Beetle Tribolium Castaneum Research Articles

Phytochemical characterization and bioactivities of different fruit parts of Tunisian barbary fig (Opuntia ficus-indica)

The valorization of bio-waste to acquire products with high added value presents a great profit for the pharmaceutical, medicinal and food industries. Thus, seeds, peels, and pulps obtained from green (GFI), orange (OFI), and purple (PFI) Tunisian pear fruit (Opuntia ficus-indica L.) were evaluated in terms of phytochemical composition and biological activities. The peel part of the purple fruit contained the highest content of K, Ca, and Mg. While the seed possessed the highest P and Fe amounts. Moreover, the total carbohydrate contents in the different pear fruit parts ranged from 43.41% in the seeds (GFI) to 68.12% in pulp parts (OFI) and were significantly different from each other. The pulp parts showed much higher xylose and fructose contents, averaging 3.38 and 119.17 g/L. The seeds of the three varieties were characterized by higher levels of polyunsaturated fatty acids and mostly predominated by oleic acid that varied from 43.51 to 47.84% for the green and orange colored fruit seeds, followed by linoleic acid (32.76—37.1%). The seeds and peels parts contained higher levels of phenolic compounds with a total of 37 compounds compared to pulp extracts. The seeds of the three studied fruits possessed high repellency potentials against the red flour beetle (Tribolium castaneum). The greatest repellency activities were recorded in the purple (53.33%) and the orange (46.66%) fruit seeds at the concentration of 5 μL/cm2 and after 1h of exposure. The fruit parts showed considerable antibacterial and antifungal effects against Erwinia amylovora and Botrytis cinerea. The prickly pear fruit could be used as natural ingredients with potential biological activities.

Aggregation pheromone interrupts death feigning in the red flour beetle Tribolium castaneum

AbstractDeath feigning is a behavior in which a prey is rendered motionless due to stimulation or threat by a predator. This anti-predator defense mechanism has been observed across a wide range of animal taxa and is considered adaptive. However, long durations of death feigning can decrease opportunities for feeding and reproduction, and therefore is a fitness cost as compared to environments without predators. Because death feigning is thought to be affected by the balance between survival and other fitness costs, selection pressure may drive individuals who are capable of plastic changes in the intensity of death feigning. Pheromones, which are important semiochemicals that affect foraging and reproductive success, may be one of the factors influencing the intensity of death-feigning behavior. In this study, we investigated the effect of an aggregation pheromone on the death-feigning behavior of the red flour beetle Tribolium castaneum. We found that beetles exposed to the pheromone showed a significantly shorter duration of death feigning than beetles that were not exposed to the pheromone. Therefore, our results suggest that an aggregation pheromone can plasticly alter the death-feigning behavior in T. castaneum.

The impact of UV-C radiation on the sugar metabolism of the red flour beetle Tribolium castaneum herbst (coleoptera; tenebrionidae)

Purpose Ultraviolet-C (UV-C) is known to induce morphological abnormality in various parts of the red flour beetle, Tribolium castaneum, including its wings, antennae, eyes, legs, and reproductive organs. However, little is known about the effects of UV-C on T. castaneum’s sugar content and enzyme activity. Material and methods We investigated the concentrations of glucose and trehalose as well as changes in trehalase activity in different developmental stages following UV-C radiation at different exposure periods (1, 2, 4, 8, 16, 32, and 64 min). In addition, the larval mortality and body weight were examined. Results A reduction in glucose content was recorded in 10-, 15- and 20-day-old larvae and trehalase enzyme activity was recorded in 5- and 10-day-old larvae, whereas an increase in trehalose content was found in adults irradiated with UV-C. In addition, UV-C radiation for 1–64 min caused larval mortality on the first and subsequent days post-irradiation. Moreover, UV-C irradiated larvae exhibited lower body weight, which aligned with the reduction of trehalase activity and glucose content from days 1–6 post-exposure, and the degree of these reductions corresponded to the exposure times. Conclusion UV-C affected sugar content through the reduction of trehalase activity, and glucose declination may cause mortality in T. castaneum; however, further research is needed to provide a better understanding of the impact of UV-C on sugar metabolism.

Fumigant Toxicity and Repellent Effect of Propolis Oil Against Adults and Third Instar Larvae of Red Flour Beetle Tribolium castaneum (Herbst), (Coleoptera:Tenebrionidae)

Fumigant Toxicity and Repellent Effect of Propolis Oil Against Adults and Third Instar Larvae of Red Flour Beetle Tribolium castaneum (Herbst), (Coleoptera:Tenebrionidae)

Sublethal Exposure Enhances Suspectibility to Phoshine and Effects Certain Fitness Traits in Red Flour Beetle <i>Tribolium castaneum</i> (Herbst)

The insecticidal gaseous phosphine would fail to meet the required concentration owing to improper sealing in a majority of bulk storage units. The resulting sublethal concentration has toxicological and biological implications for the target pests. The red flour beetle Tribolium castaneum has developed considerable resistance to phosphine. In this study, the effect of sublethal phosphine (LC25 and LC40) dose exposure is seen in the first filial generation of T. castaneum, where it was found to increase the susceptibility of the F1 generation. The lethal concentration (LC50) of parent stock (0.076 mg/ l) was reduced to 0.059 mg/ l and 0.052 mg/ l in the F1 generation, respectively in the sample prior exposed to sublethal doses of LC25 and LC40. Surviving females of sublethal exposures (LC40 and LC25) produced fewer offspring with a cumulative fecundity reduction of 21 and 84% respectively, compared to parent stock. The variables tested in PCA highlight the negative effect of sublethal dose on the fecundity and fitness of female adults.

The Intricate Role of Ecdysis Triggering Hormone Signaling in Insect Development and Reproductive Regulation.

Insect growth is interrupted by molts, during which the insect develops a new exoskeleton. The exoskeleton confers protection and undergoes shedding between each developmental stage through an evolutionarily conserved and ordered sequence of behaviors, collectively referred to as ecdysis. Ecdysis is triggered by Ecdysis triggering hormone (ETH) synthesized and secreted from peripheral Inka cells on the tracheal surface and plays a vital role in the orchestration of ecdysis in insects and possibly in other arthropod species. ETH synthesized by Inka cells then binds to ETH receptor (ETHR) present on the peptidergic neurons in the central nervous system (CNS) to facilitate synthesis of various other neuropeptides involved in ecdysis. The mechanism of ETH function on ecdysis has been well investigated in holometabolous insects such as moths Manduca sexta and Bombyx mori, fruit fly Drosophila melanogaster, the yellow fever mosquito Aedes aegypti and beetle Tribolium castaneum etc. In contrast, very little information is available about the role of ETH in sequential and gradual growth and developmental changes associated with ecdysis in hemimetabolous insects. Recent studies have identified ETH precursors and characterized functional and biochemical features of ETH and ETHR in a hemimetabolous insect, desert locust, Schistocerca gregaria. Recently, the role of ETH in Juvenile hormone (JH) mediated courtship short-term memory (STM) retention and long-term courtship memory regulation and retention have also been investigated in adult male Drosophila. Our review provides a novel synthesis of ETH signaling cascades and responses in various insects triggering diverse functions in adults and juvenile insects including their development and reproductive regulation and might allow researchers to develop sustainable pest management strategies by identifying novel compounds and targets.

Restoration of energy homeostasis under oxidative stress: Duo synergistic AMPK pathways regulating arginine kinases.

Rapid depletion of cellular ATP can occur by oxidative stress induced by reactive oxygen species (ROS). Maintaining energy homeostasis requires the key molecular components AMP-activated protein kinase (AMPK) and arginine kinase (AK), an invertebrate orthologue of the mammalian creatine kinase (CK). Here, we deciphered two independent and synergistic pathways of AMPK acting on AK by using the beetle Tribolium castaneum as a model system. First, AMPK acts on transcriptional factor forkhead box O (FOXO) leading to phosphorylation and nuclear translocation of the FOXO. The phospho-FOXO directly promotes the expression of AK upon oxidative stress. Concomitantly, AMPK directly phosphorylates the AK to switch the direction of enzymatic catalysis for rapid production of ATP from the phosphoarginine-arginine pool. Further in vitro assays revealed that Sf9 cells expressing phospho-deficient AK mutants displayed the lower ATP/ADP ratio and cell viability under paraquat-induced oxidative stress conditions when compared with Sf9 cells expressing wild-type AKs. Additionally, the AMPK-FOXO-CK pathway is also involved in the restoration of ATP homeostasis under oxidative stress in mammalian HEK293 cells. Overall, we provide evidence that two distinct AMPK-AK pathways, transcriptional and post-translational regulations, are coherent responders to acute oxidative stresses and distinguished from classical AMPK-mediated long-term metabolic adaptations to energy challenge.

Female investment in terminal reproduction or somatic maintenance depends on infection dose

Abstract Immune responses are energetically costly to produce and often trade off with investment in reproduction and offspring provisioning. We predicted that hosts can interpret the magnitude of the infection threat from cues like initial bacterial load to adjust reproductive investment into offspring quantity and quality. To test this prediction, we exposed female flour beetles (Tribolium castaneum) to naïve or sterile media controls or one of three increasing doses of heat‐killed Bacillus thuringiensis (Bt). To estimate offspring quantity, we measured the number of eggs and hatched larvae from each maternal treatment group. To estimate offspring quality, we measured egg protein content, development to pupation, pupal weight and offspring survival against Bt infection. Compared to naïve controls, low and intermediate bacterial doses resulted in lower female fecundity, suggesting a shift to a somatic maintenance strategy. Meanwhile, in the highest‐dose group, fecundity was negatively correlated with egg protein content. This may reflect a trade‐off between offspring quality and quantity that could mask terminal investment based on metrics of quantity alone. Our results underscore the need to account for the magnitude of environmental cues when quantifying plasticity and trade‐offs among life history traits, and provide new insight into the transgenerational effects of immune responses.

Bioactivity-guided isolation of toosendanin and salanninolide from Melia volkensii and their antifeedant activity against economically important insect pests

The fall armyworm (Spodoptera frugiperda), sweet potato weevil (Cylas puncticollis) and red flour beetle (Tribolium castaneum) are insect pests of economic importance that negatively impact production of maize, sweet potato and stored grain, respectively. The continued use of synthetic insecticides to control these insect pests can cause undesirable effects to the environment, human, and other non-target organisms, leading to renewed interest in botanical pesticides as a safer alternative. In this study, bioactivity-guided strategy was applied to isolate insect antifeedants from Melia volkensii, a native tree species to the drylands of East Africa. Initial laboratory screening of M. volkensii nut and pulp crude extracts showed antifeedant activity against S. frugiperda, C. puncticollis and T. castaneum in our previous publication. Fractionation of the nut and pulp crude extracts using various solvents of increasing polarity showed that the antifeedant activity was retained in the dichloromethane fraction, which was subsequently purified by column chromatography. The resultant bioactive fractions were further purified by preparative-HPLC, preparative-TLC and recrystallization, which yielded two pure bioactive compounds characterized as toosendanin and salanninolide using NMR and LC-MS. Toosendanin and salanninolide showed strong activity against T. castaneum and S. frugiperda, with EC50 values of 0.11% and 0.14%, and 0.15% and 0.10%, respectively. In contrast, there was no antifeedant activity by both isolated compounds against C. puncticollis. This study provides new leads for development of insect control products from M. volkensii.

How enhancers regulate wavelike gene expression patterns.

A key problem in development is to understand how genes turn on or off at the right place and right time during embryogenesis. Such decisions are made by non-coding sequences called 'enhancers.' Much of our models of how enhancers work rely on the assumption that genes are activated de novo as stable domains across embryonic tissues. Such a view has been strengthened by the intensive landmark studies of the early patterning of the anterior-posterior (AP) axis of the Drosophila embryo, where indeed gene expression domains seem to arise more or less stably. However, careful analysis of gene expression patterns in other model systems (including the AP patterning in vertebrates and short-germ insects like the beetle Tribolium castaneum) painted a different, very dynamic view of gene regulation, where genes are oftentimes expressed in a wavelike fashion. How such gene expression waves are mediated at the enhancer level is so far unclear. Here, we establish the AP patterning of the short-germ beetle Tribolium as a model system to study dynamic and temporal pattern formation at the enhancer level. To that end, we established an enhancer prediction system in Tribolium based on time- and tissue-specific ATAC-seq and an enhancer live reporter system based on MS2 tagging. Using this experimental framework, we discovered several Tribolium enhancers, and assessed the spatiotemporal activities of some of them in live embryos. We found our data consistent with a model in which the timing of gene expression during embryonic pattern formation is mediated by a balancing act between enhancers that induce rapid changes in gene expression patterns (that we call 'dynamic enhancers') and enhancers that stabilize gene expression patterns (that we call 'static enhancers'). However, more data is needed for a strong support for this or any other alternative models.

Repellent activity of basil, clary sage and celery essential oils on Tribolium castaneum (Herbst)

A two-arm olfactometer was used in experiments to determine the effect of different concentrations (0.01, 0.1, and 1%) of essential oils of basil (Ocimum basilicum), clary sage (Salvia sclarea), and celery seed (Apium graveolens) on the behaviour of the red flour beetle (Tribolium castaneum). In the first experiment, the effect of the tested essential oils on mixed-sex T. castaneum was examined, while in the second experiment, the same effect was examined on males and females of this species, separately. The results showed that basil and clary sage essential oils repelled mixed sexes of T. castaneum at all tested concentrations, while celery seed oil, at a concentration of 1%, exhibited a repellent effect, at 0.1%, a neutral effect, and at 0.01%, an attractive effect. T. castaneum male and female behaviour differed in subsequent studies. Celery seed essential oil was attractive to males and females at the lowest concentration (0.01%); at the middle concentration, it was repellent to males but attractive to females, while at the highest concentration, it was repellent to both males and females. Basil essential oil, at the lowest concentration (0.01%), also had a repellent effect on males but not on females. Better knowledge of the behaviour of this pest can contribute to the development of new methods of store product protection.

Latitudinal cline in reproductive traits in the red flour beetle Tribolium castaneum

Several previous studies have reported geographic variation and/or latitudinal clines of morphological sexual characteristics, but there are few studies that consider reproductive traits that are not morphological. Here, we measured the proportion of females fertilized by males, frequency of reproductive failure in males, and number of female copulations of the red flour beetle Tribolium castaneum collected from fields in Japan to investigate the relationship between reproductive traits and latitude. Our results show substantial differences in the reproductive traits of both sexes among field populations. We identified latitudinal clines for reproductive traits in males, but not females. Moreover, female, but not male, reproductive traits were correlated with body size. Our study suggests that selection for male reproductive traits varies with latitude in T. castaneum.Significance statementIt has been established that latitudinal gradients are frequently observed in the traits of numerous animal species, of which body size is a prime example. Analogously, latitudinal gradients have been documented in the reproductive traits of several animal species, indicating that sexual selection may be influenced by latitude, although the specific understanding thereof remains elusive. In this study, we quantified the male and female reproductive traits and analyzed their relationship with latitude in the red flour beetle Tribolium castaneum. Our findings indicate that male mating efficacy was superior at lower than at higher latitudes, but no discernible latitudinal gradient was observed in female mating frequency. These results imply that selective pressure on males of this species is stronger at lower than at higher latitudes.

Transcriptomic analysis of the insecticidal activities of methyl benzoate against red flour beetle Tribolium castaneum (Herbst) larvae

Methyl benzoate (MB) is a common component of floral scents released by many plants. Recent research showed that MB was an alternative insecticide to control insect pests. However, the molecular mechanisms of insect pests in responses to MB are largely unknown, which limits the future applications of this promising insecticidal candidate. In this study, the total transcriptomic analysis for red flour beetle larvae after MB fumigation was performed. Of the 430 identified differentially expressed genes, 197 were upregulated and 233 were downregulated. GO and KEGG pathway enrichment were used to interpret gene classification/function and metabolic/signaling pathways, respectively. And we performed RT-qPCR to validate expressional profiles of identified DEGs. Genes that are involved in energy metabolism, xenobiotic metabolism, and digestive enzymes were shown to be differentially expressed, suggesting that MB have an impact on these physiological processes. This research will enrich our knowledge about the mechanisms of MB-fumigation response genes for stored-product pests. A better understanding of molecular response to MB will facilitate future applications to control stored-product pests.

Characterization of Glutamate-Gated Chloride Channel in Tribolium castaneum.

The glutamate-gated chloride channels (GluCls) play essential roles in signal transduction by regulating fast inhibitory synaptic transmission in the nervous system of invertebrates. While there is only one GluCl subunit in the insect, the diversity of insect GluCls is broadened by alternative splicing. In the present study, three TcGluCl variant genes were cloned from the red flour beetle Tribolium castaneum. Analysis of the characteristics of TcGluCls including sequence features, genomic structures, and alternative splicing revealed that TcGluCls had the typical structural features of GluCls and showed high homologies with the GluCls from other insect orders. The TcGluCl-encoding gene consists of nine exons and three variants (TcGluCl-3a, TcGluCl-3b, and TcGluCl-3c) were generated by the alternative splicing of exon 3, which was a highly conserved alternative splicing site in insect GluCls. Homology modeling of TcGluCl-3a showed that the exon 3 coding protein located at the N-terminal extracellular domain, and there were no steric clashes encountered between the exon 3 coding region and ivermectin/glutamate binding pocket, which indicated that the alternative splicing of exon 3 might have no impact on the binding of GluCls to glutamate and insecticide. In addition to the head tissue, TcGluCl-3a and TcGluCl-3c also had high expressions in the ovary and testis of T. castaneum, whereas TcGluCl-3b showed high expression in the midgut, suggesting the diverse physiological functions of TcGluCl variants in T. castaneum. The total TcGluCl and three variants showed the highest expression levels in the early stage larvae. The expressions of TcGluCl, TcGluCl-3b, and TcGluCl-3c were significantly increased from the late-stage larvae to the early stage pupae and indicated that the TcGluCl might be involved in the growth and development of T. castaneum. These results are helpful to further understand the molecular characteristics of insect GluCls and provide foundations for studying the specific function of the GluCl variant.

Antifeedant and growth disruption activities of five phytoecdysteroids in the red flour beetle Tribolium castaneum: structure-activity relationship

Antifeedant and growth disruption activities of five phytoecdysteroids in the red flour beetle Tribolium castaneum: structure-activity relationship

Experimental arena settings might lead to misinterpretation of movement properties.

Movement is an important animal behavior contributing to reproduction and survival. Animal movement is often examined in arenas or enclosures under laboratory conditions. We used the red flour beetle (Tribolium castaneum) to examine here the effect of the arena size, shape, number of barriers, access to the arena's center, and illumination on six movement properties. We demonstrate great differences among arenas. For example, the beetles moved over longer distances in clear arenas than in obstructed ones. Movement along the arena's perimeter was greater in smaller arenas than in larger ones. Movement was more directional in round arenas than in rectangular ones. In general, the beetles stopped moving closer to the perimeter and closer to corners (in the square and rectangular arenas) than expected by chance. In some cases, the arena properties interacted with the beetle sex to affect several movement properties. All these suggest that arena properties might also interact with experimental manipulations to affect the outcome of studies and lead to results specific to the arena used. In other words, instead of examining animal movement, we in fact examine the animal interaction with the arena structure. Caution is therefore advised in interpreting the results of studies on movement in arenas under laboratory conditions and we recommend paying attention also to barriers or obstacles in field experiments. For instance, movement along the arena's perimeter is often interpreted as centrophobism or thigmotaxis but the results here show that such movement is arena dependent.

Effect of Microwave Radiation on the Red Flour Beetle <i>Tribolium castaneum</i> (Herbst)

Approximately 50% of total harvested cereal grains are lost during the post-harvest handling and storage, and insects are the main cause for both quantity (reductions in weight) and quality. In the present study the effect of microwave radiation was studied on one of the stored product pest, the flour beetle Tribolium castaneum (Hersbt). Adult insects were obtained from infested flour products at stores specialized in selling cereal and stored products from Sakaka. Insects with its food media inside sac were exposed to microwave radiation for 15, 30, 45 and 60 sec for each radiation power. Tribolium castaneum beetles were exposed to microwave for 15, 30 and 45 sec. This result revealed that the mortality of immature and adults reached 100% in 15 and 45 sec, respectively.

The Low-Copy-Number Satellite DNAs of the Model Beetle Tribolium castaneum.

The red flour beetle Tribolium castaneum is an important pest of stored agricultural products and the first beetle whose genome was sequenced. So far, one high-copy-number and ten moderate-copy-number satellite DNAs (satDNAs) have been described in the assembled part of its genome. In this work, we aimed to catalog the entire collection of T. castaneum satDNAs. We resequenced the genome using Illumina technology and predicted potential satDNAs via graph-based sequence clustering. In this way, we discovered 46 novel satDNAs that occupied a total of 2.1% of the genome and were, therefore, considered low-copy-number satellites. Their repeat units, preferentially 140-180 bp and 300-340 bp long, showed a high A + T composition ranging from 59.2 to 80.1%. In the current assembly, we annotated the majority of the low-copy-number satDNAs on one or a few chromosomes, discovering mainly transposable elements in their vicinity. The current assembly also revealed that many of the in silico predicted satDNAs were organized into short arrays not much longer than five consecutive repeats, and some of them also had numerous repeat units scattered throughout the genome. Although 20% of the unassembled genome sequence masked the genuine state, the predominance of scattered repeats for some low-copy satDNAs raises the question of whether these are essentially interspersed repeats that occur in tandem only sporadically, with the potential to be satDNA "seeds".

Multiple Pesticide Resistance in Rust-Red Flour Beetle (Tribolium castaneum, Herbst 1797) from Northern Nigeria Is Probably Driven by Metabolic Mechanisms

There is a severe lack of information about molecular mechanisms of pesticide resistance in the rust-red flour beetle, a major pest destroying grains and flour across Nigeria, hindering evidence-based control. Here, we identified to the species level three populations of the red flour beetle from Kano, Nigeria, as Tribolium castaneum (Herbst 1797) and investigated the mechanism driving their insecticide resistance. The IRAC susceptibility bioassays established cypermethrin resistance, with LC50s of 4.35–5.46 mg/mL in the three populations, NNFM, R/Zaki and Yankaba. DDT and malathion resistance were observed in NNFM, with LC50s of 15.32 mg/mL and 3.71 mg/mL, respectively. High susceptibility was observed towards dichlorvos in all three populations with LC50s of 0.17–0.35 mg/mL. The synergist bioassay with piperonylbutoxide significantly restored cypermethrin susceptibility, with mortality increasing almost threefold, from 24.8% obtained with 1.5 mg/mL of cypermethrin to 63.3% in the synergised group (p = 0.013), suggesting a preeminent role of P450s. The two major knockdown resistance (kdr) mutations, T929I and L1014F, in the IIS4 and IIS6 fragments of the voltage-gated sodium channel were not detected in both cypermethrin-alive and cypermethrin-dead beetles, suggesting a lesser role of target-site insensitivity mechanisms. These findings highlight the need to explore alternative control tools for this pest and/or utilise synergists, such as piperonyl butoxide, as additional chemistries in pesticide formulations to improve their efficacy.

Morphological shifts in response to spatial sorting of dispersal behaviour in red flour beetles across multiple generations

AbstractDispersal is a key component of life history that influences individual fitness, population dynamics and range expansion. Morphological traits that are functionally related to dispersal may change through the spatial sorting of phenotypes at population range edges and invasion fronts. Generally, since larger invertebrates are expected to have greater dispersal capacity, larger body size and mass is expected to evolve in dispersers. Yet, different study systems exhibit a range of trait‐specific and sex‐specific responses to spatial sorting. Furthermore, a persistent issue in this field is that spatial sorting can be challenging to separate from natural selection and population dynamics. To address this, here we investigated the responses of dispersal and morphological traits to simulated spatial sorting into disperser and non‐disperser red flour beetles (Tribolium castaneum) using a controlled laboratory dispersal system that isolated spatial sorting from natural selection and allowed sex‐specific dispersal traits to evolve independently. After seven generations of spatial sorting, the time taken to disperse decreased in dispersers and increased in non‐dispersers, with males dispersing more quickly than females. In contrast to expectations that dispersers would increase in body mass and size, we found the opposite. Body mass and morphology diverged such that dispersers became smaller and narrower, while non‐dispersers became larger relative to the randomly selected controls, but femur length did not change. The trait responses across generations were also sex specific. Divergence between male dispersers and non‐dispersers was more substantial than females, both in dispersal and in some morphological traits. We hypothesize that small individuals were more biomechanically efficient at dispersing through the dispersal apparatus and were therefore the ones that dispersed more readily. We suggest that key differences in dispersal modes across biological systems may impact the morphological and phenotypic trait changes from spatial sorting processes in range expansions and biological invasions.