake Optimal oviposition theory: the theory that an animal's oviposition behavior should maximize its reproductive fitness Parent-offspring conflict: conflict derived from conditions at which genetic interests of parents and offspring are, Among herbivorous insects with a complete metamorphosis the larval and adult stages usually differ considerably in their nutritional requirements and food ecology. Often, feeding on plant structural tissue is restricted to the larval stage, whereas the adult stage feeds primarily or exclusively on plant-provided food supplements such as nectar and pollen. Research on herbivore nutritional ecology has largely been divided along these lines. Most studies focus on actual herbivory by larval stages, while nectar and pollen feeding by adult herbivores has been addressed mainly in the light of plant-pollinator interactions. Only recently have we started to realize that the two phenomena are closely interlinked and that nectar and pollen feeding by adult herbivores can have a strong impact on plant-herbivore interactions. Here we address this largely ignored aspect of multitrophic level interactions and discuss its wide-ranging implications. Acronyms and Definitions Adult food fecundity index (AFFI): impact of adult feeding on fecundity expressed as mean fecundity realized by adults provided food divided by fecundity of unfed individuals Apparent competition: indirect interaction defined as a negative effect of one species on another species, mediated through action of shared natural enemies Dioecy: plant species with unisexual male and female flowers on separate plant individuals Monophagous: herbivores feeding on one plant species Multitrophic: involving several trophic levels, with plants, herbivores, and carnivores constituting the first three levels Oligophagous: herbivores feeding on several species within one family Optimal foraging theory: the theory that foraging behavior should maximize an animal's net rate of food or nutrient intake Optimal oviposition theory: the theory that an animal's oviposition behavior should maximize its reproductive fitness Parent-offspring conflict: conflict derived from conditions at which genetic interests of parents and offspring are

Feeding on sugar-rich foods such as nectar and honeydew is important for survival of many adult parasitoids. Especially in agricultural systems, honeydew is often the most prevalent carbohydrate source. However, relative to plant nectar, honeydew may be relatively unsuitable, as a result of an unfavourable sugar composition or the presence of secondary plant compounds. We studied survival of the aphid parasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae) on honeydew collected from various aphid species feeding on potato (Solanum tuberosum L., cv. Desiree) (Solanaceae), wheat (Triticum aestivum L., cv. Bobwhite) (Poaceae), or artificial diet, as well as the sugar composition of the different honeydews. Honeydews from the tested aphid species on potato, wheat, or artificial diet were found to be relatively suitable food sources for adult A. ervi, although not always as suitable as a 2 M sucrose solution. There were differences in honeydew sugar composition among the diffe! rent aphid species on the various host plants. Multivariate statistics showed that the factor 'aphid species' had a significant influence on the sugar composition of the honeydew, explaining 27% of the variation in the potato system and 89% in the wheat system. When exploring the relationship between carbohydrate composition of the honeydews from aphids on potato and wheat plants, and their nutritional value for A. ervi, data revealed that differences in parasitoid longevity can to some extent be explained by carbohydrate composition. Furthermore, our results confirm that sucrose and its hexose components glucose and fructose are very suitable carbohydrate sources for hymenopteran parasitoids and show that parasitoid survival on an equimolar solution of the two monosaccharides glucose and fructose does not exceed performance on the disaccharide sucrose., Feeding on sugar-rich foods such as nectar and honeydew is important for survival of many adult parasitoids. Especially in agricultural systems, honeydew is often the most prevalent carbohydrate source. However, relative to plant nectar, honeydew may be relatively unsuitable, as a result of an unfavourable sugar composition or the presence of secondary plant compounds. We studied survival of the aphid parasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae) on honeydew collected from various aphid species feeding on potato (Solanum tuberosum L., cv. Desiree) (Solanaceae), wheat (Triticum aestivum L., cv. Bobwhite) (Poaceae), or artificial diet, as well as the sugar composition of the different honeydews. Honeydews from the tested aphid species on potato, wheat, or artificial diet were found to be relatively suitable food sources for adult A. ervi, although not always as suitable as a 2 M sucrose solution. There were differences in honeydew sugar composition among the diffe! rent aphid species on the various host plants. Multivariate statistics showed that the factor 'aphid species' had a significant influence on the sugar composition of the honeydew, explaining 27% of the variation in the potato system and 89% in the wheat system. When exploring the relationship between carbohydrate composition of the honeydews from aphids on potato and wheat plants, and their nutritional value for A. ervi, data revealed that differences in parasitoid longevity can to some extent be explained by carbohydrate composition. Furthermore, our results confirm that sucrose and its hexose components glucose and fructose are very suitable carbohydrate sources for hymenopteran parasitoids and show that parasitoid survival on an equimolar solution of the two monosaccharides glucose and fructose does not exceed performance on the disaccharide sucrose.

During the adult stage many arthropod species, including aphid predators and parasitoids, depend on nectar and honeydew as a source of carbohydrates. Despite the importance of sugar feeding for these organisms, we know little about their energy and nutrient provision under field conditions. 2. Here we assessed the nutritional state of adult parasitoids, hoverflies and lacewings in a Swiss winter wheat (WW) and a spring wheat (SW) field and studied the contribution of honeydew to the diet of these aphidophagous insects. The total sugar level and the glucose-fructose ratio were used as indicators for nutritional state and sugar feeding. 3. Over 76% of the collected individuals from each of the three insect groups in both fields had recently consumed carbohydrates. The average nutritional state was significantly higher in the SW field for Chrysoperla carnea and Aphidius spp. 4. Honeydew consumption by insects is commonly investigated by analyzing target insects for the presence of honeydew ‘signature’ sugars, such as melezitose and erlose. However, our laboratory studies show that adults of the three insect orders investigated synthesize these ‘honeydew-specific’ sugars after sucrose feeding. 5. As the erlose-melezitose ratio of sucrose-fed Aphidius spp. and the hoverfly Episyrphus balteatus differed clearly from the honeydew sugar profiles of wheat infesting aphids, this ratio could be used as an alternative indicator of honeydew feeding. However, this method could not be used for the lacewing C. carnea. 6. Our data show that 55% (WW) and 59% (SW) of field-collected Aphidius spp. which showed evidence of sugar feeding could be classified as having consumed honeydew within the 24–48 h before collection. Evidence of honeydew feeding by hoverflies, on the other hand, was found to be much more variable, ranging from 0% in the WW field to 44% in the SW field. 7. This study shows that the detection of honeydew consumption in field-collected insects based on honeydew oligosa, During the adult stage many arthropod species, including aphid predators and parasitoids, depend on nectar and honeydew as a source of carbohydrates. Despite the importance of sugar feeding for these organisms, we know little about their energy and nutrient provision under field conditions. 2. Here we assessed the nutritional state of adult parasitoids, hoverflies and lacewings in a Swiss winter wheat (WW) and a spring wheat (SW) field and studied the contribution of honeydew to the diet of these aphidophagous insects. The total sugar level and the glucose-fructose ratio were used as indicators for nutritional state and sugar feeding. 3. Over 76% of the collected individuals from each of the three insect groups in both fields had recently consumed carbohydrates. The average nutritional state was significantly higher in the SW field for Chrysoperla carnea and Aphidius spp. 4. Honeydew consumption by insects is commonly investigated by analyzing target insects for the presence of honeydew ‘signature’ sugars, such as melezitose and erlose. However, our laboratory studies show that adults of the three insect orders investigated synthesize these ‘honeydew-specific’ sugars after sucrose feeding. 5. As the erlose-melezitose ratio of sucrose-fed Aphidius spp. and the hoverfly Episyrphus balteatus differed clearly from the honeydew sugar profiles of wheat infesting aphids, this ratio could be used as an alternative indicator of honeydew feeding. However, this method could not be used for the lacewing C. carnea. 6. Our data show that 55% (WW) and 59% (SW) of field-collected Aphidius spp. which showed evidence of sugar feeding could be classified as having consumed honeydew within the 24–48 h before collection. Evidence of honeydew feeding by hoverflies, on the other hand, was found to be much more variable, ranging from 0% in the WW field to 44% in the SW field. 7. This study shows that the detection of honeydew consumption in field-collected insects based on honeydew oligosa

The major pest problems in chickpea, i.e. pod borers (Helicoverpa armigera and H. punctigera), leafminer Liriomyza cicerina, black cutworm Agrotis ipsilon, aphids (Aphis craccivora), semilooper Autographa nigrisigna and bruchids (Callosobruchus spp.), and their management options (cultural, biological and chemical controls) are discussed. Low to moderate levels of resistance have been identified in the germplasm, and a few improved cultivars with resistance to pod borer and high grain yield have been developed. Germplasm accessions of the wild relatives of chickpea (Cicer bijugum, C. judaicum and C. reticulatum) can be used to increase the levels and diversify the bases of resistance to H. armigera. Efforts are also underway to utilize molecular techniques to increase the levels of resistance to pod borer. Synthetic insecticides, agronomic practices, nuclear polyhedrosis virus, entomopathogenic fungi, bacteria and natural plant products have been evaluated as components of pest management in chickpea.

Egg parasitoids of the genus Trichogramma are among the most important and best-studied natural enemies worldwide. Parasitism levels by Trichogramma vary greatly among different habitats, plants or plant structures on which the host eggs are located. Here we summarise the published evidence on mechanisms that may underlie the observed variation in parasitism rates. These mechanisms include plant spacing, plant structure, plant surface structure and chemistry, plant volatiles and plant colour. In addition, plants can affect parasitoid behaviour and activity by providing carbohydrate food sources such as nectar to the adult wasps, and by affecting the nutritional quality of the host eggs for progeny development. Knowledge of plant and habitat factors that affect Trichogramma spp. efficacy has important implications for biological control, and for assessing the risks that mass-released Trichogramma spp. may pose to non-target insects. [KEYWORDS: Biological control ; Conservation biological control ; Food ecology ; Multi-trophic interactions ; Non-target effects ; Plant volatiles ; Trichomes], Egg parasitoids of the genus Trichogramma are among the most important and best-studied natural enemies worldwide. Parasitism levels by Trichogramma vary greatly among different habitats, plants or plant structures on which the host eggs are located. Here we summarise the published evidence on mechanisms that may underlie the observed variation in parasitism rates. These mechanisms include plant spacing, plant structure, plant surface structure and chemistry, plant volatiles and plant colour. In addition, plants can affect parasitoid behaviour and activity by providing carbohydrate food sources such as nectar to the adult wasps, and by affecting the nutritional quality of the host eggs for progeny development. Knowledge of plant and habitat factors that affect Trichogramma spp. efficacy has important implications for biological control, and for assessing the risks that mass-released Trichogramma spp. may pose to non-target insects. [KEYWORDS: Biological control ; Conservation biological control ; Food ecology ; Multi-trophic interactions ; Non-target effects ; Plant volatiles ; Trichomes]

Honeydew is a common sugar-rich excretion of aphids and other phloem-feeding insects and represents the primary sugar in many agricultural systems. When honeydew-producing insects feed on genetically modified plants, the honeydew can contain amounts of the transgene product. Here we address whether this route of exposure poses a risk for non-target insects. Three species of parasitic wasps were selected: i.e. Aphidius colemani, Trichogramma brassicae and Cotesia glomerata, all of which are known to use honeydew as a carbohydrate source in the field. Wasps were fed sucrose solutions with varying concentrations of snowdrop lectin (Galanthus nivalis agglutinin, GNA), a protein that has been engineered into crops to confer resistance against homopteran pests and that has been detected in honeydew. Parameters evaluated included gustatory response, longevity, fecundity, progeny emergence and sex ratio. While A. colemani and T. brassicae, but not C. glomerata, were able to detect GNA, this gustatory recognition had no effect on the acceptance of a GNA-sucrose solution. In all three species, GNA ingestion reduced parasitoid survival significantly. However, in respect to fecundity, negative effects were observed for T. brassicae but not for A. colemani. The results suggest that the effect of GNA consumption may depend on the specifics of a parasitoid's biology, especially its longevity and its mode of egg maturation. [KEYWORDS: GNA - Honeydew - Parasitoids - Risk-assessment - Transgenic plants], Honeydew is a common sugar-rich excretion of aphids and other phloem-feeding insects and represents the primary sugar in many agricultural systems. When honeydew-producing insects feed on genetically modified plants, the honeydew can contain amounts of the transgene product. Here we address whether this route of exposure poses a risk for non-target insects. Three species of parasitic wasps were selected: i.e. Aphidius colemani, Trichogramma brassicae and Cotesia glomerata, all of which are known to use honeydew as a carbohydrate source in the field. Wasps were fed sucrose solutions with varying concentrations of snowdrop lectin (Galanthus nivalis agglutinin, GNA), a protein that has been engineered into crops to confer resistance against homopteran pests and that has been detected in honeydew. Parameters evaluated included gustatory response, longevity, fecundity, progeny emergence and sex ratio. While A. colemani and T. brassicae, but not C. glomerata, were able to detect GNA, this gustatory recognition had no effect on the acceptance of a GNA-sucrose solution. In all three species, GNA ingestion reduced parasitoid survival significantly. However, in respect to fecundity, negative effects were observed for T. brassicae but not for A. colemani. The results suggest that the effect of GNA consumption may depend on the specifics of a parasitoid's biology, especially its longevity and its mode of egg maturation. [KEYWORDS: GNA - Honeydew - Parasitoids - Risk-assessment - Transgenic plants]

Many adult Lepidoptera are dependent on carbohydrate-rich solutions such as nectar and honeydew. These food sources can contain a range of carbohydrates as well as low levels of other compounds, including free amino acids, proteins and lipids. Little is known about the nutritional value of individual nectar sugars and amino acids for adult Lepidoptera. Ten sugars occurring in nectar and honeydew were tested with respect to their effects on a number of Pieris brassicae life-table parameters. In similar experiments it was investigated whether the butterfly derives nutritional benefits from mixtures of common non-essential or essential amino acids when provided either in water or in a sucrose solution. Food sources were found to have a significant effect on butterfly fertility, longevity, lifetime fecundity and daily oviposition rate. Whereas a number of sugars significantly increase longevity, melibiose and melezitose reduce P. brassicae longevity. Butterfly fecundity is compromized significantly by sucrose and melibiose. Glucose is the only sugar that has a positive effect on both longevity and fecundity as well as a number of oviposition parameters. Amino acids seem to have no or only a minor effect on the life-table parameters tested. However, when provided in sucrose, they appear to compensate for the negative effect of pure sucrose on fecundity. A comparison with an earlier study on the gustatory response of P. brassicae shows that there is only a weak correlation between the nutritional value of sugars and amino acid mixtures and their perceptibility. [KEYWORDS: cabbage white butterfly, fecundity, honeydew, Lepidoptera, longevity, nectar, oviposition, sugar utilization], Many adult Lepidoptera are dependent on carbohydrate-rich solutions such as nectar and honeydew. These food sources can contain a range of carbohydrates as well as low levels of other compounds, including free amino acids, proteins and lipids. Little is known about the nutritional value of individual nectar sugars and amino acids for adult Lepidoptera. Ten sugars occurring in nectar and honeydew were tested with respect to their effects on a number of Pieris brassicae life-table parameters. In similar experiments it was investigated whether the butterfly derives nutritional benefits from mixtures of common non-essential or essential amino acids when provided either in water or in a sucrose solution. Food sources were found to have a significant effect on butterfly fertility, longevity, lifetime fecundity and daily oviposition rate. Whereas a number of sugars significantly increase longevity, melibiose and melezitose reduce P. brassicae longevity. Butterfly fecundity is compromized significantly by sucrose and melibiose. Glucose is the only sugar that has a positive effect on both longevity and fecundity as well as a number of oviposition parameters. Amino acids seem to have no or only a minor effect on the life-table parameters tested. However, when provided in sucrose, they appear to compensate for the negative effect of pure sucrose on fecundity. A comparison with an earlier study on the gustatory response of P. brassicae shows that there is only a weak correlation between the nutritional value of sugars and amino acid mixtures and their perceptibility. [KEYWORDS: cabbage white butterfly, fecundity, honeydew, Lepidoptera, longevity, nectar, oviposition, sugar utilization]

Most Lepidoptera feed during the adult stage on carbohydrate- rich food sources, primarily floral nectar. However, little is known about the factors leading to the acceptance of a possible food source. It is reported that butterflies select for nectar rich in sucrose and amino acids. This suggests that the insects have developed a sensitivity to these nectar compounds. We tested females of the large cabbage white, Pieris brassicae L. (Lepidoptera: Pieridae) for their responses to 10 different nectar- or honeydew-sugars after either tarsal or proboscis stimulation. In no-choice experiments, food-deprived P. brassicae showed the strongest response to sucrose, followed by fructose. Other sugars, including galactose, glucose, maltose, mannose, melezitose, melibiose, raffinose and trehalose, did not elicit a feeding response. Mixtures of essential or common non-essential amino acids did not stimulate feeding. In a choice situation, P. brassicae preferred sucrose over fructose, whereas they accepted a sucrose and amino acid solution equally to a plain sucrose solution. The results indicate that for P. brassicae, feeding is mainly elicited by sucrose and fructose. [KEYWORDS: amino acids; cabbage white; nectar; Pieris brassicae; sugars Heliothis-virescens; honey-bees; adult diet; nectar; lepidoptera; noctuidae; sugars; preferences; papilionidae; biology]