Mating Frequency of European Corn Borer (Lepidoptera: Crambidae) in Minnesota, Kansas, and Texas

The frequency of mating and polyandry in natural populations are important parameters for understanding evolutionary dynamics. Mating frequency among natural populations of Ostrinia nubilalis (Hübner) [Lepidoptera: Crambidae] are quite variable. Showers et al. (1974) found 91.1, 73.8, and 71.3% of females had mated during the second flight over 1971-3 at one location in Iowa. During 1971, only 10% mated multiple times, with lower levels of polyandry in subsequent years. In an earlier study in Iowa, Pesho (1961) found that 65-100 % of females had mated and up to 43% had mated more than once. A population in southwestern Ontario averaged 73% mating and 37% polyandry for the 5-year period from 1971-5, a higher rate of polyandry than during the same period in Iowa (Elliot, 1977). In this note, we amplify these previously published results by reporting the mating status of female O. nubilalis captured in light traps in Minnesota, Kansas and Texas. We also provide evidence that some females in natural populations may be sperm-limited

Frequency of Resistance to Bacillus thuringiensis Toxin Cry1Ab in an Iowa Population of European Corn Borer (Lepidoptera: Crambidae)

The refuge plus high-dose strategy for resistance management assumes that the frequency of resistance alleles is low. We used an F2 screen to estimate the frequency of resistance to transgenic corn that produces Bacillus thuringiensis Berliner Cry1Ab toxin (Bt corn) in an Iowa population of European corn borer, Ostrinia nubilalis (Hu¨ bner). We also proposed a modiÞcation to the statistical analysis of the F2 screen that extends its application for nonuniform prior distributions and for repeated sampling of a single population. Based on a sample of 188 isofemale lines derived from females caught at light traps during the 2nd ßight of 1997, we show with 95% conÞdence that the frequency of resistance to Bt corn was ,3.9 3 1023 in this Iowa population. These results provide weak evidence that the refuge plus high-dose strategy may be effective for managing resistance in O. nubilalis to Bt corn. Partial resistance to Cry1Ab toxin was found commonly. The 95% CI for the frequency of partial resistance were [8.231024, 9.431023] for the Iowa population. Variable costs of the method were $14.90 per isofemale line, which was a reduction of 25% compared with our initial estimate

Why compatibilist intuitions are not mistaken: a reply to Feltz and Millan

In the past decade, a number of empirical researchers have suggested that laypeople have compatibilist intuitions. In a recent paper, Feltz and Millan (2015) have challenged this conclusion by claiming that most laypeople are only compatibilists in appearance and are in fact willing to attribute free will to people no matter what. As evidence for this claim, they have shown that an important proportion of laypeople still attribute free will to agents in fatalistic universes. In this paper, we first argue that Feltz and Millan’s error-theory rests on a conceptual confusion: it is perfectly acceptable for a certain brand of compatibilist to judge free will and fatalism to be compatible, as long as fatalism does not prevent agents from being the source of their actions. We then present the results of two studies showing that laypeople’s intuitions are best understood as following a certain brand of source compatibilism rather than a “free-will-no-matter-what” strategy

Genetically engineered organisms and the environment: Current status and recommendations

The Ecological Society of America has evaluated the ecological effects of current and potential uses of field-released genetically engineered organisms (GEOs), as described in this Position Paper. Some GEOs could play a positive role in sustainable agriculture, forestry, aquaculture, bioremediation, and environmental management, both in developed and developing countries. However, deliberate or inadvertent releases of GEOs into the environment could have negative ecological effects under certain circumstances. Possible risks of GEOs could include: (1) creating new or more vigorous pests and pathogens; (2) exacerbating the effects of existing pests through hybridization with related transgenic organisms; (3) harm to nontarget species, such as soil organisms, non-pest insects, birds, and other animals; (4) disruption of biotic communities, including agroecosystems; and (5) irreparable loss or changes in species diversity or genetic diversity within species. Many potential applications of genetic engineering extend beyond traditional breeding, encompassing viruses, bacteria, algae, fungi, grasses, trees, insects, fish, and shellfish. GEOs that present novel traits will need special scrutiny with regard to their environmental effects. The Ecological Society of America supports the following recommendations. (1) GEOs should be designed to reduce environmental risks. (2) More extensive studies of the environmental benefits and risks associated with GEOs are needed. (3) These effects should be evaluated relative to appropriate baseline scenarios. (4) Environmental release of GEOs should be prevented if scientific knowledge about possible risks is clearly inadequate. (5) In some cases, post-release monitoring will be needed to identify, manage, and mitigate environmental risks. (6) Science-based regulation should subject all transgenic organisms to a similar risk assessment framework and should incorporate a cautious approach, recognizing that many environmental effects are GEO- and site-specific. (7) Ecologists, agricultural scientists, molecular biologists, and others need broader training and wider collaboration to address these recommendations. In summary, GEOs should be evaluated and used within the context of a scientifically based regulatory policy that encourages innovation without compromising sound environmental management. The Ecological Society of America is committed to providing scientific expertise for evaluating and predicting the ecological effects of field-released transgenic organisms

Environmental risk assessment of genetically modified plants - concepts and controversies

Background and purpose: In Europe, the EU Directive 2001/18/EC lays out the main provisions of environmental risk assessment (ERA) of genetically modified (GM) organisms that are interpreted very differently by different stakeholders. The purpose of this paper is to: (a) describe the current implementation of ERA of GM plants in the EU and its scientific shortcomings, (b) present an improved ERA concept through the integration of a previously developed selection procedure for identification of non-target testing organisms into the ERA framework as laid out in the EU Directive 2001/18/EC and its supplement material (Commission Decision 2002/623/EC), (c) describe the activities to be carried out in each component of the ERA and (d) propose a hierarchical testing scheme. Lastly, we illustrate the outcomes for three different crop case examples. Main features: Implementation of the current ERA concept of GM crops in the EU is based on an interpretation of the EU regulations that focuses almost exclusively on the isolated bacteria-produced novel proteins with little consideration of the whole plant. Therefore, testing procedures for the effect assessment of GM plants on non-target organisms largely follow the ecotoxicological testing strategy developed for pesticides. This presumes that any potential adverse effect of the whole GM plant and the plant-produced novel compound can be extrapolated from testing of the isolated bacteriaproduced novel compound or can be detected in agronomic field trials. This has led to persisting scientific criticism. Results: Based on the EU ERA framework, we present an improved ERA concept that is system oriented with the GM plant at the centre and integrates a procedure for selection of testing organisms that do occur in the receiving environment. We also propose a hierarchical testing scheme from laboratory studies to field trials and we illustrate the outcomes for three different crop case examples. Conclusions and recommendations: Our proposed concept can alleviate a number of deficits identified in the current approach to ERA of GM plants. It allows the ERA to be tailored to the GM plant case and the receiving environment

Mating Frequency of European Corn Borer (Lepidoptera: Crambidae) in Minnesota, Kansas, and Texas

The frequency of mating and polyandry in natural populations are important parameters for understanding evolutionary dynamics. Mating frequency among natural populations of Ostrinia nubilalis (Hübner) [Lepidoptera: Crambidae] are quite variable. Showers et al. (1974) found 91.1, 73.8, and 71.3% of females had mated during the second flight over 1971-3 at one location in Iowa. During 1971, only 10% mated multiple times, with lower levels of polyandry in subsequent years. In an earlier study in Iowa, Pesho (1961) found that 65-100 % of females had mated and up to 43% had mated more than once. A population in southwestern Ontario averaged 73% mating and 37% polyandry for the 5-year period from 1971-5, a higher rate of polyandry than during the same period in Iowa (Elliot, 1977). In this note, we amplify these previously published results by reporting the mating status of female O. nubilalis captured in light traps in Minnesota, Kansas and Texas. We also provide evidence that some females in natural populations may be sperm-limited

Transgenic insecticidal crops and natural enemies: A detailed review of laboratory studies

This review uses a data-driven, quantitative method to summarize the published, peer-reviewed literature about the impact of genetically modified (GM) plants on arthropod natural enemies in laboratory experiments. The method is similar to meta-analysis, and, in contrast to a simple author-vote counting method used by several earlier reviews, gives an objective, data-driven summary of existing knowledge about these effects. Significantly more non-neutral responses were observed than expected at random in 75% of the comparisons of natural enemy groups and response classes. These observations indicate that Cry toxins and proteinase inhibitors often have non-neutral effects on natural enemies. This synthesis identifies a continued bias toward studies on a few predator species, especially the green lacewing, Chrysoperla cornea Stephens, which may be more sensitive to GM insecticidal plants (16.8% of the quantified parameter responses were significantly negative) than predators in general (10.9% significantly negative effects without C. cornea). Parasitoids were more susceptible than predators to the effects of both Cry toxins and proteinase inhibitors, with fewer positive effects (18.0%, significant and nonsignificant positive effects combined) than negative ones (66.1%, significant and nonsignificant negative effects combined). GM plants can have a positive effect on natural enemies (4.8% of responses were significantly positive), although significant negative (21.2%) effects were more common. Although there are data on 48 natural enemy species, the database is still far from adequate to predict the effect of a Bt toxin or proteinase inhibitor on natural enemies

Efeito de espécies vegetais em bordadura em cebola sobre a densidade populacional de tripes e sirfídeos predadores.

Analisou-se a relação entre o efeito do plantio de diferentes espécies vegetais, em bordadura, na cultura da cebola, Allium cepa L, na incidência de Thrips tabaci Lind. e sirfídeos predadores, Toxomerus spp. O experimento foi conduzido na Epagri, EE de Ituporanga, de agosto a dezembro de 1998. Os tratamentos foram cebola em monocultivo; cebola + trigo mourisco (Fagopyrum esculentum Moench); cebola + nabo forrageiro (Raphanus sativus L. var. oleiferus Metzg.); cebola + cenoura (Daucus carota L., cv. Nantes e cv. Brasília); cebola + milho (Zea mays L.); cebola + rúcula (Eruca sativa L.) + vegetação espontânea. O plantio de diferentes espécies vegetais em bordadura não provocou diferenças significativas na incidência de tripes e sirfídeos predadores. A produtividade comercial de bulbos de cebola foi similar em sistema de monocultivo e diversificado, sugerindo ser possível adotar tais sistemas sem perdas em rendimento