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Lasting effect of Urochloa brizantha on a common bean-wheat-maize rotation in a medium-term no-till system
(2023-01-01) Crusciol, Carlos Alexandre Costa ; Santos Ferreira, João Henrique ; Momesso, Letusa ; Portugal, José Roberto ; de Campos, Murilo ; Volf, Marcelo Raphael ; Borghi, Emerson ; Soratto, Rogério Peres ; Calonego, Juliano Carlos ; Universidade Estadual Paulista (UNESP) ; São Paulo Western University (UNOEST) ; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)
Grass intercropping under no-till is an option to increase crop residues on the soil surface and crop diversity. Urochloa spp. is frequently selected for intercropping to improve land use and agricultural production because of its high residue production, slow residue decomposition, as well as its vigorous, abundant, and deep root system. However, the effects of intercropping Urochloa and maize, especially the effects of Urochloa residues, on subsequent crops in rotation have not been established. To address this knowledge gap, a field experiment was carried out over 5 years (from 2014 to 2018) comprising 2 years of maize monocropping or intercropping and 3 years of crop rotation (common bean-wheat-common bean-wheat-maize). We evaluated the medium-term effects of monocropped maize or maize intercropped with Urochloa brizantha on soil fertility and the development, yields, and grain nutrient accumulation of subsequent common bean, wheat, and maize crops. The cultivation of U. brizantha in the intercropping system improved soil fertility over at least 4 years, with increases in soil pH; soil organic matter (SOM); phosphorus (P); exchangeable potassium (K), calcium (Ca), and magnesium (Mg); sulfur (S–SO42−); cation exchange capacity (CEC); and base saturation (BS) at all soil depths. The benefits of U. brizantha extended to root dry matter and distribution; 70–77% of the total roots were concentrated within a soil depth of 0.0–0.2 m. The intercropping system improved the root dry matter mass, yield components, and grain yields of subsequent common bean, wheat, and maize crops in all cultivation years. These findings indicate that intercropping maize and U. brizantha provides medium-term benefits for subsequent common bean, wheat, and maize crops, and improves nutrient cycling to increase soil P; exchangeable K, Ca, and Mg; S–SO42−; and organic matter content.
Exploring chemical diversity in Glycine max cultivars: A multivariate approach in the search for bioactive compounds against Spodoptera cosmioides
(2022-09-02) Aguiar, Maria Clara Santana ; Mueller de Freitas, Marcelo ; de Freitas, Carlos Alessandro ; Boiça Júnior, Arlindo Leal ; Carneiro, Renato Lajarim ; da Silva, Maria Fátima das Graças Fernandes ; Fernandes, João Batista ; Forim, Moacir Rossi ; Universidade Federal de São Carlos (UFSCar) ; Universidade do Estado de São Paulo
Soybean crop is regulated by abiotic and biotic stresses with great potential in reducing grain yield and quality. The selection of resistant cultivars is a promising approach for mitigating these damages. We evaluated the chemical profile of Glycine max leaves from different cultivars in order to explore their defense mechanisms against Spodoptera cosmioides caterpillars. We optimized solid–liquid extraction techniques using ultrasound bath and static headspace extraction. Additionally, we developed an approach based on liquid and gas chromatography for analyzing the chemical profile of G. max cultivars. The principal component analysis allowed the classification of transgenic cultivars, which are classified as susceptible to S. cosmioides, from those obtained by genetic improvement and resistant to the insect. Differences were observed in the abundance of phenolic glycosides, lipids, aldehydes, and alcohols. More specifically, S. cosmioides resistant cultivars presented molecules related to the jasmonic and salicylic acid pathways. Such data can contribute to a molecular understanding of phenotypic diversity in soybean cultivars, from plant quality to resistance mechanisms and adaptation, to environmental stress and herbivory.
Comparison of hydrophilic and hydrophobic nano topographic surfaces of titanium alloys on pre-osteoblastic cell interaction
(2023-07-01) de Oliveira, Diego Pedreira ; Micocci, Kelli Cristina ; de Almeida, Gustavo Foresto Brito ; Otuka, Adriano José Galvani ; Mendonça, Cléber Renato ; Selistre-De-Araujo, Heloisa Sobreiro ; Bolfarini, Claudemiro ; Universidade Federal de São Carlos (UFSCar) ; Universidade Estadual Paulista (UNESP) ; Universidade Federal de Uberlândia (UFU) ; Universidade de São Paulo (USP)
This work aimed to assess the influence of different structured substrates with hydrophilic and hydrophobic properties on micro and nano topographies developed on titanium alloys over pre-osteoblastic cell behavior. Nano topography influences small dimension levels of cell morphology by inducing filopodia formation in cell membranes, irrespectively to the wettability behavior of the surface. Therefore, micro and nanostructured surfaces of titanium-based samples using different techniques of surface modification processing, such as chemical treatments, micro-arc anodic oxidation (MAO), and MAO combined to laser irradiation were developed. Isotropic and anisotropic texture morphologies, wettability, topological parameters and compositional alterations were measured after the surface treatments. Finally, cell viability, adhesion and morphological responses were assessed to investigate the influence of distinct topologies on osteoblastic cells aiming to encounter the conditions to better promote mineralization events. Our study demonstrated that the hydrophilic behavior improves cell adhesion, amplified when effective surface area increases. Surfaces presenting nano topography have a direct influence on cell morphology and play a key role for filopodia formation.
Bioactivity of plant extracts against Atta sexdens (Hymenoptera: Formicidae) workers by ingestion
(2023-01-01) Teixeira, Flávia Vidal ; de Melo Souza, Talytha R. ; Castellani, Maria A. ; da Silva Camargo, Roberto ; Forti, Luiz C. ; de Paula, Vanderlucia F. ; Silva, Aline ; de Matos, Carlos Alberto O. ; Nipato, Óscar B. ; Moreira, Aldenise Alves ; Sabattini, Julian Alberto ; UESB ; Universidade Estadual Paulista (UNESP) ; UESC ; National Council for Scientific and Technical Research
The leaf-cutting ant Atta sexdens stands out as a pest of several crops of economic importance. The main control method for this species is the application of ant baits. However, one of the most used active ingredients in the ant baits, sulfluramid, was classified as an organic pollutant, highlighting the urgent need to seek new active ingredients with greater ecological and environmental safety. The present goal is to evaluate the bioactivity of botanical extracts in workers of the leaf-cutting ant A. sexdens by ingestion, aiming to select extracts with essential characteristics for use in toxic baits for the subsequent isolation of substances and prospection of insecticides. Insect survival in the first evaluation (24 h) was high in all treatments with extracts. Survival time varied between treatments, with mortality reaching maximum values between 10 and 20 days for most of the treatments. At 21 days, live ants were observed only in treatments T3 (M. maracasana-stem) and T4 (C. mastigophorus-bark), with survival of 10% and 3.3%, respectively, not significantly differing between them. The extracts of Metrodorea maracasana, Conchocarpus mastigophorus, Erythoxylum macrocalyx, and Erythoxylum plowmanii showed insecticidal activity against A. sexdens workers. The insecticidal activity of the species Erythoxylum macrocalyx, E. plowmanii, Metrodorea maracasana, and Conchocarpus mastigophorus against A. sexdens workers is shown for the first time. The studied extracts have potential for the fractionation and selection of substances responsible for insecticidal activity, allowing for the prospection of toxic baits.
Deleterious Effects of Cymbopogon nardus (L.) Essential Oil on Life Cycle and Midgut of the Natural Predator Ceraeochrysa claveri (Navás, 1911) (Neuroptera: Chrysopidae)
(2023-04-01) Caballero-Gallardo, Karina ; Scudeler, Elton Luiz ; Carvalho dos Santos, Daniela ; Stashenko, Elena E. ; Olivero-Verbel, Jesus ; University of Cartagena ; Universidade Estadual Paulista (UNESP) ; Industrial University of Santander
Cymbopogon nardus (citronella) essential oil (EO) has been widely used in the cosmetic and food industry due to its repellent and fumigant properties. The aim of this study was to evaluate its effects on the life cycle and midgut morphology of the natural predator Ceraeochrysa claveri. Larvae were fed on sugarcane borer eggs (Diatraea saccharalis) pretreated with citronella EO solutions (1–100 µg/mL in methanol, 5 s) or solvent and air-dried at room temperature for 30 min. Larval and pupal stage duration, the percentage of emergence of the insect, and malformed insects were recorded. One day after adults emerged from their cocoons, adult insects were used to obtain their midgut and analyzed using light microscopy. The chemical composition of C. nardus EO revealed that citronellal (25.3%), citronellol (17.9%), geraniol (11.6%), elemol (6.5%), δ-cadinone (3.6%), and germacrene D (3.4%) were the predominant compounds. Exposure to the EO produced a significant change in development duration for third instar and prepupa of the insect. The observed alterations in the lifecycle included prepupae with no cocoon formation, dead pupa inside the cocoon, and malformed adults. Several injuries in the midgut epithelium of exposed adults were registered, such as detachment of columnar cells leaving only swollen regenerative cells fixed on the basement membrane, and the formation of epithelial folds. In summary, these data suggest that C. nardus oil has adverse effects on the life cycle and midgut morphology of a beneficial predator.
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(2023-06-01) Siviter, H. ; Fisher, A. ; Baer, B. ; Brown, M. J.F. ; Camargo, I. F. ; Cole, J. ; Le Conte, Y. ; Dorin, B. ; Evans, J. D. ; Farina, W. ; Fine, J. ; Fischer, L. R. ; Garratt, M. P.D. ; Giannini, T. C. ; Giray, T. ; Li-Byarlay, H. ; López-Uribe, M. M. ; Nieh, J. C. ; Przybyla, K. ; Raine, N. E. ; Ray, A. M. ; Singh, G. ; Spivak, M. ; Traynor, K. ; Kapheim, K. M. ; Harrison, J. F. ; University of Texas at Austin ; University of Bristol ; Arizona State University ; University of California Riverside ; Royal Holloway University of London ; Universidade Estadual Paulista (UNESP) ; University of Vermont ; INRAE ; York University ; USDA-ARS Bee Research Laboratory ; CONICET-UBA ; USDA-ARS ; University of East Anglia ; University of Reading ; (TCG) Instituto Tecnológico Vale ; University of Puerto Rico ; Central State University ; The Pennsylvania State University ; University of California San Diego ; University of Mons ; University of Guelph ; State College ; Western Sydney University ; Maharana Pratap Horticultural University ; University of Minnesota ; University of Hohenheim ; Utah State University
The article “Protecting pollinators and our food supply: understanding and managing threats to pollinator health”, written by H. Siviter, A. Fisher II, B. Baer, M. J. F. Brown, I. F. Camargo, J. Cole, Y. Le Conte, B. Dorin, J. D. Evans, W. Farina, J. Fine, L. R. Fischer, M. P. D. Garratt, T. C. Giannini, T. Giray, H. Li Byarlay, M. M. López Uribe, J. C. Nieh, K. Przybyla, N. E. Raine, A. M. Ray, G. Singh, M. Spivak, K. Traynor, K. M. Kapheim and J. F. Harrison”, was originally published electronically on the publisher’s internet portal on 2 January 2023 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 09 March 2023 to © The Author(s) 2022 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit. The original article has been corrected.
Azadirachtin-based insecticide impairs testis morphology and spermatogenesis of the southern armyworm Spodoptera eridania (Lepidoptera: Noctuidae)
(2023-05-01) Scudeler, Elton Luiz ; Daquila, Bruno Vinicius ; de Carvalho, Shelly Favorito ; Conte, Helio ; Padovani, Carlos Roberto ; dos Santos, Daniela Carvalho ; Universidade Estadual Paulista (UNESP) ; State University of Maringá
Background: In the search for alternative tools for integrated pest management, azadirachtin, a botanical insecticide, has been used with the most promising activity against Spodoptera spp., but the mechanism of cytotoxicity on reproductive organs remains unclear. Spodoptera eridania (Stoll, 1782) is a polyphagous pest with great economic importance that has become an important target to elucidate the action of azadirachtin on the reproductive organs of insect pests, helping to understand the deleterious effects caused by its exposure. This study evaluated the effects of chronic exposure to azadirachtin on the morphology and ultrastructure of S. eridania larval testes as well as larval development. Results: Azadirachtin exposure (6 or 18 mg a.i. L−1) caused a progressive increase in cumulative mortality and reduced gain in body mass after 5 days. Testicular structure indicated a reduction in their size with internal morphological changes such as spermatogonia, spermatogonial, spermatocytes and spermatid cysts in degeneration. The occurrence of cell death in germ and somatic cells was evidenced by the TUNEL technique. Electron microscopy revealed changes in cystic cells, such as cytoplasmic membrane rupture and cytoplasmic vacuolization. Chromatin compaction, changes in the rough endoplasmic reticulum and Golgi complex cisternae were observed in germ cells. Apoptotic bodies occurred between germ cell cysts. Conclusion: Azadirachtin damaged the testes of S. eridania larvae, and these changes compromised spermatogenesis and consequently the development of the reproductive potential of this specimen, making azadirachtin a promising botanical insecticide for application in integrated pest management programs. © 2022 Society of Chemical Industry.
Protecting pollinators and our food supply: understanding and managing threats to pollinator health
(2023-02-01) Siviter, H. ; Fisher, A. ; Baer, B. ; Brown, M. J.F. ; Camargo, I. F. ; Cole, J. ; Le Conte, Y. ; Dorin, B. ; Evans, J. D. ; Farina, W. ; Fine, J. ; Fischer, L. R. ; Garratt, M. P.D. ; Giannini, T. C. ; Giray, T. ; Li-Byarlay, H. ; López-Uribe, M. M. ; Nieh, J. C. ; Przybyla, K. ; Raine, N. E. ; Ray, A. M. ; Singh, G. ; Spivak, M. ; Traynor, K. ; Kapheim, K. M. ; Harrison, J. F. ; University of Texas at Austin ; University of Bristol ; Arizona State University ; University of California Riverside ; Royal Holloway University of London ; Universidade Estadual Paulista (UNESP) ; University of Vermont ; INRAE ; York University ; USDA-ARS Bee Research Laboratory ; CONICET-UBA ; USDA-ARS ; University of East Anglia ; University of Reading ; Instituto Tecnológico Vale ; University of Puerto Rico ; Central State University ; The Pennsylvania State University ; University of California San Diego ; University of Mons ; University of Guelph ; Pennsylvania State University ; Western Sydney University ; Maharana Pratap Horticultural University ; University of Minnesota ; University of Hohenheim ; Utah State University
Global pollinator declines threaten food production and natural ecosystems. The drivers of declines are complicated and driven by numerous factors such as pesticide use, loss of habitat, rising pathogens due to commercial bee keeping and climate change. Halting and reversing pollinator declines will require a multidisciplinary approach and international cooperation. Here, we summarize 20 presentations given in the symposium ‘Protecting pollinators and our food supply: Understanding and managing threats to pollinator health’ at the 19th Congress of the International Union for the Study of Social Insects in San Diego, 2022. We then synthesize the key findings and discuss future research areas such as better understanding the impact of anthropogenic stressors on wild bees.
Impact of native vegetation cover near crops on the occurrence and molecular diversity of fire ants
(2023-05-01) Nagatani, Victor H. ; Ramalho, Manuela O. ; Alves, Juliana M. C. ; Souza, Rodrigo F. ; Kayano, Débora Y. ; Silva, Nathalia S. ; Silva, Otávio G. M. ; Harakava, Ricardo ; Bueno, Odair C. ; Hilsdorf, Alexandre W. S. ; Morini, Maria S. C. ; UMC-University of Mogi das Cruzes ; West Chester University ; Coordination of Earth Sciences and Ecology ; Laboratório de Bioquímica Fitopatologia ; Universidade Estadual Paulista (UNESP)
Solenopsis invicta and Solenopsis saevissima are the most common fire ants in Brazil. Environmental disturbances favour the colony dispersal of both species, particularly those with an anthropogenic origin. However, the frequencies of the species can vary according to the amount of anthropogenic disturbances. Crops near native vegetation fragments is a common landscape in the Brazilian Atlantic Forest. Here, we analyse if there is influence of native vegetation cover on the occurrence of these fire ants and their molecular diversity in crops. Our hypothesis is that these species are antagonistic in terms of occurrence and molecular diversity when compared in the same habitat. We selected crops near fragments with around 50% of native vegetation cover, a percentage informative enough to detect biological responses from insects belonging to a same order. Nests were collected and the species were identified using external morphology, and mtDNA COI sequences. We reject our hypothesis, which suggest that the species colonize the vegetation patches around crops in a similar way. Solenopsis invicta is not limited by vegetation cover, and has a high haplotype diversity when compared to S. saevissima, particularly when the vegetation cover is greater than 50%. Additionally, the vegetation cover seems to not have influence in the total number of haplotypes, but the species have haplotypes that are exclusive to each landscape. Our findings suggest that S. invicta is expanding to native vegetation areas that it has not occupied before, as S. saevissima was dominant there.
Small Extracellular Vesicles from Hypoxic Triple-Negative Breast Cancer Cells Induce Oxygen-Dependent Cell Invasion
(2022-10-01) Pachane, Bianca Cruz ; Nunes, Ana Carolina Caetano ; Cataldi, Thais Regiani ; Micocci, Kelli Cristina ; Moreira, Bianca Caruso ; Labate, Carlos Alberto ; Selistre-de-Araujo, Heloisa Sobreiro ; Altei, Wanessa Fernanda ; Universidade Federal de São Carlos (UFSCar) ; Universidade de São Paulo (USP) ; Universidade Estadual Paulista (UNESP) ; Barretos Cancer Hospital
Hypoxia, a condition of low oxygenation frequently found in triple-negative breast tumors (TNBC), promotes extracellular vesicle (EV) secretion and favors cell invasion, a complex process in which cell morphology is altered, dynamic focal adhesion spots are created, and ECM is remodeled. Here, we investigated the invasive properties triggered by TNBC-derived hypoxic small EV (SEVh) in vitro in cells cultured under hypoxic (1% O2) and normoxic (20% O2) conditions, using phenotypical and proteomic approaches. SEVh characterization demonstrated increased protein abundance and diversity over normoxic SEV (SEVn), with enrichment in pro-invasive pathways. In normoxic cells, SEVh promotes invasive behavior through pro-migratory morphology, invadopodia development, ECM degradation, and matrix metalloprotease (MMP) secretion. The proteome profiling of 20% O2-cultured cells exposed to SEVh determined enrichment in metabolic processes and cell cycles, modulating cell health to escape apoptotic pathways. In hypoxia, SEVh was responsible for proteolytic and catabolic pathway inducement, interfering with integrin availability and gelatinase expression. Overall, our results demonstrate the importance of hypoxic signaling via SEV in tumors for the early establishment of metastasis.
Identification, cloning, and characterization of a novel chitinase from leaf-cutting ant Atta sexdens: An enzyme with antifungal and insecticidal activity
(2023-01-01) Micocci, Kelli C. ; Moreira, Ariele C. ; Sanchez, Amanda D. ; Pettinatti, Jessica L. ; Rocha, Marina C. ; Dionizio, Bruna S. ; Correa, Katia C.S. ; Malavazi, Iran ; Wouters, Felipe C. ; Bueno, Odair C. ; Souza, Dulce Helena F. ; Universidade Estadual Paulista (UNESP) ; Universidade Federal de São Carlos (UFSCar)
Chitinases are enzymes that degrade chitin, a polysaccharide found in the exoskeleton of insects, fungi, yeast, and internal structures of other vertebrates. Although chitinases isolated from bacteria, fungi and plants have been reported to have antifungal or insecticide activities, chitinases from insects with these activities have been seldomly reported. In this study, a leaf-cutting ant Atta sexdens DNA fragment containing 1623 base pairs was amplified and cloned into a vector to express the protein (AsChtII-C4B1) in Pichia pastoris. AsChtII-C4B1, which contains one catalytic domain and one carbohydrate-binding module (CBM), was secreted to the extracellular medium and purified by ammonium sulfate precipitation followed by nickel column chromatography. AsChtII-C4B1 showed maximum activity at pH 5.0 and 55 °C when tested against colloidal chitin substrate and maintained >60% of its maximal activity in different temperatures during 48 h. AsChtII-C4B1 decreased the survival of Spodoptera frugiperda larvae fed with an artificial diet that contained AsChtII-C4B1. Our results have indicated that AsChtII-C4B1 has a higher effect on larva-pupa than larva-larva molts. AsChtII-C4B1 activity targets more specifically the growth of filamentous fungus than yeast. This work describes, for the first time, the obtaining a recombinant chitinase from ants and the characterization of its insecticidal and antifungal activities.
Harmful Effects of Pyraclostrobin on the Fat Body and Pericardial Cells of Foragers of Africanized Honey Bee
(2022-09-01) Inoue, Lais V. B. ; Domingues, Caio E. C. ; Gregorc, Aleš ; Silva-Zacarin, Elaine C. M. ; Malaspina, Osmar ; Universidade Estadual Paulista (UNESP) ; University of Maribor ; Universidade Federal de São Carlos (UFSCar)
Managed honey bees are daily exposed in agricultural settings or wild environments to multiple stressors. Currently, fungicide residues are increasingly present in bees’ pollen and nectar and can harm colonies’ production and survival. Therefore, our study aimed to evaluate the effects of the fungicide pyraclostrobin on the fat body and pericardial cells of Africanized honey bees. The foragers were divided into three experimental treatment groups and two controls: pyraclostrobin 0.125 ng/µL (FG1), 0.025 ng/µL (FG2), 0.005 ng/µL (FG3), untreated control (CTL), and acetone control (CAC). After five days of oral exposure (ad libitum), the bees were dissected and prepared for histopathological and morphometric analysis. The FG1-treated bees showed extensive cytoarchitecture changes in the fat body and pericardial cells, inducing cell death. Bees from the FG2 group showed disarranged oenocytes, peripheral vacuolization, and pyknotic nuclei of pericardial cells, but the cytoarchitecture was not compromised as observed in FG1. Additionally, immune system cells were observed through the fat body in the FG1 group. Bees exposed to FG3 demonstrated only oenocytes vacuolization. A significant decrease in the oenocyte’s surface area for bees exposed to all pyraclostrobin concentrations was observed compared to the CTL and CAC groups. The bees from the FG1 and FG2 treatment groups presented a reduced surface area of pericardial cells compared to the controls and the FG3 group. This study highlighted the harmful effects of fungicide pyraclostrobin concentrations at the individual bee cellular level, potentially harming the colony level on continuous exposure.
Identification and characterization of a recombinant cysteine peptidase (AsCathL) from leaf-cutting ant Atta sexdens Linnaeus, 1758 (Hymenoptera, Formicidae)
(2023-01-01) Santos Correa, Katia Celina ; Moreira, Ariele Cristina ; Abd El-Raheem Ibrahim, Amr Galal ; Ramos de Jesus, Hugo César ; Micocci, Kelli Cristina ; Crizóstomo Kock, Flávio Vinícius ; Bueno, Odair C. ; Venâncio, Tiago ; Henrique-Silva, Flávio ; Souza, Dulce Helena F. ; Universidade Federal de São Carlos (UFSCar) ; Universidade de São Paulo (USP) ; Universidade Estadual Paulista (UNESP)
Cysteine peptidases are involved in physiological processes of insect development and have been considered as potential targets for the development of insect control strategies. In this study, we obtained a recombinant cysteine cathepsin L (AsCathL) from leaf-cutting ant (Atta sexdens), a species from the order Hymenoptera who causes enormous damage to crops, natural forests and reforested areas. RT-qPCR showed AsCathL expression throughout insect development and in all body parts of the adult insect analysed, suggesting its role as a lysosomal cathepsin. AsCathL encodes a protein of 320 amino acid residues consisting of a pro-peptide and the mature with amino acids sequence over 67% similarity with lysosomal cathepsin L of species from Lepidoptera and Diptera. Phylogenetic tree revealed that AsCathL is very similar to predicted cathepsins found in other ants. Recombinant AsCathL was expressed in insoluble form by Escherichia coli Arctic Express (DE3) RIL, purified under denaturing conditions and refolded. The enzyme showed hydrolytic activity in vitro towards synthetic substrate Z-Phe-Arg-AMC at acidic pH. Synthetic inhibitor E−64 acted against peptidase activity and a study regarding the interaction between E−64 and AsCathL using nuclear magnetic resonance (NMR) revealed that 83.18% from all E−64 molecules are irreversibly bound to AsCathL. In addition, the proteolytic activity of AsCathL was strongly inhibited by recombinant sugarcane cystatins with Ki ranging from 0.6 nM to 2.95 nM. To the best of our knowledge this is the first report characterizing a cysteine peptidase from leaf-cutting ants, which may contribute to future studies of ants’ cathepsins.
Novel viruses of the family Partitiviridae discovered in Saccharomyces cerevisiae
(Public Library Science, 2023-06-01) Taggart, Nathan T. E. ; Crabtree, Angela M. A. ; Creagh, Jack W. M. ; Bizarria, Rodolfo M. ; Li, Shunji ; la Higuera, Ignacio A. de ; Barnes, Jonathan E. ; Shipley, Mason A. ; Boyer, Josephine M. ; Stedman, Kenneth M. ; Ytreberg, F. Marty ; Rowley, Paul A. ; Univ Idaho ; Universidade Estadual Paulista (UNESP) ; Portland State Univ
It has been 49 years since the last discovery of a new virus family in the model yeast Saccharomyces cerevisiae. A large-scale screen to determine the diversity of double-stranded RNA (dsRNA) viruses in S. cerevisiae has identified multiple novel viruses from the family Partitiviridae that have been previously shown to infect plants, fungi, protozoans, and insects. Most S. cerevisiae partitiviruses (ScPVs) are associated with strains of yeasts isolated from coffee and cacao beans. The presence of partitiviruses was confirmed by sequencing the viral dsRNAs and purifying and visualizing isometric, non-enveloped viral particles. ScPVs have a typical bipartite genome encoding an RNA-dependent RNA polymerase (RdRP) and a coat protein (CP). Phylogenetic analysis of ScPVs identified three species of ScPV, which are most closely related to viruses of the genus Cryspovirus from the mammalian pathogenic protozoan Cryptosporidium parvum. Molecular modeling of the ScPV RdRP revealed a conserved tertiary structure and catalytic site organization when compared to the RdRPs of the Picornaviridae. The ScPV CP is the smallest so far identified in the Partitiviridae and has structural homology with the CP of other partitiviruses but likely lacks a protrusion domain that is a conspicuous feature of other partitivirus particles. ScPVs were stably maintained during laboratory growth and were successfully transferred to haploid progeny after sporulation, which provides future opportunities to study partitivirus-host interactions using the powerful genetic tools available for the model organism S. cerevisiae. Author summaryThis article describes the discovery and characterization of multiple strains and species of viruses from the family Partitiviridae in the brewer's and baker's yeast S. cerevisiae. These novel viruses have bipartite genomes packaged in spherical viral particles with structural homology to members of the family Partitiviridae. Strikingly, yeast partitiviruses are most closely related to viruses from human pathogenic protozoa and not partitiviruses of other fungi. As partitiviruses can positively and negatively contribute to a host's physiology (including important human and plant pathogens), the presence of partitiviruses in S. cerevisiae offers a unique opportunity to study the biology of these viruses in a well-developed model system.
Uncovering the Yeast Communities in Fungus-Growing Ant Colonies
(2022-01-01) Bizarria, Rodolfo ; de Castro Pietrobon, Tatiane ; Rodrigues, Andre ; Universidade Estadual Paulista (UNESP)
Yeast-insect interactions are compelling models to study the evolution, ecology, and diversification of yeasts. Fungus-growing (attine) ants are prominent insects in the Neotropics that evolved an ancient fungiculture of basidiomycete fungi over 55–65 million years, supplying an environment for a hidden yeast diversity. Here we assessed the yeast diversity in the attine ant environment by thoroughly sampling fungus gardens across four out of five ant fungiculture systems: Acromyrmex coronatus and Mycetomoellerius tucumanus standing for leaf-cutting and higher-attine fungicultures, respectively; Apterostigma sp., Mycetophylax sp., and Mycocepurus goeldii as ants from the lower-attine fungiculture. Among the fungus gardens of all fungus-growing ants examined, we found taxonomically unique and diverse microbial yeast communities across the different fungicultures. Ascomycete yeasts were the core taxa in fungus garden samples, with Saccharomycetales as the most frequent order. The genera Aureobasidium, Candida, Papiliotrema, Starmerella, and Sugiyamaella had the highest incidence in fungus gardens. Despite the expected similarity within the same fungiculture system, colonies of the same ant species differed in community structure. Among Saccharomycotina yeasts, few were distinguishable as killer yeasts, with a classical inhibition pattern for the killer phenotype, differing from earlier observations in this environment, which should be further investigated. Yeast mycobiome in fungus gardens is distinct between colonies of the same fungiculture and each ant colony harbors a distinguished and unique yeast community. Fungus gardens of attine ants are emergent environments to study the diversity and ecology of yeasts associated with insects.
Predation of Diatraea saccharalis eggs and neonates by the earwig Euborellia annulipes
(2022-09-01) de Souza, Joice Mendonça ; Seleghim, Aimée Regali ; da Silva Nunes, Gilmar ; Truzi, Caio Cesar ; Vieira, Natalia Fernanda ; De Bortoli, Sergio Antonio ; Universidade Estadual Paulista (UNESP)
Diatraea saccharalis (Lepidoptera: Crambidae) is a key sugarcane pest in South America. The prohibition of crop burning and soil conservation programs have allowed several natural enemies of sugarcane borer to increase population their densities. The earwig Euborellia annulipes (Lucas) (Dermaptera: Anisolabididae) is a generalist predator often found in sugarcane fields that will prey on eggs and larvae of D. saccharalis. This study used choice and no-choice tests to assess consumption of D. saccharalis eggs and neonate larvae by different earwig life stages in a 12 h period. The mean predation rates of E. annulipes nymphs and adults were estimated and their relative preference for eggs versus neonate larvae was analyzed by Manly's preference index. The functional responses of fourth and fifth instar nymphs and male and female adults were evaluated over 24 h. The mean predation rate was highest on neonate larvae, and this life stage preferred the most preferred (ß = 0.98). Fourth and fifth instars and adults consumed more prey (both eggs and larvae) than earlier life stages, and their functional responses varied with life stage of both predator and prey. Females exhibited a type III response when preying on neonate larvae, which had the shortest handling time. All life stages of E. annulipes consumed both eggs and larvae, preferring the D. saccharalis neonate larvae.
Monitoring the effects of field exposure of acetamiprid to honey bee colonies in Eucalyptus monoculture plantations
(2022-10-20) da Costa Domingues, Caio Eduardo ; Sarmento, Artur Miguel Paiva ; Capela, Nuno Xavier Jesus ; Costa, José Miguel ; Mina, Rúben Miguel Rodrigues ; da Silva, António Alves ; Reis, Ana Raquel ; Valente, Carlos ; Malaspina, Osmar ; Azevedo-Pereira, Henrique M.V.S. ; Sousa, José Paulo ; Faculty of Agriculture and Life Sciences ; Universidade Estadual Paulista (UNESP) ; University of Coimbra ; Altri Florestal ; RAIZ - Instituto de Investigação da Floresta e Papel ; ForestWISE - Collaborative Laboratory for Integrated Forest & Fire Management
Eucalyptus plantations occupy 26 % of Portuguese forested areas. Its flowers constitute important sources for bees and beekeepers take advantage of this and keep their honey bee colonies within or near the plantations for honey production. Nonetheless, these plantations are susceptible to pests, such as the eucalyptus weevil Gonipterus platensis. To control this weevil, some plantations must be treated with pesticides, which might harm non-target organisms. This study aimed to perform a multifactorial assessment of the health status and development of Apis mellifera iberiensis colonies in two similar landscape windows dominated by Eucalyptus globulus plantations - one used as control and the other with insecticide treatment. In each of the two selected areas, an apiary with five hives was installed and monitored before and after a single application of the insecticide acetamiprid (40 g a.i./ha). Colony health and development, resources use, and pesticide residues accumulation were measured. The results showed that the application of acetamiprid in this area did not alter the health status and development of the colonies. This can be explained by the low levels of residues of acetamiprid detected only in pollen and bee bread samples, ~52 fold lower than the sublethal effect threshold. This could be attributed to the low offer of resources during and after the application event and within the application area, with the consequent foraging outside the sprayed area during that period. Since exposure to pesticides in such complex landscapes seems to be dependent on the spatial and temporal distribution of resources, we highlight some key monitoring parameters and tools that are able to provide reliable information on colony development and use of resources. These tools can be easily applied and can provide a better decision-taking of pesticide application in intensive production systems to decrease the risk of exposure for honey bees.
Lessons From Insect Fungiculture: From Microbial Ecology to Plastics Degradation
(2022-05-24) Barcoto, Mariana O. ; Rodrigues, Andre ; Universidade Estadual Paulista (UNESP)
Anthropogenic activities have extensively transformed the biosphere by extracting and disposing of resources, crossing boundaries of planetary threat while causing a global crisis of waste overload. Despite fundamental differences regarding structure and recalcitrance, lignocellulose and plastic polymers share physical-chemical properties to some extent, that include carbon skeletons with similar chemical bonds, hydrophobic properties, amorphous and crystalline regions. Microbial strategies for metabolizing recalcitrant polymers have been selected and optimized through evolution, thus understanding natural processes for lignocellulose modification could aid the challenge of dealing with the recalcitrant human-made polymers spread worldwide. We propose to look for inspiration in the charismatic fungal-growing insects to understand multipartite degradation of plant polymers. Independently evolved in diverse insect lineages, fungiculture embraces passive or active fungal cultivation for food, protection, and structural purposes. We consider there is much to learn from these symbioses, in special from the community-level degradation of recalcitrant biomass and defensive metabolites. Microbial plant-degrading systems at the core of insect fungicultures could be promising candidates for degrading synthetic plastics. Here, we first compare the degradation of lignocellulose and plastic polymers, with emphasis in the overlapping microbial players and enzymatic activities between these processes. Second, we review the literature on diverse insect fungiculture systems, focusing on features that, while supporting insects’ ecology and evolution, could also be applied in biotechnological processes. Third, taking lessons from these microbial communities, we suggest multidisciplinary strategies to identify microbial degraders, degrading enzymes and pathways, as well as microbial interactions and interdependencies. Spanning from multiomics to spectroscopy, microscopy, stable isotopes probing, enrichment microcosmos, and synthetic communities, these strategies would allow for a systemic understanding of the fungiculture ecology, driving to application possibilities. Detailing how the metabolic landscape is entangled to achieve ecological success could inspire sustainable efforts for mitigating the current environmental crisis.
Crescimento radicular e aéreo de cultivares de arroz de terras altas em função da calagem
(2012-09-11) Crusciol, Carlos Alexandre Costa ; Mancuso, Mauricio Antonio Cuzato ; Garcia, Rodrigo Arroyo ; Castro, Gustavo Spadotti Amaral ; Universidade Estadual Paulista (UNESP) ; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)
This work aimed to evaluate root growth, shoot development and nutrient absorption efficiency by rice cultivars Caiapó and Maravilha as affected by lime application. The experiment was carried out in a greenhouse, with treatments set up by Caiapó and Maravilha cultivars in combination with the base saturation (V%) of 10%, 40% and 70%. The experiment was in a randomized complete block design, with four replications. The number of tillers, root length, root dry matter, leaves and stems, leaf content and macronutrients absorption efficiency were evaluated. Comparing cultivars, Maravilha cultivar presented higher root dry weight, root length, number of stems, dry matter of stems and shoot than Caiapó cultivar, as well as accumulated more nutrients in the shoots. On the other hand, nutrient contents were higher in the cultivar Caiapó compared to Maravilha. Maravilha cultivar shows greater root and shoot growth while Caiapó shows higher nutrient absorption efficiency from the soil. The base saturation of 40% is the most effective for both cultivars.
The Genome of “Candidatus Liberibacter asiaticus” Is Highly Transcribed When Infecting the Gut of Diaphorina citri
(2021-07-12) Darolt, Josiane Cecília ; Bento, Flavia de Moura Manoel ; Merlin, Bruna Laís ; Peña, Leandro ; Cônsoli, Fernando Luis ; Wulff, Nelson Arno ; Universidade Estadual Paulista (UNESP) ; Fundo de Defesa da Citricultura – Fundecitrus ; Universidade de São Paulo (USP) ; Universidade Politécnica de Valencia
The Asian citrus psyllid, Diaphorina citri, is the vector of the bacterium “Candidatus Liberibacter asiaticus” (Las), associated with the devastating, worldwide citrus disease huanglongbing. In order to explore the molecular interactions of this bacterium with D. citri during the vector acquisition process, cDNA libraries were sequenced on an Illumina platform, obtained from the gut of adult psyllids confined in healthy (H) and in Las-infected young shoots (Las) for different periods of times (I = 1/2 days, II = 3/4 days, and III = 5/6 days). In each sampling time, three biological replicates were collected, containing 100 guts each, totaling 18 libraries depleted in ribosomal RNA. Reads were quality-filtered and mapped against the Chinese JXGC Las strain and the Floridian strain UF506 for the analysis of the activity of Las genome and SC1, SC2, and type 3 (P-JXGC-3) prophages of the studied Las strain. Gene activity was considered only if reads of at least two replicates for each acquisition access period mapped against the selected genomes, which resulted in coverages of 44.4, 79.9, and 94.5% of the JXGC predicted coding sequences in Las I, Las II, and Las III, respectively. These genes indicate an active metabolism and increased expression according to the feeding time in the following functional categories: energy production, amino acid metabolism, signal translation, cell wall, and replication and repair of genetic material. Pilins were among the most highly expressed genes regardless of the acquisition time, while only a few genes from cluster I of flagella were not expressed. Furthermore, the prophage region had a greater coverage of reads for SC1 and P-JXGC-3 prophages and low coverage in SC2 and no indication of activity for the lysis cycle. This research presents the first descriptive analysis of Las transcriptome in the initial steps of the D. citri gut colonization, where 95% of Las genes were active.

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