Laboratory Conditions Research Articles

Preference and Toxicity of Sulfoxaflor, Flupyradifurone, and Triflumezopyrim Bait against the Fire Ant Solenopsis invicta (Hymenoptera: Formicidae) and Their Efficacy under Field Conditions.

The red imported fire ant Solenopsis invicta Buren (Hymenoptera: Formicidae) is native to South America; however, its introduction to other countries has caused serious biodiversity, agricultural, and public health problems. As toxic bait is an effective method to control fire ant populations, the aim of this study was to determine the most effective concentration of sulfoxaflor, flupyradifurone, and triflumezopyrim as ingredients for baits against S. invicta under laboratory and field conditions. Sulfoxaflor, flupyradifurone, and triflumezopyrim had no effect on the feeding behavior of the fire ants. However, they significantly reduced the climbing, walking, and arrest abilities of the fire ant workers after 10 days of treatment, and insecticides were horizontally transferred from workers to alates or larvae. Specifically, sulfoxaflor and triflumezopyrim at 0.05% concentration were the most effective in exterminating fire ants. Sulfoxaflor and triflumezopyrim are nonrepellent and effective insecticides against S. invicta.

Chemical Diversity of Aspergillus alliaceus Phenotypes: Discovery of Brominated Bianthrones with Activity against Triple-Negative Breast Cancer Cell Lines.

Marine-derived fungi have emerged as a source for novel metabolites with a broad range of bioactivities. However, accessing the full potential of fungi under standard laboratory conditions remains challenging. LC-MS-based metabolomics in combination with varied culture conditions is a fast and powerful tool to detect new metabolites. Here, three developmental forms of the marine-derived fungus Aspergillus alliaceus were analyzed and 14 fungal metabolites, including new brominated polyketides (11-14) were isolated. Structure elucidation relied mainly on 1D and 2D NMR techniques and was supported by low- and high-resolution mass spectrometry and DFT-based computations. We sequenced the A. alliaceus genome, identified the bianthrone-producing biosynthetic gene cluster, and conducted expression analysis on genes involved in sexual development and biosynthesis. The NCI-60 cell line panel revealed selective in vitro activity against triple-negative breast cancer (TNBC) for the halogenated allianthrones and their full antiproliferative and cytotoxic effects were evaluated in five TNBC cell lines.

Toxicity and deterrence of pyroligneous extracts on Liriomyza sativae (Diptera: Agromyzidae)

Liriomyza sativa is a cosmopolitan and polyphagous insect, a key pest of crops such as tomato and melon. The inadequacy of insecticide application techniques has developed resistant populations. The objective of this research was to evaluate the toxicity, insecticidal activity and deterrence of pyroligneous extracts on the leafminer fly. The experiments were carried out under laboratory conditions of 25 ± 2°C and humidity of 60 ± 10%. For the toxicity test, solutions were prepared in different concentrations by diluting them in distilled water. Leaf discs containing L. sativae larvae were immersed in the solutions. For insecticidal activity and deterrence tests, jack bean plants were subjected to application of treatments using an airbrush, spraying 6 mL of the solutions on each plant. All extracts showed significant mortality for the larvae, with emphasis on the pyroligneous extract of coffee straw at 350ºC. The extracts did not interfere with the other developmental stages of the leafminer fly. The pyroligneous extract from the commercial company Agttec and the coffee straw extract at 600ºC were classified as attractive and the coffee straw extract at 350ºC as detergent. It is concluded that pyroligneous extracts can be used in the management of L. sativae.

Exposure to Lead (Pb) influences the outcomes of male-male competition during precopulatory intrasexual selection

Male-male competition is a component of Darwin’s theory of precopulatory intrasexual selection, where males compete for access to resources important for reproduction and successful males pass on traits that endow greater competitive ability to their offspring, thereby exaggerating the trait(s) over evolutionary time. Metals, such as lead (Pb) often occur in urban mangrove forests, where shore crabs reside, and being neurotoxic may cause sub-lethal effects on behaviour. In this study, we asked whether exposure to Pb influences the outcomes of male-male competition in the Semaphore crab, Heloecius cordiformis, thereby altering outcomes of intrasexual selection. Crabs were exposed to an environmentally relevant, and a behaviourally relevant, concentration of lead (i.e. Pb, 10 µg/L and 100 µg/L respectively) under laboratory conditions for 96 h and subsequently allowed to compete for burrow ownership in experimental arenas. Exposed crabs (100 µg/L) were less successful than control crabs in chela size-matched paired competitive interactions, spent less time in burrows and predominantly lost burrow ownership. Further, exposure to Pb contamination (both 10 µg/L and 100 µg/L) negated the chela size advantage in size-asymmetric competitive interactions. This contaminant-induced loss of size-related competitive advantage may result in relaxation in selection pressure on body size and smaller male carapace widths and especially male chela lengths in contaminated locations. Assessment of a range of locations in the wild found a consistent pattern of metal-associated size declines in more contaminated locations for males, but not for females.

Eco-friendly formulation preparation of fungal biopesticide Metarhizium anisopliae and its impact on the viability, insecticidal activity and pesticidal compatibility

Aim: The present investigation evaluated the effect of various formulations on the viability, pesticide compatibility and biocontrol potential of fungal biopesticidal agent Metarhizium anisopliae under laboratory conditions. Methodology: Soil isolate of M. anisopliae biomass was formulated with different oils like sunflower, groundnut, neem oil, water and diesel using green principles. Results: Sunflower oil recorded maximum viability among the formulations, revealing 91.4% formulation efficacy, followed by groundnut oil, which showed 87.2% efficacy. The viability of the fungal isolate was found to be low in diesel formulation, which showed 69.2% formulation efficacy. A compatibility study revealed that sunflower oil formulation showed high tolerance to all the tested pesticides. Sunflower oil formulation also showed a high rate of mortality against S. litura. Interpretation: The present study suggests using oil formulation as an effective carrier for the fungal biopesticide Metarhizium anisopliae with high compatibility and viability. Key words: Biopesticide, Fungal strains, Metarhizium anisopliae, Sunflower oil

The metamorphosis of amphibian myocardium: moving to the heart of the matter.

Amphibians are a classical object for physiological studies, and they are of great value for developmental studies owing to their transition from an aquatic larval form to an adult form with a terrestrial lifestyle. Axolotls (Ambystoma mexicanum) are of special interest for such studies because of their neoteny and facultative pedomorphosis, as in these animals, metamorphosis can be induced and fully controlled in laboratory conditions. It has been suggested that their metamorphosis, associated with gross anatomical changes in the heart, also involves physiological and electrical remodeling of the myocardium. We used whole-cell patch clamp to investigate possible changes caused by metamorphosis in electrical activity and major ionic currents in cardiomyocytes isolated from paedomorphic and metamorphic axolotls. T4-induced metamorphosis caused shortening of atrial and ventricular action potentials (APs), with no changes in resting membrane potential or maximum velocity of AP upstroke, favoring higher heart rate possible in metamorphic animals. Potential-dependent potassium currents in axolotl myocardium were represented by delayed rectifier currents IKr and IKs, and upregulation of IKs caused by metamorphosis probably underlies AP shortening. Metamorphosis was associated with downregulation of inward rectifier current IK1, probably serving to increase the excitability of myocardium in metamorphic animals. Metamorphosis also led to a slight increase in fast sodium current INa with no changes in its steady-state kinetics and to a significant upregulation of ICa in both atrial and ventricular cells, indicating stronger Ca2+ influx for higher cardiac contractility in metamorphic salamanders. Taken together, these changes serve to increase cardiac reserve in metamorphic animals.

National recommendations of the Croatian Chamber of Medical Biochemists and Working group for Laboratory hematology of the Croatian Society of Medical Biochemistry and Laboratory Medicine: Management of samples with suspected EDTA-induced pseudothrombocytopenia.

Pseudothrombocytopenia (PTCP) is defined by the occurence of spouriously low platelet count as a consequence of in vitro platelet aggregation. It is a rare and benign artifact, not associated with any specific disorder or therapy, that becomes clinically relevant when it is not timely and reliably recognized. Thus, it may result in inappropriate clinical decisions (i.e. unnecessary further testing, misdiagnoses and potential patients' mismanagement) unavoidably compromising patient safety. The most common form of PTCP is caused by ethylenediaminetetraacetic acid (EDTA). Several approaches for the management of samples with EDTA-induced PTCP have been described in the literature. However, expert recommendations are scarce. The scope of these recommendations is to assist in achieving national harmonisation in laboratory management (i.e. detecting and reporting platelet counts) of samples with EDTA-induced PTCP. These minimal recommendations were prepared by the members of the joint working group of the Croatian Chamber of Medical Biochemists and Working group for Laboratory Hematology of the Croatian Society of Medical Biochemistry and Laboratory Medicine, and might be customized according to specific conditions (i.e. personnel and equipment) of each individual laboratory. These recommendations are primarily intended to all laboratory professionals involved in the management of samples with EDTA-induced PTCP, but also to other healthcare professionals involved in collecting samples and interpreting complete blood count results.

Isolation, Identification and Evaluation of the Effective Phyto-Compounds for The Management of Groundnut Beetles Infesting Stored Groundnut (Arachis Hypogaea L.)

The effectiveness of various botanicals was tested against the Major Pest of shelled groundnuts, the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenbebrionidae), under artificial infestation, in Laboratory conditions for one year. Essential Oils isolated by Clevengers Apparatus , @1%v/w of Pongamia glabra (Karanja Oil), Azadirachta indica (Neem Oil), Brassica campestris (Mustard Oil) , Crown oil (Resin of Shorea robusta) , Dalbergia sisso (Sisso Oil), Oryza sativa (Rice bran oil), Helianthus annus (Sunflower Oil) , Ricinus communis (Castor Oil), Aegle marmelos (Bael Oil), Sesamum indicum (Til Oil), etc were tested for their bioefficacy against the Major Pest, of shelled groundnuts, red flour beetle Tribolium castaneum, (Herbst) Tenebrionidae, Coleoptera, under artificial infestation, in Laboratory conditions for one year. Out of all these plant products only, Crown oil (Resin of Shorea robusta) gave 100 % pod/Kernel protection for one year. The LD 50 values were found out to be - 0.5% v/w. Spectroscopic GC MS analysis of, Crown oil (Resin of Shorea robusta) are identified as 2-Ethyl-oxetane (RT 2.223), as the major product It may be due to the strong aromatic nature of these phyto-product. Hence these phyto-product may be used as fumigants or insect repellants against Tribolium castaneum and can be included in the package of practices to save stored groundnut in storage.

Effects of Pirimiphos-Methyl on Non-Target Invertebrates.

The effects of pirimiphos-methyl have previously been assessed on blood-sucking insect species, pollinating insects, and target crop pest species. The sensitivity of non-target zoophagous and saprophage species to this insecticide remains largely unstudied. In laboratory conditions, we assessed the susceptibility of 43 species of invertebrates to pirimiphos-methyl. The most tolerant species to this insecticide were Pyrrhocoris apterus (LC50 measured over 60 mg/m2), Cylindroiulus truncorum, Pterostichus niger, Harpalus rufipes, Lithobius forficatus, and Carabus hortensis (LC50 ranged from 25 to 50 mg/m2). Average tolerance to pirimiphos-methyl was displayed by Ophonus rufibarbis, Teuchestes fossor, Silpha carinata, Badister sodalis, Rugilus rufipes, Phosphuga atrata, Porcellio laevis, Pterostichus oblongopunctatus, Aphodius foetens, Lasius fuliginosus, Oxypselaphus obscurus, Platydracus fulvipes, Myrmica ruginodis, Xantholinus tricolor, and Megaphyllum sp. (LC50 for those species ranged from 12 to 24 mg/m2). Higher sensitivity to this insecticide was seen for Amara nitida, Leistus ferrugineus, Harpalus xanthopus winkleri, Philonthus nitidus, Pterostichus melanarius, Harpalus latus, Limodromus assimilis, Philonthus decorus, Tachinus signatus, Ponera coarctata, Carabus convexus, Philonthus coprophilus, Philonthus laevicollis, Platydracus latebricola, Labia minor, and Carabus granulatus (LC50 for those species ranged from 6 to 12 mg/m2). The greatest sensitivity to pirimiphos-methyl was observed in Hister fenestus, Drusilla canaliculata, Bisnius fimetarius, Oxytelus sculptus, Lasius niger, and Lasius flavus (LC50 ranged from 0.4 to 6 mg/m2). We found a relationship between the parameters of bodies of invertebrates (the average body length and dry body mass) and sensitivity to pirimiphos-methyl. With an increase in body sizes of invertebrates, the tolerance to the insecticide increased (per each mm of body length, LC50 increased by 0.82 mg/m2 on average). We identified no relationship between the trophic specialization and sensitivity to the insecticide.

Diagnostic serology test comparison for Q fever and Rift Valley fever in humans and livestock from pastoral communities.

Q fever (QF) and Rift Valley fever (RVF) are endemic zoonotic diseases in African countries, causing significant health and economic burdens. Accurate prevalence estimates, crucial for disease control, rely on robust diagnostic tests. While enzyme-linked immunosorbent assays (ELISA) are not the gold standard, they offer rapid, cost-effective, and practical alternatives. However, varying results from different tests and laboratories can complicate comparing epidemiological studies. This study aimed to assess the agreement of test results for QF and RVF in humans and livestock across different laboratory conditions and, for humans, different types of diagnostic tests. We measured inter-laboratory agreement using concordance, Cohen's kappa, and prevalence and bias-adjusted kappa (PABAK) on 91 human and 102 livestock samples collected from rural regions in Chad. The serum aliquots were tested using ELISA in Chad, and indirect immunofluorescence assay (IFA) (for human QF and RVF) and ELISA (for livestock QF and RVF) in Switzerland and Germany. Additionally, we examined demographic factors influencing test agreement, including district, setting (village vs. camp), sex, age, and livestock species of the sampled individuals. The inter-laboratory agreement ranged from fair to moderate. For humans, QF concordance was 62.5%, Cohen's kappa was 0.31, RVF concordance was 81.1%, and Cohen's kappa was 0.52. For livestock, QF concordance was 92.3%, Cohen's kappa was 0.59, RVF concordance was 94.0%, and Cohen's kappa was 0.59. Multivariable analysis revealed that QF test agreement is significantly higher in younger humans and people living in villages compared to camps and tends to be higher in livestock from Danamadji compared to Yao, and in small ruminants compared to cattle. Additionally, RVF agreement was found to be higher in younger humans. Our findings emphasize the need to consider sample conditions, test performance, and influencing factors when conducting and interpreting epidemiological seroprevalence studies.

Prototype of a New Head Grabber for Robotic Strawberry Harvesting with a Vision System

This paper presents the design of a strawberry fruit head gripper unit, together with the concept of a control system for the operation of its mechanisms and vision system. The developed design consists of three specialised mechanisms: positioning, grasping, and cutting off of the fruit. A Finite Element Method (FEM) model was developed for the described design. Next, calculations were carried out, based on which the construction materials were selected. The key performance parameters of the functional model, built on the basis of the developed design concept, were verified under laboratory conditions. In tests carried out on the possible hematoma caused by exceeding the breaking stress induced by the pressure of the encompassing jaws on the fruit, it was found that none of the fruit tested suffered mechanical damage as a result of the sensor triggering force, and the average length of the trimmed stalk was approximately 14 mm. The designed head gripper, together with the proposed automation system, will contribute to improving harvesting precision, and this will favour a reduction in the quantitative and qualitative losses of the harvested crop. The experimental tests conducted under harvesting conditions showed a high efficiency of 95% in identifying ripe fruit, and the harvesting efficiency of the robotic arm was 90%.

Acylsugars, Nicotine and a Protease Inhibitor Provide Variable Protection for Nicotiana benthamiana in a Natural Setting.

Plants produce an immense diversity of defensive specialized metabolites. However, despite extensive functional characterization, the relative importance of different defensive compounds is rarely examined in natural settings. Here, we compare the efficacy of three Nicotiana benthamiana defensive compounds, nicotine, acylsugars and a serine protease inhibitor, by growing plants with combinations of knockout mutations in a natural setting, quantifying invertebrate interactions and comparing relative plant performance. Among the three tested compounds, acylsugars had the greatest defensive capacity, affecting aphids, leafhoppers, spiders and flies. Nicotine mutants displayed increased leafhopper feeding and aphid colonization. Plants lacking both nicotine and acylsugars were more susceptible to flea beetles and thrips. By contrast, knockout of the serine protease inhibitor did not affect insect herbivory in the field. Complementary experiments under controlled laboratory conditions with caterpillars, grasshoppers and aphids confirmed results obtained in a natural setting. We conclude that the three metabolite groups collectively provide broad-spectrum protection to N. benthamiana. However, there is a gradient in their effects on the interacting invertebrates present in the field. Furthermore, we demonstrate that, even if individual metabolites do not have a measurable defensive benefit on their own, they can have an additive effect when combined with other defensive compounds.

How can ethology inform the neuroscience of fear, aggression and dominance?

The study of behaviour is dominated by two approaches. On the one hand, ethologists aim to understand how behaviour promotes adaptation to natural contexts. On the other, neuroscientists aim to understand the molecular, cellular, circuit and psychological origins of behaviour. These two complementary approaches must be combined to arrive at a full understanding of behaviour in its natural setting. However, methodological limitations have restricted most neuroscientific research to the study of how discrete sensory stimuli elicit simple behavioural responses under controlled laboratory conditions that are only distantly related to those encountered in real life. Fortunately, the recent advent of neural monitoring and manipulation tools adapted for use in freely behaving animals has enabled neuroscientists to incorporate naturalistic behaviours into their studies and to begin to consider ethological questions. Here, we examine the promises and pitfalls of this trend by describing how investigations of rodent fear, aggression and dominance behaviours are changing to take advantage of an ethological appreciation of behaviour. We lay out current impediments to this approach and propose a framework for the evolution of the field that will allow us to take maximal advantage of an ethological approach to neuroscience and to increase its relevance for understanding human behaviour.

Eco-Friendly Concrete with Improved Properties and Structure, Modified with Banana Leaf Ash

The reduction of carbon footprint, the recycling of agricultural waste, and the development of novel environmentally friendly building materials are urgent matters that necessitate innovative solutions. The objective of this study is to explore the feasibility of utilizing banana leaf ash (BLA) as a partial substitute for cement in conventional density concrete technology. The BLA-modifying additive was produced under laboratory conditions. Its chemical, phase and granulometric composition was assessed. To determine the degree of effectiveness of BLA, eight concrete compositions were developed, where the BLA content varied from 0% to 14% with an interval of 2%. The properties of fresh concrete, such as density and slump, as well as compressive strength, flexural strength, water absorption, and microstructure of hardened concrete, were studied. It has been determined that the BLA additive exhibits pozzolanic activity, with a SiO2 content of 50.83%. It is recommended that the replacement of cement with BLA does not exceed 10% for optimal results. Concrete modified with 6% BLA had the best properties and structure. The study revealed a significant 7.42% increase in compressive strength, a 7.01% increase in flexural strength, and a notable 9.28% decrease in water absorption. Thus, the obtained result proves the possibility of using BLA as a modifying additive in the technology of cement composites. The developed concrete has improved properties and is a more environmentally friendly building material than conventional concrete.

A comparative analysis of face and object perception in 2D laboratory and virtual reality settings: insights from induced oscillatory responses.

In psychophysiological research, the use of Virtual Reality (VR) for stimulus presentation allows for the investigation of how perceptual processing adapts to varying degrees of realism. Previous time-domain studies have shown that perceptual processing involves modality-specific neural mechanisms, as evidenced by distinct stimulus-locked components. Analyzing induced oscillations across different frequency bands can provide further insights into neural processes that are not strictly phase-locked to stimulus onset. This study uses a simple perceptual paradigm presenting images of faces and cars on both a standard 2D monitor and in an immersive VR environment. To investigate potential modality-dependent differences in attention, cognitive load, and task-related post-movement processing, the induced alpha, theta and beta band responses are compared between the two modalities. No evidence was found for differences in stimulus-dependent attention or task-related post-movement processing between the 2D conditions and the realistic virtual conditions in electrode space, as posterior alpha suppression and re-synchronization of centro-parietal beta did not differ between conditions. However, source analysis revealed differences in the attention networks engaged during 2D and 3D perception. Midfrontal theta was significantly stronger in laboratory conditions, indicating higher cognitive load than in the VR environment. Exploratory analysis of posterior theta showed stronger responses in VR, possibly reflecting the processing of depth information provided only by the 3D material. In addition, the theta response seems to be generated by distinct neuronal sources under realistic virtual conditions indicating enhanced involvement of semantic information processing and social cognition.

Characterization and Evaluation of an Electrostatic Knapsack Sprayer Prototype for Agricultural Crops

Pesticide application development has grown exponentially in recent decades thanks to the implementation of new technologies and improved quality of spray input application. Electrostatic technology for increasing deposition has proven to be a suitable tool under specific study conditions, such as when working with very small droplet sizes, with air assistance, or typically in greenhouse environments. However, its effectiveness in hydraulic spraying, as well as its application from a commercial point of view in agriculture, is still challenging. The aim of this study was to evaluate the performance of this technology by implementing a modified lance on a small commercial knapsack sprayer, equipped with a hydraulic nozzle providing a range of droplet size values (Dv50) from 136 μm to 386 μm in the pressure range between 2 and 6 bar. This setup allowed operation under normal conditions (disconnected electrostatic system: NES) or with the connected electrostatic system (ES), with both configurations being tested in this study. Liquid distribution profiling as well as qualitative and quantitative evaluation of deposition were carried out both under laboratory conditions and in tomato crops under greenhouse conditions. The results showed no differences between the ES and NES in terms of flow rate (L min−1) characterization or in the total accumulated volume collected with the vertical bench. The impact of the electrostatic system connection was clearly observed in laboratory trials, with total deposition increases of up to 66%. In field trials, this effect decreased in unexposed areas and in denser sections of the crop. However, the overall increase in deposition, mainly associated with the exposed side, continued to be significant.

Unravelling the threat of contamination in elite sports: Exploring diverse sources impacting adverse analytical findings and the risk of inadvertent exposure to prohibited substances

In recent years, increasing concerns have emerged regarding athletes being exposed to various sources of contamination that could result in an adverse analytical finding (AAF), which is considered a positive doping test and may lead to the athlete's sanction. This review aims to examine the potential sources of contamination. Firstly, exogenous sources such as food, water, supplements, and medications will be described, along with endogenous sources, primarily arising from the athlete’s physiological condition via the biotransformation of Medications. Finally, other hypothetical contaminations arising from sample collection procedures, poor transport or storage, and laboratory conditions will be discussed. Despite some legislative efforts to regulate the production of food and supplements, contamination remains a significant concern in the context of anti-doping, necessitating athletes to stay vigilant against the risks of inadvertent uptake of illicit products. Increased knowledge of the potential sources of contamination is essential for all parties involved in the fight against doping, including athletes, support personnel, legitimate supplement product manufacturers, and the anti-doping and scientific community. Such insights can contribute to developing the most effective strategy for preventing contamination and, most importantly, reducing the risk of inadvertent AAFs.

The analysis of the operating conditions of a heavy-duty engine of a vehicle designated for timber transport in terms of compliance with the RDE procedures

According to the data provided by Polish Central Statistical Office, the years 2000–2020 have seen a general increase in the amount of extracted timber reaching 43%. The process of obtainment and transport of timber has many stages involving multiple vehicles and machines. The prevailing type of machinery are HDVs (heavy-duty vehicles). Their application is dictated by the fact that high tonnage-rated vehicles are characterized by the greatest efficiency. The vehicles from this group are homologated under laboratory and actual traffic conditions. It is noteworthy that the transport process of timber takes place under extremely varied conditions – paved urban and rural roads a well as unpaved forest tracks. This renders the mode of operation non-compliant with the conditions set forth in the UE 582/2011 standard. Therefore, the authors decided to carry out an analysis of the operating conditions of a vehicle fitted with an HD engine used in the process of timber transport in terms of its compliance with the RDE (Real Driving Emissions) procedures. The analysis was performed based on investigations carried out under actual traffic conditions with the use of the PEMS equipment. The research object was a tractor-trailer fitted with removable stanchions and a crane used for timber handling. The paper presents, inter alia, the engine operating time share characteristics as a function of engine load and speed. The authors also compared the real-world engine operating conditions with the assumptions of the RDE procedures.

Effect of Plant Growth Regulators on Germination and Seedling Growth of Passiflora alata and Passiflora edulis

The yellow (Passiflora edulis) and sweet (Passiflora alata) passion fruit plants hold significant economic importance in tropical fruit cultivation, valued not only for the quality of their fruit but also for their medicinal properties. Conventional propagation through seeds faces challenges due to irregular and slow germination, affecting the time required for seedling formation and the viability and uniformity of plantations. The use of plant growth regulators has been explored as a strategy to overcome these barriers, improving both the rate and uniformity of seed germination. This study aimed to evaluate the influence of seed imbibition with plant growth regulators on the germination and subsequent growth of yellow and sweet passion fruit seedlings. Gibberellic acid (GA3) and GA4+7 combined with 6-benzyladenine (GA4+7+6BA) were applied in five different concentrations (0, 250, 500, 750, and 1000 mg L−1 a.i.). The experiments were conducted in both laboratory and greenhouse conditions, following a completely randomized design with a 2 × 5 factorial scheme. The varieties tested were ‘BRS Mel do Cerrado’ for sweet passion fruit and ‘IAC-275’ for yellow passion fruit. Quantitative parameters, such as germination percentage, germination speed index, fresh and dry biomass of roots and shoots, and enzymatic activity, were assessed. The results indicated that GA3, at higher concentrations, significantly enhanced both germination percentage and speed index in both Passiflora alata and Passiflora edulis when compared to the control. Additionally, seedlings treated with GA3 showed a marked increase in shoot and root biomass, particularly at concentrations of 500 and 750 mg L−1. Enzymatic assays revealed heightened catalase and peroxidase activities in treated seedlings, indicating improved stress tolerance. In contrast, the GA4+7+6BA treatment showed less pronounced effects on seedling growth. Overall, GA3 was more effective in enhancing germination and seedling growth in both species, suggesting its potential application in improving the propagation of passion fruit.

Marking Helicoverpa zea (Lepidoptera: Noctuidae) with fluorophores for use in mark-release-recapture research

Abstract Knowledge of insect dispersal and long-distance migratory flight capacity and patterns represent key factors needed for risk assessment of invasive pest species, insecticide resistance management, and more effective pest control. Having operative tools to both mark and track insect pest movement is therefore critical to achieving such goals. Here, we describe a new procedure for marking Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), one of the most economically important crop pests in the United States. Adult H. zea moths were effectively marked using the liquid fluorophore cartax green, a persistent UV-fluorescent pigment, both directly by topical application and indirectly by briefly submerging pupae in the marking solution prior to adult emergence. Regardless of the application method, the cartax mark was retained on the moths throughout their entire adult lifespan. No mortality differences were observed between cartax green-marked and water-marked (control) moths. Additionally, using rotary flight mills, we found no significant differences in several flight parameters, including total number of flights, flight speeds, flight distances, or flight durations between unmarked and cartax-marked moths. Under laboratory conditions, we did observe the lateral transfer of different colored fluorophores between moths, indicating that undesirable marking could potentially occur. Moreover, we found that not all fluorophores were equally retained on H. zea moths, with cartax green remaining intact on moths longer than did a corresponding magenta fluorophore. The results show that cartax green fluorophore could be a practical marker for H. zea and other holometabolous species targeted for large-scale mark-release-recapture research.