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Impact of nectar composition and nectar yeasts on volatile emissions and parasitoid behavior
Get PDF© Crown 2025.The version of record of this article, first published in [Journal of Chemical Ecology], is available online at Publisher’s website: http://dx.doi.org/10.1007/s10886-025-01587-1Nectar yeasts can significantly influence the scent of floral nectar and therefore the foraging behavior of flower-visiting insects. While these effects likely depend on nectar chemistry and yeast species, their joint impact on nectar volatile profiles and associated insect responses remain poorly understood. Here, we used four synthetic nectar types varying in sugar and amino acid concentration and two specialist nectar yeasts (Metschnikowia gruessii and Metschnikowia reukaufii) to investigate how nectar composition and yeast species affect volatile profiles and the olfactory responses of the generalist aphid parasitoid Aphidius ervi. Olfactometer assays showed that A. ervi females significantly preferred fermented nectars with high amino acid-low sugar content (HL) and low amino acid-high sugar (LH) content, regardless being fermented by M. gruessii or M. reukaufii, over non-inoculated nectars. This effect was not observed for nectars with low amino acid-low sugar (LL) and high amino acid-high sugar (HH) content. Moreover, LL nectar fermented with M. gruessii became even repellent to the parasitoids. GC–MS analysis of volatile organic compounds (VOCs) revealed that VOC profiles of fermented nectars depended significantly on nectar type (i.e., chemical composition), yeast species, and their interaction. Whereas propyl acetate, isobutyl acetate, styrene, α-guaiene and pentyl-octanoate were associated with the LH fermented nectars, ethyl acetate and E-methyl isoeugenol were mainly associated with the HL fermented nectars, suggesting possible involvement in A. ervi attraction to these nectars. In contrast, isopropyl-hexadecanoate was associated with the non-attractive or repellent LL fermented nectars. Altogether, our results indicate that nectar composition has a strong impact on nectar scent when fermented by specialist nectar yeasts and subsequently on insect foraging behavior.This work was funded by a KU Leuven C3 grant (IOF-C32/15/020)
Bioactive volatiles From Push-Pull companion crops repel Fall Armyworm and attract its parasitoids
Get PDF© 2022 Sobhy, Tamiru, Chiriboga Morales, Nyagol, Cheruiyot, Chidawanyika, Subramanian, Midega, Bruce and Khan.Fall armyworm, Spodoptera frugiperda, is a serious invasive pest in Africa but “Push-Pull” companion cropping can substantially reduce infestation. Here, we elucidate the underpinning chemical ecology mechanisms. We hypothesized that companion crop volatiles repel herbivores (push) while attracting natural enemies (pull). Headspace volatiles collected from companion plants (Desmodium intortum, Desmodium uncinatum, Brachiaria Mulato II) were used in bioassays and electrophysiological recordings with S. frugiperda and parasitoid wasps. Insect populations, plant damage and herbivore parasitism were assessed in field plots. Coupled GC-electroantennogram (GC-EAG) recordings showed robust responses to certain aromatic and terpenoid volatile compounds. In wind tunnel bioassays, maize volatiles mixed with Desmodium volatiles were less attractive to moths than maize alone. In oviposition bioassays, S. frugiperda laid significantly fewer eggs on maize when Desmodium volatiles were present. Conversely, in an olfactometer bioassay, parasitoid wasps were attracted to the scent of both Desmodium spp. (intercrop) and the Brachiaria border crop. Our data provide evidence of the mechanisms underpinning reduced S. frugiperda infestation in the Push-Pull companion cropping system, i.e., volatiles from companion crops repel S. frugiperda while attracting its parasitoid natural enemies. These findings explain why Push-Pull field plots had fewer S. frugiperda larvae and lower crop damage than monocropped maize.This work was funded by the BBSRC Research grant BB/R020795/1 and EU FAW−IPM project (FOOD/2018/402−634). We gratefully acknowledge the financial support for icipe research by European Union, UK’s Foreign, Commonwealth and Development Office (FCDO), the Swedish International Development Cooperation Agency (Sida), the Swiss Agency for Development and Cooperation (SDC), and the Federal Democratic Republic of Ethiopia and the Government of the Republic of Kenya
Herbivore‐induced and constitutive volatiles are controlled by different oxylipin‐dependent mechanisms in rice
Get PDFThis is the peer reviewed version of the following article: [Mujiono, K., Tohi, T., Sobhy, I. S., Hojo, Y., Shinya, T., & Galis, I. (2021). Herbivore‐induced and constitutive volatiles are controlled by different oxylipin‐dependent mechanisms in rice. Plant Cell & Environment, 44(8), 2687-2699], which has been published in final form at [https://doi.org/10.1111/pce.14126]. 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.Despite the importance of volatile organic compounds (VOCs) for plants, control mechanisms for their basal and stress-induced biosynthesis and release remain unclear. We sampled and characterized headspace and internal leaf volatile pools in rice (Oryza sativa), after a simulated herbivory treatment, which triggers an endogenous jasmonate burst. Certain volatiles, such as linalool, were strongly upregulated by simulated herbivory stress. In contrast, other volatiles, such as β-caryophyllene, were constitutively emitted and fluctuated according to time of day. Transcripts of the linalool synthase gene transiently increased 1-3 h after exposure of rice to simulated herbivory, whereas transcripts of caryophyllene synthase peaked independently at dawn. Unexpectedly, although emission and accumulation patterns of rice inducible and constitutive VOCs were substantially different, both groups of volatiles were compromised in jasmonate-deficient hebiba mutants, which lack the allene oxide cyclase (AOC) gene. This suggests that rice employs at least two distinct oxylipin-dependent mechanisms downstream of AOC to control production of constitutive and herbivore-induced volatiles. Levels of the JA precursor, 12-oxo-phytodienoic acid (OPDA), were correlated with constitutive volatile levels suggesting that OPDA or its derivatives could be involved in control of volatile emission in rice.IsDB 4 in 1 Project by Ministry of Research, Technology, and Higher Education, Republic of Indonesia; Japan International Cooperation Agency; Japan Society for the Promotion of Science, Grant/Award Numbers: 16K08143, 18K05558, 24570026, P13379; Ohara Foundation, Grant/Award Number: N/
Evolutionary ecology: Plant volatile profile changes after escaping specialist insects
Get PDFConsiderable debate surrounds the role of plant volatiles in plant defence against insects. A new study provides evidence for evolutionary changes in an invasive plant that support the defensive role of plant volatiles.Unfunde
Priming of cowpea volatile emissions with defense inducers enhances the plant's attractiveness to parasitoids when attacked by caterpillars
No full textThis article is not available on ChesterRep.BACKGROUND: The manipulation of herbivore-induced volatile organic compounds (HI-VOCs) via the application of the inducers benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) and laminarin (β-1,3-glucan) is known to enhance the attractiveness of caterpillar-damaged cotton and maize plants to parasitoids. To test if this is also the case for legumes, we treated cowpea (Vigna unguiculata var. unguiculata) with these inducers and studied the effects on HI-VOC emissions and the attraction of three generalist endoparasitoids.
RESULTS: After the inducers had been applied and the plants subjected to either real or mimicked herbivory by Spodoptera littoralis caterpillars, females of the parasitoids Campoletis sonorensis and Microplitis rufiventris showed a strong preference for BTH-treated plants, whereas Cotesia females were strongly attracted to both BTH- and laminarin-treated plants with real or mimicked herbivory. Treated plants emitted more of certain HI-VOCs, but considerably less indole and linalool and less of several sesquiterpenes. Multivariate data analysis revealed that enhanced wasp attraction after treatment was correlated with high relative concentrations of nonanal, α-pinene, (E)-β-ocimene and (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), and with low relative concentrations of indole, (S)-linalool and (E)-β-farnesene. Inducer treatments had no significant effect on leaf consumption by the caterpillars.
CONCLUSION: Our findings confirm that treating cowpea plants with inducers can enhance their attractiveness to biological control agents. © 2017 Society of Chemical Industry.Swiss National Center of Competence in Research Plant Surviva
cis-Jasmone elicits aphid-induced stress signalling in potatoes
Get PDFCopyright © 2017, The Author(s). This article is published with open access at Springerlink.comElicitation of plant defense signaling that results in altered emission of volatile organic compounds (VOCs) offers opportunities for protecting plants against arthropod pests. In this study, we treated potato, Solanum tuberosum L., with the plant defense elicitor cis-jasmone (CJ), which induces the emission of defense VOCs and thus affects the behavior of herbivores. Using chemical analysis, electrophysiological and behavioral assays with the potato-feeding aphid Macrosiphum euphorbiae, we showed that CJ treatment substantially increased the emission of defense VOCs from potatoes compared to no treatment. Coupled GC-electroantennogram (GC-EAG) recordings from the antennae of M. euphorbiae showed robust responses to 14 compounds present in induced VOCs, suggesting their behavioral role in potato/aphid interactions. Plants treated with CJ and then challenged with M. euphorbiae were most repellent to alate M. euphorbiae. Principal component analysis (PCA) of VOC collections suggested that (E)-2-hexenal, (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT), (E)-β-farnesene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate (MeSA), CJ, and methyl benzoate (MeBA) were the main VOCs contributing to aphid behavioral responses, and that production of TMTT, (E)-β-farnesene, CJ, and DMNT correlated most strongly with aphid repellency. Our findings confirm that CJ can enhance potato defense against aphids by inducing production of VOCs involved in aphid-induced signalling.BB/E015794/1: Rothamsted Internationa
“The perception of visiting Holocaust sites on undergraduate students learning process”
Get PDF© Crown 2022.The version of record of this article, first published in [Innovative Higher Education], is available online at Publisher’s website: http://dx.doi.org/10.1007/s10755-022-09606-9This paper presents the main findings of a qualitative research project. The aim of the research was to explore undergraduate students’ perceived knowledge acquisition and awareness of the Holocaust, after visiting Auschwitz concentration camp in Poland. The qualitative study (focus groups & semi-structured questionnaires) involved three cohorts of students and lecturers from a university in the North West of England. The participants visited the Holocaust-related sites in Poland from 2016 to 2019. Findings indicate that students’ who actively engaged in visits to Holocaust related sites developed knowledge and awareness of the Holocaust. For many participants, this knowledge and awareness was facilitated via a reflective process that enabled empathic connection between these historical events and the students. The study also highlighted practical strategies that could be implemented to enhance the experience for future cohorts of undergraduate students visiting holocaust related sites. By adding to the limited literature on Holocaust education with undergraduate students, the study highlighted the importance and directions for future research in this area to inform future pedagogic practice.Internal Research Funding, Edge Hill Universit
Evaluation of ADAPTS-Powys (Shared Prosperity Funding)
No full textThis report is not available on ChesterRepThe Accelerating Decarbonisation and Productivity through Training and Skills (ADAPTS) programme, funded by Powys County Council's UK Shared Prosperity Fund allocation, aimed to support up to 16 businesses across various sectors in Powys. The initiative provided access to knowledge transfer, training, upskilling, and advanced manufacturing technology to enhance digital and decarbonisation competencies. Participating companies benefited from assessments and reviews conducted by engineers from AMRC Cymru, focusing on automation, manufacturing intelligence, and design. The programme sought to decarbonise operations, boost productivity, foster innovation, and elevate employee skill levels.Unfunde
SCCS Opinion on Biphenyl-2-ol and Sodium 2-biphenylolate used in cosmetic products (CAS/EC No. 90-43-7/201-993-5 and 132-27-4/205-055-6)– SCCS/1669/24
Get PDFCorrigendum to this article was published on 14th October 2025 and can be accessed here: https://www.sciencedirect.com/science/article/pii/S3050620425000545.‘Biphenyl-2-ol’ and ‘Sodium 2-biphenylolate’ (CAS/EC No. 90-43-7/201-993-5 and 132-27-4/205-055-6) are known with the INCI names ‘o-Phenylphenol’ and Sodium ‘o-Phenylphenate’, respectively, as cosmetic ingredients.
The use of o-Phenylphenol as a preservative is currently authorised in entry 7 of Annex V to the Cosmetics Regulation (EC) No.1223/2009, with a maximum concentration of 0.15 % (as phenol) in leave-on and 0.2 % (as phenol) in rinse-off cosmetic products.
The Scientific Committee on Consumer Safety (SCCS) adopted an opinion on o-Phenylphenol (OPP), Sodium o-Phenylphenate (SOPP), and Potassium o-Phenylphenate (POPP) (SCCS/1555/15) in June 2015, later revised on 15 December 2015, with the following conclusion: ‘Based on the information provided, no conclusions of safe use can be drawn for Sodium o-Phenylphenate and Potassium o-Phenylphenate’. In 2018, the SCCS released an addendum to the above scientific opinion, specifically addressing Sodium o-Phenylphenate, Potassium o-Phenylphenate, and MEA o-Phenylphenate. The SCCS concluded that ‘Due to the lack of relevant information, the SCCS is unable to answer the question regarding the safe use level of sodium-OPP, potassium-OPP, and MEA-OPP. In the SCCS's view, a direct comparison between the safety of o-Phenylphenate (OPP) and its three compounds cannot be made’. The conclusions of this opinion resulted in amending entry 7 of Annex V to the Cosmetics Regulation, removing from the list the previously authorised OPP salts.
It should be noted that o-Phenylphenol, Sodium and Potassium o-Phenylphenate are active ingredients in broad-spectrum fungicides surface biocides. Under EU biocidal Regulation (EU) 528/2012, o-Phenylphenol has been evaluated for the different product types (PTs) such as PT 1, PT 2, PT4, PT 6 as a preservative ranging from 0.1 to 0.5 % w/w.
The European Risk Assessment Committee (RAC) of ECHA issued in December 2022 an opinion recommending among others a classification for o-Phenylphenol as ‘Carcinogen of Category 2’. Following the RAC opinion, the European Commission may propose a classification for o-Phenylphenol as a ‘Carc.2’ (CLP Regulation Annex VI entry).
According to Article 15(1) of the Cosmetics Regulation ‘the use in cosmetic products of substances classified as CMR substances, of category 2, under Part 3 of Annex VI to Regulation (EC) No 1272/2008 shall be prohibited. However, a substance classified in category 2 may be used in cosmetic products where the substance has been evaluated by the SCCS and found safe for use in cosmetic products’. In view of these provisions, regulatory measures must be adopted by the Commission services within 15 months of the classification as CMR 1A or 1B of the substance(s) concerned in Part 3 of Annex VI to Regulation (EC) No 1272/2008.
In December 2023, the Commission services received a dossier to defend the safe use of o-Phenylphenol, as well as its sodium salt (CAS/EC No. 90-43-7/201-993-5 and 132-27-4/205-055-6) as preservatives in cosmetic products according to Article 15(1) of the Cosmetics Regulation 1223/2009. The Commission, therefore, requests the SCCS to carry out a safety assessment on these ingredients in view of the information provided.N/AAAM removed and VoR uploaded to CR 29/07/202
Evidence-based nursing in action: A focused ethnographic case study of knowledge use in acute care
Get PDF© 2025 The Author(s). Published by Elsevier Ltd.Introduction: Evidence-based practice (EBP) plays a crucial role in improving care outcomes in critical care settings. However, its integration into nursing practice remains challenging due to organisational hierarchies, workload pressures, and uneven access to formal knowledge. This study explores how critical care nurses access, use, and integrate knowledge, with a focus on how organisational culture, leadership, and team dynamics influence EBP implementation across two acute care sites in England.
Methods: The study adopted a focused ethnographic design, guided by Spradley’s Developmental Research Sequence. Data were collected over eight months through 210 hours of non-participant observation, 36 semi-structured interviews, and document analysis. Analysis was supported using NVivo 12, applying iterative thematic coding. Reflexivity and member checking were used to ensure analytical rigour and trustworthiness.
Results: Five central themes were identified: access to formal guidelines, the role of peer learning, organisational culture and hierarchy, the value of experiential knowledge, and barriers to EBP. While both sites demonstrated reliance on blended sources of knowledge, they differed in how organisational factors shaped access and engagement. Site A showed stronger support through mentorship, simulation-based learning, and active leadership. In contrast, Site B was marked by rigid structures and informal, inconsistent communication of evidence.
Conclusion: Critical care nurses draw on both formal evidence and informal knowledge, but the conditions of their work environment influence how and when this knowledge is used. Investment in leadership, protected learning time, and inclusive communication practices is essential to support sustainable engagement with EBP in high-pressure settings.Unfunde
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