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Plant metabolism response to insect herbivores is the central theme of this publication. Genetically uniform individuals of European aspen (Populus tremula) were exposed to recurrent feeding by spongy moths (Lepidoptera) at specific time intervals. Changes in physiology, contents of phenolics and saccharides were quantified over the first hour. The unconventional experiment design, integrating analytical methods, and timeline led to the revealing of unexpected dynamics in plant metabolism. The time interval between herbivory initiation and sample collection revealed a pivotal moment, with induced defense activating strongly after 5  min of chewing resulting in an increase in catechin and procyanidin B1. After 10  min, a shift to a tolerant strategy occurs and induced substance concentrations return to control levels. Delayed physiological response was recorded as the first significant difference in transpiration between affected and nonaffected plants and was found after 10  min. A different strategy in exploitation of saccharides after spongy moths infestation was applied because the pool of selected saccharides was rising in the leaves but decreasing in the roots. Placing our results in the context of existing knowledge highlights the uncertain conceptual basis behind the often rigid and definitive classifications in induced plant defense or tolerance strategy. [ABSTRACT FROM AUTHOR]

Monochamus saltuarius Gebler (Coleoptera, Cerambycidae) serves as the primary carrier of Bursaphelenchus xylophilus (Steiner & Buhrer) (Aphelenchida, Aphelenchoididae) in the middle-temperate zone of China. Pine wilt disease caused by B. xylophilus leads to serious losses to pine forestry around the world. It is necessary to study the biological control of M. saltuarius to effectively prevent the further spread of B. xylophilus. To explore the insect resources that act as natural enemies of M. saltuarius, investigations were conducted on natural enemy insects by splitting Pinus koraiensis Siebold & Zucc (Pinales, Pinaceae) damaged by M. saltuarius and dissecting their trunks in Yingpan Village, Fushun County, Fushun City, Liaoning Province, China, in 2023. A larva of Inocellia (Amurinocellia) calida (H. Aspöck & U. Aspöck) (Raphidioptera, Inocelliidae) was discovered in the trunk of an infested P. koraiensis. Additionally, the feeding habits of I. calida were preliminarily examined under indoor conditions and a description of its morphological characteristics was provided. When placed in an indoor environment, the I. calida larva began pupating after a period of 21 days, during which time it consumed and attacked a total of 23 M. saltuarius larvae. Ultimately, after a pupal period of ten days, the I. calida larva emerged successfully as an adult. This discovery marks the first recorded presence of I. calida in Liaoning Province and the first documentation of I. calida in China, serving as a natural predatory enemy of M. saltuarius. [ABSTRACT FROM AUTHOR]

Mosquitoes, like other hematophagous insects, need to feed on blood to produce eggs. For laboratory colony maintenance, live animals are generally used, while various artificial feeders with different characteristics have been developed for experimental assays. In this study, a previously developed and pathogen-tested glass artificial feeder was selected and evaluated for rearing Aedes aegypti (Linnaeus). The device utilizes bovine gut as a membrane and human blood as a food source, maintaining a constant temperature of 37 °C through a thermostatic bath that enables water circulation around the feeder. Egg hatching, feeding rates, and fertility were analyzed for three cohorts of a parental lineage (P) and their respective filial lineages (F1) over a period of 4-5 weeks. The results demonstrated the efficacy of this methodology for rearing an Ae. aegypti colony up to the second generation, with average egg hatching rates of P= 0.92 and F1= 0.80, average feeding rates of P= 0.54 and F1= 0.73, and egg quantities obtained of P= 1809 and F1 = 8579. [ABSTRACT FROM AUTHOR]

The Melanoplinae Scotussa lemniscata (Stal), is considered a pest grasshopper of the Pampa region grasslands of Argentina. The goal of this study was to estimate the consumption rates of males and females S. lemniscata as fifth-instar nymphs and adults under controlled conditions (30°C, 14L:10D, 40% RH). The consumption trials were carried out using the perennial grass Festuca arundinacea (Schreber) (Poaceae) as food source. The study of these aspects is necessary to determine its current pest status more accurately. Consumption rates differed according to sex and stage of development. These where higher in the pre-reproductive adult stage vs. fifth-instar nymphs for both sexes. Additionally, adult females consumed significantly more (118.81 ± 9.41 mg/day) than the rest of individuals. The consumption of adult males and fifth-instar females was similar. Knowledge on consumption rates could contribute to the development of effective sustainable population management strategies. [ABSTRACT FROM AUTHOR]

Carabid beetles of the tribe Licinini use their asymmetric mandibles to open the shells of land snails. Prey handling of large snails has been described in a few Licinini species. We observed for the first time how a male of Licinus depressus (Paykull, 1790) opens the shells of small prey snails (Chondrina arcadica (Reinhardt, 1881)) and eats their soft bodies. The beetle holds the conical snail shell with its forelegs and breaks the wall of the right-hand coiled shell. In doing so, the beetle rotates the shell counter-clockwise opening it stepwise along the dorsal part of the whorls towards the apex. After some bites, the beetle interrupts the opening process and begins to feed on the snail's soft tissue. Then the beetle continues to break up the shell, shortly after which there is another feeding phase. The alternating sequence of shell breaking and feeding ends after 2 to 2.5 whorls when the beetle can no longer hold the prey's remaining intact shell. We compare this previously unknown way of prey handling with the reported predatory behaviour in large snails by other Licinini species. Our observations confirm the high plasticity of predatory behaviour in Licinini beetles. [ABSTRACT FROM AUTHOR]

Copyright of Harran Journal of Agricultural & Food Science is the property of Harran University, 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.)

Angarotipula is a small genus of Tipulidae with only fourteen described species in the world and seven known species in China. [ABSTRACT FROM AUTHOR]

Studies on the feeding behavior of hematophagous insects, particularly those of medical importance, are relevant for tracking possible pathogen transmission routes and identifying biases in the choice of vertebrates. We evaluated host selection of blood-feeding mosquitoes in a disturbed forest in the Magdalena Medio valley in Colombia from March 2017 to April 2018, after the introduction of Zika virus to the Americas from the 2015–2016 outbreak. We estimated vertebrate diversity and collected blood-engorged female mosquitoes. Genomic DNA/RNA was extracted from the mosquito's abdomen for vertebrate host identification and pathogen detection. We performed conventional PCR and sequencing, using universal primers targeting vertebrate regions of the eukaryotic mitochondrial genome to determine bloodmeal host. Additionally, we tested for the presence of flaviviruses in all mosquito samples with RT-PCR. Based on the identity and quantity of detected bloodmeals, we performed mosquito-vertebrate interaction network analysis and estimated topology metrics. In total, we collected 292 engorged female mosquitoes representing 20 different species. Bloodmeal analyses identified 26 vertebrate species, the majority of which were mammals (N = 16; 61.5%). No flaviviruses of medical importance were detected from the samples. Although feeding patterns varied, network analyses showed a high degree of specialization by mosquitoes and revealed ecological and phylogenetic relationships among the host community. We conclude that host selection or preference by mosquitoes is species specific. [ABSTRACT FROM AUTHOR]

Trehalose serves multifarious roles in growth and development of insects. In this study, we demonstrated that the high trehalose diet increased the glucose content, and high glucose diet increased the glucose content but decreased the trehalose content of Acyrthosiphon pisum. RNA interference (RNAi) of trehalose-6-phosphate synthase gene (ApTPS) decreased while RNAi of trehalase gene (ApTRE) increased the trehalose and glucose contents. In the electrical penetration graph experiment, RNAi of ApTPS increased the percentage of E2 waveform and decreased the percentage of F and G waveforms. The high trehalose and glucose diets increased the percentage of E2 waveform of A. pisum red biotype. The correlation between feeding behavior and sugar contents indicated that the percentage of E1 and E2 waveforms were increased but np, C, F and G waveforms were decreased in low trehalose and glucose contents. The percentage of np, E1 and E2 waveforms were reduced but C, F and G waveforms were elevated in high trehalose and glucose contents. The results suggest that the A. pisum with high trehalose and glucose contents spent less feeding time during non-probing phase and phloem feeding phase, but had an increased feeding time during probing phase, stylet work phase and xylem feeding phase. [ABSTRACT FROM AUTHOR]

The agricultural use of silica (SiO2) nanoparticles (NPs) has the potential to control insect pests while the safety and tritrophic effects on plants and beneficial natural enemies remains unknown. Here, we evaluate the effects of silica NPs on insect pests with different feeding niches, natural enemies, and a plant. Silica NPs were applied at different concentrations (75–425 mg/L) on field-cultivated faba bean and soybean for two growing seasons. The faba bean pests, the cowpea aphid Aphis craccivora and the American serpentine leafminer Liriomyza trifolii, and the soybean pest, the cotton leafworm Spodoptera littoralis, were monitored along with their associated predators. Additional laboratory experiments were performed to test the effects of silica NPs on the growth of faba bean seedlings and to determine whether the rove beetle Paederus fuscipes is attracted to cotton leafworm-infested soybean treated with silica NPs. In the field experiments, silica NPs reduced the populations of all three insect pests and their associated predators, including rove beetles, as the concentration of silica NPs increased. In soybean fields, however, the total number of predators initially increased after applying the lowest concentration. An olfactometer-based choice test found that rove beetles were more likely to move towards an herbivore-infested plant treated with silica NPs than to a water-treated control, suggesting that silica NPs enhance the attraction of natural enemies via herbivore-induced plant volatiles. In the laboratory, while silica NPs inhibited the development of faba bean roots at 400 mg/L, they did not affect germination percentage, germination time, shoot length, or vigor index compared to the control. [ABSTRACT FROM AUTHOR]

The wild silkworm (Cricula trifenistrata) reared under nutritional humidity and environmental stress condition to determine growth and dietary efficiency, compared with a control indicated that consumption of leaves is significantly influenced by humidity. [ABSTRACT FROM AUTHOR]

In bees from genus Melipona, differential feeding is not enough to fully explain female polyphenism. In these bees, there is a hypothesis that in addition to the environmental component (food), a genetic component is also involved in caste differentiation. This mechanism has not yet been fully elucidated and may involve epigenetic and metabolic regulation. Here, we verified that the genes encoding histone deacetylases HDAC1 and HDAC4 and histone acetyltransferase KAT2A were expressed at all stages of Melipona scutellaris, with fluctuations between developmental stages and castes. In larvae, the HDAC genes showed the same profile of Juvenile Hormone titers—previous reported—whereas the HAT gene exhibited the opposite profile. We also investigated the larvae and larval food metabolomes, but we did not identify the putative queen-fate inducing compounds, geraniol and 10-hydroxy-2E-decenoic acid (10HDA). Finally, we demonstrated that the histone deacetylase inhibitor 10HDA—the major lipid component of royal jelly and hence a putative regulator of honeybee caste differentiation—was unable to promote differentiation in queens in Melipona scutellaris. Our results suggest that epigenetic and hormonal regulations may act synergistically to drive caste differentiation in Melipona and that 10HDA is not a caste-differentiation factor in Melipona scutellaris. [ABSTRACT FROM AUTHOR]

The European crabapple Malus sylvestris, a crop wild relative of Malus domestica, is a major contributor to the cultivated apple genome and represents a potential source of interesting alleles or genes, particularly pest resistance traits. An original approach was used to explore the trophic interaction between M. sylvestris populations and its pest, the rosy apple aphid (Dysaphis plantaginea). Using 13 microsatellite markers, population genetic structure and level of crop-to-wild introgressions were inferred between M. sylvestris seedlings from three sites in Europe (Denmark, France, Romania), and M. domestica seedlings. Genetically characterized plants were also used to analyze aphid feeding behavior and fitness parameters. First, aphids submitted to two genetically close M. sylvestris populations (the Danish and French) exhibited similar behavioral parameters, suggesting similar patterns of resistance in these host plants. Second, the Romanian M. sylvestris population was most closely genetically related to M. domestica. Although the two plant genetic backgrounds were significantly differentiated, they showed comparable levels of sensitivity to D. plantaginea infestation. Third, aphid fitness parameters were not significantly impacted by the host plant's genetic background. Finally, crop-to-wild introgression seemed to significantly drive resistance to D. plantaginea independent of host plant population genetic structure, with hybrids being less suitable hosts. [ABSTRACT FROM AUTHOR]

Reproductive fitness and survival are enhanced by adaptive behaviors that are modulated by internal physiological states and external social contexts. The common bed bug, Cimex lectularius, is an obligate hematophagous ectoparasite that requires host blood for growth, development, and reproduction. We investigated how mating, starvation and social interactions affect host-seeking, blood feeding, oviposition, and survival of female bed bugs. The percentage of females that fed and the amount of blood they ingested were greater in mated females (90–100%) than in unmated females (48–60%). Mating state also modulated the female's orientation towards human skin odor in an olfactometer; more mated (69%) than unmated (23%) females responded to human odors. The response rate of unmated females (60%) to skin odor increased with longer starvation period, while the opposite pattern was observed in mated females (20%). Although fecundity after a single blood meal was unaffected by long or short residence and interaction with males, females subjected to frequent copulation attempts had lower survivorship and lifespan than females housed with males for only 24 h. Taken together, these results indicate that by adaptively and coordinately expressing behaviors based on the internal physiological state, females maximize their survival and reproductive fitness. [ABSTRACT FROM AUTHOR]

The feeding behavior of the giant ambush-predator "Bobbit worm" (Eunice aphroditois) is spectacular. They hide in their burrows until they explode upwards grabbing unsuspecting prey with a snap of their powerful jaws. The still living prey are then pulled into the sediment for consumption. Although predatory polychaetes have existed since the early Paleozoic, their bodies comprise mainly soft tissue, resulting in a very incomplete fossil record, and virtually nothing is known about their burrows and behavior beneath the seafloor. Here we use morphological, sedimentological, and geochemical data from Miocene strata in northeast Taiwan to erect a new ichnogenus, Pennichnus. This trace fossil consists of an up to 2 m long, 2–3 cm in diameter, L-shaped burrow with distinct feather-like structures around the upper shaft. A comparison of Pennichnus to biological analogs strongly suggests that this new ichnogenus is associated with ambush-predatory worms that lived about 20 million years ago. [ABSTRACT FROM AUTHOR]

Demodex is a genus of microscopic mites that live on human hosts, feeding on sebum and dead skin. They are classified as arachnids with an elongated abdomen that allows them to dwell in pores and hair follicles. The mites do not commonly cause any problems but a diseased state may arise if their population suddenly increases, leading to rosacea, blepharitis, and general dermatitis. Collecting the mites can be difficult and two collection methods were compared. The first method was spreading super glue onto a microscope slide and adhering it to the forehead for five minutes. The second was done by scraping the area on the forehead and transferring the debris onto another slide. For the eight participants, only one Demodex was found overall, using the super glue method. Our study concluded that, although mostly ineffective, the super glue method was best to collect and observe Demodex from human skin. [ABSTRACT FROM AUTHOR]

Invasive insect pests are known to cause yield loss and economic damage to grain sorghum crops (Sorghum bicolor). This damage can be exacerbated by invasive insect mutualisms, or beneficial interactions. For example, tawny crazy ants (Nylanderia fulva) (Hymenoptera:Formicidae) (TCA) tend sugarcane aphids (Melanaphis sacchari) (Hemiptera:Aphididae) (SCA) for the honeydew or sugary excretion that they produce from feeding on the plant. This tending can reduce plant nutrients, which decreases plant health. Currently, it has not been studied whether the mutualism between TCA and SCA has any effects on grain sorghum health. To access potential plant health effects of this mutualism, potted grain sorghum plants of similar development were evaluated in a greenhouse environment. Plants were evaluated in pairs, with each individual plant having 25 sexually mature SCA and the treatment plants having an addition of 300 TCA workers. Plants were enclosed in individual fine mesh cages and placed inside a Fluon lined bin to prevent the organisms from escaping. Damage was assessed by measuring the dry root weight, change in leaf chlorosis, and change in plant stem diameter after the 14-day experiment. There were no statistically significant differences found in the treatments for dry root weight (P = 0.61), leaf chlorosis (P = 0.37) or stem growth (P = 0.25). Future studies should increase the duration of the experiment to determine potential effects of long-term interactions of TCA and SCA on grain sorghum health. Monitoring and controlling ant-aphid mutualisms may be important for the Integrated Pest Management for this agricultural crop. [ABSTRACT FROM AUTHOR]

Efforts to control and dispose of human food waste typically rely upon increasing public awareness of the problem and improving retail management practices to mitigate the amount of food thrown away. Food waste becomes an increasingly noticeable problem as the world population continues to grow, creating a host of environmental concerns. A recently executed experiment examined the ability of Hermetia illucens (Family Stratiomyidae and Order Diptera) to decompose household food waste. In previous studies, Hermetia illucens (Black Soldier Fly) has shown promising ability to decompose organic food waste. In our experiment, we intervened in the life cycles of Hermetia illucens larvae by feeding them five separate food groups over a two week timespan: grains, vegetables, fruits, meat, and dairy. By comparing the initial start weight of the larvae and the end weight after the larvae consumed their respective food groups, it was determined that Hermetia illucens larvae decompose fruit, meat, and vegetables most effectively. These findings suggest that Hermetia illucens larvae may be a viable alternative to decompose specific food groups in everyday household environments. [ABSTRACT FROM AUTHOR]

There are certain morphological features and individual characteristics that are special to varying species that affect their lifecycle through every phase. Certainly, not every species will live for the same amount of time from emergence to death. In our case, there are two species of interest for our experiment. These two species are Chrysomya rufifacies (Diptera: Calliphoridae) (Macquart) and Cochliomyia macellaria (Diptera: Calliphoridae) (Fabricus). Both fly species have a detrimental impact on the livestock industry. They enjoy feeding on dead tissue after a sustained injury and are the cause of myiasis presence in several livestock species. For this reason, and many more, they are a concern economically. Through general observations, we have noticed that adult Chrysomya rufifacies appear to be much bigger than Cochliomyia macellaria adults are, and wondered if this meant there would be a distinction in longevity of adult life and if the variation in size is indicative of adulthood longevity. Wild maggots were obtained and raised on foodgrade bovine liver. The adults were given a sugar water mixture daily until death, in which the number of days lived by each adult was recorded. The data was analyzed using a T-test in SPSS. Analyzing the data this way allowed us to obtain and compare measurements of mean, standard deviation, standard error, and the P value. Our results indicate that Cochliomyia macellaria (p=.0467) adults live much longer than Chrysomya rufifacies adults do, and that size is not indicative of longer life. Further research is needed to evaluate varying results for these two species, as well as conduct new experiments with other forensically important insect species. [ABSTRACT FROM AUTHOR]

The aim of the present study is to investigate the effect of Baikal EM1 on the productive parameters of the bee colonies (Apis mellifera L.) during spring and autumn feeding and the chemical composition of the worker bee bodies. Two groups of bee colonies were formed (1 experimental group and 1 control group). During the spring feeding the experimental group was fed with Baikal -1 at a dose of 5 ml/0.500 L added in the sugar syrup (sugar:water 1:1) for 4 consecutive days at the start of the experiment. Each bee colony received 5 L sugar syrup. During the autumn feeding the experimental group received Baikal -1 at a dose of 20 ml/10 L sugar syrup. Each bee colony received 10 L sugar syrup. The control group received only sugar syrup. The spring and autumn feeding of the group fed with Baikal EM1 significantly increases the strength of the bee colonies and the amount of the sealed worker brood compared to the control group. According to the results obtained for the strength of the bee colonies and the bee brood supplementary feeding with Baikal EM1 is very effective in the autumn feeding. For these two parameters there are significant differences between the experimental and control on 29.08. (p<0.01), 10.09. (p<0.05) and 22.09.2018 (p<0.01). Statistically significant differences were reported for the strength of the bee colonies (p<0.01) and the amount of sealed worker brood (p<0.001) in the experimental group receiving Baikal EM1 before wintering compared to the control group. It can be expected to reveal a tendency for better spring development in the next year. Feeding with Baikal EM1 does not affect the chemical composition of worker bee bodies. [ABSTRACT FROM AUTHOR]

Results of studying the biology of the East Asian seed beetle, Megabruchidius dorsalis (Fåhreus, 1839) (Chrysomelidae, Bruchinae), in the laboratory and field conditions of Kharkiv Region are presented. Mainly the fourth instar larvae and adult beetles hibernate in beans on the soil, in beans on trees and in shelters. Overwintered beetles appear in the first decade of May and do not need maturation feeding. The beans of honey locust (Gleditsia triacanthos L.) are an important factor in stimulating the start of oviposition. The beetles start oviposition only 8-11 days after emergence if only the seeds are proposed as a substrate, but if the beans are present, the beetles begin to mate and lay eggs in two days. Fertility of females in the laboratory is 110 ± 40 eggs. Egg mortality under natural conditions is 50-93%. Megabruchidius dorsalis did not colonize the seeds of chickpeas (Cicer arietinum L.) and lentils (Lens culinaris Medik.). The beetle inhabited 10- 40% of seeds of vigna (Vigna sesquipedalis Fruw) and common beans (Phaseolus vulgaris L.), but the 1st instar larvae died. Beetles feed on the seeds of Gleditsia of past years both in their natural habitat and in the Kharkiv Region for most of the growing season. Only in the second half of August they inhabit the seeds of the current year's crop. In the Kharkiv Region, M. dorsalis has three generations per year like in its native range in Sagamihara (Japan). The development duration of one generation in the laboratory is 37 days at 27 ºC and 41 days at 25 ºC. [ABSTRACT FROM AUTHOR]

Copyright of Bioscience Journal is the property of Bioscience Journal 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.)

Jasmonate synthesis and signalling are essential for plant defense upregulation upon herbivore or microbial attacks. Stress‐induced accumulation of jasmonoyl‐isoleucine (JA‐Ile), the bioactive hormonal form triggering transcriptional changes, is dynamic and transient because of the existence of potent removal mechanisms. Two JA‐Ile turnover pathways operate in Arabidopsis, consisting in cytochrome P450 (CYP94)‐mediated oxidation and deconjugation by the amidohydrolases IAR3/ILL6. Understanding their impacts was previously blurred by gene redundancy and compensation mechanisms. Here we address the consequences of blocking these pathways on jasmonate homeostasis and defenses in double‐2ah, triple‐3cyp mutants, and a quintuple‐5ko line deficient in all known JA‐Ile‐degrading activities. These lines reacted differently to either mechanical wounding/insect attack or fungal infection. Both pathways contributed additively to JA‐Ile removal upon wounding, but their impairement had opposite impacts on insect larvae feeding. By contrast, only the ah pathway was essential for JA‐Ile turnover upon infection by Botrytis, yet only 3cyp was more fungus‐resistant. Despite building‐up extreme JA‐Ile levels, 5ko displayed near‐wild‐type resistance in both bioassays. Molecular analysis indicated that restrained JA‐Ile catabolism resulted in enhanced defense/resistance only when genes encoding negative regulators were not simultaneously overstimulated. This occurred in discrete stress‐ and pathway‐specific combinations, providing a framework for future defense‐enhancing strategies. We investigated the impacts of impairing catabolic pathways of the defense hormone jasmonoyl‐isoleucine in higher order mutants of Arabidopsis thaliana. The data disclosed pathway‐specific changes on resistance to herbivory or fungal infection that correlated with feedback inhibition responses. [ABSTRACT FROM AUTHOR]

Malus sieversii is the wild progenitor for many cultivars of domesticated apple and an important germplasm resource for breeding. However, this valuable species faces a significant threat in the areas north of the Tianshan Mountains in China, by the invasion of Agrilus mali, a destructive pest of apple trees belonging to the family Buprestidae. Our preliminary study has has shown that there may be resistance to this insect in M. sieversii plants in the field, but the corresponding molecular mechanisms remain unclear. In this study, we compared the response of insect-resistant and insect-susceptible plants of M. sieversii to insect feeding using full-length transcriptome and targeted metabolome. 112,103 non-chimeric full-length reads (FLNC) totaling 10.52 Gb of data were generating with Pacific Biosciences SingleMolecule, Real-Time (PacBio SMRT) sequencing. A total of 130.06 Gb data of long reads were acquired with an Illumina HiSeq. Function annotation indicated that the different expressed genes (DEGs) were mainly involved in signal transduction pathway of plant hormones and in the synthesis of compounds such as terpenes, quinones, flavonoids, and jasmonic acid. Through targeted metabolome analysis resistant strains showed higher levels of trans-cinnamic acid, caffeine and ferulic acid after pest infestation. This study helps to decipher the transcriptional changes and related signaling paths in M. sieversii after an insect feeding, which lays a foundation for further research on molecular mechanisms of insect resistance in apples. [ABSTRACT FROM AUTHOR]

Insect effectors are mainly secreted by salivary glands, modulate plant physiology and favor the establishment and transmission of pathogens. Feeding is the principal vehicle of transmission of Candidatus Liberibacter asiaticus (Ca. Las) by the Asian citrus psyllid (ACP), Diaphorina citri. This study aimed to predict putative ACP effectors that may act on the Huanglongbing (HLB) pathosystem. Bioinformatics analysis led to the identification of 131 candidate effectors. Gene expression investigations were performed to select genes that were overexpressed in the ACP head and modulated by Ca. Las. To evaluate the actions of candidate effectors on D. citri feeding, six effectors were selected for gene silencing bioassays. Double-stranded RNAs (dsRNAs) of the target genes were delivered to D. citri adults via artificial diets for five days. RNAi silencing caused a reduction in the ACP lifespan and decreased the salivary sheath size and honeydew production. Moreover, after dsRNA delivery of the target genes using artificial diet, the feeding behaviors of the insects were evaluated on young leaves from citrus seedlings. These analyses proved that knockdown of D. citri effectors also interfered with ACP feeding abilities in planta, causing a decrease in honeydew production and reducing ACP survival. Electrical penetration graph (EPG) analysis confirmed the actions of the effectors on D. citri feeding behaviors. These results indicate that gene silencing of D. citri effectors may cause changes in D. citri feeding behaviors and could potentially be used for ACP control. [ABSTRACT FROM AUTHOR]

Silicon (Si) supplementation is well-known for enhancing plant resistance to insect pests, however, only recently studies revealed that Si accumulation in the plant not only confers a mechanical barrier to insect feeding, but also primes jasmonic acid-dependent defenses. Here, we examined whether Si supplementation alters wheat volatile emissions that influence the bird cherry-oat aphid (Rhopalosiphum padi) olfactory preference and the aphid parasitoid Lysiphlebus testaceipes. Even though Si accumulation in wheat did not impact aphid performance, we found that R. padi preferred constitutive volatiles from–Si wheat over those emitted by +Si wheat plants. In Y-tube olfactometer bioassays, the parasitoid was attracted to volatiles from +Si uninfested wheat, but not to those from–Si uninfested wheat. +Si and–Si aphid-infested plants released equally attractive blends to the aphid parasitoid; however, wasps were unable to distinguish +Si uninfested plant odors from those of aphid-infested treatments. GC-MS analyses revealed that +Si uninfested wheat plants emitted increased amounts of a single compound, geranyl acetone, compared to -Si uninfested wheat, but similar to those emitted by aphid-infested treatments. By contrast, Si supplementation in wheat did not alter composition of aphid-induced plant volatiles. Our results show that changes in wheat volatile blend induced by Si accumulation mediate the non-preference behavior of the bird cherry-oat aphid and the attraction of its parasitoid L. testaceipes. Conversely to the literature, Si supplementation by itself seems to work as an elicitor of induced defenses in wheat, and not as a priming agent. [ABSTRACT FROM AUTHOR]

Copyright of Arab Journal of Plant Protection is the property of Arab Society for Plant Protection 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.)

Lumpy skin disease (LSD) is among a number of vector-borne diseases (VBDs) threatening the Balkans and therefore, preventing feeding of insects on cattle would reduce the spread of VBDs. In order to test the efficiency of Livestock Protective Fences (LPF) in the protection of dairy cattle from insect bites, a case-control study was conducted, in the districts of Nišava, Pirot and Pčinja, Southern Serbia. It consisted in comparing the number of biting flies collected within time, between 10 farms protected with LPF and 10 non protected ones. The insects were collected using two types of traps; the monoconical Vavoua trap set outside in between forested areas or rivers and the actual farm, and the BGsentinel trap baited with CO2, placed in proximity of the cattle but outside the stable. Vectors were collected every 15 days for 48 hours from May to October 2018 and kept in vials containing 70% of ethanol. Catches per trap were separately stored and for each trap, insects were classified according to species and sex and then counted. Data on milk parameters were analyzed separately, on data collected within protected farms, before and after the LPF deployment, and on data without protection at all. It was not possible to detect a direct impact of LPF on vector densities but the number of bacteria colonies (CFU) values were reduced. Some corrections/adaption in the methodology used may lead to better impact. [ABSTRACT FROM AUTHOR]

Philaenus spumarius (Meadow Spittlebug, Homoptera: Cercopoidea) is a cosmopolitan generalist insect that feeds on a wide repertoire of host plants in the field. We studied density and growth of Meadow Spittlebugs on a range of host plants on Kent Island, a boreal island in the Bay of Fundy, NB, Canada. The highest spittlebug densities were on Cirsium arvense (Canadian Thistle), although spittlebugs had larger body sizes on Solidago rugosa (Rough-stemmed Goldenrod) and Anaphalis margaritacea (Pearly Everlasting). We fertilized plots of Rough-stemmed Goldenrod in the field over 3 weeks to examine the effects of plant quality on development of Meadow Spittlebugs. Following fertilization, there were fewer nymphs present in fertilized plots than in unfertilized plots, indicating faster nymph maturation to adulthood on fertilized plants. This study offers an initial report of the host plants used by Meadow Spittlebugs in northeastern boreal habitat, variation in density and performance of the species on a range of host plants, and the effects of plant fertilization on spittlebug life history. [ABSTRACT FROM AUTHOR]

Transporters play an important role in the uptake and redistribution of agrochemicals to the site of insect feeding. The product of the Arabidopsis thaliana gene AtAAP1 substantially contributes to inorganic nitrogen acquisition under ecologically relevant amino acid concentrations. Here, the transporter ability of AtAAP1 to a chlorantraniliprole-alanine conjugate (CAP-Ala-1) was tested both in planta and in vitro. Thirty-day-old and 15-day-old plants overexpressing AtAAP1 increased the uptake of CAP-Ala-1 into the roots, whereas AtAAP1 deficiency did not completely block the uptake of CAP-Ala-1. An uptake experiment carried out in Xenopus laevis oocytes expressing AtAAP1 showed that CAP-Ala-1 interacted with AtAAP1. Although little native AtAAP1 transcription was present in the leaves, constitutive expression of AtAAP1 in plants significantly increased the ability of the leaf mesophyll protoplasts to take up CAP-Ala-1. The observations supported the possibility of exploiting AtAAP1 as a component of a novel delivery and redistribution system for amino acid-based pesticide conjugates. [ABSTRACT FROM AUTHOR]

Due to a lack of Mesozoic fossil records, the origins and early evolution of feather-feeding behaviors by insects are obscure. Here, we report ten nymph specimens of a new lineage of insect, Mesophthirus engeli gen et. sp. nov. within Mesophthiridae fam. nov. from the mid-Cretaceous (ca. 100 Mya) Myanmar (Burmese) amber. This new insect clade shows a series of ectoparasitic morphological characters such as tiny wingless body, head with strong chewing mouthparts, robust and short antennae having long setae, legs with only one single tarsal claw associated with two additional long setae, etc. Most significantly, these insects are preserved with partially damaged dinosaur feathers, the damage of which was probably made by these insects' integument-feeding behaviors. This finding demonstrates that feather-feeding behaviors of insects originated at least in mid-Cretaceous, accompanying the radiation of feathered dinosaurs including early birds. Numerous feathered dinosaurs and early birds have been discovered from the Jurassic and Cretaceous, but the early evolution of feather-feeding insects is not clear. Here, Gao et al. describe a new family of ectoparasitic insects from 10 specimens found associated with feathers in mid-Cretaceous amber. [ABSTRACT FROM AUTHOR]

Background: Phloem-feeding insects are known to modulate the salicylic acid (SA) signaling pathway in various plant-insect interaction models. Diaphorina citri is a phloem feeding vector of the deadly phytopathogens, Candidatus Liberibacter americanus and Candidatus Liberibacter asiaticus, and the interactions of D. citri with its host that may modulate plant defenses are not well understood. The objectives of this study were to investigate the molecular mechanisms involved in transcriptional regulation of SA modification and activation of defense-associated responses in sweet orange (Citrus sinensis) exposed to various durations (7-, 14- and 150- days) of continuous feeding by D. citri. Results: We quantified expression of genes involved in SA pathway activation and subsequent modification, as well as, associated SA metabolites (SA methyl ester, 2,3-DHBA, and SA 2-O-β-D-glucoside). NPR1 and PR-1 expression was upregulated in plants exposed to continuous feeding by D. citri for 14 days. Expression of BSMT-like, MES1-like and DMR6-like oxygenase, as well as, accumulation of their respective SA metabolites (SA methyl ester, 2,3-DHBA) was significantly higher in plants exposed to continuous feeding by D. citri for 150 days than in those without D. citri infestation. Concomitantly, expression of UGT74F2-like was significantly downregulated and its metabolite, SA 2-β-D-glucoside, was highly accumulated in trees exposed to 150 d of feeding compared to control trees without D. citri. Conclusions: D. citri herbivory differentially regulated transcription and SA-metabolite accumulation in citrus leaves, depending on duration of insect feeding. Our results suggest that prolonged and uninterrupted exposure (150 d) of citrus to D. citri feeding suppressed plant immunity and inhibited growth, which may highlight the importance of vector suppression as part of huanglongbing (HLB) management in citrus. [ABSTRACT FROM AUTHOR]

Yeasts form mutualistic interactions with insects. Hallmarks of this interaction include provision of essential nutrients, while insects facilitate yeast dispersal and growth on plant substrates. A phylogenetically ancient chemical dialogue coordinates this interaction, where the vocabulary, the volatile chemicals that mediate the insect response, remains largely unknown. Here, we used gas chromatography-mass spectrometry, followed by hierarchical cluster and orthogonal partial least-squares discriminant analyses, to profile the volatomes of six Metschnikowia spp., Cryptococcus nemorosus, and brewer's yeast (Saccharomyces cerevisiae). The yeasts, which are all found in association with insects feeding on foliage or fruit, emit characteristic, species-specific volatile blends that reflect the phylogenetic context. Species specificity of these volatome profiles aligned with differential feeding of cotton leafworm (Spodoptera littoralis) larvae on these yeasts. Bioactivity correlates with yeast ecology; phylloplane species elicited a stronger response than fruit yeasts, and larval discrimination may provide a mechanism for establishment of insect-yeast associations. The yeast volatomes contained a suite of insect attractants known from plant and especially floral headspace, including (Z)- hexenyl acetate, ethyl (2E,4Z)-deca-2,4-dienoate (pear ester), (3E)-4,8-dimethylnona-1,3,7- triene (DMNT), linalool, β-terpineol, -myrcene, or (E,E)-β-farnesene. A wide overlap of yeast and plant volatiles, notably floral scents, further emphasizes the prominent role of yeasts in plant-microbe-insect relationships, including pollination. The knowledge of insect-yeast interactions can be readily brought to practical application, as live yeasts or yeast metabolites mediating insect attraction provide an ample toolbox for the development of sustainable insect management. [ABSTRACT FROM AUTHOR]

Summary: Extracellular DNA, released by damaged plant cells, acts as a damage‐associated molecular pattern (DAMP). We demonstrated previously that the small brown planthopper (Laodelphax striatellus, SBPH) secreted DNase II when feeding on artificial diets. However, the function of DNase II in insect feeding remained elusive.The influences of DNase II on SBPHs and rice plants were investigated by suppressing expression of DNase II or by application of heterogeneously expressed DNase II.We demonstrated that DNase II is mainly expressed in the salivary gland and is responsible for DNA‐degrading activity of saliva. Knocking down the expression of DNase II resulted in decreased performance of SBPH reared on rice plants. The dsDNase II‐treated SBPH did not influenced jasmonic acid (JA), salicylic acid (SA), ethylene (ET) pathways, but elicited a higher level of H2O2 and callose accumulation. Application of heterogeneously expressed DNase II in DNase II‐deficient saliva slightly reduced the wound‐induced defence response.We propose a DNase II‐based invading model for SBPH feeding on host plants, and provide a potential target for pest management. [ABSTRACT FROM AUTHOR]

The article offers information on the proboscis butterfly feeding. It mentions proboscis is formed by the stitching together of two strap-like structures, ‘galea', which are extensions of the maxillae; and also mentions that being liquid feeders, they have dispensed with the mandibles, a fourth pair of mouthparts between the labrum and maxillae, which are present in many other insects that chew solid food.

The article focuses on an identification service for insects and invertebrates is managing peoples' expectations including for invertebrates such as spiders, there is a definite fear factor that comes with the majority of the enquiries; for insects like butterflies and moths it is often an interest coming from a positive angle; and the maggot is an ingenious feeding machine covered in hooks.

Including drought-tolerant crops, such as quinoa (Chenopodium quinoa Willd.), in rotation could benefit growers facing increased water shortages in the western United States. Yet, there are limited varieties available and varietal response to irrigation rate has not been described. To address this, a line-source irrigation trial was conducted with quinoa from commercially available sources and the breeding program at Washington State University. No seed was produced regardless of irrigation rate in either year or field location possibly because of high summer temperatures (pollen sterility or seed abortion) or seed damage from insect feeding (i.e. Lygus hesperus). A minimum of 23 to 42 cm total irrigation was required to produce maximum biomass in 2013. The impact of irrigation rate in 2014 was minimal because of high rainfall. Early season rainfall may be sufficient for quinoa production in this region; however, lack of seed set remains a critical limiting factor. [ABSTRACT FROM AUTHOR]

Holometabolous insects stop feeding at the final larval instar stage and then undergo metamorphosis; however, the mechanism is unclear. In the present study, using the serious lepidopteran agricultural pest Helicoverpa armigera as a model, we revealed that 20-hydroxyecdysone (20E) binds to the dopamine receptor (DopEcR), a G protein-coupled receptor, to stop larval feeding and promote pupation. DopEcR was expressed in various tissues and its level increased during metamorphic molting under 20E regulation. The 20E titer was low during larval feeding stages and high during wandering stages. By contrast, the dopamine (DA) titer was high during larval feeding stages and low during the wandering stages. Injection of 20E or blocking dopamine receptors using the inhibitor flupentixol decreased larval food consumption and body weight. Knockdown of DopEcR repressed larval feeding, growth, and pupation. 20E, via DopEcR, promoted apoptosis; and DA, via DopEcR, induced cell proliferation. 20E opposed DA function by repressing DA-induced cell proliferation and AKT phosphorylation. 20E, via DopEcR, induced gene expression and a rapid increase in intracellular calcium ions and cAMP. 20E induced the interaction of DopEcR with G proteins αs and αq. 20E, via DopEcR, induced protein phosphorylation and binding of the EcRB1-USP1 transcription complex to the ecdysone response element. DopEcR could bind 20E inside the cell membrane or after being isolated from the cell membrane. Mutation of DopEcR decreased 20E binding levels and related cellular responses. 20E competed with DA to bind to DopEcR. The results of the present study suggested that 20E, via binding to DopEcR, arrests larval feeding and promotes pupation. [ABSTRACT FROM AUTHOR]

Previous studies have shown a causal link between mammalian herbivory, tolerance, and chemical defense in Arabidopsis thaliana, driven by the process of endoreduplication (replication of the genome without mitosis). Removal of the apical meristem by mammalian herbivores lowers auxin, which triggers entry into the endocycle. Increasing chromosome number through endoreduplication, and therefore gene copy number, provides a means of increasing gene expression promoting rapid regrowth rates, higher defensive chemistry and enhanced fitness. Here, we assess whether insect leaf-feeding elicits the same compensatory response as the removal of apical dominance. Insect feeding has been shown to downregulate auxin production, which should trigger endoreduplication. Results here support this contention; insect leaf-feeding by Trichoplusia ni elicited a compensatory response similar to that of mammalian herbivores—an ecotype-specific response consistent with the level of endoreduplication. The interactive effects of mammalian and insect herbivory were also assessed to determine whether interactions were additive (pairwise) or non-additive (diffuse) on tolerance (fitness). Specifically, results indicate that herbivory is either diffuse (a significant clipping × T. ni interaction) or pairwise (no significant interaction between clipping and T. ni herbivory), dependent upon plant genotype and compensatory ability. In general, herbivore-induced changes in plant quality appear to be responsible for the observed differences in herbivory and fitness compensation. We discuss the importance of evaluating endoreduplication among plants within a population to avoid masking the association between tolerance and resistance and the fitness consequences of multi-herbivore interactions. [ABSTRACT FROM AUTHOR]

In the present study we investigated the diet of Eleonora's falcons in Greece and assessed the regional dietary pattern of 16 breeding colonies of the Aegean. Overall 224 nests were visited and a total of 8067 prey items were collected which contained two mollusca classes, seven insect orders, one reptile family, two mammalian taxa and at least 54 avian species. Cicadas were the most common insects found in pellets (45.1%) followed by flying ants (34.8%) and beetles (15.8%) while just 20 species (33.3%) accounted for over 90% of the avian prey items identified in bird remains dominated (>50%) by the Willow Warbler (Phylloscopus trochilus), the Red-backed Shrike (Lanius collurio) and the Whitethroat (Sylvia communis). Insect feeding peaked in late August (39.8%) and late September (20.8%), whereas bird remains built up in falcon nests from mid-August onwards, culminating in late September (57.2%) and declined abruptly afterwards. Overall the falcons' diet diversity increased as the breeding season progressed and from the north towards the south Aegean. The avian prey species richness was negatively influenced by the distance of the colonies from the mainland and the weather conditions during September which coincides with the fledgling period of the young and the autumn peak of passerine migration. [ABSTRACT FROM AUTHOR]

An individual-based model is presented which shows that cyclic insects outbreaks in the forest (here presented as a certain type of the dynamics of total numbers of insects in the forest) can be a result of the joint action of four factors: (1) spatial structure of the system — resources, green tree biomass, used by larval insects are distributed in a two-dimensional space, (2) properties of trees — their limited resistance to feeding by insects, and regeneration ability after some time of relaxation, when they cannot sustain a local insect population, (3) insect properties — the most important of which is the ability of adult individuals to move between spatially distributed resources and to lay eggs on neighbouring trees, and (4) the type of dynamics of local insect population exploiting resources of a tree, which depends on individual variability of insects and their progeny production. Insects disperse from the original tree and occupy successive not infested trees over the forest, omitting the trees with exploited resources that need time for regeneration. The cyclic outbreak dynamics will take place when insects have opportunity to return to the places where there are trees with regenerated resources. In addition to the cyclic outbreak, we will observe permanent outbreaks (small fluctuations of insect, combined with a similar dynamics of tree biomass) or pulse outbreaks (an increase in the number of insects, followed by their extinction and leading to a temporary destruction of tree biomass). The type of the simulation output will depend on the values of the model parameters. Intermediate resistance of trees to insect feeding and their not very short regeneration time will lead to cyclic outbreaks. Additionally great number of dispersing insects will promote cyclic outbreaks. High degree of individual variability, high mortality of adult insects or small progeny production will produce favourable conditions for permanent outbreaks. Pulse outbreaks can easily occur when insect individual variability is small or progeny production is high. [ABSTRACT FROM AUTHOR]

Insects have evolved effectors to conquer plant defense. Most known insect effectors are isolated from sucking insects, and examples from chewing insects are limited. Moreover, the targets of insect effectors in host plants remain unknown. Here, we address a chewing insect effector and its working mechanism. Cotton bollworm (Helicoverpa armigera) is a lepidopteran insect widely existing in nature and severely affecting crop productivity. We isolated an effector named HARP1 from H. armigera oral secretion (OS). HARP1 was released from larvae to plant leaves during feeding and entered into the plant cells through wounding sites. Expression of HARP1 in Arabidopsis mitigated the global expression of wounding and jasmonate (JA) responsive genes and rendered the plants more susceptible to insect feeding. HARP1 directly interacted with JASMONATE-ZIM-domain (JAZ) repressors to prevent the COI1-mediated JAZ degradation, thus blocking JA signaling transduction. HARP1-like proteins have conserved function as effectors in noctuidae, and these types of effectors might contribute to insect adaptation to host plants during coevolution. [ABSTRACT FROM AUTHOR]

Genetic diversity of cultivated soybean {Glycine max (L.) Merrill} 2n = 40 is very narrow, although includes diversity for many obvious morphological traits. A field experiment was conducted to study characterize of fifteen soybean genotypes on agro-morphological trait basis and to identify genetic diversity using SDS-PAGE, with resistance to defoliating insects, at Sakha Agricultural Research Station, Kafr ElShiekh, Egypt during 2017 and 2018 seasons,. Morphological description was performed with 10 qualitative and 7 quantitative traits and screening for defoliation by cotton leaf worm in the open field. The results exhibited significant differences among the tested fifteen genotypes for all studied characters. Defoliation of test plants by the cotton leaf worm, in the field screenings system showed that genotypes H14 L8, H1 L10S, H1 L10 and H10 L10 recorded the highest rating values of insect resistant to cotton leaf worm with defoliation rating (0.0 – 0.2), whereas, soybean genotype H5 L21 showed the highest insect susceptible and had defoliation rating (3.8) indicating heavy insect feeding, over both seasons. Genotypes H11 L145 and H14L8 recorded the highest values of seed yield/fad., this attributed to the considerable increase in their number of branches/plant, number of pods/plant, and 100-seed weight, in both seasons. This indicates that such genotypes are the promising ones. The protein identification indicated that the pattern was uniform where each genotype was not affected by year or location. The soybean genotypes were different in their banding pattern and each one is characterized by certain proteins with different molecular weight. Cluster analysis based on qualitative morphological characters showed clear separation of genotypes on the basis of their plant growth habit. [ABSTRACT FROM AUTHOR]

The role of infectious disease as a cause of death is undeniable. The affect infectious disease may have on decomposition after death is less well established. Furthermore, virtually no information is available regarding the effects of burial conditions in such circumstances, despite that numerous clandestine burials occur each year. Although many aspects of post-mortem pathology are well understood and provide frequent insight in medicolegal investigation, where buried bodies are concerned, there is great variation in the decomposition processes, depending on extrinsic and intrinsic conditions. Criminal burials and hurriedly dug clandestine graves are seldom deeper than 120 cm allowing access to certain invertebrates, excluding others that only develop in unburied bodies. Numerous studies have reported on such clandestine graves with a purpose to facilitate forensic investigation, but our knowledge of decomposition in deeper graves lags behind, despite several often-cited papers of over a century ago. The poor level of detail in deep-grave knowledge is in part due to resource deficiencies and ethical considerations, but in part due to lack of thorough investigation of the data in papers of often cited prior work. To this end, a metadata analysis assessed a paper written by Dr. Murray Galt Motter in 1898, providing detail of 150 disinterment events with linked medical records from City of Washington cemeteries. This paper, written more than a hundred years ago, was largely descriptive and the detailed data provided in a summary table were never fully analysed. The paper is often quoted despite these obvious oversights. The present study revisits this work, applying a frequency statistical analysis conducted using categorical data and chi-squared analysis. This new analysis reveals patterns and relationships so long 'locked-up' within the body of the table and provides greater understanding of the effect of infectious disease on the abundance of species in the entomofauna associated with deeply buried remains. The data confirm that the presence of adipocere (saponification) is detrimental to development of soil entomofauna ((X 2 = 6·64, df = 1, p < 0·01)). Some species, in particular Proisotoma sepulcralis (Collembola), Eleusis pallida (Coleoptera) and Conicera tibialis (Diptera), were positively influenced by association with infectious disease cases (p < 0·01) while only Piophila casei (Diptera) demonstrated a negative association (p < 0·05). Furthermore, the presence of peri-mortem infectious disease, while not necessarily a cause of death, influences post-mortem colonisation of the buried body by insects. The abundance of some species is enhanced, suggesting that bacterial burdens enhance decomposition in a manner favourable to insect feeding and hence abundance, by releasing compounds that the entomofauna feeds on. Unlabelled Image • Peri-mortem infection significantly affects decompositional of buried cadavers. • Entomofauna of buried cadavers is significantly affected by Peri-mortem infection. • Abundance of some Collembola, Coleoptera and Diptera increases with infectious burial/ • These indicator species show potential for investigating post-mortem interval/ • Presence or absence of peri-mortem infection can be determined post-mortem. [ABSTRACT FROM AUTHOR]

BACKGROUND It is difficult to efficiently silence gene expression in some insects, probably because of the degradation of dsRNA by enzymes present in the gut and hemolymph post‐oral feeding or body injecting of dsRNA. We previously developed a nanocarrier delivery system that can systemically deliver dsRNA into chewing mouthpart insects by oral feeding and efficiently silence gene expression. For the purpose of pest control in the field, there is a great demand to develop a spray method to apply dsRNA formulation. RESULTS: A formulation of the nanocarrier/dsRNA/detergent was developed and could be easily applied just by dropping it on the notum of the aphid. The formulation penetrated the body wall into the hemocoel and then spread into various tissues within 1 h. The delivered dsRNA efficiently silenced the target gene expression at a high knockdown effect (95.4%) and the aphid population was largely suppressed (80.5%). CONCLUSION: A novel dsRNA formulation was developed with the help of a nanocarrier and detergent that can quickly penetrate the insect body wall and efficiently silence gene expression. The formulation may provide a fast and easy tool for gene silence in some tough insects and for pest control in the field. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Plant perception of insect feeding involves integration of the multiple signals involved: wounding, oral secretions, and substrate borne feeding vibrations. Although plant responses to wounding and oral secretions have been studied, little is known about how signals from the rapidly transmitted vibrations caused by chewing insect feeding are integrated to produce effects on plant defenses. In this study, we examined whether 24 h of insect feeding vibrations caused changes in levels of phytohormones and volatile organic compounds (VOCs) produced by leaves of Arabidopsis thaliana when they were subjected to just feeding vibrations or feeding vibrations and wounding + methyl jasmonate (MeJA), compared to their respective controls of silent sham or wounding + MeJA. We showed that feeding vibrations alone caused a decrease in the concentrations of most phytohormones, compared to those found in control plants receiving no vibrations. When feeding vibrations were combined with wounding and application of MeJA, the results were more complex. For hormones whose levels were induced by wounding and MeJA (jasmonic acid, indole-3-butyric acid), the addition of feeding vibrations caused an even larger response. If the level of hormone was unchanged by wounding and MeJA compared with controls, then the addition of feeding vibrations had little effect. The levels of some VOCs were influenced by the treatments. Feeding vibrations alone caused an increase in β-ionone and decrease in methyl salicylate, and wounding + MeJA alone caused a decrease in benzaldehyde and methyl salicylate. When feeding vibrations were combined with wounding + MeJA, the effects on β-ionone and methyl salicylate were similar to those seen with feeding vibrations alone, and levels of benzaldehyde remained low as seen with wounding + MeJA alone. The widespread downregulation of plant hormones observed in this study is also seen in plant responses to cold, suggesting that membrane fluidity changes and/or downstream signaling may be common to both phenomena. [ABSTRACT FROM AUTHOR]

Phyllophaga ravida Blanchard and Phyllophaga opaca Moser (Coleoptera: Scarabaeoidea: Melolonthidae) are economically important in Mexico. An option for management of the insect pests is use of sex pheromones. To obtain the chemical profile of sex pheromones of both species the posterior section of the genital chamber of females was excised and macerated to release the contents. Eight compounds from P. ravida were identified by retention index and mass spectra: cyclohexane, 1,1???-(2-tridecyl-1,3-propanediyl) bis-; 10-methyl-eicosane; 5-butyl-hexadecane; 3-hexen-2-one; 3,3-diethyl-azetidine-2,4-dione; tetramethyl-oxirane; 3-methyl-2-pentanone; and 2-methoxy-2-methyl-butane. Seven compounds were identified for P. opaca: cholesta-4, 6-dien-3-ol; cholesterol; cholesta-3,5-dien; 2-methyl heptadecane; ??-tocopherol succinate; 9,19-cyclolanost-24-en-3-ol, acetate; and lup-20 (29)-en-3-ol, acetate. Some identified chemicals, mainly 3,3-diethyl-azetidine-2,4-dione and 2-methyl heptadecane might be involved in sexual attraction of P. ravida and P. opaca, respectively. Several compounds probably are incorporated from plants into insects during feeding, and further transformed by metabolism. [ABSTRACT FROM AUTHOR]

1. Dung beetles are commonly assumed to be generalist feeders, but there has been limited work in identifying whether there is interspecific variation in feeding preference. Equally, there has been no work exploring whether generalist feeding behaviour in a species is a result of within‐species specialisation. 2. This study identified the individual and species‐level feeding preferences of five dung beetle species towards human, jaguar and pig dung using a choice experiment. 3. It was found that species varied in their preference for the dung types, but there was no evidence that within a species, individual beetles varied in their dung choice. These findings were similar to results from field experiments that are more typically used to assess feeding preferences in dung beetles. 4. The results suggest that individual specialism in feeding may not be common in dung beetles. However, there is variation in feeding preferences among species, which is often overlooked and can have implications for the ecosystem functions they provide. It is suggested that choice arenas can be used to assess feeding preferences in dung beetle species that are not abundant enough to reliably estimate dietary choice from field studies. [ABSTRACT FROM AUTHOR]

A study was designed to evaluate the combined effects of age, mating status and sex on the feeding attributes of the Parthenium beetle, Zygogramma bicolorata Pallister when fed on Parthenium hysterophorus L., a serious weed of wastelands, pastures and agricultural fields. Newly emerged adult beetles were placed in two groups. Adults of the first group were kept unmated and their daily feeding and growth attributes were assessed for the following 20 days. By comparison, males and females of the second group were allowed to mate on the 11th day (attainment of sexual maturity) and mating pairs were kept individually to assess their daily feeding and growth attributes for the following 10 days. Results revealed higher consumption and growth rates of Z. bicolorata females than males. In contrast, males exhibited higher food conversion efficiencies than the females. However, food consumption and growth rates of unmated adults were higher than mated adults. Agebased regression graphs revealed decreased consumption rates, conversion efficiencies and growth rates of Z. bicolorata adults with increase in age. However, the mean body biomass of adults increased with increasing age. This further suggested compensatory feeding in Z. bicolorata adults as they age. The present findings may be helpful to mass-multiply Z. bicolorata in laboratories for the biocontrol of Parthenium weed in agricultural farms on the Indian subcontinent. [ABSTRACT FROM AUTHOR]