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Tomato treatment with chemical inducers reduces the performance of Spodoptera littoralis (Lepidoptera: Noctuidae)
No full textThis article is not available on ChesterRep.The evolving understanding of plant signaling pathways has promoted the possibility of using chemical inducers as an effective tactic for crop protection. In this study, under greenhouse conditions, we conducted a growth assay of Spodoptera littoralis (Boisduval) larvae on tomato plants treated with BTH (S-methyl benzo [1, 2, 3] thiadiazole 7 carbothioate) as a salicylic acid mimic, PDJ (propyl [1RS, 2RS]-[3-oxo-2-pentylcyclopentyl] acetate) as a jasmonic acid-mimic or both chemicals as a combined treatment. The larval body weight of S. littoralis was drastically reduced with each chemical compared to control plants, and there was a significant synergistic interaction. Overall, the total weight gain of surviving larvae fed on treated plants was distinctly tenfold less than for those fed on control plants. Moreover, incorporating the chemical inducers in artificial diets had no direct or toxic impact on the larval body weight of S. littoralis under laboratory conditions. Larval survival rates were significantly lower (35–40 %) on treated plants with either combined or independent inducers’ treatments compared with control plants after 15-day feeding. In contrast, incorporating the chemical inducers in artificial diets had no direct effect on larval survival rates under laboratory conditions. The applied concentrations of BTH and PDJ had no detectable phytotoxicity to tomato plants. Our results demonstrate that BTH and PDJ can act synergistically when applied to tomato to reduce the performance of S. littoralis. These findings stress that the application of chemical inducers could provide an environment-friendly tactic to help manage insect pests and thereby play multiple roles in improving the overall plant resistance to herbivore pests.Unfunde
The prospect of applying chemical elicitors and plant strengtheners to enhance the biological control of crop pests
No full textAn imminent food crisis reinforces the need for novel strategies to increase crop yields worldwide. Effective control of pest insects should be part of such strategies, preferentially with reduced negative impact on the environment and optimal protection and utilization of existing biodiversity. Enhancing the presence and efficacy of native biological control agents could be one such strategy. Plant strengthener is a generic term for several commercially available compounds or mixtures of compounds that can be applied to cultivated plants in order to 'boost their vigour, resilience and performance'. Studies into the consequences of boosting plant resistance against pests and diseases on plant volatiles have found a surprising and dramatic increase in the plants' attractiveness to parasitic wasps. Here, we summarize the results from these studies and present new results from assays that illustrate the great potential of two commercially available resistance elicitors. We argue that plant strengtheners may currently be the best option to enhance the attractiveness of cultivated plants to biological control agents. Other options, such as the genetic manipulation of the release of specific volatiles may offer future solutions, but in most systems, we still miss fundamental knowledge on which key attractants should be targeted for this approach.European Science Foundation; Swiss National Science FoundationAAM supplied by author and uploaded to ChesterRep 07/11/202
Plant strengtheners enhance parasitoid attraction to herbivore‐damaged cotton via qualitative and quantitative changes in induced volatiles
No full textThis is the peer reviewed version of the following article: [Sobhy, I. S., Erb, M., & Turlings, T. C. J. (2015). Plant strengtheners enhance parasitoid attraction to herbivore‐damaged cotton via qualitative and quantitative changes in induced volatiles. Pest Management Science, 71(5), 686-693], which has been published in final form at [https://doi.org/10.1002/ps.3821]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.BACKGROUND: Herbivore-damaged plants release a blend of volatile organic compounds (VOCs) that differs from undamaged plants. These induced changes are known to attract the natural enemies of the herbivores and therefore are expected to be important determinants of the effectiveness of biological control in agriculture. One way of boosting this phenomenon is the application of plant strengtheners, which has been shown to enhance parasitoid attraction in maize. It is unclear whether this is also the case for other important crops.
RESULTS: The plant strengtheners BTH [benzo (1,2,3) thiadiazole-7-carbothioic acid S-methyl ester] and laminarin were applied to cotton plants, and the effects on volatile releases and the attraction of three hymenopteran parasitoids, Cotesia marginiventris, Campoletis sonorensis and Microplitis rufiventris, were studied. After treated and untreated plants were induced by real or simulated caterpillar feeding, it was found that BTH treatment increased the attraction of the parasitoids, whereas laminarin had no significant effect. BTH treatment selectively increased the release of two homoterpenes and reduced the emission of indole, the latter of which had been shown to interfere with parasitoid attraction in earlier studies. Canonical variate analyses of the data show that the parasitoid responses were dependent on the quality rather than the quantity of volatile emission in this tritrophic interaction.
CONCLUSION: Overall, these results strengthen the emerging paradigm that induction of plant defences with chemical elicitors such as BTH could provide a sustainable and environmentally friendly strategy for biological control of pests by enhancing the attractiveness of cultivated plants to natural enemies of insect herbivores.UnfundedAAM supplied by author and uploaded to ChesterRep 07/11/202
Life history traits of Blaptostethus pallescens (Hemiptera: Anthocoridae), a candidate for use in augmentative biological control in Egypt
No full textThis article is not available on ChesterRep.Blaptostethus pallescens Poppius (Hemiptera: Anthocoridae) is an abundant native predator in mango orchards and other cropping systems in Egypt. To determine suitable mass-rearing conditions for this little-studied species, we assessed some of its biological characteristics. Testing its thermal response at three constant temperatures (20, 25, 30 °C), showed that immature development time and adult longevity decreased with increasing temperature. Reproductive success of individual females was greatest when reared at 25 °C (84.3 ± 3.1 eggs) rather than at 20 °C (46.6 ± 2.0 eggs) or 30 °C (65.2 ± 2.5 eggs). Although B. pallescens reared at 25 °C had a significantly higher net reproductive rate (R0), which may be attributed to their relatively rapid development and high fecundity, we argue that 30 °C seems to be more convenient for rearing B. pallescens, as mean generation time (T) and doubling time (DT) are clearly shorter, thus more individuals could be reared per unit of time at 30 °C. Mating significantly reduced male and female longevity, as unmated adults lived 25–45 % longer than mated individuals did. Unmated females did not lay eggs, suggesting that mating is a prerequisite for egg maturation. Adult males and females performed best, in terms of longevity, when fed Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs instead of non-prey diets. However, diets of plant sap or pollen could sustain adults in times of limited egg availability. Because its biology is similar to that of other subtropical anthocorids already reared for augmentative releases, B. pallescens may be amenable to mass-rearing using already established techniques. Therefore, B. pallescens could be used to improve augmentative biological control in crops such as mango or maize in Egypt where it already naturally occurs, and therefore would not engender concerns over non-target effects that an exotic, generalist biological control agent would.Public Service Centre for Biological Control (PSCBC), Faculty of Agriculture, Suez Canal University, Ismailia, Egyp
Physical exercise impacts the performance of explosives detection dogs
No full textDogs (Canis familiaris) are widely used as scent detectors due to their sensitive olfactory capabilities, endurance, and ability to cover large areas quickly. They are in high demand due to a global rise in terrorist threats using specialized explosive contraptions. Detection dogs are often faced with high temperatures and physical exertion, which can increase panting rate as a function of evaporative cooling, inhibiting olfactory ability. This study examined the impact of exercise on the search performance of 11 explosive detection dogs (eight labradors and three springer spaniels). They completed two trial sets: one after exercise with a ball thrower and one without exercise. They were timed while searching for three types of explosives: trinitrotoluene, composition-4, and ammonium nitrate. Data were analyzed in R using mixed effects models, revealing that exercise significantly affected search duration and success for all types of explosives. Searches averaged 29.58 seconds without exercise, while post-exercise searches took 44.91 seconds. Dogs were 1.14 times more likely to locate explosives without prior exercise. Dogs took the longest to find trinitrotoluene and were fastest with ammonium nitrate and composition-4. These findings highlight the importance of allowing detection dogs adequate rest, as even brief exercise can impact their search performance.N/
Palgrave Studies in Comics and Graphic Novels
No full textThe original version of this chapter has been revised and an updated bibliography has been incorporated in the chapter.Unfunde
Early Years Science Education: A Contemporary Look
Get PDFThis is an Accepted Manuscript of a book chapter published by Routledge in [Early Years Science Education: A Contemporary Look] on [29/08/2018], available online: https://www.routledge.com/Early-Years-Science-Education-A-Contemporary-Look/Watts-Silby/p/book/9780367586751The acquisition of everyday scientific concepts by 3–6-year-old children attending early childhood institutions has been widely studied. In contrast, research on science learning processes among younger children is less extensive. This paper reports on findings from an exploratory empirical study undertaken in a ‘stay and play’ service used by parents with children aged 0–3 and located within an East London early childhood centre. The research team collaborated with practitioners to deliver a programme of activities aimed at encouraging parents’ confidence in their own ability to support emergent scientific thinking among their young children. The programme generated children’s engagement and interest. Parents and practitioners reported increased confidence in their ability to promote young children’s natural curiosity at home and in early childhood provision. The authors see no reason for positing qualitative differences between the way children acquire scientific and other concepts in their earliest years.UnfundedAuthor originally uploaded VoR -embargoed for 200 years. AAM sourced and uploaded to CR and VoR removed 26/02/202
'Why do we have to learn this?’ A physics educator’s response to every teacher’s least favourite question
No full textThis is a blog post.In his years as a physics teacher, students often asked Mark Whalley why they had to learn the subject when most of them would never directly use it in their careers. Having never been satisfied with the answers he gave, he sets out the case for learning physics, even for students who don't pursue the subject further.N/
Adventures in the Play-Ritual Continuum
No full textThe junctions between play and ritual are many and complex. Play is for fun and joy, but it also demands a total commitment and serious respect for rules. Rituals involve nearly endless varieties of social arrangements and can truly transform people, but they also include improvisation, testing, and pretending.
Adventures in the Play-Ritual Continuum explores the connectivity between the playful and the ritualized through a fresh theoretical perspective, highlighting the creative messiness and the cultural paradoxes such intersections allow. The chapters span topics such as hen parties, marriage proposals, ash scatterings, extreme sports races, football fans, computer game festivals, celebrations of fandom, migration heritages, and antiracist protests. While the case studies are selected to show a range of diversity with various mergings of play, game, ritual, ceremony, rite, and ritualizing, the introductory and concluding discussions offer sharpened perspectives on common aspects.
Following these excursions through the play-ritual continuum will be enjoyable for readers interested in how people make sense of their own existence and profitable for scholars in folklore, anthropology, religion, pedagogy, cultural studies, and social sciences and humanities more generally.N/
When YouTubers launch a sports drink: A social network analysis case study of the virality related to Prime Hydration
No full textWhen entertainment influencers launch products like sports drinks, it often leads to significant online conversations that shape public perception and consumer behaviour. This case study examines such discussions surrounding Prime Hydration on X (formerly Twitter) from December 2022 using Social Network Analysis (SNA). A total of 1,562 tweets were retrieved from d posted by 1,536 Twitter users. The analysis identifies two main groups: isolated users sharing individual opinions, sometimes questioning the hype and central influencers KSI and Logan Paul, whose posts drove widespread engagement. The most active discussions during our time period were in the United Kingdom and North America, where the product was heavily promoted and readily available at retailers. Australia and Southeast Asia showed moderate interest, while Africa and South America had less activity, potentially reflecting varying levels of market penetration. Our research highlights how SNA can effectively map social media conversations, offering valuable insights into the influence of key users and global consumer reactions. The findings emphasize how influencer-driven marketing significantly impacts public dialogue and regional brand visibility, underscoring the importance of credibility and authenticity of social media influencers.N/
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