Arthropod Populations Research Articles

Refuge plants and jajar legowo systems increasing the useful arthropods population and the rice yield

Ecological engineering has become a promising strategy for restoring paddy field biodiversity and enhancing yield. This study aims to evaluate the effectiveness of refuge plants and cropping systems on the population of useful arthropods and rice production. The study was conducted on a paddy field in Central Sulawesi, Indonesia, using a Split Plot Design. The main plots were refuge plants with four treatments, namely rice without refuge crops, rice crops with wild Cosmos (C. caudatus), marigold (Tagetes erecta), and both flower plants as the refuges, whereas two cropping systems, i.e., the jajar legowo system (JLS) of 2:1 and the symmetries system (SS) was set up as a sub-plot. Direct observation and collection of the arthropods were carried out using yellow-pan traps and a sweep net. The parasitoid eggs were reared at the laboratory. In addition, rice growth and yields were measured. The refuge plants and cropping system had no significant effects on the overall arthropods population but changed their diversity and community structure and increased the proportion of useful arthropods as well. Meanwhile, rice production in the JLS (5.16 tons GKG ha−1) was significantly higher than those of the SS (4.10 tons GKG ha−1), and this was in line with the differences in the panicles number in both cropping systems. The study highlighted the importance of the implementation of ecological engineering at the paddy fields by using the flower plants as the refuge and food sources for the beneficial organisms combined by JLS for enhancing the rice yields.

Pesticides in the Great Barrier Reef catchment area: Plausible risks to fish populations.

Waterways that drain the Great Barrier Reef catchment area (GBRCA) transport pollutants to marine habitats, provide a critical corridor between freshwater and marine habitats for migratory fish species, and are of high socioecological value. Some of these waterways contain concentrations of pesticide active ingredients (PAIs) that exceed Australian ecotoxicity threshold values (ETVs) for ecosystem protection. In this article, we use a "pathway to harm" model with five key criteria to assess whether the available information supports the hypothesis that PAIs are or could have harmful effects on fish and arthropod populations. Strong evidence of the first three criteria and circumstantial weaker evidence of the fourth and fifth criteria are presented. Specifically, we demonstrate that exceedances of Australian and New Zealand ETVs for ecosystem protection are widespread in the GBRCA, that the PAI contaminated water occurs (spatially and temporally) in important habitats for fisheries, and that there are clear direct and indirect mechanisms by which PAIs could cause harmful effects. The evidence of individuals and populations of fish and arthropods being adversely affected species is more circumstantial but consistent with PAIs causing harmful effects in the freshwater ecosystems of Great Barrier Reef waterways. We advocate strengthening the links between PAI concentrations and fish health because of the cultural values placed on the freshwater ecosystems by relevant stakeholders and Traditional Owners, with the aim that stronger links between elevated PAI concentrations and changes in recreationally and culturally important fish species will inspire improvements in water quality. Integr Environ Assess Manag 2024;20:1256-1279. © 2023 Commonwealth of Australia and The Commonwealth Scientific and Industrial Research Organisation. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Arthropod anthropocenes: A call for action

The editorial "Arthropod Anthropocenes: A Call for Action" emphasizes the critical role arthropods play in maintaining ecological balance and biodiversity in the Anthropocene, an era defined by significant human impact on Earth's ecosystems. Highlighting the urgent need to address threats such as habitat destruction, climate change, and pollution, the piece advocates for sustainable practices to conserve arthropod populations. It calls for integrated efforts including enhanced research, sustainable agricultural practices, urban biodiversity enhancement, climate change mitigation, public education, policy and legislation reform, and international collaboration to safeguard arthropods and ensure the health of global ecosystems. This comprehensive approach underscores the indispensable role of arthropods in sustaining life on Earth, making a case for their conservation as a moral imperative for collective action.

Variation in temperature of peak trait performance constrains adaptation of arthropod populations to climatic warming

The capacity of arthropod populations to adapt to long-term climatic warming is currently uncertain. Here we combine theory and extensive data to show that the rate of their thermal adaptation to climatic warming will be constrained in two fundamental ways. First, the rate of thermal adaptation of an arthropod population is predicted to be limited by changes in the temperatures at which the performance of four key life-history traits can peak, in a specific order of declining importance: juvenile development, adult fecundity, juvenile mortality and adult mortality. Second, directional thermal adaptation is constrained due to differences in the temperature of the peak performance of these four traits, with these differences expected to persist because of energetic allocation and life-history trade-offs. We compile a new global dataset of 61 diverse arthropod species which provides strong empirical evidence to support these predictions, demonstrating that contemporary populations have indeed evolved under these constraints. Our results provide a basis for using relatively feasible trait measurements to predict the adaptive capacity of diverse arthropod populations to geographic temperature gradients, as well as ongoing and future climatic warming.

Insects and spiders on Acacia mangium (Fabaceae) saplings as bioindicators for the recovery of tropical degraded areas.

Acacia mangium is a pioneer species with fast growth and frequently used in the recovery of degraded areas. The objectives were to evaluate insects and spiders, their ecological indices and interactions on A. mangium saplings in a tropical degraded area in recovering process. The experimental design was completely randomized with 24 replications, with treatments represented by the first and second years after A. mangium seedling planted. Numbers of leaves/branch, branches/sapling, and ground cover by A. mangium saplings, Hemiptera: Phenacoccus sp. and Pachycoris torridus; Hymenoptera: Tetragonisca angustula and Trigona spinipes, Brachymyrmex sp., Camponotus sp. and Cephalotes sp.; Blattodea: Nasutitermes sp. and Neuroptera: Chrysoperla sp.; abundance, species richness of pollinating insects, tending ants, and the abundance of Sternorrhyncha predators were greatest in the second year after planting. Numbers of Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, tending ants, pollinating insects, Sternorrhyncha predators and species richness of tending ants were highest on A. mangium saplings with greatest numbers of leaves or branches. The increase in the population of arthropods with ground cover by A. mangium saplings age increase indicates the positive impact by this plant on the recovery process of degraded areas.

Subcellular biochemistry and biology of filamentous entomopathogenic fungi.

Filamentous entomopathogenic fungi (EPF) function as important biotic factors regulating the arthropod population in natural ecosystems and have great potential as biocontrol agents in modern agriculture. In the infection cycle, EPF undergo a plethora of physiological processes, including metabolism (e.g., cuticle hydrolysis and nutrient utilization), development (e.g., dimorphism and conidiation), stress response (e.g., oxidative and osmotic stresses), and immune evasion from the host. In-depth explorations of the mechanisms involved in the lifecycle of EPF offer excellent opportunities to increase their virulence and stability, which increases the efficacy of EPF in biocontrol programs. This review discusses the current state of knowledge relating to the biological roles and regulatory mechanisms of organelles and subcellular structures in the physiology of EPF, as well as some suggestions for future investigation.

Comparison of Arthropod Diversity in Organic and Conventional Rice Cultivation in Trawas District, Mojokerto Regency

Different cultivation techniques for rice (Oryza sativa L.) are known to affect arthropod populations and diversity levels. This research was conducted to study how arthropod diversity can be affected by different cultivation techniques. The research was carried out from October 2022 to March 2023. Arthropod diversity observations were carried out in the organic rice field of Kampung Pertanian Organik Brenjonk and a conventional rice field belonging to a farmer in Penanggungan Village, Trawas District, Mojokerto Regency. Data were collected weekly for 12 observations. Arthropods were collected using passive methods, such as pitfall and yellow sticky traps, and active methods, such as sweep netting and handpicking. The data were analyzed to assess the diversity level. The results showed more arthropods in the organic rice field, with 1815 individuals consisting of 4 classes, 13 orders, 52 families, 70 genera, and 74 morphospecies. In contrast, in the conventional rice field, 1028 individuals were found, consisting of 3 classes, ten orders, 28 families, 32 genera, and 33 morphospecies. The calculation results of arthropod diversity levels showed that the organic field is better than the conventional field.

Fostering Biodiversity: Unleashing the Potential of Refugia to Enhance Arthropod Diversity in Chili (Capsicum annuum L.) Farms

Background: The utilization of Integrated Pest Management (IPM) offers a solution to chili cultivation pest challenges by implementing ecological engineering strategies, such as planting refugia. These refugia serve as SNAP (Shelter, Nectar, Alternative Food, and Pollen) sources for beneficial insects. This study aimed to assess the impact of refugia planting on arthropod-type diversity and explore the influence of abiotic factors on arthropod populations. Methods: Conducted from February to May 2023, the research utilized various traps (sweep net, yellow trap, pitfall trap, and light trap) and visual control for specimen collection. Results: The identification revealed the presence of three classes, ten orders, and 31 families. Arthropod populations in chilli fields with refugia totaled 867 individuals, whereas those without refugia amounted to 475. Conclusions: Planting refugia led to an elevated diversity index and evenness of arthropods, coupled with a lower dominance index compared to fields without refugia. Surprisingly, temperature and air humidity did not exhibit a significant impact on the arthropod population in chilli fields.

Use of Locally Food Attractants for Ceratitis capitata (Diptera: Tephritidae)

The high price of commercial products against pests impose small farmers to use a locally available baits against C.capitata that is the most fruit fly in our country. The aim of this research was to evaluate the effectiveness of food-based attractants for the capture of C. capitata as well as their selectivity on the populations of beneficial arthropods. we tested some local fermentation products compared to commercial lures (CeraTrap®). Four attractants were evaluated in two peach orchads. Field evaluations show that local fermentation products, particularly the red wine solution outperformed other food-based attractants. However, the average of fruit damage was differed between the four attractants and it was high in the border than in the center of each attractants plot. These attractants also were selective, capturing few beneficial arthropods. It will be necessary to focus our research on how to optimally employ such a trap in conjunction or alternative with other control techniques to drive concerted and integrated pest management due to its low environmental impacts and selectivity toward beneficial insects.

Arthropods discovered on refugio flowering plants in Mangifera indica plantation

Abstract. Windriyanti W, Rahmadhini N, Fernando I, Kusuma RM. 2023. Arthropods discovered on refugio flowering plants in Mangifera indica plantation. Biodiversitas 24: 4747-4754. The diversity of Refugio flowering plants with different ways of flowering phenology provides alternative food sources for arthropods. Insects are the largest class of arthropods, most of which are ecological services that function as natural enemies and pollinators. Insects require an energy source over a long-term period to promote a stable and healthy population. The use of flowering plants as refugia can maximize the role of insects as ecological services in agroecosystems by providing natural enemies and pollinators with a source of food and shelter. The refugia plants used in this study were sunflowers (Helianthus annuus), king’s salad (Cosmos caudatus), Peruvian zinnia (Zinnia peruviana), Tridax procumbens (Asteraceae), and Alternanthera sessilis (Amaranthaceae) with hedgerow and insectary bank planting patterns. Data collection and periodic direct observation (scan sampling) were conducted by transects. Observed parameters included species composition and population of arthropods in two different agro-systems, monoculture and polyculture. Identification results showed 8 orders, including 44 morphospecies, belonging to 25 families. Arthropod abundance in the on-season of the refugia was found in 1422 individuals. Ecological engineering is a habitat manipulation technology using refugia plants that has increased the composition and population of natural enemy insects and pollinators.

The role of combination insectary plants and botanical pesticides in increasing arthropod populations of natural enemies and suppressing populations of s. frugiperda in corn

Spodoptera frugiperda is the main pest of corn with a high level of attack intensity. Utilization of natural enemies both predators and parasitoids can be lured using zinnia flowers could be an effective control technique in suppressing armyworm pest populations. Pests hate the smells and taste of botanical insecticides a mixed of maja fruit and giant milkweed leaves which contain secondary metabolites such as volatile, pectin, saponins and tannins. This study aims to determine the effect of zinnia flowers and the application of botanical insecticides in suppressing armyworm populations. This research was carried out in Padakkalawa, Mattirobulu District, Pinrang Regency and Universitas Hasanuddin’s Laboratory of Insect and Plant Disease Relations. The research observed pest intensity, larval population and natural enemies. The results showed that the highest attack intensity was observed in the control treatment with an average of 12.59%/plant. The highest observed larval population was in the control with an average of 2.13 individuals/plant. In observing natural enemy arthropods in all observation techniques, the highest population of natural enemy arthropods was in the combination treatment of zinnia flowers and botanical insecticides with the most species being Lasius niger or ants which was significantly different from the control treatment. The results showed that the combination of insect plants and the application of botanical pesticides had an effect on the population and attack intensity of S. frugiperda larvae and populations of natural enemy arthropods.

Pengaruh Aplikasi Mikroorganisme Lokal terhadap Keanekaragaman Arthropoda pada Tanaman Bawang Merah di Lahan Gambut

This research aims to determine the effect of providing various types of MOL on arthropod diversity in shallot plants in peatlands. This research used a one-factor completely randomized design (CRD), which consisted of four treatments which were repeated five times, so there were 20 experimental units. Each experimental unit consists of 28 plants, so the total number of shallot plants is 560 plants. Treatment consisted of t0: Control, t1: Giving 10 ml MOL leri water, t2: Giving 10 ml MOL leri water+banana stems, t3: Giving 10 ml MOL leri water+fish waste. To determine the diversity of arthropod populations due to MOL administration during observation. Arthropod data resulting from observations or identification are grouped by order and family and presented in tabular form. Next, a diversity analysis was carried out using the species diversity index, species richness, species evenness and dominance. In the observation results, there was no real influence on the diversity of arthropods on shallot plants in peatlands where local microorganisms were applied. The highest diversity of arthropod species was in treatment t2 (1.73), the highest richness of arthropod species was in treatment t1 (2.17), the highest evenness of arthropod species was in treatment t2 (0.94) and the highest dominance was in treatment t0 (0, 25).

Arthropod Diversity in Soybean (Glycine max (L.) MERRILL) with Tagetes erecta

Habitat manipulation aims to conserve insect population on agricultural landscapes by augmenting and conserving the population of natural enemies of pests or biological control agents. The study aimed to evaluate the effect of habitat manipulation on the yield of soybean by assessing the population of insects and other associated arthropods. Companion planting of Tagetes with soybean using inter-row and border row planting designs was followed. A total of 4, 388 individuals representing 11 insect Orders, and 128 species were collected through net sweeping and yellow sticky board traps. These two methods of insect collection were further compared using the two-planting designs. Border row planting design revealed a low population of insect pests, and thus better than the inter-row design. Also, higher number of biological control agents such as coccinellids was found in these plots than in soybean inter-row with Tagetes erecta, and soybean alone.

A nuclear receptor HR96-related gene underlies large trans-driven differences in detoxification gene expression in a generalist herbivore

The role, magnitude, and molecular nature of trans-driven expression variation underlying the upregulation of detoxification genes in pesticide resistant arthropod populations has remained enigmatic. In this study, we performed expression quantitative trait locus (eQTL) mapping (n = 458) between a pesticide resistant and a susceptible strain of the generalist herbivore and crop pest Tetranychus urticae. We found that a single trans eQTL hotspot controlled large differences in the expression of a subset of genes in different detoxification gene families, as well as other genes associated with host plant use. As established by additional genetic approaches including RNAi gene knockdown, a duplicated gene with a nuclear hormone receptor HR96-related ligand-binding domain was identified as causal for the expression differences between strains. The presence of a large family of HR96-related genes in T. urticae may enable modular control of detoxification and host plant use genes, facilitating this species’ known and rapid evolution to diverse pesticides and host plants.

Genetic diversity and gene flow of the soil arthropod (Scolopendra mutilans) in urban landscapes: The roles of rivers, mountains and fragmentation

Abstract Soil invertebrates are a major element of soil biodiversity, which play critical roles in soil ecosystems. However, the impacts of urban landscapes on the genetic diversity and gene flows of soil arthropods remain unclear. Here, we studied the genetic diversity and gene flow of Scolopendra mutilans in an urban area using mitochondrial Cytb genes and eight novel microsatellite loci. A total of 22 haplotypes and 24 variation sites were identified based on 556 bp Cytb sequences from 84 individuals of five populations in Nanjing, Jiangsu Province, China. There were 5.63–8.00 alleles in the average of eight microsatellites found in the S. mutilans arthropod populations, which showed high genetic diversity in urban landscapes. There was no correlation between the natural habitat size and genetic diversity of S. mutilans. The global Fst value based on microsatellites was 0.115, which suggested a medium genetic differentiation and population isolation. The genetic structure of S. mutilans might be affected by urbanisation, as urban patches might hinder gene flow between populations. Ecological corridors preserved in cities might serve as pathways for population migration, which increases gene flow. The gene flows of S. mutilans might not be hindered by natural barriers within cities, as there were strong relationships between populations separated by rivers. These results may contribute to the conservation of S. mutilans diversity and elucidate its adaptation to urbanisation.

Transgenic cotton expressing Mpp51Aa2 does not adversely impact beneficial non-target hemiptera in the field

The modified Mpp51Aa2 (previously Cry51Aa2.834_16) insecticidal crystal protein derived from Bacillus thuringiensis (Bt) protects against feeding damage caused by targeted hemipteran and thysanopteran pests, and was transformed in cotton to produce the MON 88702 cotton event. As part of an ecological risk assessment, we evaluated the relative impact of MON 88702 on the abundance of predatory Hemiptera, compared to a conventional control. Field trials were established in 2018 at six sites within cotton production regions of the U.S. Specific arthropod populations in MON 88702 and its conventional control (DP393), grown under different insecticide regimes within a randomized complete block design, were assessed at each field site. Arthropod samples were collected 10 times, starting at early squaring and weekly thereafter, over the course of the season at each site, using vertical beat sheets, sweep nets and visual counts. Across the sites, no significant differences were detected in abundance of predatory Hemiptera (Orius spp., Geocoris spp., Nabis spp., and Zelus spp.) between unsprayed MON 88702 and the unsprayed conventional control. In contrast, a broad-spectrum insecticide treatment significantly reduced the abundance of these and other taxa. Consistent with laboratory studies, the lack of differences between unsprayed MON 88702 and the unsprayed control indicates that the cultivation of MON 88702 is unlikely to adversely impact the predatory function associated with these beneficial Hemiptera in the cotton agro ecosystem.

Estimation and analysis of insect population dynamics parameters via physiologically based models and hybrid genetic algorithm MCMC methods

Decision support systems are gaining importance in several fields of agriculture, forest, and ecological systems management. Their predictive potential, entrusted to mathematical models, is of fundamental importance to set up opportune strategies to control pests and adversities that may occur and that may seriously compromise the natural equilibria. Among the others, population dynamics is one of the crucial challenges in the field. Despite the scientific community in recent years providing valuable models that faithfully represent terrestrial arthropods populations, such as insects, one of the main concerns is still represented by the parameter estimation. Parameters, in fact, characterise the species and their estimation are often entrusted to dedicated laboratory experiments that require specific equipment and highly qualified personnel. In this study we propose a novel method to estimate the model parameters directly from field data, where experimental activities are less expensive and less time consuming. In this study we propose a combination of least squares methods via genetic algorithms to preliminary evaluate the best parameter values and Markov Chain Monte Carlo approach to obtain their distribution. The algorithm has been tested in the special case of Drosophila suzukii, to quantify part of the parameters of an almost validated model in two steps: i) a first pseudo-validation using perturbed numerical solutions, and ii) a validation using real field data. The results highlighted the potentialities of the algorithm in estimating model parameters and opened several perspectives for further improvements from both the computational and experimental point of view.

Mapping the poultry insectome in and around broiler breeder pullet farms identifies new potential Dipteran vectors of Histomonas meleagridis

BackgroundHistomonas meleagridis can infect chickens and turkeys. It uses the eggs of the cecal worm Heterakis gallinarum as a vector and reservoir. Litter beetles (Alphitobius diaperinus) and other arthropod species have been implicated as potential vectors, but little information about other arthropod species as potential vectors is known.MethodsFour broiler breeder pullet farms were sampled every 4 months. On each farm, three types of traps were set inside and outside two houses. Trapped arthropod specimens were morphologically identified at order level and grouped into families/types when possible. Selected specimens from abundant types found both inside and outside barns were screened for H. meleagridis and H. gallinarum by qPCR.ResultsA total of 4743 arthropod specimens were trapped. The three most frequently encountered orders were Diptera (38%), Coleoptera (17%), and Hymenoptera (7%). Three hundred seventeen discrete types were differentiated. More arthropods were trapped outside than inside. Alpha diversity was greater outside than inside but not significantly influenced by season. The composition of the arthropod populations, including the insectome, varied significantly between trap location and seasons. Up to 50% of litter beetles tested positive for H. meleagridis DNA 4 months after an observed histomonosis outbreak. Sporadically litter beetles were positive for H. gallinarum DNA. Thirteen further arthropod types were tested, and specimens of four Dipteran families tested positive for either one or both parasites.ConclusionsThis study describes the insectome in and around broiler breeder pullet farms and identifies new potential vectors of H. meleagridis through qPCR. The results show a limited but present potential of arthropods, especially flies, to transmit histomonosis between farms.Graphical

Reduced male fertility of an Antarctic mite following extreme heat stress could prompt localized population declines.

Climate change is leading to substantial global thermal changes, which are particularly pronounced in polar regions. Therefore, it is important to examine the impact of heat stress on the reproduction ofpolar terrestrial arthropods, specifically, how brief extreme events may alter survival. We observed that sublethal heat stress reduces male fecundity in an Antarctic mite, yielding females that produced fewer viable eggs. Females and males collected from microhabitats with high temperatures showed a similar reduction in fertility. This impact is temporary, as indicated by recovery of male fecundity following return to cooler, stable conditions. The diminished fecundity is likely due to a drastic reduction in the expression of male-associated factors that occur in tandem with a substantial increase in the expression of heat shock proteins. Cross-mating between mites from different sites confirmed that heat-exposed populations have impaired male fertility. However, the negative impacts are transient as the effect on fertility declines with recovery time under less stressful conditions. Modeling indicated that heat stress is likely to reduce population growth and that short bouts of non-lethal heat stress could have substantial reproductive effects on local populations of Antarctic arthropods.

The analysis of the influence of grazing intensity on the diversity and abundance of plants and spiders (Arachnida: Araneae)

In restoration projects, low stock grazing has become a popular means of management. However, an accurate understanding of the effects of grazing on plants and spiders is often lacking. Although spiders and plants are not closely related evolutionarily or genetically, the relationship between them can be complex and diverse. Many species of spider build their webs or nests on plants, using the leaves, stems, or flowers as anchoring points. This provides them with protection from predators, access to prey and a stable habitat. On the other hand, spiders can provide a number of benefits to grassland ecosystems, such as helping to control populations of insects and other arthropods that can damage or consume grassland plants. This study addresses the effects of different grazing regimes on plant and spider diversity in siliceous grasslands. Plant and spider diversity was studied for four months in the Sharri Mountains (Kosovo) in order to determine the biodiversity in ungrazed, moderately grazed and overgrazed siliceuous grasslands. The responses of plant height, plant biomass, plant species diversity and spider species diversity to three grazing intensities at 12 sites were recorded. Vegetation structure (plant height and plant biomass) was significantly higher in ungrazed grasslands compared to grazed and overgrazed grasslands. This was not the case, however, for spider species richness and diversity, as these were higher in moderately grazed than ungrazed grassland. On overgrazed grasslands, spider diversity was extremely low, as only one species of spider (Pardosa saltuaria) was recorded. Plant and spider diversity increased in the following order: overgrazed grasslands < ungrazed grasslands < moderately grazed grasslands, in all the habitats studied. Different grazing intensities significantly affected the abundance of particular plants on siliceous grasslands, for example, Deschampsia cespitosa, one of the most dominant plants on siliceous grasslands had an abundance of 4.77% in ungrazed grasslands., but only 4.94% in moderately grazed grasslands and was absent in overgrazed grasslands. There were other species of plants that were most abundant in intensively grazed silicate grasslands. One of them was Nardus stricta, whose percentage in ungrazed, moderately grazed and overgrazed grasslands was characterized by a multiple exponential increase in % (s1 – ungrazed grasslands = 0.99%, s2 – moderately grazed grasslands = 1.25% and s3 – overgrazed grasslands = 10.50%). It is concluded that the intensity of grazing of natural grasslands directly affects biodiversity and that this information may be valuable for long-term management and conservation programs in similar habitats in SE Europe and beyond.