Finger-specific effects of age on tapping speed and motor fatigability.

Introduction: Increased motor fatigability is a symptom of many neuromuscular and neurodegenerative disorders. However, it is difficult to pinpoint pathological motor fatigability, since the phenomena has not yet been fully characterized in the healthy population. In this study, we investigate how motor fatigability differs across age. Given that many disorders involve supraspinal components, we characterize motor fatigability with a paradigm that has previously been associated with supraspinal mechanisms. Finger tapping at maximal speed results in a rapid decrease in movement speed, which is a measure of motor fatigability. Methods: We collected finger tapping data in a field experiment from the general population with a smartphone app, and we investigated age differences in maximal tapping speed, as well as the decrease in tapping speed for the index, middle, and little fingers. Results: We found that the maximal tapping speed differed significantly between young (18-30 years, n = 194) and aged (50-70 years, n = 176), whereas the fatigability-induced relative decrease in movement speed did not differ between the age groups (average decrease: 17.0% ± 6.9% (young) vs. 16.5% ± 7.5% (aged) decrease). Furthermore, tapping speed and motor fatigability depended on which finger was used. Discussion: These findings might relate to dexterity, with more dexterous movements being more resistant to fatigue. In this study, we provide a characterization of motor fatigability in the general population which can be used as a comparison for clinical populations in the future.

A holistic field experimental inquiry into cadmium's migration and translocation dynamics across the entire growth spectrum of five Japonica rice cultivars.

The contamination of farmland soils with cadmium (Cd) poses a substantial threat to agricultural productivity, food security and safety, and ultimately human health. However, little research has been done on the Cd transport mechanisms in highly Cd polluted soil via field experiment. This study, from a field-scale perspective, examines the migration and transformation features of Cd throughout the growth cycle of five (C1, C2, C3, C4, H1) Japonica rice cultivars in Jiangsu Province, China. Analysis of pH, SOM, total Cd, DTPA-Cd, and microbial communities were conducted. C1 ~ C3 were classified as High Cd-accumulating rice (HC), while C4 and H1 were considered as low Cd-accumulating rice (LC) based on the Cd levels in their brown rice. Phloem was confirmed as the main pathway for Cd into rice grains in high-Cd soil. For the HC group, the Cd concentration in brown and polished rice was positively correlated with the Cd concentration in the leaves and spikes; while for the LC group, they were significantly positively correlated with the Cd concentration in both stem and spike (p < 0.05). The husks of the LC group were more effective in intercepting and sequestering Cd. It was revealed that 6 % ~ 9.09 % of the Cd content detected in the rice grains could be attributed to the internal translocation processes occurring within the plant itself, and approximately 90.91 % ~ 93.84 % of the Cd was traced back to the roots' absorption during grouting. Rice polishing decreased the Cd content from the level in the brown rice by 18 % ~ 47 %. Distinct microbial profiles separated rice rhizosphere from bulk soil, with the former favouring copiotrophs in nutrient-rich zones and the latter oligotrophs in lean conditions. This study delivers crucial data support from a field perspective for a deeper understanding and control of Cd migration and transformation processes in highly Cd-contaminated soil.

Silica Accumulation in Potato (Solanum tuberosum L.) Plants and Implications for Potato Yield Performance-Results from Field Experiments in Northeast Germany.

The potato is the most important non-cereal food crop, and thus improving potato growth and yield is the focus of agricultural researchers and practitioners worldwide. Several studies reported beneficial effects of silicon (Si) fertilization on potato performance, although plant species from the family Solanaceae are generally considered to be non-Si-accumulating. We used results from two field experiments in the temperate zone to gain insight into silica accumulation in potato plants, as well as corresponding long-term potato yield performance. We found relatively low Si contents in potato leaves and roots (up to 0.08% and 0.3% in the dry mass, respectively) and negligible Si contents in potato tuber skin and tuber flesh for plants grown in soils with different concentrations of plant-available Si (field experiment 1). Moreover, potato yield was not correlated to plant-available Si concentrations in soils in the long term (1965-2015, field experiment 2). Based on our results, we ascribe the beneficial effects of Si fertilization on potato growth and yield performance reported in previous studies mainly to antifungal/osmotic effects of foliar-applied Si fertilizers and to changes in physicochemical soil properties (e.g., enhanced phosphorus availability and water-holding capacity) caused by soil-applied Si fertilizers.

Traits estimated when grown alone may underestimate the competitive advantage and invasiveness of exotic species.

Functional differences between native and exotic species, estimated when species are grown alone or in mixtures, are often used to predict the invasion risk of exotic species. However, it remains elusive whether the functional differences estimated by the two methods and their ability to predict species invasiveness (e.g. high abundance) are consistent. We compiled data from two common garden experiments, in which specific leaf area, height, and aboveground biomass of 64 common native and exotic invasive species in China were estimated when grown individually (pot) or in mixtures (field). Exotic species accumulated higher aboveground biomass than natives, but only when grown in field mixtures. Moreover, aboveground biomass and functional distinctiveness estimated in mixtures were more predictive of species persistence and relative abundance in the field mixtures in the second year than those estimated when grown alone. These findings suggest that assessing species traits while grown alone may underestimate the competitive advantage for some exotic species, highlighting the importance of trait-by-environment interactions in shaping species invasion. Therefore, we propose that integrating multi-site or multi-year field surveys and manipulative experiments is required to best identify the key trait(s) and environment(s) that interactively shape species invasion and community dynamics.

Interaction Between Climate Change Scenarios and Biological Invasion Reveals Complex Cascading Effects in Freshwater Ecosystems.

Climate change often facilitates biological invasions, leading to potential interactive impacts of these global drivers on freshwater ecosystems. Although climatic mitigation efforts may reduce the magnitude of these interactive impacts, we are still missing experimental evidence for such effects under multiple climate change scenarios within a multi-trophic framework. To address this knowledge gap, we experimentally compared the independent and interactive effects of two climate change scenarios (mitigation and business-as-usual) and biological invasion on the biomass of major freshwater trophic groups (phytoplankton, zooplankton, periphyton, macroinvertebrates, and a native macrophyte) and the decomposition rate of allochthonous material. Among the independent effects, we found that the business-as-usual climate treatment resulted in lower native macrophyte biomass and higher periphyton biomass compared to the climatic baseline and mitigation treatments. This indicates the potential of climate change to alter the relative dominance of different freshwater producers and demonstrates that climate mitigation efforts can counteract these effects. Biological invasion alone increased the biomass of chironomids, a dominant macroinvertebrate group in tropical freshwater ecosystems, demonstrating a compensatory effect on climate change. Climate change and biological invasion interactively reduced the decomposition rate of allochthonous detritus, likely mediated by the feeding preference of abundant chironomids for periphytic algae associated with the presence of non-native macrophytes. We concluded that (i) climatic mitigation can maintain climate baseline conditions in freshwater ecosystems, and (ii) the interactive effects between future climate scenarios and biological invasion are related to complex cascading interactions among trophic groups on ecosystem processes.

Racial Minorities Face Discrimination From Across the Political Spectrum When Seeking to Form Ties on Social Media: Evidence From a Field Experiment.

We conducted a preregistered field experiment examining racial discrimination in tie formation on social media. We randomly assigned research accounts varying on race (Black, White) and politics (liberal/Democrat, conservative/Republican, neutral) to follow a politically balanced sample of Twitter (i.e., X) users (N = 5,951) who were unaware they were in a research study. We examined three predictions from the social and political psychology literatures: i) individuals favor White over Black targets, ii) this tendency is stronger for conservatives/Republicans than for liberals/Democrats, and iii) greater discrimination by conservatives/Republicans is explained by the assumption that racial minorities are liberal/Democrat. We found evidence that individuals were less likely to reciprocate social ties with Black accounts than White accounts. However, this tendency was not moderated by individuals' political orientation, shared partisanship, or partisan mismatch. In sum, this work provides field experimental evidence for racial discrimination in tie formation on social media by individuals across political backgrounds.

Factors Influencing Customer Participation in a Program to Replace Lead Pipes for Drinking Water.

Many public water systems are struggling to locate and replace lead pipes that distribute drinking water across the United States. This study investigates factors associated with customer participation in a voluntary lead service line (LSL) inspection and replacement program. It also uses quasi-experimental and experimental methods to evaluate the causal impacts of two grant programs that subsidized homeowner replacement costs on LSL program participation. LSLs were more prevalent in areas with a higher concentration of older housing stock, Black and Hispanic residents, renters, and lower property values. Owner-occupied and higher valued properties were more likely to participate in the LSL program. Results from the two grant program evaluations suggest that subsidies for low-income homeowners to cover LSL replacement costs can significantly boost participation, but only when the programs are well publicized and easy to access. Even then, there was still significant non-participation among properties with confirmed LSLs.

Social discounting in a symmetric giving and taking frame: An artifactual field experiment with young South African adults.

In the dictator game, the evidence that giving is equivalent to taking is mixed. The purpose of this study was to investigate framing effects (giving/taking) on social-discounting rates among young African adults from an informal settlement in South Africa. Employing a within-participant design, these young adults completed a series of incentivized dictator games with an isomorphically equivalent giving and taking frame at each of eight social distances. Altruism was measured by the social-discounting rate, and framing effects were assessed using generalized linear regression. The study provides empirical evidence that prosocial behavior among young South African adults is subject to framing because exponential, hyperbolic, and q-exponential social-discounting rates in all instances were lower in the taking than in the giving frame. This difference may be the result of greater "egalitarianism" and "selflessness" elicited by the taking frame, which likely is a product of the experiment's particular social and economic field context. More comparative research is required to establish the working of specific mechanics of morality that may operate differently in diverse socioeconomic contexts, thus contributing to elucidating the heterogeneous nature of findings in this area of study.

Long-term biochar and soil organic carbon stability - Evidence from field experiments in Germany.

Organic soil amendments (OSA) with long residence times, such as biochar, have a high potential for soil organic carbon (SOC) sequestration. The highly aromatic structure of biochar reduces microbial decomposition and explains the slow turnover of biochar, indicating long persistence in soils and thus potential SOC sequestration. However, there is a lack of data on biochar-induced SOC sequestration in the long-term and under field conditions. We sampled two long-term field experiments in Germany, where biochar was applied 12 and 14 years ago. Both locations differ in soil characteristics and in the types and amounts of biochar and other OSA. Amendments containing compost and 31.5 Mg ha-1 of biochar on a loamy soil led to a SOC stock increase of 38 Mg ha-1 after OSA addition. The additional increase is due to non-biochar co-amendments such as compost or biogas digestate. After eleven years, this SOC stock increase was still stable. High biochar amount additions of 40 Mg ha-1 combined with biogas digestate, compost or synthetic fertilizer on a sandy soil led to an increase of SOC stocks of 61 Mg ha-1; 38 Mg ha-1 dissipated in the following four years most likely due to lacking physical protection of the coarse soil material, and after nine years the biochar-amended soils showed only slightly higher SOC stocks (+7 Mg ha-1) than the control. Black carbon stocks on the same soil increased in the short- and mid-term and decreased almost to the original stock levels after nine years. Our results indicate that in most cases the long-term effect on SOC and black carbon stocks is controlled by biochar quality and amount, while non-biochar co-amendments can be neglected. This study proves that SOC sequestration through the use of biochar is possible, especially in loamy soils, while non-biochar OSA cannot sequester SOC in the long term.

Effects of verbatim repetition of the headline message on the proceed button on click-through rates in online retail.

For online retailers, increasing click-through rates and reducing dropout rates are critical to success. In this study, we examine the effect of verbatim repetition of the website's headline message on the proceed button, based on research on processing fluency. In our field study involving 956 online platform visitors, we found that verbatim repetitions of the header message on the proceed button resulted in an increase in the conversion rate by more than 10 percentage points compared to gist repetitions and new messages. Our findings highlight the importance of simple verbatim features and demonstrate the successful application of processing fluency research to impact consumer behavior.

Influence of partition layouts on speech privacy in open-plan offices.

Different partition layouts were compared to determine how to increase speech privacy while maintaining communication efficiency between workers in an open-plan office. A preliminary survey was used to determine current usage and conditions of partitions in open-plan offices. The survey results were used to select four partition layouts for testing: face-to-face, parallel, crossed-rod, and orthogonal. A computer modeling was used to test the partition layouts at three different partition heights: 1.2, 1.5, and 1.8 m. The modeling results showed that the parallel- and crossed-rod-type layouts offered the best speech privacy at the lowest partition height, but the differences among layouts disappeared as the partition height was increased. Furthermore, an acoustic field experiment was performed using partitions with a 1.5 m height following the ISO 3382-3 standard. The experimental results showed that the face-to-face layout resulted in the least speech privacy. Based on these results, an open-plan office needs to ensure that workers are spaced a sufficient distance apart and that they do not face each other to ensure speech privacy. Additionally, speech privacy should be considered in the design stage of the office space.

The legacy effect of long-term nitrogen fertilization on nitrous oxide emissions.

The primary driver of increasing atmospheric concentrations of nitrous oxide (N2O) is the use of organic and synthetic fertilizer to increase agricultural crop production. Current global estimates are based on IPCC N2O emission factor (EF) calculations, although there are shortcomings as many of the N2O EFs are derived from measurements during the cropping season. These neglect the fallow season, and do not adequately account for double or even triple cropping systems or legacy effects on soil N2O emissions in the following year. In this study, we assessed the legacy effect of fertilization on soil N2O fluxes using data from a long-term double-cropping field experiment with summer maize and winter wheat in rotation, in which no nitrogen (N; NN) and balanced manure with synthetic N (MN) fertilized treatments were switched to allow an assessment of legacy effects. Based on high-frequency measurements of N2O and previous data, we calculated that the historical N fertilization, or legacy effect, explained 23 % of the annual flux of 0.81 kg N ha-1 yr-1 in the first season of observation. In the following three seasons, the legacy effect of the previous N fertilization regime decreased to a negligible level, with N2O emissions mainly driven by in-season fertilization. Our data show that, on average, the seasonal EF for N2O was about 0.11 % higher in response to the previous N fertilization. Our study indicates that the current N2O EF may severely underestimate emissions because studies ignore legacy effects on N2O emissions from zero N plots and only compare zero N with N fertilization treatments for a given season or year to derive seasonal or annual N2O EF.

An experimental field study of inbreeding depression in an outcrossing invasive plant.

Inbreeding depression is likely to play an important role during biological invasion. But relatively few studies have investigated the fitness of selfed and outcrossed offspring in self-incompatible invasive plants in natural environments in their introduced range. Moreover, the majority of studies on inbreeding depression have investigated self-compatible species with mixed mating, and less is known about the intensity of inbreeding depression in outcrossing self-incompatible species. Here, we address these questions experimentally by comparing selfed and outcrossed progeny of purple loosestrife (Lythrum salicaria) over four growing seasons, including three under field conditions in a freshwater marsh in southern Ontario, Canada, a region where L. salicaria is highly invasive. The tristylous mating system of L. salicaria involves disassortative mating among floral morphs enforced by trimorphic incompatibility. However, owing to partial incompatibility, self-fertilized seed can be obtained by manual self-pollination thus facilitating comparisons of selfed and outcrossed progeny. We compared progeny with and without intraspecific competition from selfed or outcrossed neighbours and examined the influence of breeding treatment and competition on fitness correlates by measuring a range of life-history traits including: proportion of seeds germinating, days to germination, survival, proportion of plants flowering, time to flowering, vegetative mass, and inflorescence number and mass. We analysed data for each trait using functions from time series estimates of growth and two multiplicative estimates of fitness. We detected varying intensities of inbreeding depression for several traits in three of the four years of the experiment, including inflorescence mass and reproductive output. Cumulative inbreeding depression over four years averaged δ = 0.48 and 0.68, depending on the method used to estimate multiplicative fitness. The competition treatments did not significantly affect plant performance and the magnitude of inbreeding depression. Given the primarily outcrossing mating system of L. salicaria populations, the detection of inbreeding depression for several key life-history traits was as predicted by theory. Our results suggests that biparental inbreeding and low selfing in colonizing populations may have significant effects on demographic parameters such as population growth.

Re-designing a yield-improving strategy of pear orchards in the Yangtze River Basin, China.

BACKGROUND: Pear yield is a primary source of income for smallholder farmers in China, yet significant yield disparities exist among different smallholders. Systematic analyses of limiting factors and the feasibility of solutions at the smallholder level are limited. This study employs a novel DEED (Describe, Explain, Explore, and Design) research cycle centered on smallholders to formulate yield-improving strategies. RESULTS: A comprehensive survey of 173 smallholders in the Yangtze River pear district, encompassing Zhejiang province, Jiangxi province, and Shanghai city, was conducted to delineate the current yield status. The boundary line analysis model was applied to elucidate the contributions of various yield-limiting factors. Findings reveal an average yield ranging from 16.7 to 19.3 t ha-1, with a potential highest yield of 37.5 t ha-1. Fertilizer nitrogen (N) was identified as the most pervasive yield-limiting factor, constituting 62.7% of the average limitation at the regional level and 37.7% at the individual smallholder level, surpassing other yield-related factors in all three regions. Subsequently, a 2-year field optimization experiment was conducted to explore the potential for yield improvement through adjustments in N fertilizer rates. Compared with traditional farmer management (FM), the N fertilizer optimization treatment (OPT) resulted in a 38.1% and 22.5% increase in yield for 2022 and 2023, respectively. CONCLUSION: These results identify N fertilizer application rate as the most important yield-limiting factor and verify the feasibility of optimizing N fertilizer management practices for improving pear yield. This study integrates farmer surveys, boundary line models, and field experiments to provide valuable insights into addressing yield disparities among smallholders in the pear industry. © 2024 Society of Chemical Industry.

Seed Priming with Rhizospheric Bacillus subtilis: A Smart Strategy for Reducing Fumonisin Contamination in Pre-Harvest Maize.

Maize, one of the most important cereal crops in Bangladesh, is severely contaminated by fumonisin, a carcinogenic secondary metabolite produced by Fusarium including Fusarium proliferatum. Biocontrol with Bacillus strains is an effective approach to controlling this F. proliferatum as Bacillus has proven antagonistic properties against this fungus. Therefore, the present study aimed to determine how native Bacillus strains can reduce fumonisin in maize cultivated in Bangladesh, where BDISO76MR (Bacillus subtilis) strains showed the highest efficacy both in vitro in detached cob and in planta under field conditions. The BDISO76MR strain could reduce the fumonisin concentration in detached cob at 98.52% over untreated control, by inhibiting the conidia germination and spore formation of F. proliferatum at 61.56% and 77.01%, respectively in vitro. On the other hand, seed treatment with formulated BDISO76MR showed higher efficacy with a reduction of 97.27% fumonisin contamination compared to the in planta cob inoculation (95.45%) over untreated control. This implies that Bacillus-based formulation might be a potential approach in mitigating fumonisin contamination in maize to ensure safe food and feed.

Creating a resilient pedagogy: Character strengths intervention for aspiring educators.

Teachers play a crucial role in guiding learners through life's challenges. They face educational and socio-economic shifts while striving to teach for a better future. Our study focuses on equipping future teachers, called pre-service teachers, with resilience-building resources during their teacher training program. A potential antecedent to resilience, which facilitates cognitive strategies and attentional processes, is cognitive flexibility. We first tested whether cognitive flexibility predicts resilience. Next, relying on the tenets of positive psychology, which studies resilience, we developed and tested the effectiveness of character strengths intervention in enhancing pre-service teachers' resilience and cognitive flexibility. An individual's belief in their ability to change personal resources could influence how an intervention manifests. Hence, we studied how mindset impacts the intervention's effect on cognitive flexibility and, thus, resilience. We adopted a multi-method approach, guided by Polk's theory of resilience, to test out objectives. Using a cross-sectional design, study one (n = 273) found that cognitive flexibility significantly predicted resilience. Study two (N = 193; nexp = 133, ncont = 60) was a multi-site field experiment. We found that intervention significantly enhanced resilience (experimental group M = 29.62, control group M = 28.33) and cognitive flexibility (experimental group M = 54.42, control group M = 52.01). Further, a growth mindset, was found to moderate the indirect effect of character strengths intervention on resilience via cognitive flexibility. The study contributes to theoretical and practical advancements in resilience. Taken together, the findings highlight the cognitive-affective-behavioural makeup of resilience and, importantly, the role of cognitive flexibility. The intervention can be seamlessly integrated into teacher training curricula for a resilient future.

First attempt to measure macroplastic fragmentation in rivers.

Direct field measurements of macroplastic fragmentation during its transport in rivers are currently unavailable, and there is no established method to perform them. Previous studies have showed that macroplastic fragmentation results in the production of harmful microplastics, and river channels can be hotspots for this process. Therefore, obtaining information about this process is crucial for quantifying the production of secondary microplastics in rivers and assessing the related risks for riverine biota and human health. Here, we propose a simple low-cost methodology for quantifying riverine macroplastic fragmentation by conducting repeated measurements of the mass of tagged macroplastic items before and after their transport in the river. As a proof-of-concept for this method, we conducted a 52-65 day experiment that allowed us to measure a median fragmentation rate of 0.044 ± 0.012 g for 1-liter PET bottles during their transport at low to medium flow in the middle mountain Skawa River in the Polish Carpathians. Using the obtained data (n = 42), we extrapolated that during low to medium flows, the median yearly mass loss of PET bottles in the study section is 0.26 ± 0.012 g/year (0.78 ± 0.036 % of bottle mass), and the median rate of bottle surface degradation is 3.13 ± 0.14 µm/year. These estimates suggest a relatively high fragmentation rate for a PET bottle in a mountain river even under low to medium flow conditions without high-energy transport. We discuss how our simple and relatively low-cost methodology can be flexibly adapted and future optimized to quantify macroplastic fragmentation in various types of rivers and their compartments, informing future mitigation efforts about the rates of formation and dispersion of secondary microplastics.

Behavioral nudges in social media ads show limited ability to encourage COVID-19 vaccination across countries.

Behavioral nudges in Facebook ads reached nearly 15 million people across six diverse countries and, consequently, many thousands took the step of navigating to governments' vaccine signup sites. However, none of the treatment ads caused significantly more vaccine signup intent than placebo uniformly across all countries. Critically, reporting the descriptive norm that 87% of people worldwide had either been vaccinated or planned vaccination-social proof-did not meaningfully increase vaccine signup intent in any country and significantly backfired in Taiwan. This result contradicts prominent prior findings. A charge to "protect lives in your family" significantly outperformed placebo in Taiwan and Turkey but saw null effects elsewhere. A message noting that vaccination significantly reduces hospitalization risk decreased signup intent in Brazil and had no significant effects in any other country. Such heterogeneity was the hallmark of the study: some messages saw significant treatment effects in some countries but failed in others. No nudge outperformed the placebo in Russia, a location of high vaccine skepticism. In all, widely touted behavioral nudges often failed to promote vaccine signup intent and appear to be moderated by cultural context.

Remote islands as natural laboratories: human-food association increases attraction to humans and novelty exploration in a seabird.

Increased attraction to humans and their objects often arises after repeated and positive human-wildlife encounters (e.g. food provided in tourist settings). The causes of this 'over-attraction', which may result from a learned association between humans and food, are still poorly studied in wild animals. Understanding the influence of humans on animals' responses is yet crucial to prevent negative effects (e.g. aggression). We presented three novel objects to two groups of free-ranging brown skuas (Catharacta antarctica ssp. lonnbergi) in the remote sub-Antarctic, where their habitats show no or minimal human disturbance. Skuas in one group (Verte) had previously participated in repeated food-rewarded behavioural and cognitive tasks with a human experimenter; skuas in the other group (Ratmanoff) had never done so. Objects consisted of (i) one natural-food-resembling object (plastic fish), (ii) one anthropogenic food object (real cake slice), and (iii) one anthropogenic non-food object (yellow glove). Verte group skuas approached the human experimenter and pecked significantly more and sooner at novel objects. Human-food association may have thus resulted in increased attraction to humans and novelty exploration in previously naive brown skuas, making this species a useful model for investigating the consequences of experience with humans on wildlife behaviour.

The sky is not the limit: Successful foliar application of Steinernema spp. entomopathogenic nematodes to control Lepidopteran caterpillars.

Entomopathogenic nematodes (EPNs) are ubiquitous soil-thriving organisms that use chemical cues to seek and infect soil-dwelling arthropods, yielding various levels of biological control. Going beyond soil application, scientists and practitioners started exploring the option of applying EPNs onto the foliage of crops in attempts to manage leaf-dwelling insect pests as well. Despite some success, particularly with protective formulations, it remains uncertain whether EPNs could indeed survive the phyllospheric environment, and successfully control foliar insect pests. In this context, we tested the potential of commercially produced Steinernema feltiae and S. carpocapsae, two of the most commonly used EPNs in the field of biological control, in controlling Lepidopteran foliar pests of economic importance, i.e. Tuta absoluta and Spodoptera spp. caterpillars as models. We first tested the survival and efficacy of both EPN species against the Lepidopteran caterpillars when applied onto tomato, sweet pepper and lettuce leaves, under controlled conditions and in commercial greenhouse conditions, respectively. Subsequently, we explored the behavioural responses of the EPNs to environmental cues typically encountered in the phyllosphere, and analysed plant volatile organic compounds (VOCs). Our results show that both S. feltiae and S. carpocapsae successfully survived and infected the foliar caterpillars, reaching similar level of control to a standard chemical pesticide in commercial practices. Remarkably, both EPN species survived and remained effective up to four days in the phyllosphere, and needed only a few hours to successfully penetrate the caterpillars. Interestingly, S. feltiae was attracted to VOCs from tomato plants, and tended to prefer those from caterpillar-induced plants, suggesting that the nematodes may actively forage toward its host, although it has never been exposed to leaf-borne volatiles during its evolution. The present study shows the high potential of steinernematids in managing major foliar pests in greenhouses and in becoming a key player in foliar biological control. In particular, the discovery that EPNs use foliar VOCs to locate caterpillar hosts opens up new opportunities in terms of application techniques and affordable effective doses.