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1.
Neotrop Entomol ; 53(3): 461-468, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38656593

RESUMO

We report the first record of the occurrence of the banana weevil, Cosmopolites sordidus (Germar, 1823) (Coleoptera: Curculionidae), an economically important pest of bananas (Musa spp.), from Fifa Mountains in Saudi Arabia. Moreover, we recorded the first observation of damage caused to bananas by C. sordidus in a banana farm in Jazan Province, southwestern Saudi Arabia, in March 2022. Molecular characterization using DNA sequences of the mitochondrial COI gene confirmed the morphological identification of C. sordidus. This discovery is considered a warning notice to prevent the potential establishment and spread of this dangerous pest in the banana cultivation regions in Saudi Arabia. Therefore, it is recommended that detection and monitoring of banana weevil should be undertaken in Saudi banana farms in order to restrict the dissemination of this weevil to other banana cultivation areas.


Assuntos
Musa , Gorgulhos , Animais , Gorgulhos/classificação , Arábia Saudita , Musa/parasitologia , Feminino , Masculino
2.
Gene ; 809: 146041, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34710526

RESUMO

Plant immunity to pathogen infections is a dynamic response that involves multiple organelles and defence signalling systems such as hypersensitive response (HR) and systemic acquired resistance (SAR). The latter requires the function of Pathogenesis-related (PR) proteins, a common plant protein family with diverse roles in plant innate immunity. Our previous proteomics study showed that a PR gene (ITC1587_Bchr9_P26466_MUSBA) was differentially regulated during a compatible banana-M. incognita interaction, substantiating the isolation of this gene in the current study. Here, we successfully isolated and characterised Pathogenesis-related-10 (PR10) gene with ß-1,3-glucanase and ribonuclease (RNase) activities from two Musa acuminata cultivars (denoted as MaPR10) namely Berangan and Grand Naine (ITC1256). We found that MaPR10 cloned sequences possess glycine-rich loop domain and shared conserved motifs specific to PR10 gene group, confirming its identity as a member of this group. Interestingly, we also found a catalytic domain sequence for glycoside hydrolase family 16 (EXDXXE), unique only to MaPR10 cloned sequences. Two peptide variants closely related to the reference sequence ITC1587_Bchr9_P26466_MUSBA namely MaPR10-BeB5 and MaPR10-GNA5 were overexpressed and purified to test for their functionality. Here, we confirmed that both protein variants possess ß-1,3-glucanase and ribonuclease (RNase) activities, and inhibit the growth of Aspergillus fumigatus, a human opportunistic pathogen. To our knowledge, this is the first PR10 plant proteins with such properties to be reported thus far.


Assuntos
Musa/genética , Musa/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tylenchoidea/patogenicidade , Animais , Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Parasita/genética , Cebolas/genética , Filogenia , Imunidade Vegetal/genética , Proteínas de Plantas/farmacologia , Raízes de Plantas/genética , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas
3.
J Agric Food Chem ; 68(24): 6502-6510, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32463695

RESUMO

Banana plants (Musa spp.) are susceptible to infection by many plant-parasitic nematodes, including Meloidogyne incognita. In this study, a mixed fermentation broth of chicken manure (CM) and cassava ethanol wastewater (CEW) was used to inhibit M. incognita by reducing egg hatching and by having a lethal effect on second-stage juvenile nematodes (J2s). It also alleviated nematode damage and promoted banana plant growth. Using gas chromatography-mass spectrometry (GC-MS), we identified methyl palmitate and methyl stearate as bioactive compounds. These bioactive compounds repelled J2s and inhibited egg hatching; reduced root galls, egg masses, and nematodes in soil; and downregulated the essential parasitic nematode genes Mi-flp-18 and 16D10. A Caenorhabditis elegans offspring assay showed that low concentrations of the fermentation broth, methyl palmitate, and methyl stearate were safe for its life cycle. This study explored the effective and environmentally safe strategies for controlling root-knot nematodes.


Assuntos
Antinematódeos/farmacologia , Musa/parasitologia , Palmitatos/farmacologia , Doenças das Plantas/parasitologia , Estearatos/farmacologia , Tylenchoidea/efeitos dos fármacos , Animais , Antinematódeos/química , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Palmitatos/química , Raízes de Plantas/parasitologia , Estearatos/química , Tylenchoidea/crescimento & desenvolvimento
4.
Math Biosci ; 322: 108324, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32092468

RESUMO

We study the infestation dynamics of banana or plantain plants by Radopholus similis, a plant-parasitic nematode that causes severe damages. Two control strategies are implemented in our model: pesticides, which are widely used, and fallows, which are more environmentally friendly. To represent the host-parasite dynamics, two semi-discrete models are proposed. During each cropping season, free nematodes enter the plant roots, on which they feed and reproduce. At the end of the cropping season, fruits are harvested. In the first model, the parent plant is cut down to be replaced by one of its suckers and pesticides are applied. In the second model, the parent plant is uprooted and a fallow period is introduced, inducing the decay of the free pest populations; at the beginning of the next cropping season, a pest-free vitroplant is planted. For both models, the effective reproduction number of pests is computed, assuming that the infestation dynamics are fast compared to the other processes, which leads to the model order reduction. Conditions on the pesticide load or the fallow duration are then derived to ensure the stability of the periodic pest free solution. Finally, numerical simulations illustrate these theoretical results.


Assuntos
Proteção de Cultivos , Modelos Biológicos , Musa/parasitologia , Nematoides , Controle de Pragas , Raízes de Plantas/parasitologia , Animais , Proteção de Cultivos/métodos , Controle de Pragas/métodos
5.
Micron ; 125: 102729, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31386982

RESUMO

The primary concern of this research is to perform a microscopic analysis of the natural wax covering banana skipper caterpillar. The scanning electron microscopic (SEM) analysis shows that the wax exhibits an unprecedented microtubular form, consisting of carbon and oxygen as main elements as revealed by energy dispersive X-ray (EDX) analysis. The Fourier Transform Infra-Red (FTIR) spectroscopic analysis, which reveals the presence of peaks at 2914, 2890, 1469, and 722 cm-1 and the absence of peaks around 1700 cm-1, indicates that the analyzed natural wax is a polyethylene wax without the CO functional group.


Assuntos
Borboletas/ultraestrutura , Musa/parasitologia , Folhas de Planta/parasitologia , Ceras/metabolismo , Animais , Carbono/análise , Microscopia Eletrônica de Varredura , Oxigênio/análise , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Ceras/química
6.
Molecules ; 24(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340442

RESUMO

In recent years, there has been an increase in pesticide use to improve crop production due to the growth of agricultural activities. Consequently, various pesticides have been present in the environment for an extended period of time. This review presents a general description of recent advances in the development of methods for the quantification of pesticides used in agricultural activities. Current advances focus on improving sensitivity and selectivity through the use of nanomaterials in both sensor assemblies and new biosensors. In this study, we summarize the electrochemical, optical, nano-colorimetric, piezoelectric, chemo-luminescent and fluorescent techniques related to the determination of agricultural pesticides. A brief description of each method and its applications, detection limit, purpose-which is to efficiently determine pesticides-cost and precision are considered. The main crops that are assessed in this study are bananas, although other fruits and vegetables contaminated with pesticides are also mentioned. While many studies have assessed biosensors for the determination of pesticides, the research in this area needs to be expanded to allow for a balance between agricultural activities and environmental protection.


Assuntos
Técnicas Biossensoriais/métodos , Colorimetria/métodos , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Praguicidas/isolamento & purificação , Espectrometria de Fluorescência/métodos , Agricultura , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/instrumentação , Colorimetria/economia , Colorimetria/instrumentação , Conservação dos Recursos Naturais/métodos , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/microbiologia , Produtos Agrícolas/parasitologia , Produtos Agrícolas/virologia , Técnicas Eletroquímicas/economia , Técnicas Eletroquímicas/instrumentação , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Humanos , Limite de Detecção , Medições Luminescentes/economia , Medições Luminescentes/instrumentação , Musa/efeitos dos fármacos , Musa/microbiologia , Musa/parasitologia , Musa/virologia , Espectrometria de Fluorescência/economia , Espectrometria de Fluorescência/instrumentação
7.
Bull Entomol Res ; 109(5): 649-658, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30806341

RESUMO

Parasitoids, released in augmentative biological control programmes, which display a rapid host-location capacity, have a higher likelihood of successfully controlling target pest species. By learning to associate sensory cues to a suitable oviposition site, might parasitoids used as biological control agents, locate hosts more rapidly, and perhaps increase the efficacity of e.g. Tephritidae fruit fly management. We studied associative learning of Fopius arisanus (Hymenoptera: Braconidae) and tested its range of learning in natural and conditional hosts and host fruits, i.e. Bactrocera dorsalis, Zeugodacus cucurbitae, Ceratitis capitata and Ceratitis cosyra (Diptera: Tephritidae) and on fruits (papaya, tomato, banana). Naïve female F. arisanus were compared with experienced wasps, which had been offered infested and non-infested fruit, and been allowed to oviposit. Preferences for olfactory cues from infested fruits were thereafter assessed in a two-choice olfactometer. Naïve and trained parasitoids preference differed in general and non-responders to infested fruits were higher among naïve parasitoids. The trained wasps preferred the fruit infested in the training more than the control fruit, for all combination, except when C. cosyra infested the fruits, hence avoidance behavioural response was observed towards the odour of the infested fruit. Fopius arisanus was capable of behaviourally respond to the learned information, e.g. associative odour learning was achieved, yet limited depending on interaction level, fruit fly and fruit combination. To create F. arisanus preference of an associated odour, it might hence be needed to ensure oviposition in perceived suitable host and host fruit, for the parasitoid learning to become favourable in a biological control setup.


Assuntos
Aprendizagem por Associação , Frutas/parasitologia , Tephritidae/parasitologia , Vespas/fisiologia , Animais , Carica/parasitologia , Comportamento de Escolha , Feminino , Especificidade de Hospedeiro , Solanum lycopersicum/parasitologia , Musa/parasitologia , Olfatometria , Oviposição/fisiologia , Controle Biológico de Vetores/métodos
8.
PLoS One ; 13(8): e0202199, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30096210

RESUMO

The abundance of banana flower thrips (Thrips hawaiiensis Morgan) in a banana (Musa acuminata Colla "Williams" cultivar) plantation was investigated using yellow sticky traps (29.70 cm × 21.00 cm) in 2015. Banana flower thrips occurred throughout the year with monthly variation, and the maximum occurrence was observed in October and November during the bud burst (73.80 ± 6.32 adults/trap) and young fruit (70.06 ± 5.69 adults/trap) periods. The damage rates were as follows: interior flowers >3rd-layer flowers > 2nd-layer flowers > 1st-layer flowers > young fruits. This result indicates that thrips migrated to lower bracts, young fruits, and other flower buds as bracts gradually opened. Results also showed that the reducing sugar, vitamin C, protein and ash contents in thrips-damaged flowers were all significantly lower than those in undamaged flowers, while there was no significant difference between damaged and undamaged young banana fruit. Our results indicated that the abundances of banana flower thrips were closely associated with the growing stage of banana. Thrips mainly infested flower buds and caused a reduction in nutrients for the host plant, especially the reducing sugar and vitamin C contents, which reduced the nutritional quality of banana fruits and the quality of flower bud by-products of banana.


Assuntos
Musa/metabolismo , Musa/parasitologia , Tisanópteros/patogenicidade , Animais , Ácido Ascórbico/análise , China , Flores/química , Flores/crescimento & desenvolvimento , Frutas/química , Interações Hospedeiro-Patógeno , Humanos , Controle de Insetos , Musa/crescimento & desenvolvimento , Valor Nutritivo , Proteínas de Vegetais Comestíveis/análise , Dinâmica Populacional , Açúcares/análise
9.
Plant Biotechnol J ; 16(2): 520-529, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28703405

RESUMO

Double-stranded RNA (dsRNA) molecules targeting two genes have been identified that suppress economically important parasitic nematode species of banana. Proteasomal alpha subunit 4 (pas-4) and Actin-4 (act-4) were identified from a survey of sequence databases and cloned sequences for genes conserved across four pests of banana, Radopholus similis, Pratylenchus coffeae, Meloidogyne incognita and Helicotylenchus multicinctus. These four species were targeted with dsRNAs containing exact 21 nucleotide matches to the conserved regions. Potential off-target effects were limited by comparison with Caenorhabditis, Drosophila, rat, rice and Arabidopsis genomes. In vitro act-4 dsRNA treatment of R. similis suppressed target gene expression by 2.3-fold, nematode locomotion by 66 ± 4% and nematode multiplication on carrot discs by 49 ± 5%. The best transgenic carrot hairy root lines expressing act-4 or pas-4 dsRNA reduced transcript message abundance of target genes in R. similis by 7.9-fold and fourfold and nematode multiplication by 94 ± 2% and 69 ± 3%, respectively. The same act-4 and pas-4 lines reduced P. coffeae target transcripts by 1.7- and twofold and multiplication by 50 ± 6% and 73 ± 8%. Multiplication of M. incognita on the pas-4 lines was reduced by 97 ± 1% and 99 ± 1% while target transcript abundance was suppressed 4.9- and 5.6-fold. There was no detectable RNAi effect on nontarget nematodes exposed to dsRNAs targeting parasitic nematodes. This work defines a framework for development of a range of nonprotein defences to provide broad resistance to pests and pathogens of crops.


Assuntos
Musa/parasitologia , Animais , Produtos Agrícolas/genética , Produtos Agrícolas/parasitologia , Musa/genética , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Interferência de RNA , Tylenchoidea/patogenicidade
10.
PLoS One ; 12(7): e0181384, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28750003

RESUMO

Chrysodeixis chalcites, an important pest of banana crops on the Canary Islands, is usually controlled by chemical insecticides. The present study aimed to evaluate the efficacy of the most prevalent isolate of the Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV, Baculoviridae) as a biological insecticide. Overall the prevalence of ChchNPV infection in C. chalcites populations was 2.3% (103 infected larvae out of 4,438 sampled), but varied from 0-4.8% on Tenerife and was usually low (0-2%) on the other islands. On Tenerife, infected larvae were present at 11 out of 17 plantations sampled. The prevalence of infection in larvae on bananas grown under greenhouse structures was significantly higher (3%) than in open-field sites (1.4%). The ChchNPV-TF1 isolate was the most abundant and widespread of four genetic variants of the virus. Application of 1.0x109 viral occlusion bodies (OBs)/l of ChchNPV-TF1 significantly reduced C. chalcites foliar damage in young banana plants as did commonly used pesticides, both in greenhouse and open-field sites. The insecticidal efficacy of ChchNPV-TF1 was similar to that of indoxacarb and a Bacillus thuringiensis (Bt)-based insecticide in one year of trials and similar to Bt in the following year of trails in greenhouse and field crops. However, larvae collected at different time intervals following virus treatments and reared in the laboratory experienced 2-7 fold more mortality than insects from conventional insecticide treatments. This suggests that the acquisition of lethal dose occurred over an extended period (up to 7 days) compared to a brief peak in larvae on plants treated with conventional insecticides. These results should prove useful for the registration of a ChchNPV-based insecticide for integrated management of this pest in banana crops on the Canary Islands.


Assuntos
Inseticidas/metabolismo , Mariposas/virologia , Musa/parasitologia , Nucleopoliedrovírus/fisiologia , Controle Biológico de Vetores , Animais , Larva/virologia , Doenças das Plantas/parasitologia , Folhas de Planta/parasitologia , Espanha
11.
PLoS One ; 12(6): e0178438, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28575037

RESUMO

With a diverse host range, Meloidogyne incognita (root-knot nematode) is listed as one of the most economically important obligate parasites of agriculture. This nematode species establishes permanent feeding sites in plant root systems soon after infestation. A compatible host-nematode interaction triggers a cascade of morphological and physiological process disruptions of the host, leading to pathogenesis. Such disruption is reflected by altered gene expression in affected cells, detectable using molecular approaches. We employed a high-throughput proteomics approach to elucidate the events involved in a compatible banana- M. incognita interaction. This study serves as the first crucial step in developing natural banana resistance for the purpose of biological-based nematode management programme. We successfully profiled 114 Grand naine root proteins involved in the interaction with M. incognita at the 30th- and 60th- day after inoculation (dai). The abundance of proteins involved in fundamental biological processes, cellular component organisation and stress responses were significantly altered in inoculated root samples. In addition, the abundance of proteins in pathways associated with defence and giant cell maintenance in plants such as phenylpropanoid biosynthesis, glycolysis and citrate cycle were also implicated by the infestation.


Assuntos
Musa/parasitologia , Proteoma , Tylenchoidea/fisiologia , Animais , Cromatografia Líquida , Ensaios de Triagem em Larga Escala , Espectrometria de Massas em Tandem
12.
Ann Bot ; 119(5): 915-930, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28130221

RESUMO

Background and Aims: Endoparasitic root-knot nematodes (RKNs) ( Meloidogyne spp.) cause considerable losses in banana ( Musa spp.), with Meloidogyne incognita a predominant species in Cavendish sub-group bananas. This study investigates the root transcriptome in Musa acuminata genotypes 4297-06 (AA) and Cavendish Grande Naine (CAV; AAA) during early compatible interactions with M. incognita . Methods: Roots were analysed by brightfield light microscopy over a 35 d period to examine nematode penetration and morphological cell transformation. RNA samples were extracted 3, 7 and 10 days after inoculation (DAI) with nematode J2 juveniles, and cDNA libraries were sequenced using lllumina HiSeq technology. Sequences were mapped to the M. acuminata ssp. malaccensis var. Pahang genome sequence, differentially expressed genes (DEGs) identified and transcript representation determined by gene set enrichment and pathway mapping. Key Results: Microscopic analysis revealed a life cycle of M. incognita completing in 24 d in CAV and 27 d in 4279-06. Comparable numbers of DEGs were up- and downregulated in each genotype, with potential involvement of many in early host defence responses involving reactive oxygen species and jasmonate/ethylene signalling. DEGs revealed concomitant auxin metabolism and cell wall modification processes likely to be involved in giant cell formation. Notable transcripts related to host defence included those coding for leucine-rich repeat receptor-like serine/threonine-protein kinases, peroxidases, thaumatin-like pathogenesis-related proteins, and DREB, ERF, MYB, NAC and WRKY transcription factors. Transcripts related to giant cell development included indole acetic acid-amido synthetase GH3.8 genes, involved in auxin metabolism, as well as genes encoding expansins and hydrolases, involved in cell wall modification. Conclusions: Expression analysis in M. acuminata during compatible interactions with RKNs provides insights into genes modulated during infection and giant cell formation. Increased understanding of both defence responses to limit parasitism during compatible interactions and effector-targeted host genes in this complex interaction will facilitate the development of genetic improvement measures for RKNs.


Assuntos
Musa/genética , Musa/parasitologia , Doenças das Plantas/genética , Transcriptoma , Tylenchoidea/fisiologia , Animais , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
13.
PLoS One ; 11(9): e0162013, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27603787

RESUMO

The WRKY family of transcription factors orchestrate the reprogrammed expression of the complex network of defense genes at various biotic and abiotic stresses. Within the last 96 million years, three rounds of Musa polyploidization events had occurred from selective pressure causing duplication of MusaWRKYs with new activities. Here, we identified a total of 153 WRKY transcription factors available from the DH Pahang genome. Based on their phylogenetic relationship, the MusaWRKYs available with complete gene sequence were classified into the seven common WRKY sub-groups. Synteny analyses data revealed paralogous relationships, with 17 MusaWRKY gene pairs originating from the duplication events that had occurred within the Musa lineage. We also found 15 other MusaWRKY gene pairs originating from much older duplication events that had occurred along Arecales and Poales lineage of commelinids. Based on the synonymous and nonsynonymous substitution rates, the fate of duplicated MusaWRKY genes was predicted to have undergone sub-functionalization in which the duplicated gene copies retain a subset of the ancestral gene function. Also, to understand the regulatory roles of MusaWRKY during a biotic stress, Illumina sequencing was performed on resistant and susceptible cultivars during the infection of root lesion nematode, Pratylenchus coffeae. The differential WRKY gene expression analysis in nematode resistant and susceptible cultivars during challenged and unchallenged conditions had distinguished: 1) MusaWRKYs participating in general banana defense mechanism against P.coffeae common to both susceptible and resistant cultivars, 2) MusaWRKYs that may aid in the pathogen survival as suppressors of plant triggered immunity, 3) MusaWRKYs that may aid in the host defense as activators of plant triggered immunity and 4) cultivar specific MusaWRKY regulation. Mainly, MusaWRKY52, -69 and -92 are found to be P.coffeae specific and can act as activators or repressors in a defense pathway. Overall, this preliminary study in Musa provides the basis for understanding the evolution and regulatory mechanism of MusaWRKY during nematode stress.


Assuntos
Resistência à Doença/genética , Musa/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Animais , Regulação da Expressão Gênica de Plantas , Família Multigênica/genética , Musa/parasitologia , Nematoides/patogenicidade , Doenças das Plantas/parasitologia , Proteínas de Plantas/biossíntese , Raízes de Plantas/genética , Raízes de Plantas/parasitologia
14.
PLoS One ; 10(4): e0119700, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25849382

RESUMO

Suppression of root-knot nematodes is crucially important for maintaining the worldwide development of the banana industry. Growing concerns about human and environmental safety have led to the withdrawal of commonly used nematicides and soil fumigants, thus motivating the development of alternative nematode management strategies. In this study, Meloidogyne javanica was isolated, and the nematicidal effect of Camellia seed cake on this pest was investigated. The results showed that in dish experiments, Camellia seed cake extracts under low concentration (2 g/L) showed a strong nematicidal effect. After treatment for 72 h, the eggs of M. javanica were gradually dissolved, and the intestine of the juveniles gradually became indistinct. Nematicidal compounds, including saponins identified by HPLC-ESI-MS and 8 types of volatile compounds identified by GC-MS, exhibited effective nematicidal activities, especially 4-methylphenol. The pot experiments demonstrated that the application of Camellia seed cake suppressed M. javanica, and promoted the banana plant growth. This study explored an effective nematicidal agent for application in soil and revealed its potential mechanism of nematode suppression.


Assuntos
Antinematódeos/farmacologia , Camellia/química , Doenças das Plantas/prevenção & controle , Saponinas/farmacologia , Infecções por Secernentea/prevenção & controle , Sementes/química , Tylenchoidea/efeitos dos fármacos , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Musa/parasitologia , Controle Biológico de Vetores , Doenças das Plantas/parasitologia , Extratos Vegetais/farmacologia , Raízes de Plantas/parasitologia , Saponinas/isolamento & purificação , Infecções por Secernentea/parasitologia , Espectrometria de Massas por Ionização por Electrospray
15.
Adv Virus Res ; 91: 229-69, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25591881

RESUMO

Banana and plantain (Musa spp.), produced in 10.3 million ha in the tropics, are among the world's top 10 food crops. They are vegetatively propagated using suckers or tissue culture plants and grown almost as perennial plantations. These are prone to the accumulation of pests and pathogens, especially viruses which contribute to yield reduction and are also barriers to the international exchange of germplasm. The most economically important viruses of banana and plantain are Banana bunchy top virus (BBTV), a complex of banana streak viruses (BSVs) and Banana bract mosaic virus (BBrMV). BBTV is known to cause the most serious economic losses in the "Old World," contributing to a yield reduction of up to 100% and responsible for a dramatic reduction in cropping area. The BSVs exist as episomal and endogenous forms are known to be worldwide in distribution. In India and the Philippines, BBrMV is known to be economically important but recently the virus was discovered in Colombia and Costa Rica, thus signaling its spread into the "New World." Banana and plantain are also known to be susceptible to five other viruses of minor significance, such as Abaca mosaic virus, Abaca bunchy top virus, Banana mild mosaic virus, Banana virus X, and Cucumber mosaic virus. Studies over the past 100 years have contributed to important knowledge on disease biology, distribution, and spread. Research during the last 25 years have led to a better understanding of the virus-vector-host interactions, virus diversity, disease etiology, and epidemiology. In addition, new diagnostic tools were developed which were used for surveillance and the certification of planting material. Due to a lack of durable host resistance in the Musa spp., phytosanitary measures and the use of virus-free planting material are the major methods of virus control. The state of knowledge on BBTV, BBrMV, and BSVs, and other minor viruses, disease spread, and control are summarized in this review.


Assuntos
Musa/virologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia , Vírus de Plantas/crescimento & desenvolvimento , Plantago/virologia , Resistência à Doença , Vida Livre de Germes , Controle de Insetos/métodos , Musa/imunologia , Musa/parasitologia , Plantago/imunologia , Plantago/parasitologia , Clima Tropical
16.
Infect Genet Evol ; 30: 230-237, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25535945

RESUMO

Cardamom Bushy Dwarf Virus (CBDV) is an aphid-borne nanovirus which infects large cardamom, Amomum subulatum (Zingiberaceae family), in the Himalayan foothills of Northeast India, Nepal and Bhutan. Two aphid species have been reported to transmit CBDV, including Pentalonia nigronervosa and Micromyzus kalimpongensis (also described as Pentalonia kalimpongensis). However, P. nigronervosa was recently split into two species which exhibit different host plant affiliations. Whilst P. nigronervosa primarily feeds on banana plants, Pentaloniacaladii (previously considered a 'form' of P. nigronervosa) typically feeds on plants belonging to the Araceae, Heliconiaceae and Zingiberaceae families. This raises the possibility that CBDV vectors that were originally described as P. nigronervosa correspond to P. caladii. Accurate identification of vector species is important for understanding disease dynamics and for implementing management strategies. However, closely related species can be difficult to distinguish based on morphological characteristics. In this study, we used molecular markers (two mitochondrial loci and one nuclear locus) and Bayesian phylogenetic analyses to identify aphid specimens collected from 148 CBDV infected plants at a range of locations and elevations throughout Sikkim and the Darjeeling district of West Bengal (Northeast India). Our results revealed the presence of a diversity of lineages, comprising up to six distinct species in at least two related genera. These included the three species mentioned above, an unidentified Pentalonia species and two lineages belonging to an unknown genus. Surprisingly, P. caladii was only detected on a single infected plant, indicating that this species may not play an important role in CBDV transmission dynamics. Distinct elevation distributions were observed for the different species, demonstrating that the community composition of aphids which feed on large cardamom plants changes across an elevation gradient. This has implications for understanding how competent vector species could influence spatial and temporal transmission patterns of CBDV.


Assuntos
Afídeos/genética , Babuvirus , Ecossistema , Insetos Vetores/genética , Animais , Afídeos/classificação , Afídeos/virologia , Elettaria/parasitologia , Elettaria/virologia , Índia , Insetos Vetores/classificação , Insetos Vetores/virologia , Musa/parasitologia , Musa/virologia , Filogenia , Doenças das Plantas/parasitologia , Doenças das Plantas/virologia
17.
Indian J Exp Biol ; 52(3): 252-60, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24669668

RESUMO

Activity differences of the first (phenylalanine ammonia lyase, PAL) and the last (cinnamyl alcohol dehydrogenase, CAD) enzymes of phenylpropanoid pathway in the roots of resistant (Yangambi Km5 and Anaikomban) and susceptible (Nendran and Robusta) banana cultivars caused by root lesion nematode, Pratylenchus coffeae, were investigated. Also, the accumulation of phenolics and deposition of lignin polymers in cell walls in relation to resistance of the banana cultivars to the nematode were analyzed. Compared to the susceptible cultivars, the resistant cultivars had constitutively significantly higher PAL activity and total soluble and cell wall-bound phenolics than in susceptible cultivars. The resistant cultivars responded strongly to the infection of the nematode by induction of several-time higher PAL and CAD enzymes activities, soluble and wall-bound phenolics and enrichment of lignin polymers in cell wall and these biochemical parameters reached maximum at 7th day postinoculation. In addition, profiles of phenolic acid metabolites in roots of Yangambi Km5 and Nendran were analyzed by HPLC to ascertain the underlying biochemical mechanism of bananas resistance to the nematode. Identification and quantification of soluble and cell wall-bound phenolic acids showed six metabolites and only quantitative, no qualitative, differences occurred between the resistant and susceptible cvs. and between constitutive and induced contents. A very prominent increase of p-coumaric, ferulic and sinapic acids, which are precursors of monolignols of lignin, in resistant cv. was found. These constitutive and induced biochemical alterations are definitely the chemical defenses of resistant cvs. to the nematode infection.


Assuntos
Resistência à Doença/genética , Fenóis/metabolismo , Doenças das Plantas/genética , Propanóis/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Animais , Redes e Vias Metabólicas , Musa/enzimologia , Musa/genética , Musa/crescimento & desenvolvimento , Musa/parasitologia , Nematoides/genética , Nematoides/patogenicidade , Fenóis/química , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Doenças das Plantas/parasitologia , Raízes de Plantas/enzimologia , Raízes de Plantas/metabolismo , Polímeros/química , Propanóis/química
18.
Proc Natl Acad Sci U S A ; 111(1): 105-10, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24324151

RESUMO

The global yield of bananas-one of the most important food crops-is severely hampered by parasites, such as nematodes, which cause yield losses up to 75%. Plant-nematode interactions of two banana cultivars differing in susceptibility to Radopholus similis were investigated by combining the conventional and spatially resolved analytical techniques (1)H NMR spectroscopy, matrix-free UV-laser desorption/ionization mass spectrometric imaging, and Raman microspectroscopy. This innovative combination of analytical techniques was applied to isolate, identify, and locate the banana-specific type of phytoalexins, phenylphenalenones, in the R. similis-caused lesions of the plants. The striking antinematode activity of the phenylphenalenone anigorufone, its ingestion by the nematode, and its subsequent localization in lipid droplets within the nematode is reported. The importance of varying local concentrations of these specialized metabolites in infected plant tissues, their involvement in the plant's defense system, and derived strategies for improving banana resistance are highlighted.


Assuntos
Resistência à Doença , Musa/metabolismo , Musa/parasitologia , Fenóis/química , Doenças das Plantas/parasitologia , Sesquiterpenos/química , Tylenchoidea , Animais , Interações Hospedeiro-Parasita , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Raízes de Plantas/parasitologia , Análise Espectral Raman , Raios Ultravioleta , Fitoalexinas
19.
Biomed Res Int ; 2013: 184756, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24187659

RESUMO

The objective of this study was to select strains of Beauveria bassiana for controlling Cosmopolites sordidus (Germ.) in plantain farms (cv. Terra) of the "Recôncavo" and southern regions in the state of Bahia, Brazil. The virulence of 32 B. bassiana isolates against C. sordidus was determined under laboratory conditions. Three isolates (CNPMF 407, CNPMF 218, and CNPMF 416) were selected for evaluation under field conditions in plantations located in the counties of Mutuípe and Wenceslau Guimarães. Population of C. sordidus was estimated every 15 days by using pseudostem traps. The efficiency of the three strains of B. bassiana was compared to chemical control (carbofuran, 4 g/trap) and absence of control. Carbofuran caused around 90% of adult mortality after 12 months, with a reduction in the population of C. sordidus since the first evaluation. A low number of trapped insects was observed in the fungus-treated plots, suggesting the efficiency of the isolates in controlling the C. sordidus population. The strain CNPMF 218 was the most efficient in controlling C. sordidus adults in both locations, causing around 20% mortality, leading to 40% population size reduction after 12 months.


Assuntos
Beauveria/fisiologia , Besouros/microbiologia , Musa/parasitologia , Controle Biológico de Vetores , Envelhecimento , Animais , Beauveria/isolamento & purificação , Besouros/crescimento & desenvolvimento , Dinâmica Populacional
20.
Neotrop Entomol ; 42(1): 115-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23949721

RESUMO

Elixothrips brevisetis (Bagnall), a species exotic to Brazil, is first recorded in the country. Individuals were collected on banana fruits (Musa sp.) (Musaceae) in July 2010 in the municipality of Luís Alves, state of Santa Catarina, causing rusting on the fruit peel in several bunches of bananas.


Assuntos
Frutas/parasitologia , Musa/parasitologia , Tisanópteros/fisiologia , Animais , Brasil , Tisanópteros/anatomia & histologia
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