Statistical method for testing the neutral mutation hypothesis by DNA polymorphism.

KEGG(Kyoto Encyclopedia of Genes and Genomes)〔和文〕 (特集 ゲノム医学の現在と未来--基礎と臨床) -- (データベース)

Traditionally, measurement of the acute toxicity of pesticides to beneficial arthropods has relied largely on the determination of an acute median lethal dose or concentration. However, the estimated lethal dose during acute toxicity tests may only be a partial measure of the deleterious effects. In addition to direct mortality induced by pesticides, their sublethal effects on arthropod physiology and behavior must be considered for a complete analysis of their impact. An increasing number of studies and methods related to the identification and characterization of these effects have been published in the past 15 years. Review of sublethal effects reported in published literature, taking into account recent data, has revealed new insights into the sublethal effects of pesticides including effects on learning performance, behavior, and neurophysiology. We characterize the different types of sublethal effects on beneficial arthropods, focusing mainly on honey bees and natural enemies, and we describe the methods used in these studies. Finally, we discuss the potential for developing experimental approaches that take into account these sublethal effects in integrated pest management and the possibility of integrating their evaluation in pesticide registration procedures.

The Sublethal Effects of Pesticides on Beneficial Arthropods

Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S. A. S. Nagar,Mohali, Punjab-160 062, India, Institute of Biochemistry, Faculty of Medicine, Polytechnic University, Via Ranieri 67, IT-60100 Ancona, Italy,Green Biotechnology Research Group, The Special Division for Human Life Technology, National Institute of Advanced Industrial Science andTechnology, 1-8-31 Midorigaoka, Ikeda, Osaka-563-8577, Japan, and Department of Medicinal Chemistry & Natural Products,The Hebrew University of Jerusalem, School of Pharmacy-Faculty of Medicine, Jerusalem 91120, IsraelReceived March 2, 2004

Chitosan chemistry and pharmaceutical perspectives.

Bees are subject to numerous pressures in the modern world. The abundance and diversity of flowers has declined, bees are chronically exposed to cocktails of agrochemicals, and they are simultaneously exposed to novel parasites accidentally spread by humans. Climate change is likely to exacerbate these problems in the future. Stressors do not act in isolation; for example pesticide exposure can impair both detoxification mechanisms and immune responses, rendering bees more susceptible to parasites. It seems certain that chronic exposure to multiple, interacting stressors is driving honey bee colony losses and declines of wild pollinators, but such interactions are not addressed by current regulatory procedures and studying these interactions experimentally poses a major challenge. In the meantime, taking steps to reduce stress on bees would seem prudent; incorporating flower-rich habitat into farmland, reducing pesticide use through adopting more sustainable farming methods, and enforcing effective quarantine measures on bee movements are all practical measures that should be adopted. Effective monitoring of wild pollinator populations is urgently needed to inform management strategies into the future.

https://science.sciencemag.org/content/sci/early/2015/02/25/science.1255957.full.pdf

Bee declines driven by combined stress from parasites, pesticides, and lack of flowers

Potency and ultrastructural effects of tebufenozide in Spodoptera exigua

The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a persistent agricultural pest in many areas of the world, and it successfully invaded China in 2019. Like many lepidopteran insects, S. frugiperda pupates live in soil for protection under harsh environmental conditions. We conducted a serial experiment to understand the pupation behavior of S. frugiperda, as well as the effect of soil moisture on pupation. A digital video camera system was used to monitor larval pupation behavior of S. frugiperda. Four different soil moisture choices (5, 25, 50, and 80%) were used to determine the pupation location and behavior of S. frugiperda under laboratory conditions. The four-choice tests showed that most of the larvae prefer to pupate at 25–50% in saturated soil, and other few larvae burrow and pupate under dry (5%) or wet (80%) soils. In the no-choice tests, S. frugiperda larvae did not prefer the wet soil (80%) to pupate. However, soil moisture did not significantly affect the emergence rates. This study helps to increase the knowledge on pupation ecology of S. frugiperda and implies management strategies for this destructive pest.

Effect of soil moisture on pupation behavior and inhabitation of Spodoptera frugiperda (Lepidoptera: Noctuidae)

GOBBI, A.; BUDIA, F.; SMAGGHE, G.; VINUELA, E., 1998: Effects of tebufenozide on Spodoptera littoralis (Boisduval) larvae. Influence of different application techniques.Bol. San. Veg. Plagas, 24(1): 41-56.Effects of tebufenozide (3,5-acidodimetilbenzoico 1-(1,1 dimetiletil)-2-(4-etilben-zoil) hidracida), on neonate and L 4 larvae of Spodoptera littoralis (Boisduval) havebeen evaluated in laboratory with different application techniques: residual contact, to-pical application and ingestion via treated diet. The range of concentrations studied va-ried between 0.001 and 10,000 mg a.i./kg. diet in ingestion studies and between 0.1 and1,000 mg a.i./l in topical and residual contact ones. Tebufenozide was very effective byingestion in the two larval instars and a 100% mortality was scored from 1 mg a.i./kg.diet onwards. Up to 0.1 mg a.i../kg. diet, insects reached the pupal stage, but a sig-nificant percentage of adults exhibited some malformations. Tebufenozide also had aslight residual contact action and a minor topical action on L

Acción del tebufenocida sobre larvas de Spodoptera littoralis (boisduval): Influencia de la forma de aplicación

Flower inhabiting thrips (Order: Thysanoptera) are a major threat to fruit quality in strawberry production around the world. As chemical control is often inefficient, alternative control measures are of broad and current interest. Their fast reproduction makes predatory mites highly suitable for thrips control in a crop with a relatively short cropping season like strawberry. However, climatic conditions of strawberry production can differ strongly depending on the production system (glasshouse, plastic tunnel, open field, etc.) and the time span of cultivation (depending mostly on planting date and the type of cultivar: summer-or everbearing). As predatory mites typically display a temperature-dependent life history and the current commercially available thrips predating phytoseids vary in geographic origin, one can assume that under certain climatic conditions some species will be more applicable than others. The goal of this study is to determine which species are suitable for which climatic conditions. Therefore all (Belgian) production systems and time spans are categorized into three climate types, simulated in the laboratory. The population build-up of seven predatory mite species (A. degenerans, A. montdorensis, A. andersoni, A. limonicus, A. swirskii, N. cucumeris and E. gallicus) were assessed for each of these climatic conditions. Under the coldest condition (A), the in West-Europe indigenous E. gallicus was the only species with a significant population build up. When moderate conditions (B) were simulated E. gallicus, N. cucumeris and A. limonicus were most successful. The warmest regime (C) was most adequate for E. gallicus and A. swirskii.

/pdf/matching-commercial-thrips-predating-phytoseids-with-the-xbjyypwb6z.pdf

Matching commercial thrips predating phytoseids with the highly diversified climatic conditions of different strawberry production systems.

RH-0345 (halofenozide), a bisacylhydrazine derivative, is a nonsteroidal ecdysteroid agonist that mimics the action of the moulting hormones, while KK-42, an imidazole compound, is a potent inhibitor of ecdysteroid biosynthesis. Recent experiments with Tenebrio molitor suggested that the reduction of ecdysteroid titer, leading to a reduction of reproductive capacity, is due to a direct and rapid action of KK-42 on ecdysterold biosynthesis. Moreover, RH-0345 could partly restore the effects on reproductive events induced by KK-42. On the other hand, RH-0345 was found to affect growth and development of ovaries in a manner similar to that 20-hydroxyecdysone (20-E) and increased the ecdysteroid production. Therefore, the present study evaluates KK-42 applied topically (10 microg/insect) in combination with RH-0345 or 20-E in order to obtain more information on the mode of action of this compound on reproduction in T. molitor. In a first series of experiments, the compounds were assayed on morphometric measurements of freshly laid eggs. Results showed that both the weight and the volume of eggs increase significantly in series treated by KK-42 followed by 20-hydroxyecdysone as compared to controls and treated series by KK-42 followed by RH-0345. Data from enzyme immunoassay measurements revealed that KK-42 applied before 20-E was found to reduce significantly the amounts of free ecdysteroids in eggs comparatively to the others series.

Guy Smagghe

Papers

Potency and ultrastructural effects of tebufenozide in Spodoptera exigua

Effect of soil moisture on pupation behavior and inhabitation of Spodoptera frugiperda (Lepidoptera: Noctuidae)

Acción del tebufenocida sobre larvas de Spodoptera littoralis (boisduval): Influencia de la forma de aplicación

Matching commercial thrips predating phytoseids with the highly diversified climatic conditions of different strawberry production systems.

Activity of kk-42 in combinated treatment with RH-0345 or 20-hydroxyecdysone on morphometric measurements and free ecdysteroid in eggs of mealworms.