Effects Of Insecticides Research Articles

Effectiveness of modern antiparasitic animal collars

Despite the successes achieved in the prevention and control of parasitic diseases in companion animals, the issue of developing and implementing innovative, highly effective antiparasitic agents in veterinary practice is still relevant today. This study aimed to evaluate the efficacy of modern antiparasitic collars for dogs and cats in the prevention and treatment of ectoparasitic infections. The antiparasitic agents used in the experiments were ‘Flea and tick collar Comfort for cats’, ‘Antiparasitic collar TM Healthy Pet, Oberig’, ‘Flea and tick collar Comfort for dogs’, and ‘Antiparasitic collar TM Compliment, Oberig’. The active ingredient in the collars tested is diazinon. The experimental studies were conducted under current methodological recommendations and practical guidelines. The study of shelter pets and stray animals revealed their infestation with lice, fleas, and parasitic ticks of varying intensity. Experimentally, a high insecticidal effect of the products ‘Flea and tick collar Comfort for cats’ and ‘Antiparasitic collar TM Healthy Pet, Oberig’ was established, ‘Flea and tick collar Comfort for dogs’, ‘Antiparasitic collar TM Compliment, Oberig’ against fleas (Ctenocephalides felis, Ctenocephalides canis), chewing lice (Felicola subrostratus), sucking lice (Linognathus setosus), ticks (Ixodes ricinus, Dermacentor spp., Rhipicephalus spp.) The effectiveness of the drugs is 100%. It has been experimentally proven that the studied collars with the active ingredient diazinon can be used for preventive and therapeutic purposes for companion animals in case of infestation with fleas, chewing lice, sucking lice, and ticks

An evaluation of LLIN physical integrity and population attitudes towards net use, care and handling during the Magude project in southern Mozambique

BackgroundThe Magude Project assessed the feasibility of eliminating malaria in Magude district, a low transmission setting in southern Mozambique, using a package of interventions, including long-lasting insecticidal nets (LLINs). As the efficacy of LLINs depends in part on their physical integrity, this metric was quantified for Olyset® Nets post mass-distribution, in addition to net use, care and handling practices and other risk factors associated with net physical integrity.MethodsNets were collected during a cross-sectional net evaluation, nine months after the Magude project commenced, which was 2 years after the nets were distributed by the National Malaria Control Programme (NMCP). The physical integrity of the nets was assessed by counting and sizing the holes at different positions on each net. A structured questionnaire was administered to assess how the selected net was used and treated (care, wash and repair). Net bio-efficacy was assessed following the standard World Health Organization (WHO) cone bioassay procedures.ResultsOut of the 170 Olyset® Nets included in the analysis, 63.5% had been used the night before. The main reason for not using a net was the notion that there were no mosquitoes present. The average number of people using each net was 1.79. Two thirds of the nets had only been washed once or twice since distribution. Most nets (80.9%) were holed and 18% were torn, but none of the risk factors were significantly associated with net integrity, except for presence of mice in the household. Less than half of the participants noticed holes in holed nets, and of those only 38.6% attempted to repair those. None of the six nets that were tested for bio-efficacy passed the WHO threshold of 80% mosquito mortality.ConclusionOverall the majority of Olyset® Nets were in serviceable condition two years post-distribution, but their insecticidal effect may have been lost. This study—together with previous evidence on suboptimal access to and use of LLINs in Magude district—highlights that LLINs as an intervention could have been optimized during the Magude project to achieve maximum intervention impact.

Adulticidal Activities and Synergistic Effects of Citrus Aurantiifolia Peels and Hyptis spicigera Leaves Essential Oils against Anopheles gambiae s.l. (Diptera: Culicidae)

Research on new plant-based insecticides meets the need for an alternative to address mosquito resistance to synthetic insecticides. This study assessed the adulticidal activity and synergistic effects of essential oils (EOs) from Citrus aurantiifolia peels and Hyptis spicigera leaves on female adults of Anopheles gambiae s.l. The extraction yields were on the order of 0.17 and 0.11%, respectively, for C. aurantiifolia and H. Spicigera EOs obtained by hydrodistillation. The phytochemical composition of the EOs was analysed by Gas Chromatography coupled with Mass Spectrometry (GC-MS). GC-MS revealed that the essential oils of C. aurantiifolia and H. spicigera contained high amounts of monoterpene compounds (100% and 77.45%, respectively). Adulticidal activity was assessed using WHO and CDC bottle bioassays at concentrations of 2.5, 5, 7.5 and 10 mg/ml/btl. The EOs of both plants caused significant concentration-dependent Knock down and adulticidal activities. Individually, H. spicigera EOs had more adulticidal effects (LC50 = 4.42 mg/ml/btl) than did C. aurantiifolia EOs (LC50 = 6.79 mg/ml/btl). An EO mixture 25%Ca + 75%Hs from C. aurantiifolia and H. spicigera had synergistic effects (CI = 142.84; SF = 1.42) on female Anopheles gambiae adults. Combinations of the two plant EOs considerably optimize their insecticidal effectiveness.

Simultaneous use of Beauveria bassiana and Bacillus subtilis-based biopesticides contributed to dual control of Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) and tomato powdery mildew without antagonistic interactions

BackgroundImplementing pest and disease control techniques that have low environmental impact is important for sustainable agriculture. Microbial biopesticides are an effective approach due to their low environmental impact and low risk of resistance development. Because it is not usually possible to control multiple pests and diseases with a single microbial biopesticide, it is essential to investigate the potential for combining microbial biopesticides with varying control spectrums effectively. Many biopesticides have antimicrobial activity and may therefore interact negatively in combination.ResultsThis study demonstrated that a mixture of Beauveria bassiana and Bacillus subtilis formulations proved potential for simultaneous control of greenhouse whitefly (Trialeurodes vaporariorum Westwood) and tomato powdery mildew (Oidium neolycopersici). Three greenhouse experiments were conducted to assess the efficacy of mixed and single-use treatments. A laboratory experiment comparing the insecticidal effect of each treatment was also conducted. In all greenhouse experiments, the combined treatment controlled the greenhouse whitefly (78.9–88.3%) and tomato powdery mildew (47.2–81.0%) compared to untreated controls, which was as well as each treatment alone. In some greenhouse and laboratory experiments, the mixed treatment showed an approximately 1.32 to 1.78 times higher insecticidal effect compared to single-use treatments. Regarding the control efficacy against the pest and disease, negative effects of microbial agents on each other were not observed.ConclusionsThese results demonstrated the effectiveness of concurrent use of two microbial pesticides examined on dual control of pest and disease and showed potential for improved control of certain pests. The knowledge of this work could suggest the possibility of more environmentally friendly pest control systems with the use of microbial pesticides.

Insecticidal effects of wood vinegars produced from organic wastes on harmful almond leaf bee Cimbex quadrimaculata (Müller, 1766) (Hymenoptera: Cimbicidae)

In agricultural activities, there is an increasing need for organic products as alternatives to chemical pesticides. Wood vinegar (WV, pyrolysis liquid) from these alternative potential products is produced as a result of the carbonization process in which it is obtained from organic wastes together with useful products such as energy and biochar. This study was carried out to determine the insecticidal effects of WVs produced from broiler chicken litter and nutshells on the harmful almond leaf wasp Cimbex quadrimaculata Müller, 1766 (Hymenoptera: Cimbicidae). The study was carried out in an almond orchard in Diyarbakır (Eğil district) and Elazığ (Keban district) in the 2019-2021 production seasons. WV mixed solutions (1%, 3%, 5%, 7%, 10% and 25%) were applied with a back sprayer at the beginning and end of leafing in contaminated almond orchards. The effects of the applications were determined by impact and visual control methods on the 1st, 7th, 14th and 21st. In the analysis of the obtained data, first of all, normality test was performed. In the analysis of the obtained data, the Kruskal-Wallis test was applied. In conclusion; It has been determined that WV-added solutions have a insecticidal effect against harmful almond leaf bees, and the highest decrease in the number of larvae occurs at doses of 10% to 25%. It is important to test these vinegars in different locations with more detailed studies and to conduct detailed bioecological studies depending on the climatic factors and population ecology of the pest in terms of alternative control of the pest. The data of this study contain basic data for almond integrated pest management (IPM) studies.

Effects of sublethal fipronil insecticide concentrations on fitness and abundance profile of endosymbiont microbial species Nilaparvata lugens

Abstract. Awaluddin, Dadang, Anwar R, Giyanto. 2024. Effects of sublethal fipronil insecticide concentrations on fitness and abundance profile of endosymbiont microbial species Nilaparvata lugens. Biodiversitas 25: 998-1006. Fipronil is a widely used active ingredient for controlling Nilaparvata lugens Stal. (Hemiptera: Delphacidae), but the effect exerted on fitness ratio and composition of endosymbiont microbes remain unknown. Therefore, this study aimed to investigate effects of insecticide by assessing fitness ratio and bacterial composition of endosymbionts in N. lugens before and after applying sublethal fipronil concentrations. A pair of LC15-equivalent fipronil-treated imago were introduced into treatment pots planted with rice 30 days after transplanting. Additionally, N. lugens endosymbionts were identified using full-length primers 27F and 1492R targeting the 16S rRNA gene. The results showed that fipronil application increased the total number of nymphs and fitness ratio of N. lugens in both IR64 and ciherang rice varieties. Similar observations were obtained with erythromycin application, although the differences were not statistically significant compared to the control. Fipronil application tended to cause an insignificant increase in the percentage of hatched eggs, while samples lacking this treatment contained abundant quantities of an endosymbiont, Acinetobacter soli. After applying insecticide, a significant alteration occurred in the composition of endosymbionts, with a substantial increase in Delftia acidovorans and D. lacustris, which both contributed to the enhanced fitness and tolerance of N. lugens to fipronil. These results showed the intricate interactions between bacteria and insects, as well as the mechanisms underlying insecticide resistance, thereby providing valuable insights for the development of new pest management strategies.

Biological Activities and Traditional Use of Hyptis suaveolens in Human and Veterinary Medicine: A Review

Hyptis suaveolens (H. suaveolens), known as Gros baume or sweet-smelling Hyptis, is an invasive plant from tropical regions widely used to manage human and animal ailments, such as bacterial, viral, and parasitic diseases. This study aimed to synthesize a scientific research work on the use of this medicinal plant in the traditional pharmacopeia, as well as the biological and pharmacological activities already recognized in the literature. Information for this synthesis was collected from physical (libraries and documentation centers of universities in Benin) and reliable scientific databases, such as PubMed, Google Scholar, Scopus, and Web of Science, which were queried based on the keywords related to H. suaveolens. This plant contains secondary metabolites in its aerial parts, such as leaves, and stems, which are rich in essential oils. From leaves to roots, all parts of this plant are of interest to both humans and animals to treat various pathologies. The most frequently cited diseases include asthma, panariasis, jaundice, hyperthermia, indigestion, stomach pains, nausea, colds, gall bladder infections, breast abscesses, hemorrhoids, oral-anal candidiasis, edemas, cramps, and skin infections The various aqueous and ethanolic extracts are evaluated by researchers and the biological activities are indicated in the literature. Those activities include the antibacterial, antifungal, larvicidal, antioxidant, anticholinesterase, insect repellent, and insecticidal effects. However, no toxicity resulting from the use of this plant has yet been reported in the literature. Research on H. suaveolens toxicity must be continued to gain a comprehensive understanding of its application in human and livestock health. This literature review allows the virtues and risks related to the traditional use of H. suaveolens in human and animal pharmacopeia. The various potentialities of this plant provide a lever for exploring its antiviral effects in traditional veterinary medicine in general.

A comprehensive review of ethnomedicinal approaches, phytochemical analysis, and pharmacological potential of Vitex trifolia L.

Plants, renowned for their rich reservoir of metabolites, play a pivotal role in addressing health-related issues. The Verbenaceae family stands out, showcasing immense potential in preventing and treating chronic diseases. Vitex trifolia L. (V. trifolia), a shrub with a rich history in traditional medicine, particularly in Eastern Asia, has garnered attention for its diverse therapeutic applications. This comprehensive review aims to bridge traditional knowledge and contemporary insights by investigating ethnopharmacology, phytochemistry, and pharmacological effects of V. trifolia. The keyword "V. trifolia" and its synonyms were searched within the main scientific databases including PubMed, Web of Science, ScienceDirect, Google Scholar, and Baidu Scholar (from 1974 to 2022, last search: 21.10.2023). Phytochemical analyses reveal a spectrum of secondary metabolites in V. trifolia, including terpenoids, flavonoids, lignans, phytosterols, anthraquinones, and fatty acids. Notably, terpenoids and flavonoids emerge as the main bioactive metabolites. Pharmacological studies validate its therapeutic potential, demonstrating significant antioxidant, anti-inflammatory, hepatoprotective, anticancer, anti-amnesic, antimicrobial, antiviral, anti-malaria, antispasmodic activities, and reported insecticidal effects. Despite existing literature exploring pharmacological attributes and secondary metabolites of related species, a conspicuous gap exists, specifically focusing on the pharmacological activities and novel methods of purification of pure metabolites from V. trifolia. This review aimed to fill this gap by delving into traditional medicinal applications, exploring secondary metabolites comprehensively, and providing an in-depth analysis of pharmacological effects of pure metabolites. Combining traditional uses with contemporary pharmacological insights, this article sought to serve as a crucial reference for future research and practical application of V. trifolia. This approach contributes substantially to understanding the plant, fostering scientific inquiry, and facilitating its broader application in healthcare.

Development of a Safe and Effective Bacillus thuringiensis-Based Nanobiopesticide for Controlling Tea Pests.

Mg(OH)2 was used as the nanocarrier of the Bacillus thuringiensis (Bt) Cry1Ac protein, and the synthesized Cry1Ac-Mg(OH)2 composites were regular and uniform nanosheets. Nano-Mg(OH)2 could effectively improve the insecticidal effect of the Cry1Ac protein toward Ectropis obliqua. It could enhance the damage degree of the Cry1Ac protein to intestinal epithelial cells and microvilli, induce and enrich the production of reactive oxygen species (ROS) in the midgut, and enhance the degradation of the Cry1Ac protein into active fragments. Furthermore, an anti-rinsing assay showed that the Cry1Ac-Mg(OH)2 composites were bound to the notch structure of the tea leaf surface. The retention of the Cry1Ac protein increased by 11.45%, and sprayed nano-Mg(OH)2 was rapidly absorbed by different tissues of tea plants. Moreover, nano-Mg(OH)2 and composites did not significantly affect non-target organisms. These results show that nano-Mg(OH)2 can serve as a safe and effective biopesticide carrier, which provides a new approach for stable and efficient Bt preparation.

Cumin (Cuminum cyminum L.) an export-oriented Indian seed spice with inherent nutraceutical and therapeutic attributes: A review

Cumin seeds and value-added products are used in beverages, liquors,candy, nutraceuticals, therapeutics, toiletries, perfumery and lotions. In theIndian systems of medicine, cumin finds a vital role through its essential &total oil components and various aqueous and alcoholic extracts. Cuminseeds contain volatile oil (3–4%), the primary active principles of which arecumin aldehyde, terpenes (45–50%), phenols, unsaturated and saturatedfatty acids, etc., those occur in varying fractions compensating each other,which act as a scavenger for free radicals and antioxidants. As anutraceutical, cumin seeds contain plenty of iron, magnesium, calcium,manganese, and phosphorus. The vitamins present include thiamine,riboflavin, niacin, vitamin A, C, E, K, and vitamin B6. The seedspossessdiuretic, carminative, stimulant, digestive, tonic, appetizer, stomachic andastringent properties. It is traditionally an essential critical remedial agentfor digestion, diarrhoea, leucorrhoea, eczema, atonic, flatulence,dyspepsia and abdominal pains. Phytochemicals like alkaloid, coumarin,anthraquinone, flavonoid, protein, glycoside, resin, saponin, tannin andsteroids are abundant in its seed. Cumin seed extracts bear variousmedicinal properties such as insecticidal, antimicrobial, anti-inflammatory,antioxidant, antidiabetic, anticancer, hypotensive, bronchodilator,immunological, contraceptive, aldose reductase, analgesic,alpha-glucosidase and tyrosinase inhibitory effects, etc. Thus use of cumin offerscombined advantages, providing both nutraceutical and therapeuticproperties simultaneously.

Exposure to the environmental pollutant chlorpyrifos induces hepatic toxicity through activation of the JAK/STAT and MAPK pathways

Chlorpyrifos (CHP) is an inexpensive highly effective organophosphate insecticide used worldwide. The unguided and excessive use of CHP by farmers has led to its significant accumulation in crops as well as contamination of water sources, causing health problems for humans and animals. Therefore, this study evaluated the toxicological effects of exposure to the environmental pollutant CHP at low, medium, and high (2.5, 5, and 10 mg·kg−1 BW) levels on rat liver by examining antioxidant levels, inflammation, and apoptosis based on the no observed adverse effect levels (NOAEL) (1 mg·kg−1 BW) and the CHP dose that does not cause any visual symptoms (5 mg·kg−1 BW). Furthermore, the involvement of the JAK/STAT and MAPK pathways in CHP-induced toxic effects was identified. The relationship between the expression levels of key proteins (p-JAK/JAK, p-STAT/STAT, p-JNK/JNK, p-P38/P38, and p-ERK/ERK) in the pathways and changes in the expression of markers associated with inflammation [inflammatory factors (IL-1β, IL-6, IL-10, TNF-α), chemokines (GCLC and GCLM), and inflammatory signaling pathways (NF-кB, TLR2, TLR4, NLRP3, ASC, MyD88, IFN-γ, and iNOS)] and apoptosis [Bad, Bax, Bcl-2, Caspase3, Caspase9, and the cleavage substrate of Caspase PARP1] were also determined. The results suggest that CHP exposure disrupts liver function and activates the JAK/STAT and MAPK pathways via oxidative stress, exacerbating inflammation and apoptosis. Meanwhile, the JAK/STAT and MAPK pathways are involved in CHP-induced hepatotoxicity. These findings provide a novel direction for effective prevention and amelioration of health problems caused by CHP abuse in agriculture and households.

Molecular mechanism of thiram-induced abnormal chondrocyte proliferation via lncRNA MSTRG.74.1-BNIP3 axis

Thiram, a widely used organic pesticide in agriculture, exhibits both bactericidal and insecticidal effects. However, prolonged exposure to thiram has been linked to bone deformities and cartilage damage, contributing to the development of tibial dyschondroplasia (TD) in broilers and posing a significant threat to global agricultural production. TD, a prevalent nutritional metabolic disease, manifests as clinical symptoms like unstable standing, claudication, and sluggish movement in affected broilers. In recent years, there has been growing recognition of the regulatory role of long non-coding RNA (lncRNA) in tibial cartilage formation among broilers through diverse signaling pathways. This study employs in vitro experimental models, growth performance analysis, and clinical observation to assess broilers' susceptibility to thiram pollution. Transcriptome sequencing analysis revealed a significant elevation in the expression of lncRNA MSTRG.74.1 in both the con group and the thiram-induced in vitro group. The results showed that lncRNA MSTRG.74.1 plays a pivotal role in influencing the proliferation and abnormal differentiation of chondrocytes. This regulation occurs through the negative modulation of apoptotic genes, including Bax, Cytc, Bcl2, Apaf1, and Caspase3, along with genes Atg5, Beclin1, LC3b, and protein p62. Moreover, the overexpression of lncRNA MSTRG.74.1 was found to regulate broiler chondrocyte development by upregulating BNIP3. In summary, this research sheds light on thiram-induced abnormal chondrocyte proliferation in TD broilers, emphasizing the significant regulatory role of the lncRNA MSTRG.74.1-BNIP3 axis, which will contribute to our understanding of the molecular mechanisms underlying TD development in broilers exposed to thiram.

Field Evaluation of Biological and Conventional Insecticides for Managing Multiple Insect Pests in Cotton

Abstract Cotton, Gossypium hirsutum (L.), is an economically important crop in the United States that is plagued by a complex of insect pests. Two key pests of cotton in the midsouthern United States are the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae), and bollworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae). A suite of highly effective synthetic insecticides is typically used for control of these pests. However, it is unclear how the combined management of these two insect pests with biological insecticides impacts the economics of cotton production. To address this shortcoming, we conducted a field experiment in the Mississippi Delta over 2 yr to study the effects of synthetic and biological insecticides for control of the tarnished plant bug and bollworm on cotton yield. The results indicated the control of tarnished plant bug with synthetic insecticides had the most significant impact on cotton yield and net returns. The conventional tarnished plant bug treatment also significantly increased bollworm density and damage, but these increases did not significantly alter yield or net return in non–Bacillus thuringiensis (Bt) or Bt cottons. The economic benefit of a conventional approach to tarnished plant bug control with synthetic insecticides was US$438.07/ha in non-Bt and $700.88/ha in Bt cotton relative to those treated with a biological insecticide. The biological insecticides used for this study were ineffective at significantly altering yield or net return. However, for insect management in cotton to be sustainable, alternatives must be found to complement conventional synthetic insecticides.

Biological effectiveness of insecticides in pear psylla control

Biological effectiveness of insecticides in pear psylla control

Where does the EU-path on new genomic techniques lead us?

Recently, the European Commission (EC) published a regulatory proposal on plants generated with new genomic techniques (NGTs) (5 July 2023). According to this proposal, NGT plant applications are categorized into category 1 NGT (NGT1) and category 2 NGT (NGT2) based on their molecular characteristics, which diverges from the current legislation centered around Directive 2001/18/EC. To demonstrate where the path of the proposal leads to in practice, we applied the proposed criteria for categorization to a list of NGT plant applications currently in the commercialization pipeline. Combining literature research and a descriptive statistical approach, we can show that 94% of the plant applications affected by the EC proposal, would be classified as NGT1 and thus would receive market approval without risk assessment, monitoring, and sufficient labeling provisions. The remaining 6% of applications would be classified as NGT2 plants, for which, in deviation from the current regulation, an adapted risk assessment is proposed. Screening of the intended traits in the pipeline highlights that certain NGT1 plants can pose similar environmental risks (e.g., invasiveness) to other genetically modified organisms (GMOs), as defined in Directive 2001/18/EC. For example, NGT1 applications based on RNA interference technology can exhibit insecticidal effects with potential side effects on non-target organisms (i.e., other insects). Our quantitative and case-specific elaboration of how the current EC regulatory proposal would affect the environment, health, and consumer protection will be informative for decision-makers and politicians.

Efficacy of Entomopathogens, Botanical and New Generation Insecticides Against Papaya Mealybug

The papaya mealybug is an invasive polyphagus pest species causing several economic damages to a wide range of agricultural crop. Five new generation insecticides of different groups, one botanical and one entomopathogenic fungus (Beauveria bassiana) were evaluated in laboratory for their effectiveness in reducing mealybug incidence on papaya. The present study was conducted to evaluate the toxic effect of different insecticides at different concentration against P.marginatus. Among the 7 insecticides, Imixam 70 WDG (Imidacloprid+Thiamethoxam) was the most effective insecticide followed by Ravjum 14.5 SC (Indoxacarb), Saka 25 SC (Abamectin 5% +Spirodiclofen 20%), Imixan and Biotrin 0.5% (Matrin), Tundra 20 SP (Acetameprid), Antario (Bacillus thuringiensis+Abamectin) and Beauveria bassiana, respectively.All the selected insecticides provided their highest efficacy at their maximum doses as well as within 7-9 DAT, among them two new generation insecticides e.g. Saka 25 SC (Abamectin 5% +Spirodiclofen 20%) @ 1.0 ml/L, Ravjum 14.5 SC (Indoxacarb) @ 1.0 ml/L and the botanical insecticide Biotrin 0.5% upto 7 DAT would be effective in controlling papaya mealybug considering the efficacy. To confirmation of the results, need to be tested under field condition. Bangladesh J. Nuclear Agric, 37(2): 81-88, 2023

Antagonistic and additive effect when combining biopesticides against the fall armyworm, Spodoptera frugiperda

Fall armyworm, Spodoptera frugiperda (FAW) is a cosmopolitan crop pest species that has recently become established in sub-Saharan Africa and Southeast Asia. Current FAW control is almost entirely dependent on synthetic pesticides. Biopesticides offer a more sustainable alternative but have limitations. For example, pyrethrum is an effective botanical insecticide with low mammalian toxicity but is highly UV labile, resulting in a rapid loss of efficacy in the field. Beauveria bassiana is an entomopathogenic fungus that is more persistent, but there is a time lag of several days before it causes insect mortality and leads to effective control. The combination of these biopesticides could mitigate their drawbacks for FAW control. Here we evaluated the efficacy of pyrethrum and B. bassiana as individual treatments and in combination against 3rd instar FAW. Four different combinations of these two biopesticides were tested, resulting in an antagonistic relationship at the lowest concentrations of B. bassiana and pyrethrum (1 × 104 conidia mL−1 with 25 ppm) and an additive effect for the other 3 combined treatments (1 × 104 conidia mL−1 with 100 ppm and 1 × 105 conidia mL−1 with 25 ppm and 100 ppm pyrethrum). Additionally, a delay in efficacy from B. bassiana was observed when combined with pyrethrum as well as a general inhibition of growth on agar plates. These results appear to show that this particular combination of biopesticides is not universally beneficial or detrimental to pest control strategies and is dependent on the doses of each biopesticide applied. However, the additive effect shown here at specific concentrations does indicate that combining biopesticides could help overcome the challenges of persistence seen in botanical pesticides and the slow establishment of EPF, with the potential to improve effectiveness of biopesticides for IPM.

Effects of insecticide spray drift on arthropod prey resources of birds in grasslands in Minnesota

AbstractSoybean aphid (Aphis glycines) insecticides are used throughout the Upper Midwest and Great Plains regions of North America, including the farmland region of Minnesota, USA, to combat insect pests. These broad‐spectrum, foliar spray insecticides have the potential to drift beyond target fields into nearby grassland cover where birds and other insectivores forage. Arthropods serve important roles in grassland ecology and are susceptible to mortality and sublethal effects from exposure to these pesticides. Our objective was to assess effects of soybean aphid insecticides on grassland arthropods, especially those that are important in grassland bird diets. We measured the abundance, consumable biomass, and family richness of insects and spiders in grasslands adjacent to soybean fields in an agricultural landscape. Soybean fields were treated with chlorpyrifos and lambda‐cyhalothrin, which were the 2 most common foliar pesticides used to control soybean aphids in Minnesota. We compared measures at focal sites to samples collected at reference sites adjacent to corn fields not sprayed for aphids during 3 periods in mid‐to‐late summer: 1–3 days before spraying, 3–5 days post‐spraying, and 19–21 days post‐spraying. The abundance of arthropods in focal grasslands was lower 3–5 days after pesticide applications. Coleoptera family richness at focal sites was also lower than at reference sites 3–5 days after pesticide applications. These measures 19–21 days after application were similar to pre‐spraying levels, indicating that arthropod populations rebounded during this period. Measures of consumable dry biomass, bird prey abundance, bird prey biomass, family richness of Araneae, family richness of Hemiptera, and family richness of Orthoptera were not different between focal and reference sites after spraying. Our results reveal that reductions in arthropod food abundance for grassland birds are associated with pesticide applications up to 5 days after spraying. We suggest that natural resource managers factor proximity to row crop fields and susceptibility to pesticide drift into decisions about where to add grassland cover to landscapes.

Mating behavior and responses to sublethal concentrations of imidacloprid in the predator Cyrtorhinus lividipennis.

Mating is an essential factor that governs the size of insect populations that reproduce sexually. The extensive application of insecticides has both lethal and sublethal effects on the physiology and mating behavior of insect natural enemies. The predatory bug Cyrtorhinus lividipennis is a natural enemy of planthopper and leafhopper populations in the rice ecosystem. Unfortunately, the effects of insecticides on the mating behavior of C. lividipennis are not well-understood. The mating behavior of C. livdipennis consisted of mounting, antennal touch and mating attempts, genital insertion, adjustment of posture, and separation of the mating pair. Approximately 82.5% of the C. lividipennis mating pairs displayed their first mating at 12-36 h postemergence. Mating activity occurred throughout a 24-h period, with peak activity at 12:00-14:00 h, and the mean duration of mating was 48.75 min. Sublethal exposure to imidacloprid increased mating latency. Compared with the controls, the duration of courtship, pre-mating and adjusting posture for males treated with imidacloprid were prolonged. The duration of mating for females treated with imidacloprid was prolonged relative to untreated controls. The fecundity and daily spawning capacity of females treated with imidacloprid were higher than the untreated controls. Our results provide insight into the mating process of C. lividipennis. Imidacloprid prolonged the duration of mating, which may explain the enhanced reproductive output in C. lividipennis females treated with imidacloprid. These findings will be useful in both rearing C. lividipennis and deploying this natural enemy in rice fields. © 2024 Society of Chemical Industry.

Effect of Some Ecological Factors on Stomata and Phenolic Compounds Production in Aloe Vera L. Gel and Effect Gel to the Adult of Flour Beetle: Tribolium Castaneum (Coleoptera : Tenebriodae)

This search presents the effect of some ecological factors such as (ultraviolet –B radiation , temperature , salinity ) on stomatal index and stomatal frequency and phenolic compounds after exposure to Aloe vera L. UV-B radiation , temperature and salinity . Ultraviolet – B radiation is one of the important abiotic factors that can stimulate the production of secondary metabolites, including phenolic compounds. Aloe vera (Asphodelaceae) is a medicinal plant used in Iraq for treating sunburn, wounds, and heartburn. The flour beetle: Tribolium castaneum is one of the inset causes of loss storage food yield in the world. The study aims the effect of some ecological factors such as (ultraviolet –B radiation , temperature , salinity ) on stomatal index and stomatal frequency and phenolic compounds after exposure to Aloe vera L. UV-B radiation , temperature and salinity and investigate the insecticidal and repellency effect of leaf gel for Aloe vera to estimate the percentage of the insecticidal effect for concentrations 25, 50, 75, and 100 % of alcoholic extract within seven days on adult insects. The gel in leaf exposure to UV-B radiation contained a higher diversity of phenolic compounds and flavonoids. This search showed a high percent kill for an adult with 100% of the alcoholic extract compared with control and an excellent effect of Aloe vera gel at a concentration of 50 % for a repellency effect with a value of 10.842%. Phenolic compounds showed after exposure to UV as : (dioxyflavone ,kampferol, catechuic acid, flavonol glucuronic acid, gabardine isoflavone, isoquercitrin, p-coumaric acid, hispaglabridine ) with a high percentage in the gel after exposure to UV-B compared by control.