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1.
Sci Rep ; 14(1): 15596, 2024 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971939

RESUMO

Common beans (CB), a vital source for high protein content, plays a crucial role in ensuring both nutrition and economic stability in diverse communities, particularly in Africa and Latin America. However, CB cultivation poses a significant threat to diseases that can drastically reduce yield and quality. Detecting these diseases solely based on visual symptoms is challenging, due to the variability across different pathogens and similar symptoms caused by distinct pathogens, further complicating the detection process. Traditional methods relying solely on farmers' ability to detect diseases is inadequate, and while engaging expert pathologists and advanced laboratories is necessary, it can also be resource intensive. To address this challenge, we present a AI-driven system for rapid and cost-effective CB disease detection, leveraging state-of-the-art deep learning and object detection technologies. We utilized an extensive image dataset collected from disease hotspots in Africa and Colombia, focusing on five major diseases: Angular Leaf Spot (ALS), Common Bacterial Blight (CBB), Common Bean Mosaic Virus (CBMV), Bean Rust, and Anthracnose, covering both leaf and pod samples in real-field settings. However, pod images are only available for Angular Leaf Spot disease. The study employed data augmentation techniques and annotation at both whole and micro levels for comprehensive analysis. To train the model, we utilized three advanced YOLO architectures: YOLOv7, YOLOv8, and YOLO-NAS. Particularly for whole leaf annotations, the YOLO-NAS model achieves the highest mAP value of up to 97.9% and a recall of 98.8%, indicating superior detection accuracy. In contrast, for whole pod disease detection, YOLOv7 and YOLOv8 outperformed YOLO-NAS, with mAP values exceeding 95% and 93% recall. However, micro annotation consistently yields lower performance than whole annotation across all disease classes and plant parts, as examined by all YOLO models, highlighting an unexpected discrepancy in detection accuracy. Furthermore, we successfully deployed YOLO-NAS annotation models into an Android app, validating their effectiveness on unseen data from disease hotspots with high classification accuracy (90%). This accomplishment showcases the integration of deep learning into our production pipeline, a process known as DLOps. This innovative approach significantly reduces diagnosis time, enabling farmers to take prompt management interventions. The potential benefits extend beyond rapid diagnosis serving as an early warning system to enhance common bean productivity and quality.


Assuntos
Aprendizado Profundo , Phaseolus , Doenças das Plantas , Phaseolus/virologia , Phaseolus/microbiologia , Doenças das Plantas/virologia , Doenças das Plantas/microbiologia , Agricultura/métodos , Folhas de Planta/virologia , Folhas de Planta/microbiologia , África , Colômbia
2.
Sci Rep ; 11(1): 15730, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344928

RESUMO

Sugarcane yellow leaf (SCYL), caused by the sugarcane yellow leaf virus (SCYLV) is a major disease affecting sugarcane, a leading sugar and energy crop. Despite damages caused by SCYLV, the genetic base of resistance to this virus remains largely unknown. Several methodologies have arisen to identify molecular markers associated with SCYLV resistance, which are crucial for marker-assisted selection and understanding response mechanisms to this virus. We investigated the genetic base of SCYLV resistance using dominant and codominant markers and genotypes of interest for sugarcane breeding. A sugarcane panel inoculated with SCYLV was analyzed for SCYL symptoms, and viral titer was estimated by RT-qPCR. This panel was genotyped with 662 dominant markers and 70,888 SNPs and indels with allele proportion information. We used polyploid-adapted genome-wide association analyses and machine-learning algorithms coupled with feature selection methods to establish marker-trait associations. While each approach identified unique marker sets associated with phenotypes, convergences were observed between them and demonstrated their complementarity. Lastly, we annotated these markers, identifying genes encoding emblematic participants in virus resistance mechanisms and previously unreported candidates involved in viral responses. Our approach could accelerate sugarcane breeding targeting SCYLV resistance and facilitate studies on biological processes leading to this trait.


Assuntos
Resistência à Doença/genética , Genoma de Planta , Estudo de Associação Genômica Ampla , Luteoviridae/fisiologia , Doenças das Plantas/genética , Proteínas de Plantas/genética , Saccharum/genética , Cromossomos de Plantas/genética , Resistência à Doença/imunologia , Regulação da Expressão Gênica de Plantas , Genótipo , Filogenia , Melhoramento Vegetal , Doenças das Plantas/virologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/virologia , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas , Saccharum/crescimento & desenvolvimento , Saccharum/virologia
3.
Arch Virol ; 166(10): 2865-2868, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34292374

RESUMO

A putative new virus with sequence similarity to members of the genus Cavemovirus in the family Caulimoviridae was identified in wild chicory (Cichorium intybus) by next-generation sequencing (NGS). The putative new virus was tentatively named "chicory mosaic cavemovirus" (ChiMV), and its genome was determined to be 7,775 nucleotides (nt) long with the typical genome organization of cavemoviruses. ORF1 encodes a putative coat protein/movement polyprotein (1,278 aa), ORF2 encodes a putative replicase (650 aa), and ORF3 encodes a putative transactivator factor (384 aa). The first two putative proteins have 46.2% and 68.7% amino acid sequence identity to the CP/MP protein (YP_004347414) and replicase (YP_004347415), respectively, of sweet potato collusive virus (SPCV). ORF3 encodes a protein with 38.5% amino acid sequence identity to the putative transactivator factor (NP_056849) of cassava vein mosaic virus (CsVMV). The new putative viral genome and those of three cavemoviruses (epiphyllum virus 4 [EpV-4], SPCV, and CsVMV) differ by 24-27% in the nt sequence of the replicase gene, which exceeds the species demarcation cutoff (>20%) for the family.


Assuntos
Caulimoviridae/genética , Cichorium intybus/virologia , Sequência de Aminoácidos , Caulimoviridae/classificação , Genoma Viral/genética , Fases de Leitura Aberta/genética , Filogenia , Doenças das Plantas/virologia , Folhas de Planta/virologia , RNA Viral/genética , Especificidade da Espécie , Proteínas Virais/genética
4.
Arch Virol ; 166(9): 2419-2434, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34132915

RESUMO

Passion fruit woodiness disease (PWD), caused by cowpea aphid-borne mosaic virus (CABMV), produces socioeconomic problems in Brazil. The objectives of this study were to i) evaluate the temporal progression of PWD, ii) identify Passiflora genotypes with resistance to CABMV, and iii) detect virus infection in asymptomatic plants by reverse transcription quantitative polymerase chain reaction (RT-qPCR) in cases where standard RT-PCR detection failed. The experiment was conducted in a greenhouse using 128 genotypes belonging to 12 species and three hybrids (inter- and intraspecific) of Passiflora, evaluated at five time points after inoculation. Progression rates and disease severity were lower in P. cincinnata, P. gibertii, P. miersii, and P. mucronata than in P. edulis, P. alata, Passiflora sp., and hybrids. Of the genotypes tested, 20.31% were resistant, especially the accessions of P. suberosa, P. malacophylla, P. setacea, P. pohlii, and P. bahiensis, which remained asymptomatic throughout the experiment. The absence of symptoms does not imply immunity of plants to the virus, since RT-qPCR analysis confirmed infection by the virus in asymptomatic plants of P. cincinnata, P. gibertii, P. miersii, P. mucronata, P. setacea, P. malacophylla, and P. suberosa. Even after four inoculations, the virus was not detected by RT-qPCR in the upper leaves in plants of the species P. pohlii and P. bahiensis, indicating that these species are probably immune to CABMV.


Assuntos
Passiflora/imunologia , Doenças das Plantas/imunologia , Potyvirus/imunologia , Brasil , Genótipo , Passiflora/classificação , Passiflora/virologia , Doenças das Plantas/virologia , Folhas de Planta/virologia , Potyvirus/genética , Potyvirus/isolamento & purificação , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença
5.
J Gen Virol ; 102(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34097597

RESUMO

Potato yellow vein virus (PYVV) was detected in potatoes grown in the Central highlands, north of Bogotá (~3000 m altitude), Colombia. At this altitude viral whitefly vectors are largely absent, but infection persists because of the use of uncertified tubers. Plants with typical PYVV-induced yellowing symptoms, as well as with atypical yellowing or non-symptomatic symptoms were sampled at three separate geographical locations. PYVV presence was assessed by RT-PCR, and several plants were subjected to high-throughput sequencing (HTS) of their small RNA (sRNA) populations. Complete or almost complete sequences of four PYVV isolates were thus reconstructed, all from symptomatic plants. Three viral isolates infected plants singly, while the fourth co-infected the plant together with a potyvirus. Relative proportions of sRNAs to each of the three crinivirus genomic RNAs were found to remain comparable among the four infections. Genomic regions were identified as hotspots of sRNA formation, or as regions that poorly induced sRNAs. Furthermore, PYVV titres in the mixed versus single infections remained comparable, indicating an absence of synergistic/antagonistic effects of the potyvirus on the accumulation of PYVV. Daughter plants raised in the greenhouse from tubers of the infected, field-sampled plants displayed mild PYVV infection symptoms that disappeared with time, demonstrating the occurrence of recovery and asymptomatic infection phenotypes in this pathosystem.


Assuntos
Crinivirus/genética , Crinivirus/isolamento & purificação , Genoma Viral , Doenças das Plantas/virologia , Solanum tuberosum/virologia , Colômbia , Folhas de Planta/virologia , Tubérculos/virologia , Potyvirus , RNA Viral/análise , RNA Viral/genética
6.
Arch Virol ; 166(6): 1691-1709, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33852083

RESUMO

Geminiviruses have genomes composed of single-stranded DNA molecules and encode a rolling-circle replication (RCR) initiation protein ("Rep"), which has multiple functions. Rep binds to specific repeated DNA motifs ("iterons"), which are major determinants of virus-specific replication. The particular amino acid (aa) residues that determine the preference of a geminivirus Rep for specific iterons (i.e., the trans-acting replication "specificity determinants", or SPDs) are largely unknown, but diverse lines of evidence indicate that most of them are closely associated with the so-called RCR motif I (FLTYP), located in the first 12-19 aa residues of the protein. In this work, we characterized two strains of a novel begomovirus, rhynchosia golden mosaic Sinaloa virus (RhGMSV), that were incompatible in replication in pseudorecombination experiments. Systematic comparisons of the Rep proteins of both RhGMSV strains in the DNA-binding domain allowed the aa residues at positions 71 and 74 to be identified as the residues most likely to be responsible for differences in replication specificity. Residue 71 is part of the ß-5 strand structural element, which was predicted in previous studies to contain Rep SPDs. Since the Rep proteins encoded by both RhGMSV strains are identical in their first 24 aa residues, where other studies have mapped potential SPDs, this is the first study lending direct support to the notion that geminivirus Rep proteins contain separate SPDs in their N-terminal domain.


Assuntos
Begomovirus/classificação , Begomovirus/metabolismo , Proteínas Virais/metabolismo , Replicação Viral/fisiologia , Sequência de Aminoácidos , Begomovirus/genética , Clonagem Molecular , Fabaceae/virologia , Genoma Viral , Filogenia , Folhas de Planta/virologia , Conformação Proteica , Vírus Reordenados , Nicotiana/virologia , Proteínas Virais/genética , Replicação Viral/genética
7.
Arch Virol ; 166(6): 1615-1622, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33774730

RESUMO

We identified a novel plant rhabdovirus infecting native joá (Solanum aculeatissimum) plants in Brazil. Infected plants showed yellow blotches on the leaves, and typical enveloped bacilliform rhabdovirus particles associated with the nucleus were seen in thin sections by electron microscopy. The virus could be graft-transmitted to healthy joá and tomato plants but was not mechanically transmissible. RT-PCR using degenerate plant rhabdovirus L gene primers yielded an amplicon from extracted total RNA, the sequence of which was similar to those of alphanucleorhabdoviruses. Based on close sequence matches, especially with the type member potato yellow dwarf virus (PYDV), we adopted a degenerate-primer-walking strategy towards both genome ends. The complete genome of joá yellow blotch-associated virus (JYBaV) is comprised of 12,965 nucleotides, is less than 75% identical to that of its closest relative PYDV, and clusters with PYDV and other alphanucleorhabdoviruses in L protein phylogenetic trees, suggesting that it should be taxonomically classified in a new species in the genus Alphanucleorhabdovirus, family Rhabdoviridae. The genome organization of JYBaV is typical of the 'PYDV-like' subgroup of alphanucleorhabdoviruses, with seven genes (N-X-P-Y-M-G-L) separated by conserved intergenic regions and flanked by partly complementary 3' leader and 5' trailer regions.


Assuntos
Doenças das Plantas/virologia , Rhabdoviridae/isolamento & purificação , Solanum/virologia , Brasil , Genoma Viral , Filogenia , Folhas de Planta/virologia , Vírus de Plantas , Rhabdoviridae/genética
8.
Arch Virol ; 166(5): 1409-1414, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33646405

RESUMO

Common bean plants (Phaseolus vulgaris L.) showing different virus-like symptoms were collected in northwestern Argentina. Dot-blot hybridization tests showed that the begomoviruses bean golden mosaic virus and tomato yellow vein streak virus were the most prevalent, but they also revealed the presence of unknown begomoviruses. The complete genome sequence of one of these unknown begomoviruses was determined. Sequence analysis showed that the virus is a typical New World begomovirus, for which the name "bean bushy stunt virus" (BBSV) is proposed. Biological assays based on biolistic inoculations showed that BBSV induced leaf roll and stunting symptoms similar to those observed in the field-collected common bean sample.


Assuntos
Begomovirus/fisiologia , Phaseolus/virologia , Doenças das Plantas/virologia , Argentina , Sequência de Bases , Begomovirus/classificação , Begomovirus/genética , Begomovirus/patogenicidade , DNA Viral/genética , Genoma Viral/genética , Especificidade de Hospedeiro , Fases de Leitura Aberta , Phaseolus/crescimento & desenvolvimento , Filogenia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/virologia , Glycine max/crescimento & desenvolvimento , Glycine max/virologia
9.
PLoS One ; 15(11): e0242887, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33237955

RESUMO

Natural elicitors derived from pathogenic microorganisms represent an ecologic strategy to achieve resistance in plants against diseases. Glucosylceramides (GlcCer) are classified as neutral glycosphingolipids. GlcCer were isolated and purified from Fusarium oxysporum mycelium. F. oxysporum is a plant pathogenic fungus, abundant in soil and causing severe losses in economically important crops such as corn, tobacco, banana, cotton and passion fruit. In this study we evaluate the capacity of GlcCer in inducing resistance in N. tabacum cv Xanthi plants against Tobacco mosaic virus (TMV). Spraying tobacco plants with GlcCer before virus infection reduced the incidence of necrotic lesions caused by TMV. In addition, plants already infected with the virus showed a reduction in hypersensitive response (HR) lesions after GlcCer treatment, suggesting an antiviral effect of GlcCer. Our investigations showed that GlcCer stimulates the early accumulation of H2O2 and superoxide radicals. In addition, the expression of PR-1 (pathogenesis-related 1, with suggested antifungal action), PR-2 (ß-1,3-glucanase), PR-3 (Chitinase), PR-5 (Osmotin), PAL (Phenylalanine ammonia-lyase), LOX (Lipoxygenase) and POX (Peroxidase) genes was highly induced after treatment of tobacco plants with GlcCer and induction levels remained high throughout a period of 6 to 120 hours. Our experiments demonstrate that GlcCer induces resistance in tobacco plants against infection by TMV.


Assuntos
Antivirais/farmacologia , Fusarium/química , Doenças das Plantas/prevenção & controle , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Antivirais/química , Glucosilceramidas , Peróxido de Hidrogênio/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/virologia , Superóxidos/química , Nicotiana/efeitos dos fármacos , Nicotiana/virologia , Vírus do Mosaico do Tabaco/patogenicidade
10.
Viruses ; 12(9)2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32942623

RESUMO

The knowledge of genomic data of new plant viruses is increasing exponentially; however, some aspects of their biology, such as vectors and host range, remain mostly unknown. This information is crucial for the understanding of virus-plant interactions, control strategies, and mechanisms to prevent outbreaks. Typically, rhabdoviruses infect monocot and dicot plants and are vectored in nature by hemipteran sap-sucking insects, including aphids, leafhoppers, and planthoppers. However, several strains of a potentially whitefly-transmitted virus, papaya cytorhabdovirus, were recently described: (i) bean-associated cytorhabdovirus (BaCV) in Brazil, (ii) papaya virus E (PpVE) in Ecuador, and (iii) citrus-associated rhabdovirus (CiaRV) in China. Here, we examine the potential of the Bemisia tabaci Middle East-Asia Minor 1 (MEAM1) to transmit BaCV, its morphological and cytopathological characteristics, and assess the incidence of BaCV across bean producing areas in Brazil. Our results show that BaCV is efficiently transmitted, in experimental conditions, by B. tabaci MEAM1 to bean cultivars, and with lower efficiency to cowpea and soybean. Moreover, we detected BaCV RNA in viruliferous whiteflies but we were unable to visualize viral particles or viroplasm in the whitefly tissues. BaCV could not be singly isolated for pathogenicity tests, identification of the induced symptoms, and the transmission assay. BaCV was detected in five out of the seven states in Brazil included in our study, suggesting that it is widely distributed throughout bean producing areas in the country. This is the first report of a whitefly-transmitted rhabdovirus.


Assuntos
Hemípteros/virologia , Doenças das Plantas/virologia , Infecções por Rhabdoviridae/transmissão , Infecções por Rhabdoviridae/virologia , Rhabdoviridae/isolamento & purificação , Animais , Evolução Biológica , Brasil , Carica/virologia , China , Equador , Genômica , Oriente Médio , Folhas de Planta/virologia , Vírus de Plantas , Plantas/virologia , Rhabdoviridae/classificação , Rhabdoviridae/genética , Análise de Sequência
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