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Artigo
Association of non-host crop plants with mandarin in host location and survival of Diaphorina citri Kuwayama (Hemiptera: Psyllidae)
(2023-12-13) Pec, Marvin; Ferreira, Ester Alice; Peñaflor, Maria Fernanda G. V.
Research efforts have been made to develop novel tactics, such as those targeting behavioral control, for management of the Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Psyllidae), vector of the causal agent of citrus Huanglongbing. Here, we investigated whether association of “Ponkan” mandarin (Citrus reticulata) with volatiles from non-host crops: avocado, passion fruit or coffee, alters host location by the Asian citrus psyllid; and whether they can be temporary hosts for the Asian citrus psyllid. In wind tunnel assays, we found that the association of mandarin seedling with avocado plant volatiles reduced in 30% the number of psyllids sitting on host plants compared to the mandarin alone. In contrast, passion fruit plant volatiles facilitated host location by psyllids, which found mandarin seedlings faster than when exposed to mandarin alone. The association with coffee volatiles did not alter the attractiveness of mandarin to the Asian citrus psyllid. Survival and half-lethal time (LT50) of D. citri fed on non-host plants were longer than those insects with water only, but shorter than those fed on mandarin. Among the non-host plants, D. citri performed better in coffee, followed by avocado and passion fruit plants. Our results indicate that the association of mandarin with avocado plant can be beneficial for Asian citrus psyllid management.
Artigo
Assessing troglomorphic and phylogenetically informative traits in troglobionts: a new cave-dwelling centipede illuminates the evolution of a soil-dwelling lineage (Chilopoda: Geophilidae)
(2023-08-04) Bonato, Lucio; Ferreira, Rodrigo Lopes
Cave-dwelling species are of special interest in evolutionary biology, because (i) many share particular traits associated with the cave habitat (troglomorphic traits), and (ii) some represent relict lineages that may conserve ancestral traits or possibly transitional traits, which may provide insights into the evolution of other highly derived species. However, these different kinds of characters are hard to assess thoroughly in troglobionts belonging to little known terrestrial arthropod groups. We describe a new species of centipedes from the Areias System caves, Brazil, namely, Plutogeophilus jurupariquibaba gen.n. sp.n., which adds to the few putative troglobionts known among Chilopoda Geophilomorpha. We analyzed a suite of characters in the light of a phylogenetic analysis and by direct comparison with epigean relatives, controlling for interindividual variation and its confounding sources. We found that: (i) troglomorphic traits of P. jurupariquibaba may include large body, elongate antennae, elongate legs and claws, and possibly also elongate setae and large coxal pores; (ii) the cave-dwelling Plutogeophilus is the sister lineage of the soil-dwelling Macronicophilus, whose morphology is highly derived and whose phylogenetic position remained unclear; (iii) compared with other extant geophilids, symplesiomorphic traits and apparently intermediate traits found in Plutogeophilus provide insights on the origin of the morphology of Macronicophilus, suggesting a stepwise modification of labrum, forcipular apparatus and ultimate legs, and the derivation of the unique rounded and spiny tip of the second maxillae from a pointed claw.
Artigo
Assessing the therapeutic and toxicological profile of novel acetylcholinesterase reactivators: value of in silico and in vitro data.
(2023-01-20) Ramalho, Teodorico C.; Castro, Alexandre A. de; Leal, Daniel Henriques Soares; Teixeira, Jéssika Poliana; Cunha, Elaine F. F. da; Kuča, Kamil
Organophosphorus compounds (OP) make up an important class of inhibitors, mostly employed as pesticides, even as chemical weapons. These toxic substances act through the inhibition of the acetylcholinesterase (AChE) enzyme, which results in elevated synaptic acetylcholine (ACh) levels, leading to serious adverse effects under the cholinergic syndrome. Many reactivators have been developed to combat the toxic effects of these AChE inhibitors. In this line, the oximes highlight because of their good reactivating power of cholinesterase enzymes. To date, no universal antidotes can reactivate AChE inhibited by any OP agent. This review summarizes the intoxication process by neurotoxic OP agents, along with the development of reactivators capable of reversing their effects, approaching aspects like the therapeutic and toxicological profile of these antidotes. Computational methods and conscious in vitro studies, capable of significantly predicting the toxicological profile of these drug candidates, might support the process of development of these reactivators before entering in vivo studies in animals, and then clinical trials. These approaches can assist in the design of safer and more effective molecules, reducing related cost and time for the process.
Artigo
Assessing the functional diversity of rhizobacteria from cacao by partitioning root and shoot biomasses
(2023-05-31) Loguercio, Leandro Lopes; Silva, Augusto César Moura; Ribeiro, Daniel Henrique; Cruz, José Manoel Ferreira de Lima; Soares, Ana Cristina Fermino; Marbach, Phellippe Arthur Santos; Cruz-Magalhães, Valter; Souza, Jorge Teodoro de
Plant–microbe interactions are critical for the sustainability of agricultural production. In this study, our aims were to characterize the genetic and functional diversity of the culturable bacterial community associated with the cacao rhizosphere and access their potential for growth promotion of cacao seedling. Culture-dependent and molecular methods were used to characterize the population densities and diversity of bacterial communities from soil and cacao plants at two locations and two plant ages. A total of 63 strains were identified through hsp60 sequencing. Pseudomonas and Enterobacter were the most abundant genera in association with the cacao rhizosphere, whereas Bacillus was more numerous in soil. Parameters of seedling growth promotion were evaluated 60 days after inoculation of seeds, with partition of the assessments into root and shoot weight. Each isolate showed beneficial, neutral or deleterious effects on plant growth, depending on the isolate and on the parts of plant assessed. Interestingly, although an apparent overall decrease in total biomass of seedlings (roots + shoots dry matters) was observed for the majority of isolates (89%), 94% of all isolates, in fact, revealed an increase in plant roots/shoots dry biomass ratio. Despite that part of the isolates (35%) appeared to significantly decrease plant height, and that 65% did not influence plant height (neutral effect), 18 had significantly increased root dry biomass; nevertheless, seven of these root growth-increasing isolates simultaneously decreased shoots-related growth parameters. The results of this study evidentiated the functional diversity of culturable cacao rhizobacteria and how the partitioning of roots and shoots in the assessment of plant growth parameters could reveal the biotechnological potential of these isolates for promoting growth of clones for rehabilitation of commercial cacao plantations.
Artigo
Assessing and understanding arsenic contamination in agricultural soils and lake sediments from papallacta rural Parish, Northeastern Ecuador, via ecotoxicology factors, for environmental embasement
(2023-02-21) Jimenez, Paul Andres Jimenez; Díaz, Ximena; Silva, Marx Leandro Naves; Vega, Anyela; Curi, Nilton
The concentration of arsenic (As), considered a toxic and carcinogenic metalloid, in agricultural soils has become a global challenge. Sources of arsenic in soils can be both anthropogenic and natural. Contaminated water is used for the irrigation of crops and vegetables, and therefore it is the main pathway for arsenic to enter the human food chain, creating a potential health risk. This study evaluated the concentrations of arsenic in agricultural soils in the rural parish of Papallacta, located 67 km east of the city of Quito, Northeastern Ecuador, and constitutes an analysis of the problem of arsenic in agricultural soils. Shallow groundwater and geothermal water discharges laced with arsenic are frequently used for irrigation and have raised the level of arsenic in agricultural soils. This work is focused on evaluating the environmental quality and contamination of agricultural soils through environmental quality indices such as geo-accumulation index, enrichment, and contamination factor. The average arsenic levels in the agricultural soils of the four studied areas fluctuate between 20.4 and 43.0 mg kg−1, while in the sediments of the Papallacta Lake, higher values were found in the range between 16.8 and 102.4 mg kg−1; all of which exceed the permissible limit by the Ecuadorian Environmental Legislation for agricultural use (12 mg kg−1). The results of the study in the five studied sites of the Papallacta civil parish indicate low to moderate levels of arsenic enrichment, soils enriched by bedrock, and moderate to considerable contamination.