Arthropod-Plant Interactions最新文献

Pointed gourd (Trichosanthes dioica Roxb.) is an economically important dioecious vegetable crop having separate plants growing male and female flowers. Cross-pollination is imperative for its fruit settings and insects play a pivotal role in this. Although a nitidulid beetle was reported to be a primary pollinator in pointed gourd, its species identification and validation were needed to enhance the fruit production. The beetles collected from the pointed gourd have revealed presence of abundant round or spheroidal, trizonopororate, sticky pointed gourd pollens. Further, role of beetle was validated in farmers field where no fruit set was recorded when beetle’s visit was curtailed. Twenty adult beetles were artificially released into a caged pot, and the maximum fruit setting (30.43%) indicated its potential role in pointed gourd pollination in vegetable ecosystem. Beetle-pollinated fruits had higher fruit length (6.88 cm), width (2.83 cm), fruit weight (22.63 g), and lesser number of seeds (16.75) than the hand-pollinated fruits (6.21 cm, 2.77 cm, 19.41 g, and 21.75 numbers, respectively). The morphological and molecular analysis identified the species as Epuraea motschulskyi and the study hereby reports for the first time that E. motschulskyi is the primary pollinator in pointed gourd. The study also suggests that the release and protection of the beetle in pointed gourd field would lead to enhanced fruit set.

Tribolium castaneum is a significant pest in grain storage, causing considerable economic impact globally. Plant-derived insecticides are being employed as alternatives to chemical insecticides and have shown strong insecticidal activity against T. castaneum. However, the mechanism underlying the insecticidal effects of plant-derived insecticides on T. castaneum remains unclear. In this study, we investigated the repellent, fumigation, and contact activities of R. anthopogonoides essential oil (EO) and its four main chemical components against T. castaneum. The results demonstrated that both the EO and its main chemical component, benzylacetone, exhibited potent insecticidal activity against T. castaneum. Benzylacetone may be the primary active component of R. anthopogonoides EO against T. castaneum. Subsequently, transcriptome sequencing of T. castaneum treated with Benzylacetone, along with negative controls, revealed 1616 differentially expressed genes (DEGs), with 758 up-regulated and 858 down-regulated genes. GO analysis indicated that the DEGs were mainly enriched in “cellular process,” “metabolic process,” “cell,” “cell part,” “catalytic activity,” “binding,” and other categories. KEGG pathway analysis revealed that the 417 DEGs were distributed across 217 different pathways, with several pathways related to xenobiotic or drug metabolism significantly enriched. This suggests that Benzylacetone likely disrupts metabolic and detoxication processes. Additionally, qRT-PCR validation of the TcOBP-4E and TcCYP450-6BK11 genes exhibited consistent results with the transcriptome data. Homology modeling and molecular docking results indicated the presence of a binding cavity formed by numerous hydrophobic amino acid residues in TcOBPs, with possible hydrogen bonds and hydrophobic interaction forces between the protein and ligand. These findings suggest that OBP and CYP450 play crucial roles in the resistance to foreign substances and provide a theoretical basis for understanding the insecticidal mechanisms of plant-derived insecticides at the molecular level.

The study examined the kin-recognition ability in the third and fourth instars of two predatory ladybirds, Hippodamia variegata (Goeze) and Menochilus sexmaculatus (Fabricius), by investigating the impact of relatedness, food quality and hunger on the avoidance of kin-cannibalism. Higher instars of both species cannibalized more non-relative first instars than the relative ones, suggesting that they can distinguish kin and abstain from cannibalizing them. The frequency of cannibalism among these larvae increased when victims were fed on dissimilar and unsuitable diets compared to those fed on the same diet as the cannibals. Cannibalistic tendencies were delayed when victims were fed on the same and appropriate diet. Fourth instars of both species had greater encounters with victims whose diets differed. Hungrier larvae of both species had more encounters and incidences of cannibalism with a shorter latency period than their satiated counterparts. It is inferred that hunger, lack of access to natural food, and challenges during molting or pupation instigate ladybird instars to engage in cannibalism. Nevertheless, when relatives are presented as food, the frequency of larval cannibalism decreases. The rate of cannibalism was higher in M. sexmaculatus compared to H. variegata, as the former is a more aggressive predator.

The paper investigates the distributions of legumes (Fabaceae) and their associated seed beetle species (Bruchinae) across vegetation zones and regions of Europe and evaluates the host range and specialization of seed beetles. 1584 legume species/subspecies/varieties were included in the study and ca. 16% of these serve as known hosts by the 175 seed beetle species found in Europe. Both plant and seed beetle species richness increased from the Boreal to Mediterranean zones/regions. 717 legume species occurred only in single zones/regions and only 4.7% of these (34 species) were hosts for 38 bruchine species specific to a zone/region. Europe has 664 native legume species and 381 of these are Eu-endemics. There were 52 alien legume species found. Similarities in plant species composition by the Sørensen index were pronounced between the Central-European and the Mediterranean, between the Transcaucasian and Mediterranean, and between the Colchis-Caucasian and the Pontic-Caspian areas. The most species-rich genus is Astragalus L. with 334 species and 16 subspecies. Of the two major pre-dispersal seed predator genera, Bruchidius Schilsky species are sensu lato oligophagous, using a wide range of leguminous tribes as hosts, but restricted to few host species within a tribe. In contrast, members of the Bruchus L. genus are sensu stricto oligophagous species and, despite being constrained to the Fabeae tribe, most of them feed on several Lathyrus L. and Vicia L. species. The ways annual and perennial life cycles as well as chemical constituents of legumes might affect the colonization success of the seed beetles are discussed.

Intercrops are a potential crop management practice for reducing pest populations and improving the biodiversity of arthropods. The impact of intercropping onion (Allium cepa L.) and safflower (Carthamus tinctorius L.) was investigated on tritrophic interactions of onion- Thrips tabaci Lind.—predators in 2022 and 2023 in Iran. The experiments were accomplished in a randomized complete block design with treatments of intercropping onion (O) and safflower (S) in three patterns of row alternation: 4O:2S, 4O:4S, and 4O:8S along with the sole cropping of onion and safflower. The three intercropping systems reduced the densities of larvae and adults of onion thrips compared with the onion sole cropping over the two growing seasons. Besides, the leaf damage index per plant decreased in the intercropping systems compared to the onion sole cropping, reaching the lowest value in 4O:4S and 4O:8S in two years. The total abundance of onion plant- or ground-dwelling predators was higher in intercrops than in the sole crop. Further, higher Shannon diversity indices for onion plant-dwelling predators (H′ ≥ 1.73) and ground-dwelling predators (H′ ≥ 1.30) were recorded in intercrops, especially 4O:4S and 4O:8S. The land equivalent ratio (LER) ranged from 1.26 for 4O:2S in 2023 to 1.32 for 4O:4S in 2022. Our conclusions showed that intercropping onion-safflower, especially in the patterns of 4O:4S and 4O:8S, promoted the biocontrol service of onion thrips and crop production compared with the sole crops. Therefore, 4O:4S and 4P:8S intercrops are effective practices for controlling onion thrips in fields.

The carnivorous habit has been interpreted as an outstanding adaptation that let some plants the acquisition of mineral nutrients in habitats characterized by a chronic scarcity of nutrients. Substantial evidence indicates how carnivorous plants benefit from its interaction with prey. However, fitness of carnivorous plants depends not only on the interaction with their prey but on other interactions such as pollination, herbivory, and kleptobiosis. It is also known that evolutionary ecology of carnivorous plants is regulated by the cost–benefit ratio that is imposed majorly by the abiotic environment limiting photosynthesis. We analyzed how these three little explored interactions in carnivorous plants could promote scenarios rising additional costs to those that are hypothesized to occur linked to the evolution of botanic carnivory. In specific, we (i) explained a general ecological context of each interaction, (ii) reviewed how the interactions increase costs in carnivorous plants, (iii) identified factors that regulate the negative effect on carnivorous plants, and (iv) identified lines for future research.

Palm trees (Arecaceae) are among the most important plants in the world, providing food and subsistence for various populations, especially in the Amazon region. Many of these trees depend on pollinators to produce fruits. In this study, we evaluated the pollination service values in 13 palm crops in the Brazilian Legal Amazon based on the agricultural production values of each species and their dependencies on pollinators, and we compared the values between forested and non-forested areas. We also aimed to review the scientific literature to present the most important pollinator species of those same palm crops. The total production value of the palms was estimated at US$239.9 million/year (2017), and 85% of this value was associated with the açaí fruit (Euterpe oleracea). The municipalities that had the highest production values were in the State of Pará (79.5%), considered the largest açaí producer in Brazil. The second most important crop was babassu (Attalea speciosa), with its production concentrated mainly in the State of Maranhão. Pollination services were valued at US$144.2 million/year, with açaí cultivation corresponding to 92% of this value. The forested areas were responsible for 86.4% of the total production value, with a pollination service value of US$127 million/year. The main pollinators reported were insects of the orders Hymenoptera (Apidae) and Coleoptera (especially Curculionidae). The results obtained in this study highlight the importance of pollinators to produce fruits and seeds in palm crops and reinforce the need to conserve both the pollinators and the forest, to ensure food security and the sustainable development of the region.

Citizen science is an increasingly powerful tool to gather large quantities of biological data and to engage the public. The number of citizen science initiatives has rapidly increased in the last 15 years. Invasive alien species such as the harlequin ladybird, Harmonia axyridis (Coleoptera, Coccinellidae), provide a particularly good opportunity for broad-scale use of such initiatives. Harmonia axyridis is parasitized by a fungus, Hesperomyces harmoniae (Ascomycota, Laboulbeniales), that can be found throughout the range of its host. Here we present Beetlehangers.org, a website and data repository where we combine observations of He. harmoniae from literature, online databases, and citizen science initiatives, including new records of both Ha. axyridis and He. harmoniae. Whereas Ha. axyridis is now present in 86 countries across six continents (including seven new country records), the distribution of its parasite He. harmoniae comprises 33 countries in five continents (including two new country records since its description in 2022). We explore spatiotemporal trends of He. harmoniae in light of these records. Finally, we discuss challenges and new opportunities for citizen science in relation to species interactions such as these and provide future perspectives for the website as a home for future Laboulbeniales research and outreach.

Between 2016 and 2022, the ladybird (Coleoptera: Coccinellidae) fauna was surveyed on seven main islands of the Canary Islands archipelago. Adult specimens were collected and screened for thalli of Laboulbeniales (Ascomycota: Laboulbeniomycetes). Altogether, 9,807 ladybird specimens belonging to 39 species were screened, of which 103, representing 10 species, were infected by Laboulbeniales of the genus Hesperomyces. Morphological and molecular examination allowed to distinguish at least seven host-specific Hesperomyces species belonging to three groups: He. virescens species complex (associated with Adalia decempunctata, Harmonia axyridis, Hyperaspis vinciguerrae, Novius cruentatus, Parexochomus nigripennis, and P. quadriplagiatus), He. coccinelloides species complex (Scymnus nubilus, Sc. subvillosus durantae, and Stethorus tenerifensis), and a species (on Nephus flavopictus) that cannot be assigned to either of the above species complexes or the currently described species in the genus. The most widespread and abundant species was Hesperomyces ex St. tenerifensis; it was recorded on all seven islands with prevalence rates ranging between 0.04 and 0.19.

The tomato leaf miner (TLM), Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is one of the most important and destructive pests of tomatoes and is threatening worldwide tomato production. While control of this pest insect is primarily based on conventional synthetic pesticides, there is a growing concern to use more ecologically sound pest management strategies, e.g., the use of soil microorganisms. In this project, we therefore investigated the effect of a mixture of four species of arbuscular mycorrhizal fungi (AMF) (Funneliformis mosseae, Rhizophagus intraradices, R. irregularis, and Glomus iranicus) when inoculated with tomato plants in relation to the induction of defense in the plant leaves, and also the potential to resist against TLM. For all three plant enzymes investigated, peroxidase, phenylalanine ammonia lyase, and polyphenol oxidase, the inoculation with AMF had induced an increase, and also the total phenol contents in AMF-plants were higher. When AMF-plants were infected with TLM, this caused higher increases. In parallel, the life table parameters of TMF feeding on AMF-plants demonstrated that the insects were retarded in development and reproduction potential, e.g., a lower intrinsic rate of increase (r_m), net reproduction rate (R₀), and fecundity and a shorter oviposition period. These findings do not only provide insights in the synergy between AMF and tomato plants, but are also useful for developing more ecologically sound pest management strategies against this important pest insect of TLM and potentially also other pest in the future.