Biological Institute

Plant viruses both trigger and inhibit host plant defense responses, including defenses that target their insect vectors, such as aphids. Turnip mosaic viru (TuMV) infection and its protein, NIa-Pro (nuclear inclusion protease a), suppress aphid-induced plant defenses, however the mechanisms of this suppression are still largely unknown. In this study, we determined that NIa-Pro’s protease activity is required to increase aphid performance on host plants and that 40 transcripts with predicted NIa-Pro cleavage sequences are regulated in Arabidopsis plants challenged with aphids and/or virus compared to healthy controls. One of the candidates, MEDIATOR 16 (MED16), regulates the transcription of ethylene (ET)/jasmonic acid (JA)-dependent defense responses against necrotrophic pathogens. We show that a nuclear localization signal is removed from MED16 by specific proteolytic cleavage in virus-infected plants and in plants overexpressing NIa-Pro in the presence of aphids. Although some cleavage was occasionally detected in the absence of virus infection, it occurred at a much higher rate in plants that were virus-infected or overexpressing NIa-Pro, especially when aphids were also present. This suggests MED16 functions in the nucleus may be impacted in virus infected plants. Consistent with this, induction of the MED16-dependent transcript of PLANT DEFENSIN 1.2 (PDF1.2), was reduced in virus-infected plants and in plants expressing NIa-Pro compared to controls, but not in plants expressing NIa-Pro C151A that lacks its protease activity. Finally, we show the performance of both the virus and the aphid vector was enhanced on med16 mutant Arabidopsis compared to controls. Overall, this study demonstrates MED16 regulates defense responses against both the virus and the aphid and provides insights into the mechanism by which TuMV suppresses anti-virus and anti-herbivore defenses. Supplementary Information The online version contains supplementary material available at 10.1186/s12870-025-06411-2.

Trissolcus adrianae Costa & Johnson, sp. nov. is described. It is an egg parasitoid of the neotropical bark bug Phloea subquadrata Spinola (Hemiptera, Phloeidae) on Plinia cauliflora (Mart.) Kausel (Myrtales, Myrtaceae). Trissolcus adrianae belongs to the flavipes species group and can easily be distinguished from other flavipes group members by its noticeably depressed habitus; head oblong in anterior view; bidentate mandibles; frontal depression delimited dorsally by carina; orbital furrow sculptured, constricted through most of its length by lateral expansion of frons; notauli absent; and the length of T3–T6 subequal to the length of T2. This is the first species of Scelionidae associated with the family Phloeidae (Hemiptera: Pentatomoidea) and the first report of parasitism of Phloeidae eggs as well.

Siphoninus phillyreae (Haliday) (Hemiptera: Aleyrodidae) is a polyphagous species with a wide geographical distribution and high invasive potential. In South America, it has been documented in Venezuela, Chile, Peru and Argentina. Leaves of pomegranate [Punica granatum L. (Lythraceae)] containing whitefly eggs, nymphs, puparia, and adults were collected in the municipalities of Campinas, Piracicaba (São Paulo), Planaltina (Goiás), São João dos Patos (Maranhão), Floriano (Piauí), and Janaúba (Minas Gerais). Based on morphological characters, the species was identified as S. phillyreae in the collections. Additionally, parasitism by Encarsia brasiliensis (Hempel) (Hymenoptera: Aphelinidae) was observed in Piracicaba. The adults collected in Piracicaba underwent molecular characterization, validating the morphological identification. In Brazil, the pomegranate tree is often grown as an ornamental plant in gardens due to its beautiful leaves, flowers, fruits, and medicinal properties. Thus, due to the increase in pomegranate cultivation, an appropriate management plan for this pest is necessary. Therefore, this is the first record of the S. phillyreae in Brazil, expanding its distribution in South America.

An isolate of the tobamovirus tobacco mild green mosaic virus (TMGMV), Tobamovirus mititessellati, was found naturally infecting petunia (Petunia × hybrida) cv. Pinstripe, causing reduced leaf size, mottling, and color breaking of flowers, in an experimental field at Piracicaba, São Paulo state, Brazil. TMGMV was identified by virion morphology, cytopathology, transmission experiments, and molecular assays. The entire nucleotide sequence of this petunia isolate of TMGMV (TMGMV-Pet) was obtained and demonstrated, in essence, to be similar to previously analyzed isolates. One hundred and twenty plant species were assayed by mechanical transmission, and 35 of them from nine families, both previously reported and unreported species, were shown to be experimentally susceptible to TMGMV-Pet. On the other hand, certain species, among 85 unsusceptible hosts for TMGMV-Pet, known to be susceptible to TMGMV, failed to be infected. Cytopathological studies on naturally and experimentally infected host plants revealed that virions of TMGMV-Pet produced para-crystalline aggregates, but not angular arrays, which are considered characteristic of TMGMV. As previously described, thin sections revealed the presence of pseudo-virions in the stroma of chloroplasts in TMGMV-Pet-infected tobacco (Nicotiana tabacum), and, additionally, in other hosts such as N. clevelandii, N. megalosyphon, and petunia indicating that this process is not restricted to tobacco. Keywords cytopathology ; experimental host range; genome stability; pseudo-virions in chloroplasts; tobamovirus

Papaya ringspot virus strain P (PRSV-P) is the causative agent of one of the most devastating viral diseases affecting papaya cultivation regions. Although high resistance in papaya has not been reported, global papaya germplasm exhibits considerable diversity, leading to the identification of tolerant genotypes. In the present study, we assessed the resistance levels of 43 papaya accessions to PRSV-P. Disease evaluations were conducted by mechanically inoculating two-month-old papaya seedlings with a PRSV-P isolate and subsequently scoring them on a disease grading scale ranging from 0 to 5. The incubation period (IP) demonstrated a strong negative correlation of -0.82 with the disease index (DI) and -0.77 with the area under the disease progress curve (AUDPC). The DI and AUDPC displayed a perfect correlation of 0.99. Based on the DI values, the evaluated accessions were categorized as moderately susceptible or susceptible. The ‘Cariflora’ accession, previously reported as PRSV-P tolerant, exhibited the lowest DI at 37.33%, whereas São Mateus displayed the highest disease index at 62.67%. Although no accession was classified as moderately resistant or resistant, we will continue to assess papaya accessions for their resistance to PRSV-P infection, with the addition of more genotypes to the UENF/CALIMAN germplasm bank, especially adding dioecious genotypes.

Aims This prospective cross-sectional study aimed to determine the occurrence of resistance genes and genetic diversity in Staphylococcus spp., Enterococcus spp., and Escherichia coli isolated from dogs' superficial surgical site (SS), surgeons' hands, and the operating room (OR) during the intraoperative period. Methods Thirty dogs undergoing clean/clean-contaminated (G1, n = 20) and contaminated surgeries (G2, n = 10), along with eight surgeons, were included in the study. Specimens were collected using sterile swabs, transported in 0.1% peptone salt solution, and spread onto blood agar. Environmental samples were collected through passive exposure using BHI agar plates. Seventy-five isolates were selected and classified using MALDI-TOF MS. Resistance genes were screened via PCR: tet(M), ermA, aacA-aphD, blaZ, mecA, blaTEM-1, blaSHV, blaSHV-1, blaCTX-M-1, 3 e 15, blaCTX-M-2, blaCMY-2, mcr1, mcr2, mcr3, mcr4, and ndm. Genetic diversity was assessed through PFGE analysis using SmaI and XbaI restriction enzymes, with clustering performed by the UPGMA method. The chi-square test compared the frequency of resistance gene detected. Results Staphylococcus pseudintermedius (83.33%), Enterococcus spp. (52.63%), and E. coli (62.50%) were more frequently isolated from dogs' skin, while coagulase-negative staphylococci (CoNS; 62.50%) were more frequent in the OR. Resistance genes detected in Staphylococcus spp. included blaZ (79.17%), mecA (43.75%), tet(M) (41.67%), and aacA-aphD (25%). Among Enterococcus spp., tet(M) (78.95%) and blaZ (10.53%) were identified. S. pseudintermedius harbored tet(M) and aacA-aphD genes more frequently than CoNS. No E. coli isolates tested positive for the investigated genes. Twenty-four PFGE banding patterns were observed in CoNS (24/24), 15 in S. pseudintermedius (15/24), 4 in E. coli (4/8), and 7 in Enterococcus spp. (7/19). Genetically related S. pseudintermedius and E. coli were obtained from SS and OR in G2. Seven indistinguishable Enterococcus spp. were identified across different procedures and patients. Conclusion Our study revealed high rates of methicillin-resistant Staphylococcus spp. and tetracycline-resistant Enterococcus spp. colonizing the environment in a veterinary teaching hospital in Brazil. PFGE analysis indicated a high diversity of CoNS and Enterococcus spp. Genetically related strains in S. pseudintermedius, Enterococcus spp., and E. coli emphasize the importance of effective infection control policies to minimize the spread of resistant bacteria.

Aim We investigated the effects of plant growth-promoting bacteria (PGPB) on the growth and nutrition of coffee seedlings and the biological control of coffee leaf rust (Hemileia vastatrix), brown eye spot (Cercospora coffeicola), and leaf blight (Boeremia coffeae). Methods and results In the first part of the study, nineteen PGPB strains obtained in the phyllosphere, endosphere and rhizosphere of coffee and other hosts, produced varied metabolites related to plant growth and biological control. Two coffee cultivars were treated with the bacterial strains, but cultivar Catuaí Amarelo IAC 62 was less responsive to the treatments. Five rhizospheric strains, from different genera, Bacillus cereus (Rb1), Pseudomonas koreensis (Rb2b), Enterobacter mori (Mn2), B. safensis (Ob3a), Enterobacter cloacae (RBca5) and two endophytic strains, Enterobacter hormaechei (EOb1) and Paraburkholderia caribensis (Beca88) enhanced seed germination, plant biomass, and nutrient accumulation in cultivar ‘Catuaí Vermelho’ IAC144 seedlings. In the second part of the study, three strains, the phyllospheric Pseudomonas gozinkensis (Mn1F), the endophytic Paraburkholderia caribensis (BEca88) and the rhizospheric Enterobacter cloacae (RBca5) reduced the severity of coffee leaf rust, brown eye spot and leaf blight. Conclusions PGPB from different genera, obtained in varied hosts and habitats showed positive effect, improving plant fitness and controlling important coffee diseases, standing out the strains Pseudomonas gozinkensis (Mn1F), Paraburkholderia caribensis (IAC-BEca-088) and Enterobacter cloacae (IAC-RBca5).

https://rdcu.be/eahLW

Soybean crops are affected by various diseases that cause significant economic damage. The fungus Rhizoctonia solani is among the phytopathogens that cause major harm to the crop, producing symptoms such as damping-off, root rot, hypocotyl rot, leaf blight, and aerial blight. Biological control offers a sustainable alternative by providing antagonism to pathogenic microorganisms. The bioprospecting of bacteria isolated from extreme environments, such as mangroves, has been minimally explored, even though it could improve the chances of finding strains with high biotechnological potential. This study aimed to isolate bacterial from mangrove soils and assess their potential for controlling R. solani AG-1 IA in soybean seeds. Soil samples were collected from the coasts of the Brazilian states of São Paulo and Rio de Janeiro and taken to the laboratory for bacterial isolation. Initially, a screening of the strains was performed in vitro by direct confrontation with R. solani in Petri dishes. Of the 157 bacteria isolated, only five were selected for the in vivo assay, as they showed high levels of inhibition of R. solani AG-1 IA at low concentrations. The efficacy of the strains in controlling R. solani was determined using two inoculation methods: soaking and coating the soybean seeds in the bacterial growth culture. Application of Burkholderia cepacia, and B. glumae by soaking the seeds in bacterial cultures showed better results compared to seed coating, significantly reducing disease severity. In greenhouse conditions, B. cepacia PR10 was more effective in controlling the phytopathogen and also stimulated the development of soybean plants. In conclusion, B. cepacia, and B. glumae emerged as potential antagonists for controlling R. solani AG-1 IA.

The names of two genera and eleven species belonging to Hymenoptera are unavailable. They were published by Francisco Dias da Rocha in 1908 for species from the state of Ceará (Brazil) and attributed to William H. Ashmead. The genus names proposed here as nomina nuda are: Mesopteromalus (Pteromalidae) and Rochai (Ichneumonidae). The species names proposed as nomina nuda are Trichoporus abdominalis, Tetrastichus balteativentris (Eulophidae), Eupelmus myrtaceae (Eupelmidae), Eurytoma cearae (Eurytomidae), Mesopteromalus abdominalis (Pteromalidae), Syntomaspis loranthaceae (Torymidae), Urogaster brasiliensis (Braconidae), Rochai achiaemorpha (Ichneumonidae), Leptacis myrtaceae, Polygnotus brasiliensis, and Synopeas rochai (Platygastridae). The probable relationship between Mesopteromalus abdominalis with Jaliscoa nudipennis Bouček, and between Eurytoma cearae and Rileya cearae Crawford are discussed. KEY WORDS: Ceará; fauna; nomenclatural act; parasitoid wasps; taxonomic catalog

This study investigated the response of arabica coffee plants to the pathogen Pseudomonas coronafaciens pv. garcae using RNA-seq technology. Susceptible and resistant coffee plants were inoculated with the bacteria, and leaf samples were collected at different time points for RNA sequencing. Seven genes related to different defense pathways were chosen for expression quantification in time-course experiments using infected leaves from resistant and susceptible plants, as well as non-infiltrated and water-infiltrated leaves as controls. The results obtained revealed that response mechanisms differ between genotypes and provide insights into the genetic basis of early defense in coffee plants against P. coronafaciens pv. garcae, offering potential strategies for genetic breeding. Key words bacterial halo blight; Coffea arabica ; RNASeq; defense mechanism

The mite Allopsoroptoides galli has been described as a psoroptoidid belonging to the subfamily Psoroptidae. This feather mite was first found in the year 2010, parasitizing hens on an egg farm in the state of São Paulo, Brazil. A phylogenetic investigation on the first DNA sequences of the mite A. galli was conducted. Through the polymerase chain reaction technique, fragments of the 18S and 28S rRNA region were amplified and then sequenced using the Sanger method. The sequences obtained were deposited in GenBank (OK533677 and OK533676). The identity of the amplified DNA fragments was established by entering the sequences obtained into the BLAST software. Listed sequences from GenBank, from both the 18S and the 28S region, were retrieved and aligned to subsequently set up phylogenetic trees, by means of the neighbor-joining (NJ), maximum parsimony (MP), and maximum likelihood (ML) methods. For both sequences obtained experimentally, the search in the GenBank DNA database yielded high similarity only with sequences of the pyroglyphid mite Dermatophagoides farinae. All the phylogenetic trees obtained for 18S rRNA sequences and 28S rRNA sequences presented a high degree of discordance with the current taxonomy. Keywords feather mites; Guira guira ; Psoroptidae

The brown stink bug, Euschistus heros, is considered one of the main pests in Brazil, causing significant damage to several crops. Currently, the principal method of control involves the excessive use of insecticides, leading to the development of resistant populations and environmental contamination. Therefore, it becomes crucial to explore more sustainable control alternatives, with biological agents, particularly entomopathogenic bacteria, emerging as promising due to their proven toxic activity against various insect and insect families. Thus, this study aimed to explore the potential of entomopathogenic bacteria in the control of E. heros. The initial screening of 125 bacteria identified 19 efficient strains, which were tested at 10% concentration under laboratory conditions. Molecular identification was conducted by polymerase chain reaction amplification of the 16S, gyrB, and rpoD genes, followed by sequencing and comparison in EzBioCloud 16S and GenBank. Additionally, the survival rate of E. heros was evaluated at bacterial concentrations of 10, 20, 40, 80, and 100%. Among the isolates tested at 10% concentration, strains 292B3, 457C4, 365BNP6, 742D, 427B, 321B, and Photorhabdus luminescens emerged as the most virulent. Molecular analysis of these strains revealed high similarity to the species Serratia marcescens, Bacillus toyonensis, and Bacillus cereus. The survival rates of E. heros suggested that control efficiency is not solely linked to bacterial concentration, but it also depends on the mechanisms of action and the ability to colonize and interact with the pest. Keywords agricultural pest; hemipteran insect; biocontrol; microbial agents; insecticidal activity

Zebrafish, also known as ‘peixe-zebra’ and ‘Paulistinha’ in Brazil, have been increasingly used for studies in various areas of Medicine and Biology. This fish has several characteristics that make it more suitable for scientific experimentation than other animal models, such as a large number of embryos per mating (about 100 to 200 eggs), a short life cycle (about 2 years), development fast (60 to 90 days to have all organs and systems fully mature), sequenced genome, easy adult breeding, low maintenance cost, transparent eggs and embryos, making it possible to monitor their development. In this qualitative review we discuss the advantages and disadvantages of using the zebrafish model (Danio rerio) in the embryo and adult life stages, considering the principle of the 3 R’s (reduction, replacement and refinement) which are the basis of Bioethics applied to Animal Science Laboratory. Keywords ethical aspects regarding the use of zebrafish; Danio rerio ; experimentation with zebrafish; Laboratory Animal Science

In Brazil, stinking passion flower (Passiflora foetida L.) is exploited as a rootstock for the commercial planting of passion fruit (Passiflora edulis Sims) and also planted for medicinal purposes. Its use as a rootstock is justified by its resistance to Fusarium solani and F. oxysporum f. sp. passiflorae. However, is susceptible to the reniform nematode (Rotylenchulus reniformis) and possible to the Southern root-knot nematode (Meloidogyne incognita). This deserves attention, as plant resistance to diseases caused by soil fungi is often compromised when the roots of these plants are infected by nematodes. The objective of this research was to evaluate the effect of M. incognita on P. foetida. Two trials were carried out in a glasshouse. The first trial comprised three treatments: T1: non-inoculated control; T2: 1,600 M. incognita specimens per plant; T3: 8,000 specimens. For the second trial T2: 5,500; T3: 22,500. Both trials were evaluated 56 days after inoculation. The results showed difference between the inoculated plants and control for the following variables: root weight, vine length, nematodes per gram of roots and reproduction rate. It was concluded that P. foetida is susceptible to M. incognita and infested crop fields should be managed before planting P. foetida.

The world's rich diversity of bats supports healthy ecosystems and important ecosystem services. Maintaining healthy biological systems requires prompt identification of threats to biodiversity and immediate action to protect species, which for wide‐ranging bat species that span geopolitical boundaries warrants international coordination. Anthropogenic forces drive the threats to bats throughout North America and the world. We conducted an international expert elicitation to assess the status of 153 bat species in Canada, the United States, and Mexico. We used expert assessment to determine the conservation status, highest impact threats, and recent population trends for these species. We found that 53% of North American bat species have moderate to very high risk of extinction in the next 15 years. The highest impact threats varied with species and country, and four IUCN threat categories had the greatest overall impacts: Climate Change, Problematic Species (including disease), Agriculture, and Energy Production. Experts estimated that 90% of species assessed had decreasing population trends over the past 15 years, demonstrating the need for conservation action. Although the state of North American bats is concerning, we identify threats that can be addressed through internationally collaborative, proactive, and protective actions to support the recovery and resilience of North American bat species.

Background and Aim Fowl adenovirus (FAdV) is the etiological agent of inclusion body hepatitis (IBH) and hepatitis-hydropericardium syndrome (HHS) in poultry. It is also detected in chickens with runting and stunting syndrome (RSS). FAdV has been detected worldwide, and genotypes 8a, 8b, and 11 have been identified in chickens with enteric problems in Brazil. Nevertheless, none of them have been isolated; therefore, these viruses propagate; thus, the viral behavior and pathogenicity are unknown in Brazil. This study aimed to isolate FAdV from the enteric content of chickens affected by RSS. Materials and Methods Enteric content samples from chickens affected with RSS and a positive polymerase chain reaction (PCR) test for FAdV were inoculated into specific pathogen-free chicken embryonated eggs (CEEs) through the yolk and chorioallantoic membrane routes on 8 and 10 days of age, respectively and the eggs were incubated for five days for viral isolation. Results The embryos exhibited dwarfism, beak atrophy, and pale claws. In addition, some embryos displayed edema and gelatin-like characteristics. The liver exhibited hepatomegaly and multiple necrotic foci, resembling the appearance of nutmeg. In addition, the kidneys appeared enlarged and pale. After 8 days of incubation, the hearts of the inoculated embryos showed hydropericardium. Microscopic evaluation revealed the presence of hepatitis, which was characterized by the presence of intranuclear inclusion bodies and cellular necrosis. Viral FAdV particles were observed in kidney cells using electron microscopy. Viral DNA was detected in the embryos in all three passages, and viral gene copies were also measured in some organs, with high FAdV gene copies detected in the spleen and bursa beyond the liver. Conclusion The molecular characterization of FAdV revealed that the isolated strain belonged to genotype 8a of FAdV. Here, FAdV-8a from chickens infected with RSSs produced IBH/HHS in CEE, and FAdV-8a detected in RSS outbreaks, in addition to producing IBH/HHS in chicken embryos, could be a possible viral agent that causes IBH/HHS in chickens.