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Aphids that attack canola (Brassica napus L.) exhibit feeding preferences for different parts of canola plants, which may be associated with brassica-specific glucosinolates. However, this idea remains untested. Furthermore, canola aphid species employ different strategies for tolerating glucosinolates. While the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), excretes glucosinolates, the cabbage aphid Brevicoryne brassicae (L.) (Hemiptera: Aphididae) sequesters them. Given the different detoxification mechanisms, we predicted that both aphid species and aphid feeding location would affect prey suitability for larvae of the predator, Hippodamia convergens (Guérin-Méneville) (Coleoptera: Coccinellidae). We hypothesized that aphids, specifically glucosinolate-sequestering cabbage aphid, reared on reproductive structures that harbor higher glucosinolates concentrations would have greater negative effects on predators than those reared on vegetative structures which have lower levels of glucosinolates, and that the impact of aphid feeding location would vary depending on the prey detoxification mechanism. To test these predictions, we conducted experiments to compare 1) glucosinolates profiles between B. brassicae and M. persicae reared on reproductive and vegetative canola structures, 2) aphid population growth on each structure, and 3) their subsequent impact on fitness traits of H. convergens. Results indicate that the population growth of both aphids was greater on reproductive structures, with B. brassicae having the highest population growth. B. brassicae reared on reproductive structures had the highest concentrations of glucosinolates, and the greatest adverse effects on H. convergens. These findings suggest that both aphid-prey species and feeding location on canola could influence populations of this predator and, thus, its potential for biological control of canola aphids., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Insects play a crucial role in all ecosystems, and are increasingly exposed to higher in temperature extremes under climate change, which can have substantial effects on their abundances. However, the effects of temperature on changes in abundances or population fitness are filtered through differential responses of life‐history components, such as survival, reproduction, and development, to their environment. Such differential responses, or trade‐offs, have been widely studied in birds and mammals, but comparative studies on insects are largely lacking, limiting our understanding of key mechanisms that may buffer or exacerbate climate‐change effects across insect species. Here, we performed a systematic literature review of the ecological studies of lacewings (Neuroptera), predatory insects that play a crucial role in ecosystem pest regulation, to investigate the impact of temperature on life cycle dynamics across species. We found quantitative information, linking stage‐specific survival, development, and reproduction to temperature variation, for 62 species from 39 locations. We then performed a metanalysis calculating sensitives to temperature across life‐history processes for all publications. We found that developmental times consistently decreased with temperature for all species. Survival and reproduction however showed a weaker response to temperature, and temperature sensitivities varied substantially among species. After controlling for the effect of temperature on life‐history processes, the latter covaried consistently across two main axes of variation related to instar and pupae development, suggesting the presence of life‐history trade‐offs. Our work provides new information that can help generalize life‐history responses of insects to temperature, which can then expand comparative demographic and climate‐change research. We also discuss important remaining knowledge gaps, such as a better assessment of adult survival and diapause. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vegetable cultivation stands as a pivotal element in the agricultural transformation illustrating a complex interplay between technological advancements, evolving environmental perspectives, and the growing global demand for food. This comprehensive review delves into the broad spectrum of developments in modern vegetable cultivation practices. Rooted in historical traditions, our exploration commences with conventional cultivation methods and traces the progression toward contemporary practices emphasizing the critical shifts that have refined techniques and outcomes. A significant focus is placed on the evolution of seed selection and quality assessment methods underlining the growing importance of seed treatments in enhancing both germination and plant growth. Transitioning from seeds to the soil, we investigate the transformative journey from traditional soil-based cultivation to the adoption of soilless cultures and the utilization of sustainable substrates like biochar and coir. The review also examines modern environmental controls highlighting the use of advanced greenhouse technologies and artificial intelligence in optimizing plant growth conditions. We underscore the increasing sophistication in water management strategies from advanced irrigation systems to intelligent moisture sensing. Additionally, this paper discusses the intricate aspects of precision fertilization, integrated pest management, and the expanding influence of plant growth regulators in vegetable cultivation. A special segment is dedicated to technological innovations, such as the integration of drones, robots, and state-of-the-art digital monitoring systems, in the cultivation process. While acknowledging these advancements, the review also realistically addresses the challenges and economic considerations involved in adopting cutting-edge technologies. In summary, this review not only provides a comprehensive guide to the current state of vegetable cultivation but also serves as a forward-looking reference emphasizing the critical role of continuous research and the anticipation of future developments in this field. [ABSTRACT FROM AUTHOR]

The red flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) and khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) are important insect pests of stored commodities in Pakistan and other parts of the world. The laboratory study was carried out to investigate the insecticidal properties of Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) in combination with commercial diatomaceous earth (DE) formulation Inert-PMS alone and in integrate manners against these pests. Beauveria bassiana was applied at 1×106 and 1×107 conidia/ml alone, or in combination with DE at 50 and100 ppm. Adult insects were exposed to the treated wheat for 5, 10 and 15 days at 27±2 °C and 65±5% r.h. in an incubator. The mortality of Tribolium castaneum adults was 100% even after 10 days of exposure at the dosages in combination of highest dose of B. bassiana and DE. While, after last exposure 100% mortality was achieved at highest dose rate of B. bassiana and both doses of DEs. Contrarily, 100% mortality of Trogoderma granarium was recorded after 15 days of exposure at highest dose rate of B. bassiana and both DEs. The progeny emergence was significantly lower in combined treatments of B. bassiana and DE at highest dose rate for both insect species, while highest was recorded at low dose of B. bassiana. [ABSTRACT FROM AUTHOR]

Tomato spotted wilt orthotospovirus (TSWV) is destroying tomato and pepper resistance all over the world, including Antalya (Türkiye). Two greenhouses that show infection of TSWV in the Serik (coastal) and Elmali (highland) areas were chosen for research between 2019 and 2021 to better understand the disease's life cycle. During the surveys, we focused on weed hosts to better understand TSWV disease's cycle. TSWV infection was determined in 58 peppers, 34 tomatoes, 270 weeds, and 20 other vegetable samples. Weed samples revealed essentially no symptoms, however, grown plants showed classic TSWV symptoms. The Asteraceae family had the highest infection rate among infected weeds, followed by weed species from the Poaceae and Solanaceae families. In addition, to determine the viral strain in the infected plant samples, qRT-PCR and Melt-curve analysis were done using a specially designed primer pair for the study. This primer identifies the point mutation on the NSm-movement protein in the viral genome's medium segment. The non-resistance breaking isolate of TSWV was included in the optimisation studies to evaluate differences between the two isolates at two thermal melting values established by this comparison. These findings demonstrated that the kits, procedures, and primers employed in this investigation can serve as a quick and reliable diagnostic tool for identifying TSWV isolates and that weeds are a key intermediate source for new TSWV infection, as confirmed by sequence data. [ABSTRACT FROM AUTHOR]

Harmonia axyridis (H. axyridis) is the natural enemy of many aphid species. Traditional manual release of H. axyridis adults requires substantial manpower, and release efficiency is low. Automatic mechanical devices can improve the efficiency of delivery. Based on H. axyridis adults' morphological size, a prototype release system for H. axyridis was designed, which considered the adhesion characteristics of H. axyridis adults. According to the measured physical characteristics of H. axyridis adults, the structural parameters of the mechanical system for the release of the H. axyridis adults were determined. The relationship of the quantity of release, the impeller rotating speed, and the time for the release of H. axyridis adults were constructed. The mechanism can quantitatively adjust the number of H. axyridis adults to meet a certain H. axyridis-aphids ratio. Combining the image processing technology with the camera function of a mobile phone, the maximum cross-sectional area method was used to count the H. axyridis adults in the designated area. Results showed that the impeller rotating speed had a significant effect on the survival rate of the H. axyridis adults. When the airflow velocities were 29.5 m/s and 38.3 m/s, the survival rates of the H. axyridis adults were 93.8% and 94.5% at 4.2 rpm. The adhesion rate of the H. axyridis adults was 2.5%-4.6%. This work will provide technical support for the research of biological control. [ABSTRACT FROM AUTHOR]

The nutritional condition and body size influence the mating and female remating behaviour of a predaceous ladybird, Coccinella transversalis. When well-fed males were provided with females of three different dietary conditions, viz. (i) well-fed, (ii) food-deprived and (iii) honey-fed, the well-fed ones were most fecund with highest percentage of egg-viability and least preoviposition period and remating refusals, while food-deprived ones showed vice-versa. However, honey-fed females laid unfertile eggs after coercively mating with males, and resisted the most to remate, which gets strengthened in the second mating trial. This indicates females' nutritional condition modulates the females' mating behaviour and post-mating outcomes. The adult body size was directly proportional to reproductive output with heavier females showing high fecundity and percentage of egg viability with least preoviposition period than the lighter ones. Large females resisted the least to remate with larger males than with smaller males, while large males coercively mated with smaller females. Regardless of body-size, the females' remating resistance was enhanced in the second mating trial. Both diet and adult body size modulate the re-mating behaviour of female C. transversalis, as the food-deprived and large females greatly resisted to re-mate with smaller males. [ABSTRACT FROM AUTHOR]

Tomato spotted wilt (TSW) disease caused by tomato spotted wilt orthotospovirus (TSWV, Orthotospovirus tomatomaculae) poses a significant threat to specialty and staple crops worldwide by causing over a billion dollars in crop losses annually. Current strategies for TSWV diagnosis heavily rely on nucleic acid or protein-based techniques which require significant technical expertise, and are invasive, time-consuming, and expensive, thereby catalyzing the search for better alternatives. In this study, we explored the potential of Raman spectroscopy (RS) in early detection of TSW in a non-invasive and non-destructive manner. Specifically, we investigated whether RS could be used to detect strain specific TSW symptoms associated with four TSWV strains infecting three differentially resistant tomato cultivars. In the acquired spectra, we observed notable reductions in the intensity of vibrational peaks associated with carotenoids. Using high-performance liquid chromatography (HPLC), we confirmed that TSWV caused a substantial decrease in the concentration of lutein that was detected by RS. Finally, we demonstrated that Partial Least Squares-Discriminant Analysis (PLS-DA) could be used to differentiate strainspecific TSW symptoms across all tested cultivars. These results demonstrate that RS can be a promising solution for early diagnosis of TSW, enabling timely disease intervention and thereby mitigating crop losses inflicted by TSWV. [ABSTRACT FROM AUTHOR]

Environmental factors, such as the wavelength of light, can have a crucial impact on mite development. Little is, however, known about the effect of visible light quality on demographic parameters of Phytoseiidae. We therefore conducted series of laboratory experiments in which development and reproduction of Phytoseiulus persimilis Athias-Henriot feeding on Tetranychus urticae Koch eggs was investigated under various light conditions (white, blue, green, yellow, and red light). The results revealed that different light wavelengths influenced each developmental stage, with the green light conditions promoting longest pre-adult development. The longevity of both male and female mites varied significantly across light wavelengths, with the shortest lifespan observed under red light. The highest mean total fecundity, 16 eggs per female, was observed under white light conditions. Population parameters (R0, r, and λ) were also highest under white light and decreased with increasing light wavelength. These findings suggest that light wavelength plays a significant role in development, survival, and reproduction of the predatory mite, with white light being identified as providing the best light conditions for commercial production of P. persimilis. [ABSTRACT FROM AUTHOR]

The current study demonstrated the frequency and prevalence of various mite species on various vegetation types in the Egyptian governorates of Giza and Monufia. Between June 2019 and July 2021, samples were collected monthly from leaves, litter, and soil of fruit trees, vegetable crops, and ornamental plants at both locations. Leave samples were examined directly; however, soil and litter samples were extracted using modified Tullgren funnels. The mite survey revealed the occurrence of 19 predatory mite species belonging to four mesostigmatic families and three prostigmatic families. Nine of which are predatory species belong to the family Phytoseiidae and some of these predators are commercially produced as biological control agents such as Phytoseiulus persimilis Athias-Henriot, Euseius scutalis (Athias-Henriot), Neoseiulus californicus (McGregor) and Amblyseius swirskii Athias-Henriot that have been successfully applied in many countries and play an important role in control of mite pests. The presence of them is related to six species of plant-feeding mites from two families (Tetranychidae and Tenuipalpidae). In addition to three mite species with uncertain feeding habits in the family Tydeidae. The relationship between predators and pest reduction is discussed. The frequency of different mite habitats inhabiting several cultivations was mentioned as well. Obtained results are necessarily being considered in biological control decisions. [ABSTRACT FROM AUTHOR]

The aphid Rhopalosiphum maidis is a serious pest against cereal plants. In Egypt, it causes serious damage to many cereal plants. The principal idea of this study was achieved based on the observation of various seasonal invasion rates of this pest on different host plants suggesting climatic adaptation by R. maidis polymorphs. The invasion rates on winter plants were higher than those of summer. Morphologically, all collections were belonging to R. maidis. The authors assumed that different biotypes of R. maidis are present in the studied area. To address this hypothesis, the mitochondrial cytochrome oxidase I (COI) gene was amplified in aphids collected from wheat, barley, sorghum and maize in Assiut, Egypt. Polymerase chain reactions (PCR) identified 687 bps products corresponding to a partial sequence of (COI). Multiple sequence alignment of the sequenced products revealed that at least five haplotypes are present on the tested plants. Phylogenetic analysis using the neighbor-joining method identified five clades that represent different biotypes. The identified clades contained mixtures between summer and winter R. maidis collections suggesting that different biotypes are present in mixtures on the same plant. Our findings showed that R. maidis develops different polymorphs on various host plants at different climatic conditions. [ABSTRACT FROM AUTHOR]

Movement behavior is central to understanding species distributions, population dynamics and coexistence with other species. Although the relationship between conspecific density and emigration has been well studied, little attention has been paid to how interspecific competitor density affects another species' movement behavior. We conducted releases of two species of competing Tribolium flour beetles at different densities, alone and together in homogeneous microcosms, and tested whether their recaptures‐with‐distance were well described by a random‐diffusion model. We also determined whether mean displacement distances varied with the release density of conspecific and heterospecific beetles. A diffusion model provided a good fit to the redistribution of T. castaneum and T. confusum at all release densities, explaining an average of >60% of the variation in recaptures. For both species, mean displacement (directly proportional to the diffusion rate) exhibited a humped‐shaped relationship with conspecific density. Finally, we found that both species of beetle impacted the within‐patch movement rates of the other species, but the effect depended on density. For T. castaneum in the highest density treatment, the addition of equal numbers of T. castaneum or T. confusum had the same effect, with mean displacements reduced by approximately one half. The same result occurred for T. confusum released at an intermediate density. In both cases, it was total beetle abundance, not species identity that mattered to mean displacement. We suggest that displacement or diffusion rates that exhibit a nonlinear relationship with density or depend on the presence or abundance of interacting species should be considered when attempting to predict the spatial spread of populations or scaling up to heterogeneous landscapes. [ABSTRACT FROM AUTHOR]

In this study, we develop a conceptual bioeconomic model of floriculture production with aesthetic benefits, wherein optimal decision rules depend on an intertemporal economic objective to maximize profits subject to economic and biological processes. Necessary conditions of the model identify optimal trajectories (e.g., simultaneous, single, or cycling controls) that define decision rules and economic thresholds for profit maximizing growers producing crops with aesthetic attributes. The necessary conditions also highlight intertemporal trade-offs between aesthetic benefits and expected future net benefits of arthropod stocks, which have important policy implications. The model is applied to the greenhouse production system of ivy geranium. [ABSTRACT FROM AUTHOR]

Tomato spotted wilt orthotospovirus (TSWV) is one of the most successful pandemic agricultural pathogens transmitted by several species of thrips in a persistent propagative manner. Current management strategies for TSWV heavily rely on growing single-gene resistant cultivars of tomato ("Sw-5b" gene) and pepper ("Tsw" gene) deployed worldwide. However, the emergence of resistance- breaking strains (RB) in recent years has compounded the threat of TSWV to agricultural production worldwide. Despite this, an extensive study on the thrips transmission biology of RB strains is currently lacking. It is also unclear whether mutualistic TSWV-thrips interactions vary across different novel strains with disparate geographical origins. To address both critical questions, we studied whether and howfour novel RB strains of TSWV (two sympatric and two allopatric), along with a non-RB strain, impact western flower thrips (WFT) fitness and whether this leads to differences in TSWV incidence, symptom severity (virulence), and virus accumulation in two differentially resistant tomato cultivars. Our findings show that all RB strains increased WFT fitness by prolonging the adult period and increasing fecundity compared to non-RB and non-viruliferous controls, regardless of the geographical origin of strains or the TSWV titers in individual thrips, which were substantially low in allopatric strains. TSWV accumulation in thrips varied at different developmental stages and was unrelated to the infected tissues fromwhich thrips acquired the virus. However, it was significantly positively correlated to that in WFT-inoculated susceptible plants, but not the resistant ones. The TSW incidences were high in tomato plants infected with all RB strains, ranging from80% to 90% and 100% in resistant and susceptible plants, respectively. However, TSW incidence in the non-RB-infected susceptible tomato plants was 80%. Our findings provide new insights into how novel strains of TSWV, by selectively offering substantial fitness benefits to vectors, modulate transmission and gain a potential epidemiological advantage over non-RB strains. This study presents the first direct evidence of how vector-imposed selection pressure, besides the one imposed by resistant cultivars, may contribute to the worldwide emergence of RB strains. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Sciences, Belgrade is the property of University of Belgrade, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global food security is a critical challenge to fulfill the demands of an exponentially growing population. To date, growers rely on chemicals; the broad-spectrum application of synthetic molecules leads to environmental contamination, resistance development, residual toxicity, pest resurgence, and a detrimental eect on human health and cattle. Crop production needs to be improved considering environmental and human health concerns to ensure food security. Furthermore, economically important crops are prone to attack by insect pests, causing considerable yield losses. Microbes are an eco-friendly, versatile alternative, and a potential candidate for combatting destructive pests below the economic injury level and improving the plant’s health and productivity. Several microbial pathogens, including parasites, predators, parasitoids, pollinators, and many beneficial microorganisms, possess toxic properties against target organisms but do not cause harm to the non-target organisms. Entomopathogens (ENMs) have great potential for pest suppression due to their remarkable properties. Bacteria are host-specific, but fungi have a broader host range and can be significantly aected by both soil-dwelling and terrestrial insect pests. Virulent pathogens cause mortality in target insect pests known as ENMs and can penetrate through natural openings, ingestions, and integuments to cause a possible eect on target insect pests. The objective of using ENMs is to sustain productivity, improve environmental health, reduce pesticides, and conserve natural resources. Moreover, research is ongoing to discover other possible aspects, especially exploring potential ENMs. Therefore, there is a need for identification, isolation, and bioformulation to overcome the existing issues. This study is mainly focused on the status of bio-formulations, pathogenicity, their mode of action, and the potential application of dierent types of microbial formulations for sustainable pest management. [ABSTRACT FROM AUTHOR]

Phytoseiulus persimilis is a specialist predator of spider mites, with promising control effects. Its population generally has a stable sex ratio. Under appropriate conditions, the proportion of female offspring can reach 80%. But the mechanisms of sex determination in P. persimilis is still unclear. Sex-lethal (sxl) is an important gene in studying sex regulation mechanisms in insects. In the model organism Drosophila melanogaster, it has been proved to be a switch controlling sex determination. Herein, we screened one sex-lethal gene ortholog in the genome of P. persimilis (Ppsxl). We separated male and female offspring successfully based on the order of the egg laid, and found Ppsxl is expressed in both sexes at different stages. The expression peak was found in females 10 h after mating, and it was also highly expressed in eggs that developed into males. RNA interference was used to study the function of Ppsxl. When Ppsxl was interfered, all female individuals remained fertile. However, their cumulative fecundity decreased by 18.0%, daily fecundity decreased by 13.4%, and the proportion of female offspring decreased by 22.7%. This study showed that Ppsxl gene has a certain influence on the reproduction of P. persimilis, but its influence on sex determination may not be as critical as that in D. melanogaster. The regulation of sxl on P. persimilis was different from that in D. melanogaster. [ABSTRACT FROM AUTHOR]

Ongoing climate change may impact alpine plant populations via both direct effects of increased temperature and climate‐driven changes in interactions between plants and other organisms, such as insect herbivores. Rates of herbivory in high‐elevation environments are predicted to increase with warmer temperatures, which may also lead to changes in morphological and physiological traits that influence plant resistance. Yet, we currently know little about how temperature‐mediated changes in traits will impact alpine plant vulnerability to herbivores, as well as the extent to which populations from high‐elevation environments might need to rapidly adapt to increasing herbivore pressure with rising temperatures.We assessed the effect of experimental warming on the relative vulnerability of populations of the alpine plant Arabis alpina from different elevations to a specialist herbivore. Herbivore performance was measured on plants from nine populations grown in climate chambers at two temperatures, representing low (warm) and high (cold) elevations. We also measured changes in putative drivers of performance: plant phenological, chemical and defence traits. Assuming populations would be adapted to local climates and levels of herbivory, we predicted that low‐elevation populations would be more resistant to herbivores under warmer temperatures than high‐elevation populations.We found reduced performance of a specialist herbivore on A. alpina grown under warm rather than cold conditions, though this effect varied with elevation. Larvae grew faster on high‐elevation populations than low‐elevation populations when grown under warm temperatures, whereas similar growth rates were observed for plants grown under colder temperatures, consistent with plant adaptation to the lower existing herbivore pressure in cold, high‐elevation environments. Regression analyses suggested that polar metabolite variation explained more variance in larval performance than changes in defensive glucosinolates or morphological traits.Our results suggest that although physiological responses to warming may increase the resistance of cold‐adapted plants to herbivory, populations from different elevations may differ in their interactions with herbivores under climate warming. Without genetic adaptation, existing physiological responses of high‐elevation populations to warmer temperatures may leave these populations vulnerable to the increases in herbivore pressure predicted under climate change. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The Indian meal moth (Plodia interpunctella) is becoming an important biological model to study silk. While there are many potential applications to materials science and medicine, many aspects of silk production in this species remain unknown. Here we characterize the silk of P. interpunctella by measuring the width of larval wandering and pupal silk strands and find that the latter is significantly thicker than the former. We also report intraspecific variation in pupal silk production in our lab-reared colony with a very small number of individuals forgoing pupal silk production entirely (< 4%). Overcrowding had no effect on silk formation, but exposure to elevated temperature reduced pupal silk production. [ABSTRACT FROM AUTHOR]

The red imported fire ant (Solenopsis invicta) may disrupt biological control of hibiscus mealybug (Nipaecoccus viridis) in Florida citrus. Controlling S. invicta may therefore be necessary for effective management of hibiscus mealybug. We evaluated four different methods to control S. invicta (ground applications of insecticide, two different insecticidal ant baits and spot‐treating ant colonies with hot water) to determine how these different treatments affected ants tending to hibiscus mealybug colonies, natural enemy abundance within hibiscus mealybug colonies and hibiscus mealybug colony abundance. While all treatments reduced the number of S. invicta colonies in treated areas compared to an untreated control, only ground applications of insecticide and the two ant baits significantly reduced the abundance of S. invicta found tending hibiscus mealybug colonies. Additionally, significantly more Brachymyrmex obscurior ants were found tending mealybug colonies in plots treated with either of the two ant baits. There was no significant effect of treatment on the abundance of natural enemies in hibiscus mealybug colonies, but significantly fewer natural enemies were found in mealybug colonies tended by S. invicta, and significantly more natural enemies were found in mealybug colonies tended by B. obscurior. Ground applications of insecticide, the abamectin ant bait Clinch and hot water treatments all reduced the overall number of hibiscus mealybug colonies compared with control areas, while the S‐methoprene ant bait Extinguish did not. Our results suggest that reducing the number of S. invicta tending hibiscus mealybug colonies can lead to higher natural enemy abundance and lower hibiscus mealybug abundance. However, methods used to control S. invicta may have different impacts on ant species like B. obscurior, leading to different outcomes with natural enemies. [ABSTRACT FROM AUTHOR]

Hessian fly (HF) (Mayetiola destructor Say) is an obligate destructive pest of wheat (Triticum aestivum L.) causing severe economic losses worldwide. Deployment of resistant wheat cultivars harboring HF resistance (H) genes is still the most effective and economical method to manage this insect pest. However, extensive use of H genes can impose selection pressure on HF populations, leading to the development of virulent biotypes that can breakdown plant resistance. Further, increase in environmental temperatures to 25–30°C during the wheat‐growing season can also negatively impact HF resistance, thereby necessitating the identification of new and novel sources of HF resistance and evaluate them for temperature sensitivity. In the current study, we evaluated the phenotypic response of 254 Triticum turgidum (L.) wheat accessions of African origin to Biotype L HF infestation. Of these, 10 accessions exhibited >70% resistance to Biotype L HF infestation. These 10 resistant accessions also showed >70% resistance when screened with vH13 HF biotype. Additionally, these HF resistant lines were evaluated for expression of resistance at a higher temperature of 30°C, and three tetraploid wheat accessions that maintained 100% resistance to Biotype L HF at the increased temperature were identified. These newly identified HF resistant lines offer valuable tools to breeders and farmers that can be used in breeding programs to develop cultivars for durable resistance to HF and efficient crop management. Core Ideas: Triticum turgidum wheat accessions were phenotyped to identify new sources of resistance to Hessian fly. Identified 10 and 12 new sources of resistance in wheat to Biotype L and vH13 Hessian fly, respectively. Three of the tetraploid wheat lines maintain Hessian fly resistance at higher temperatures. [ABSTRACT FROM AUTHOR]

The nutritional quality of herbivorous insects' food can not only directly affect the herbivorous insects themselves, but can also indirectly affect their parasitoids. To investigate these cascading, multi-trophic effects, we reared cabbage looper, Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae), on artificial diets (8.1, 11.5, 16.75, 25.5, 34.25, and 43 g protein/liter diet) to assess how diet protein content affected the development of this common pest and its suitability as a host for the gregarious parasitoid, Cotesia vanessae (Reinhard) (Hymenoptera: Braconidae). Nonparasitized caterpillars experienced increased mortality when reared on 8.1 g protein/liter diet, and slower development and reduced pupal mass when reared on ≤16.75 g protein/liter diet. Host diet did not affect the percentage of hosts with parasitoid emergence nor the mass of individual parasitoids. However, parasitoid broods emerging from caterpillars reared on ≤25.5 g protein/liter diet were smaller and those reared on ≤16.75 g protein/liter diet exhibited prolonged development. The consequences of host diet on these latter F1 parasitoids did not affect their reproductive fitness. Caterpillars compensated for nutrient stress, induced by either low quality diet or parasitism, by increasing the amount of diet that they consumed. These collective results demonstrate the plasticity of host-parasitoid systems. Compensatory feeding allows the host caterpillar to moderate the consequences of low quality diets, which may subsequently affect the F1 parasitoids developing within the host, but not necessarily affect the F2 parasitoid generation. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Academic Journal of Biological Sciences. B, Zoology is the property of Egyptian Academic Journal of Biological Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Indian meal moth Plodia interpunctella Hubner (Pyralidae) is one of the most important pests of storage products in Iran, which is controlled by chemical fumigants. The use of plant essential oils and their compounds can be a suitable alternative to conventional fumigants due to their low risks to mammals. The present study invesrigates the mortality, inhibition of alpha-amylase enzyme, and the total protein content of Indian meal moth larvae (Plodia interpunctella (Hubner)) affected by saffron petal extract with high concentration of anthocyanin under experimental conditions. The concentrations have been 500, 690, 1000, 1380, and 2000 ppm, used against the fifth-instar larvae of the pest in four replications within 24 and 48 h. The lethal concentration to kill fifty percentage of larvae (LC50) by saffron petal extract after 24 and 48 hours is estimated to be 2244.950 and 1434.828 ppm, respectively. Alpha-amylase enzyme activity in the fifth instar larvae of Indian meal moth, treated by saffron petal extract, has been significantly different from the control. The highest activity of the alpha-amylase enzyme in pest larvae treated by saffron petal extract has been recorded with 83.1%, and the inhibitory rate of this enzyme has been 21.8%, which is significantly different from control. Also, the amount of protein in the larvae affected by this extract significantly differs from the control groups. Therefore, due to its fumigant toxicity and the alpha-amylase inhibitory activity of Indian meal moth larvae, saffron petal extract can be considered for additional researches on managing this pest based on an ecological principle. [ABSTRACT FROM AUTHOR]

The assessment of the long-term negative effects of acaricides on the target and non-target mites can help determine the toxicity and side effects of acaricides. The sublethal concentrations can be very precise and affect populations at concentrations lower than the conventional concentration and may supplement our knowledge about its sublethal effects on the physiology and behavior of insects/mites. Furthermore, we exposed the adults' biocontrol agents mite, Phytoseiulus persimilis Athias-Henriot and Neoseuilus californicus McGregor, to the LC10 and LC30 concentrations of the Cyflumetofen and then assayed the effects of these concentrations on the growth and development of the next generations under laboratory conditions. Analyzed data showed that sublethal concentrations of cyflumetofen significantly affected both species' biological parameters, including the total lifetime, fecundity, and longevity of the treated biocontrol agents compared with the control treatment. Due to our results, when P. persimilis and N. californicus adults were exposed to LC30 concentration of cyflumetofen, the length of the oviposition period of the treated P.persimilis and N. californicus were 20.34 and 19.66 days, respectively. At the same time, these values for the control-treated P. persimilis and N. californicus were 22.51 and 22.21, respectively. The intrinsic rate of increase (r) in control were 0.203 and 0.238, while those treated with LC10 and LC30 of cyflumetofen were estimated to be 0.238 and 0.214 for P. persimilis and 0.203 and 0.223 days–1, for N. californicus, respectively. Therefore, using sublethal concentrations of cyflumetofen is emphasized for designing integrated pest management programs and makes it possible to use biocontrol agents to control the spider mite; thus, it would benefit the farmers and consumers in the long run. [ABSTRACT FROM AUTHOR]

The effectiveness of predators in suppressing prey populations is known to be influenced by the predator-prey release ratio. The efficacy of Neoseiulus cucumeris (Oudemans) against Frankliniella occidentalis (Pergand) in the presence or absence of Tetranychus urticae Koch and Phytoseiulus persimilis Athias-Henriot on rose plants was evaluated in the present study. The decrease of F. occidentalis populations was compared at the six predator:prey ratios of 1:2, 1:5, 1:10, 1:20, 1:50, and 1:100 in the laboratory, and at the three release rates of 20, 40, and 100 predators per m2 in microcosm conditions. The plants without predators were considered as controls. All treatments with the release of N. cucumeris resulted in a significant decrease in F. occidentalis larval population compared to the control. The most suppression (84.5%) of F. occidentalis larvae was observed in the release rate of 100 adults of N. cucumeris per m2 in 30 days after the release of the predator. Predator ratios of 1:2 and 1:5 of N. cucumeris: F. occidentalis resulted in a 94.6 and 93.4% decrease in F. occidentalis larvae after 24 hours, respectively. The presence of T. urticae (as a competitor herbivore) and P. persimilis had no effect on the efficiency of N. cucumeris in the suppression of F. occidentalis. The dense webs of T. urticae decreased the efficiency of N. cucumeris at predator:prey ratios of 1:5 and 1:10 more than1:2. This study showed that the release of 100 adults of N. cucumeris per m2 would be sufficient to control F. occidentalis larvae on rose plants. Moreover, we demonstrated that higher release rates of N.cucumeris are needed when T. urticae's dense webs are present. [ABSTRACT FROM AUTHOR]

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