The greater wax moth,
Galleria mellonella
, is a global pest for beehives, doing damage in the larval stage. Although a significant number of studies have reported on larvae and adults, to date no ...effective pest control has been implemented. In this study, we tested larval resistance to alkaloids from
Berberis microphylla
, and the objective was to identify enzymes that participate in alkaloid detoxification through enzymatic assays, bioinformatics analysis and qRT-PCR. Findings suggest glutathione-S-transferases (GSTs), from an increased metabolic mechanism, are responsible for alkaloid detoxification rather than cytochrome P450 (CYP), carboxylesterases (CarE). A bioinformatics analysis from transcriptome data revealed 22 GSTs present in both
G. mellonella
larvae and adults. The qRT-PCR experiments corroborated the presence of the 22 GSTs in larvae, where GST8 and GST20 stood out with the highest expression after berberine treatment. Structural information around GST8 and GST20 suggests that GST8 could bind berberine stronger than GST20. These findings represent an important advance in the study of detoxification enzymes in
G. mellonella
, expanding the role of delta-class GSTs towards alkaloids. Likewise, GST inhibition by alkaloid analogs is proposed in the framework of integrated pest management strategies.
The relationship between phosphorus (P) availability and water restriction was explored in this study, focusing on its impact on phosphorus use efficiency (PUE) and water use efficiency (WUE) in ...various bromegrass (Bromus spp.) genotypes. Under controlled conditions, five bromegrass genotypes, as well as one ryegrass (Lolium perenne) cultivar, were compared by subjecting them to two P levels and two watering regimes. It was determined that combining water and phosphorus limitations led to reduced plant productivity. Initially, the ryegrass outperformed the bromegrass, but this result declined over time, while bromegrass exhibited consistent stability. Notably, under P and water stress, enhanced root development was observed in bromegrass compared to that in ryegrass. Distinct patterns of PUE and WUE allowed for the categorization of bromegrass genotypes into three groups. Genotype 3457 emerged as the most efficient, scoring 20 out of 24, while Pro 94-49 A achieved a score of only 10 out of 24. This study suggests that the drought resilience of bromegrass may be linked to increased root growth during the early vegetative stages, which potentially facilitates improved P acquisition. However, further validation through long-term field experiments is needed. The insights from this study are potentially valuable for use in shaping plant breeding programs by revealing the plant adaptation mechanisms for both P and water absorption.
The foraging behavior of the infective juveniles (IJs) of entomopathogenic nematodes (EPNs) relies on host-derived compounds, but in a tri-trophic context, herbivore-induced root volatiles act as ...signals enhancing the biological control of insect pests by recruiting EPNs. In southern Chile, the EPN
exhibits the potential to control the raspberry weevil,
a key pest of blueberry
. However, there is no information on the quality of the blueberry root volatile plume or the
response to these chemicals as putative attractants. Here, we describe the root volatile profile of blueberries and the chemotaxis behavior of
towards the volatiles identified from
roots, infested or uninfested with
larvae. Among others, we found linalool, α-terpineol, limonene, eucalyptol, 2-carene, 1-nonine, 10-undecyn-1-ol, and methyl salicylate in root volatiles and, depending on the level of the emissions, they were selected for bioassays. In the dose-response tests,
was attracted to all five tested concentrations of methyl salicylate, 1-nonine, α-terpineol, and 2-carene, as well as to 100 µg mL
of 10-undecyn-1-ol, 0.1 and 100 µg mL
of linalool, and 100 µg mL
of limonene, whereas eucalyptol elicited no attraction or repellency. These results suggest that some volatiles released from damaged roots attract
and may have implications for the biocontrol of subterranean pests.
The European grapevine moth, Lobesia botrana (Denis & Schiffermüller), is a serious pest in vineyards in North and South America. Mating disruption techniques have been used to control and monitor L. ...botrana on the basis of its sexual communication. This needs a well‐tuned olfactory system, in which it is believed that pheromone‐binding proteins (PBPs) are key players that transport pheromones in the antennae of moths. In this study, the selectivity of a PBP, named as LbotPBP1, was tested by fluorescence binding assays against 11 sex pheromone components and 6 host plant volatiles. In addition, its binding mechanism was predicted on the basis of structural analyses by molecular docking and complex and steered molecular dynamics (SMD). Our results indicate that LbotPBP1 binds selectively to sex pheromone components over certain host plant volatiles, according to both in vitro and in silico tests. Thus, chain length (14 carbon atoms) and functional groups (i.e., alcohol and ester) appear to be key features for stable binding. Likewise, residues such as Phe12, Phe36, and Phe118 could participate in unspecific binding processes, whilst Ser9, Ser56, and Trp114 could participate in the specific recognition and stabilization of sex pheromones instead of host plant volatiles. Moreover, our SMD approach supported 11‐dodecenyl acetate as the best ligand for LbotPBP1. Overall, the dynamics simulations, contact frequency analysis and SMD shed light on the binding mechanism of LbotPBP1 and could overcome the imprecision of molecular docking, supporting the in vitro binding assays. Finally, the role of LbotPBP1 in the chemical ecology of L. botrana is discussed.
LbotPBP1 binds selectively to sex pheromone components over certain host plant volatiles, according to both in vitro and in silico tests.
The entomopathogenic nematode (EPN) Steinernema australe was isolated from Isla Santa Magdalena in Chile and identified as a good alternative for controlling Aegorhinus nodipennis (Coleoptera: ...Curculionidae) larvae. This weevil is native to the south of Chile and some regions in Argentina, causing the decline and ultimate death of plants in berry orchards. The major problem brought about by the weevil is caused by the larvae, which spend between nine and eleven months below ground, feeding inside the roots of the plants. This study seeks to increase S. australe’s efficacy through an artificial selection process using an odor stimulus. We selected infective juveniles (IJs) that followed the stimulus in order to reach larvae at a depth of 30 cm to achieve this objective. Larvae infected with selected IJs and IJs from the original stock were compared under laboratory, greenhouse, and field conditions. The results showed a 20% increase in the efficacy of selected IJs compared with IJs from the original stock. We observed a higher proportion of selected IJs that reached the larvae faster during the first four days post-application. Moreover, larvae treated with selected IJs were depleted, with a mix of nematode stages emerging from the cadaver. Finally, a potential trade-off with regard to the recycling of nematodes into the soil is proposed.
The phosphorus (P) addition can be helpful in the mitigation of the adverse effects of water deficit stress. However, the efficiency of wheat in utilizing both components has not been assessed in ...field conditions. This research aims to assess the effects of P and water addition on phosphorus use efficiency (PUE) and water productivity (WP) in field conditions for select wheat cultivars co-adapted to climate-induced agronomic challenges. Three wheat cultivars were selected based on their PUE and water WP from a previous experiment. The trials were conducted in field conditions over two consecutive years, from 2020 to 2021 (Season 1) and 2021–2022 (Season 2). The plants were grown on an andisol with a soil P concentration of 10 mg P kg−1 and 30 mg P kg−1. Two irrigation treatments were imposed: Well-watered (+W) and dryland (-W). The plants were sampled at three stages: tillering (Z25), anthesis (Z65), and ripening (Z95). At the end of the phenological cycle, grain yield components, grain yield, grain quality, PUE, and WP were evaluated. Phosphorus addition promotes plant growth, especially in the early vegetative stages, by enhancing tiller development and nutrient and water uptake. These effects were critical during the anthesis and ripening stages, enhancing yield components and higher grain production. Differential responses were observed across cultivars, underscoring the genotype-specificity in PUE and WP. Seasonal water deficit stress modulated these effects, highlighting a more complex genotype-environment-nutrient interaction. The water addition promoted PUE and WP, suggesting a synergy between the two components. Among the cultivars, Chevignon outperformed in grain yield, PUE, and WP. However, while phosphorus, water, and environmental factors influenced grain quality, the genetic background of the cultivar was the primary determinant of these components. This study advocates for implementing individual nutrient management strategies tailored to the specific cultivar and adaptable to environmental conditions under climate change.
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•Phosphorus boosts wheat growth by 30% under dryland conditions.•Phosphorus enhances gluten and protein content in wheat under dryland conditions.•Phosphorus use efficiency (PUE) varies across phenological stages and wheat cultivars.•The genetic background of cultivars predominantly determines wheat grain protein and gluten composition.
Chemoreception through odorant receptors (ORs), ionotropic receptors (IRs) and gustatory receptors (GRs) represents the functions of key proteins in the chemical ecology of insects. Recent studies ...have identified chemoreceptors in coleopterans, facilitating the evolutionary analysis of not only ORs but also IRs and GRs. Thus, Cerambycidae, Tenebrionidae and Curculionidae have received increased attention. However, knowledge of the chemoreceptors from Scarabaeidae is still limited, particularly for those that are sympatric. Considering the roles of chemoreceptors, this analysis could shed light on evolutionary processes in the context of sympatry. Therefore, the aim of this study was to identify and compare the repertoires of ORs, GRs and IRs between two sympatric scarab beetles, Hylamorpha elegans and Brachysternus prasinus. Here, construction of the antennal transcriptomes of both scarab beetle species and analyses of their phylogeny, molecular evolution and relative expression were performed. Thus, 119 new candidate chemoreceptors were identified for the first time, including 17 transcripts for B. prasinus (1 GR, 3 IRs and 13 ORs) and 102 for H. elegans (22 GRs, 14 IRs and 66 ORs). Orthologs between the two scarab beetle species were found, revealing specific expansions as well as absence in some clades. Purifying selection appears to have occurred on H. elegans and B. prasinus ORs. Further efforts will be focused on target identification to characterize kairomone and/or pheromone receptors.
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•RNA-seq from two sympatric scarab beetles reveals 119 new candidate chemoreceptors for the first time.•The oligophagous Hylamorpha elegans has six times the amount of chemoreceptors than the monophagous, Brachysternus prasinus.•Orthologues between both scarab beetles show specific Scarabaeidae expansions.•Purifying selection was found to be acting on particular OR lineages of H. elegans and B. prasinus.
The current scientific evidence shows a synergistic role between phosphorus use efficiency (PUE) and water use efficiency (WUE). However, the interactions between plants and soil microorganisms that ...stimulate phosphorus (P) and water uptake could exhibit variation at the cultivar level. This manuscript aims to evaluate the influence of different wheat cultivars on soil microbial activities and functional diversity and how their interaction could affect plant performance in terms of PUE and WUE.
Three wheat cultivars (Fritz, Chevignon, and Rancofén) differing in their ability to use P and water were grown under controlled conditions on an Andisol with background soil P-concentration of 4 mg P kg−1 (-P), which was enriched to 30 mg P kg−1 (+P). Water management was applied at two levels: well-watered (+W) and 30% of the water applied to + W (water stress, -W). Soil microbial activities were assayed at the anthesis stage, but wheat was harvested at the end of its phenological cycle.
Phosphorus scarcity and water deficit stress negatively affected growth traits, P acquisition, and grain yield of wheat cultivars. The P concentration affected the acid phosphatase (APs) and dehydrogenase activity (DHA) more than water management.
The community-level physiological profile (CLPP) was modulated by the cultivar, water management, and P concentration. The main drivers determining microorganisms' catabolic activity were water deficit stress and high P concentration in the soil. The P addition to plants facing water limitation increased by about 84% the CO2 production by soil microorganisms.
Finally, the differences observed among cultivars and the soil microbial activities affected PUE and WUE performance, being Fritz the most efficient cultivar in both components in all conditions evaluated.
Our data suggest that an assembly between cultivars and microorganisms affects the plant performance in terms of PUE and WUE.
•Phosphorus (P) and water deficit affected wheat cultivars regarding growth traits, P acquisition, and grain yield.•The main drivers affecting microorganisms' activity were the water deficit stress and high soil P content.•An assembly between cultivars and microorganisms affects the plant's performance in terms of PUE and WUE.
The foraging behavior of the infective juveniles (IJs) of entomopathogenic nematodes (EPNs) relies on host-derived compounds, but in a tri-trophic context, herbivore-induced root volatiles act as ...signals enhancing the biological control of insect pests by recruiting EPNs. In southern Chile, the EPN Steinernema australe exhibits the potential to control the raspberry weevil, Aegorhinus superciliosus, a key pest of blueberry Vaccinium corymbosum. However, there is no information on the quality of the blueberry root volatile plume or the S. australe response to these chemicals as putative attractants. Here, we describe the root volatile profile of blueberries and the chemotaxis behavior of S. australe towards the volatiles identified from Vaccinium corymbosum roots, infested or uninfested with A. superciliosus larvae. Among others, we found linalool, α-terpineol, limonene, eucalyptol, 2-carene, 1-nonine, 10-undecyn-1-ol, and methyl salicylate in root volatiles and, depending on the level of the emissions, they were selected for bioassays. In the dose–response tests, S. australe was attracted to all five tested concentrations of methyl salicylate, 1-nonine, α-terpineol, and 2-carene, as well as to 100 µg mLsup.−1 of 10-undecyn-1-ol, 0.1 and 100 µg mLsup.−1 of linalool, and 100 µg mLsup.−1 of limonene, whereas eucalyptol elicited no attraction or repellency. These results suggest that some volatiles released from damaged roots attract S. australe and may have implications for the biocontrol of subterranean pests.
Host plant recognition are highly dependent on chemosensory perception, which involves chemosensory proteins (CSPs) that bind key chemical compounds the host plants. In this work, we hypothesize that ...two closely related aphid taxa, which differ in diet breadth, also differ in their CSPs. We detected a non-synonymous difference (lysine for asparagine) between M. persicae sensu stricto (Mpp) and the subspecies M. p. nicotianae (Mpn) in the sequence of a CSP (CSP5). We modeled in silico the binding capacity of both CSP5s variants with 163 different potential ligands from their host plants (120 unique from tobacco, 29 unique from peach, and 14 common ligands). After docking analysis with all ligands, we selected the three best ligands for each variant to perform molecular dynamics (tobacco: 2-cyclopentene-1,4-dione, salicylaldehyde, and benzoic acid; peach: phenol, valeric acid, and benzonitrile). The binding energy of the MpnCSP5 model to the studied ligands was, in all cases, lower than with the MppCSP5 model. The ligands from the host plants showed more stable binding with MpnCSP5 than with MppCSP5. This result suggests that the set of CSPs studied among M. persicae s. str. and M. p. nicotianae are very similar, but focusing on the CSP5 protein, we found a single key mutation that increases affinities for host compounds for M. p. nicotianae, which might have contributed to the specialization to tobacco. This study provides new insights into an evolutionary trend toward specificity in a binding protein.
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•A mutation in an insect's chemosensory protein changes the affinity for plant chemicals.•The mutation increased the binding to ligands in the specialized insect protein.•The mutation did not occur at the active site, but 10 Å away from it.
