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1.
Pestic Biochem Physiol ; 167: 104601, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32527429

RESUMO

Dinotefuran, the third-generation neonicotinoid, has been applied against melon/cotton aphid Aphis gossypii Glover in China. The risk of resistance development, cross-resistance pattern and potential resistance mechanism of dinotefuran in A. gossypii were investigated. A dinotefuran-resistant strain of A. gossypii (DinR) with 74.7-fold resistance was established by continuous selection using dinotefuran. The DinR strain showed a medium level of cross resistance to thiamethoxam (15.2-fold), but no cross resistance to imidacloprid. The synergism assay indicated that piperonyl butoxide and triphenyl phosphate showed synergistic effects on dinotefuran toxicity to the DinR strain with a synergistic ratio of 8.3 and 2.5, respectively, while diethyl maleate showed no synergistic effect. The activities of cytochrome P450 monooxygenase and carboxylesterase were significantly higher in DinR strain than in susceptible strain (SS). Moreover, the gene expression results showed that CYP6CY14, CYP6CY22 and CYP6UN1 were significantly overexpressed in DinR strain compared with SS strain. The expression of CYP6CY14 was 5.8-fold higher in DinR strain than in SS strain. Additionally, the transcription of CYP6CY14, CYP6CY22 and CYP6UN1 in A. gossypii showed dose- and time-dependent responses to dinotefuran exposure. Furthermore, knockdown of CYP6CY14, CYP6CY22 and CYP6UN1 via RNA interference (RNAi) significantly increased mortality of A. gossypii, when A. gossypii was treated with dinotefuran. These results demonstrated the overexpression of CYP6CY14, CYP6CY22 and CYP6UN1 contributed to dinotefuran resistance in A. gossypii.


Assuntos
Afídeos , Cucurbitaceae , Inseticidas , Animais , China , Sistema Enzimático do Citocromo P-450 , Guanidinas , Resistência a Inseticidas , Neonicotinoides , Nitrocompostos
2.
Zhongguo Zhong Yao Za Zhi ; 45(5): 1076-1081, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32237449

RESUMO

To prepare the herpetolide A nanosuspension lyophilized powder(HPA-NS-LP), in order to investigate its anti-hepatitis B virus(HBV) activity and the dissolution in vitro. Herpetolide A nanosuspension(HPA-NS) was prepared by ultrasonic precipitation method. The formulation and process of HPA-NS were optimized by the single factor experiment. Lyophilized powder(HPA-NS-LP) was prepared by freeze-drying method. Scanning electron microscopy was used to observe morphology of HPA-NS-LP. Paddle method was used to determinate the dissolution of HPT-NS-LP in vitro. The anti-HBV activity of herpetolide A coarse suspension lyophilized powder(HPA-CS-LP) and HPA-NS-LP was evaluated by HepG2.2.15 cell model. The mean particle size of optimized HPA-NS was(173.46±4.36) nm, with a polydispersity index of 0.110±0.012. After redispersion, the mean particle size and the polydispersity index of HPA-NS-LP increased, with changes within a rational range. Scanning electron microscopy showed that HPA-NS-LP was spherical in shape. Cumulative dissolution rate of HPA-NS-LP was more than 90% in 2 hours, which was higher than that of HPA-CS-LP. Both HPA-CS-LP and HPA-NS-LP could effectively inhibit the secretion of HepG2.2.15 cell antigens(HBsAg and HBeAg), and the inhibitory effect of HPA-NS-LP was significantly higher than that of HPA CS-LP(P<0.05). HBV-DNA test showed that high, medium and low-dose HPA-NS-LP(50, 25, 12.5 mg·kg~(-1)) significantly decreased the level of HBV-DNA(P<0.05), and the effect was better than that of the same dose of HPA-CS-LP(P<0.05). The results revealed that HPA-NS-LP exhibited anti-HBV activity in vitro, and its effect was superior to that of HPA-CS-LP.


Assuntos
Cumarínicos/farmacologia , Cucurbitaceae/química , Vírus da Hepatite B/efeitos dos fármacos , Nanopartículas , Compostos Fitoquímicos/farmacologia , Cumarínicos/isolamento & purificação , Células Hep G2 , Humanos , Tamanho da Partícula , Compostos Fitoquímicos/isolamento & purificação , Solubilidade , Suspensões
3.
Phytopathology ; 110(9): 1578-1587, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32314948

RESUMO

Pseudoperonospora cubensis, the causal agent of cucurbit downy mildew, is an airborne, obligate oomycete pathogen that re-emerged in 2004 and causes foliar disease and yield losses in all major cucurbit crops in the United States. Approximately 60 species in the family Cucurbitaceae have been reported as hosts of P. cubensis. Commercial hosts including cucumber, cantaloupe, pumpkin, squash, and watermelon are grown in North Carolina and many host species occur in the wild as weeds. Little is known about the contribution of wild cucurbits to the yearly epidemic; thus, this study aimed to determine the role of commercial and wild cucurbits in the structuring of P. cubensis populations in North Carolina, a region with high pathogen diversity. Ten microsatellite markers were used to analyze 385 isolates from six commercial and four wild cucurbits from three locations representing different growing regions across North Carolina. Population analyses revealed that wild and commercial cucurbits are hosts of P. cubensis in the United States, that host is the main factor structuring P. cubensis populations, and that P. cubensis has two distinct, host-adapted clades at the cucurbit species level, with clade 1 showing random mating and evidence of recombination and clade 2 showing nonrandom mating and no evidence of recombination. Our findings have implications for disease management because clade-specific factors such as host susceptibility and inoculum availability of each clade by region may influence P. cubensis outbreaks in different commercial cucurbits, timing of fungicide applications, and phenotyping for breeding efforts.


Assuntos
Cucurbitaceae , Oomicetos , North Carolina , Peronospora , Doenças das Plantas
4.
Environ Sci Pollut Res Int ; 27(17): 21892-21904, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32285384

RESUMO

Coccinia grandis (C. grandis) L is an Indian medicinal plant from the Cucurbitaceae family whose extracts possess anti-oxidant, anti-infective, and anti-inflammatory properties. The objective of the present study was to probe the potential immunomodulatory of C. grandis crude extract on different pathways in THP-1 cells as probed by changes in expression of several proteins. THP-1 cells were differentiated into macrophages after treatment with phorbol-12-myristate 13-acetate, followed by exposure to lipopolysaccharide (LPS) with or without 50 or 100 µg/ml of C. grandis extract. Treatment of the cells with the extract significantly downregulated the expression and release of pro-inflammatory cytokines (IL-6, IL-1ß, CCL2, CCL22, CXCL10/IP-10, CX3CL1 and CXCL8/IL-8), proteins (ERK5, BAX, BCL2, Cyclin D, ERK1, NF-κB, P-IκBα,P- NF-κB and P-p38) and molecular signaling pathways (NF-κB, p38 MAPK, ERK1/2 and IL-6/JAK/STAT3 signaling cascades). This study is the first to highlight the ability of C. grandis extract to modulate several pathways, including proliferation, the expression of inflammatory cytokines, phagocytosis, migration properties and apoptosis, in human monocytic THP-1 cells.


Assuntos
Cucurbitaceae , Lipopolissacarídeos , Anti-Inflamatórios , Citocinas , Humanos , NF-kappa B , Extratos Vegetais , Células THP-1
5.
Nat Commun ; 11(1): 1859, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313019

RESUMO

Bacteria can form biofilms that consist of multicellular communities embedded in an extracellular matrix (ECM). In Bacillus subtilis, the main protein component of the ECM is the functional amyloid TasA. Here, we study further the roles played by TasA in B. subtilis physiology and biofilm formation on plant leaves and in vitro. We show that ΔtasA cells exhibit a range of cytological symptoms indicative of excessive cellular stress leading to increased cell death. TasA associates to the detergent-resistant fraction of the cell membrane, and the distribution of the flotillin-like protein FloT is altered in ΔtasA cells. We propose that, in addition to a structural function during ECM assembly and interactions with plants, TasA contributes to the stabilization of membrane dynamics as cells enter stationary phase.


Assuntos
Proteínas Amiloidogênicas/metabolismo , Bacillus/fisiologia , Proteínas de Bactérias/metabolismo , Proteínas Amiloidogênicas/genética , Bacillus subtilis/metabolismo , Aderência Bacteriana , Proteínas de Bactérias/genética , Biofilmes , Morte Celular , Membrana Celular/metabolismo , Cucurbitaceae/microbiologia , Ecologia , Lipopeptídeos , Mutação , Transcriptoma
6.
PLoS One ; 15(4): e0220097, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310943

RESUMO

Pulsed light, as a postharvest technology, is an alternative to traditional fungicides, and can be used on a wide variety of fruit and vegetables for sanitization or pathogen control. In addition to these applications, other effects also are detected in vegetal cells, including changes in metabolism and secondary metabolite production, which directly affect disease control response mechanisms. This study aimed to evaluate pulsed ultraviolet light in controlling postharvest rot, caused by Fusarium pallidoroseum in 'Spanish' melon, in natura, and its implications in disease control as a function of metabolomic variation to fungicidal or fungistatic effects. The dose of pulsed light (PL) that inhibited F. pallidoroseum growth in melons (Cucumis melo var. Spanish) was 9 KJ m-2. Ultra-performance liquid chromatography (UPLC) coupled to a quadrupole-time-of-flight (QTOF) mass analyzer identified 12 compounds based on tandem mass spectrometry (MS/MS) fragmentation patterns. Chemometric analysis by Principal Components Analysis (PCA) and Orthogonal Partial Least Squared Discriminant Analysis (OPLS-DA) and corresponding S-Plot were used to evaluate the changes in fruit metabolism. PL technology provided protection against postharvest disease in melons, directly inhibiting the growth of F. pallidoroseum through the upregulation of specific fruit biomarkers such as pipecolic acid (11), saponarin (7), and orientin (3), which acted as major markers for the defense system against pathogens. PL can thus be proposed as a postharvest technology to prevent chemical fungicides and may be applied to reduce the decay of melon quality during its export and storage.


Assuntos
Cucurbitaceae/microbiologia , Cucurbitaceae/efeitos da radiação , Fusarium/efeitos da radiação , Doenças das Plantas/microbiologia , Doenças das Plantas/terapia , Apigenina/metabolismo , Cucurbitaceae/metabolismo , Flavonoides/metabolismo , Fusarium/crescimento & desenvolvimento , Glucosídeos/metabolismo , Metabolômica/métodos , Ácidos Pipecólicos/metabolismo , Raios Ultravioleta
7.
Exp Parasitol ; 212: 107873, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32165146

RESUMO

Ginsenoside-Rh2 and cucurbitacin-B (CuB) are secondary metabolites of Ginseng (Panax ginseng) and Cucurbitaceae plants respectively. We assessed the anticryptosporidial activity of these two functional compounds in a cell culture model of cryptosporidiosis. The highest concentration of each compound that was not toxic to the host cells was used to assess the activity against C. parvum during infection/invasion and growth in HCT-8 cell monolayers. Monolayers were infected with pre-excysted C. parvum oocysts. Infected monolayers were incubated at 37 °C for 24 h and 48 h in the presence of different concentrations of each test compound. A growth resumption assay was performed by incubating infected monolayers in the presence of compounds for 24 h followed by a second 24-h incubation in the absence of compound. To screen for invasion inhibiting activity, freshly excysted C. parvum sporozoites were pre-treated with different concentrations of compounds prior to adding them to the cell monolayers. Paromomycin, a known inhibitor of C. parvum, and DMSO were used as positive and negative control, respectively. The level of infection was initially assessed using an immunofluorescent assay and quantified by real-time PCR. Both compounds were found to strongly inhibit C. parvum intracellular development in a dose-dependent manner. IC50 values of 25 µM for a 24 h development period and 5.52 µM after 48 h development were measured for Rh2, whereas for CuB an IC50 value of 0.169 µg/ml and 0.118 µg/ml were obtained for the same incubation periods. CuB also effectively inhibited resumption of growth, an activity that was not observed with Rh2. CuB was more effective at inhibiting excystation and/or host cell invasion, indicating that this compound also targets extracellular stages of the parasite.


Assuntos
Coccidiostáticos/farmacologia , Cryptosporidium parvum/efeitos dos fármacos , Cucurbitacinas/farmacologia , Ginsenosídeos/farmacologia , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Animais , Linhagem Celular , Cryptosporidium parvum/citologia , Cryptosporidium parvum/crescimento & desenvolvimento , Cucurbitaceae/química , Dimetil Sulfóxido , Relação Dose-Resposta a Droga , Concentração Inibidora 50 , Camundongos , Panax/química , Paromomicina/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Solventes
8.
Plant Dis ; 104(5): 1465-1476, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32191160

RESUMO

Fusarium solani f. sp. cucurbitae (syn. Neocosmosporum cucurbitae) is one of the most devastating soilborne pathogens affecting the production of cucurbits worldwide. Since its first detection in Almería Province in Spain in the spring of 2007, it has become one of the main soilborne pathogens affecting zucchini production. It has also been reported on melon, watermelon, and squash rootstocks in Spain, representing a high risk of dissemination in the area. The objectives of this study were to investigate the incidence and distribution of this disease in southeastern Spain and characterize isolates collected over 5 years. These strains were characterized on the basis of greenhouse aggressiveness assays on a range of cucurbit hosts, morphological characteristics, and elongation factor 1-α and RNA polymerase II second largest subunit phylogenies. All pathogenic isolates were highly aggressive on zucchini plants, causing a high mortality rate a few weeks after inoculation. The rest of the cucurbit hosts showed differential susceptibility to the pathogen, with cucumber being the least susceptible. Plants belonging to other families remained asymptomatic. Morphological characterization revealed the formation of verticilate monophialides and chlamydospores forming long chains, characteristics not described for this forma specialis. Phylogenetic studies of both the individual loci and combined datasets revealed that all pathogenic isolates clustered together with strong monophyletic support, nested within clade 3 in the F. solani species complex.


Assuntos
Citrullus , Cucurbitaceae , Fusarium , Filogenia , Espanha
9.
J Dairy Sci ; 103(4): 3038-3044, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32037169

RESUMO

Nisin, a natural peptide produced by Lactococcus lactis cultivation in milk whey, is widely used as a preservative in industrial production. However, nisin can be degraded by endogenous enzymes in foods. In this study, we investigated the antibacterial activity of nisin-soybean protein and nisin-egg white protein and compared them with that of free nisin in cantaloupe juice, which was used as a model of endogenous protease environment. Results showed that endogenous proteases in the model resulted in a loss of nisin activity, but combining nisin with protein (soybean or egg white) resulted in greater protection of its antimicrobial activity by inhibiting endogenous proteases. The microbial addition experiment (Staphylococcus aureus and Micrococcus luteus) and preservation experiment in the food model showed that the antibacterial activity of nisin combined with either of the 2 proteins was higher than that of nisin alone in an endogenous protease environment. In summary, soybean protein and egg white protein improved the protease tolerance of nisin, expanding the application scope of nisin in food.


Assuntos
Antibacterianos/farmacologia , Nisina/farmacologia , Peptídeo Hidrolases/metabolismo , Proteínas de Soja/farmacologia , Animais , Cucurbitaceae , Endopeptidases/metabolismo , Microbiologia de Alimentos , Lactococcus lactis/metabolismo , Leite/metabolismo , Peptídeo Hidrolases/farmacologia , Inibidores de Proteases/farmacologia , Staphylococcus aureus/metabolismo , Proteínas do Soro do Leite/metabolismo
10.
J Dairy Sci ; 103(4): 2956-2968, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32089310

RESUMO

We developed a synbiotic yogurt using monk fruit extract as a sweetener and investigated the effects of feeding the yogurt to rats with type 2 diabetes induced by streptozotocin and a high-fat diet. The rats fed the synbiotic yogurt showed greater blood glucose regulation and a significant decrease in insulin resistance and glycosylated hemoglobin compared with rats fed yogurt sweetened with sucrose, and they showed a remarkable improvement in short-chain fatty acid levels and gut microbiota status. Liver and kidney damage was also ameliorated in the rats fed the synbiotic yogurt. Immunohistochemistry analysis showed that the synbiotic yogurt inhibited ß-cell loss compared with the control yogurt. Consuming the synbiotic yogurt helped to restore the islets of Langerhans. Our results indicated that monk fruit extract may be a good alternative to sucrose for synbiotic yogurt products in people with type 2 diabetes to delay the progression of diabetes and associated complications.


Assuntos
Cucurbitaceae/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Edulcorantes/farmacologia , Iogurte , Animais , Dieta Hiperlipídica , Frutas/química , Resistência à Insulina , Fígado/patologia , Masculino , Ratos , Ratos Wistar , Simbióticos , Iogurte/análise
11.
PLoS One ; 15(2): e0227284, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32050262

RESUMO

Phytophthora blight caused by Phytophthora capsici is a devastating disease for melon plant. However, the underlying resistance mechanisms are still poorly understood. In this study, the transcriptome differences between the resistant ZQK9 and susceptible E31 at 0, 3, and 5 days post-inoculation (dpi) were identified by RNA-seq. A total of 1,195 and 6,595 differentially expressed genes (DEGs) were identified in ZQK9 and E31, respectively. P. capsici infection triggered massive transcript changes in the inoculated tissues. Genes related to plant defense responses were activated, which was reflected by a lot of up-regulated DEGs involved in pathogenesis-related (PR) genes, hormones biosynthesis and signal transduction, secondary metabolites biosynthesis and cell wall modification in resistant ZQK9. The dataset generated in this study may provide a basis for identifying candidate resistant genes in melon against P. capsici and lay a foundation for further research on the molecular mechanisms.


Assuntos
Cucurbitaceae/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Transcriptoma/genética , Perfilação da Expressão Gênica/métodos , Phytophthora/crescimento & desenvolvimento
12.
Food Chem ; 316: 126342, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32044706

RESUMO

The types and amounts of volatiles in the fruits of 39 melon cultivars were determined. We identified 146 volatiles, including 55 esters, 23 aldehydes, 30 alcohols, 15 ketones, 6 acids and 17 others. Ethyl acetate, (Z)-6-nonenal and 3,6-(E,Z)-nonadien-1-ol were the most three abundant volatiles (average content > 50 µg/kg FW). Aroma profiles showed significant differences among cultivars. Zhongtian49 and Zhongtian20 had the most abundant aroma components (76) and Jinguniang exhibited the least (23). One non-climacteric inodorus cultivar (Xizhoumi25) had the highest content of total volatiles (1840 µg/kg FW). Principal component analysis clustered the 39 melon cultivars into five groups. This work describes the comparative diversity of melon fruit volatiles for a large number of cultivars. Furthermore, this study could support the selection of cultivars with a flavor that suits the public and also future breeding work towards the genetic improvement of melon flavor.


Assuntos
Cucurbitaceae/química , Compostos Orgânicos Voláteis/análise , Álcoois/análise , Aldeídos/análise , Ésteres/análise , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cetonas/análise , Odorantes/análise , Microextração em Fase Sólida/métodos
13.
Gene ; 735: 144403, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32004668

RESUMO

Melon (Cucumis melo L.), an economically beneficial crop widely cultivated around the world, is vulnerable to powdery mildew (PM). However, the studies on molecular mechanism of melon response to PM fungi is still limited. Long non coding RNAs (lncRNAs) have emerged as new regulators in plants response to biotic stresses. We predicted and identified the intricate regulatory roles of lncRNAs in melon response to PM fungi. A total of 539 lncRNAs were identified from PM-resistant (MR-1) and susceptible melon (Top Mark), in which 254 were significantly altered after PM fungi infection. Multiple target genes of lncRNAs were found to be involved in the hydrolysis of chitin, callose deposition and cell wall thickening, plant-pathogen interaction and plant hormone signal transduction pathway. Additionally, a total of 42 lncRNAs possess the various functions with microRNAs (miRNAs), including lncRNAs that are targeted by miRNAs and function as miRNA precursors or miRNA sponges. These findings provide a comprehensive view of potentially functional lncRNAs, corresponding target genes and related lncRNA-miRNA pairs, which will greatly increase our knowledge of the mechanism underlying susceptibility and resistance to PM in melon.


Assuntos
Ascomicetos/patogenicidade , Cucurbitaceae/genética , Resistência à Doença , Redes Reguladoras de Genes , RNA Longo não Codificante/genética , Quitina/metabolismo , Cucurbitaceae/microbiologia , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Transcriptoma
14.
Phytopathology ; 110(5): 989-998, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31971868

RESUMO

Plant pathogenic bacteria in the genus Erwinia cause economically important diseases, including bacterial wilt of cucurbits caused by Erwinia tracheiphila. Conventional bactericides are insufficient to control this disease. Using high-throughput screening, 464 small molecules (SMs) with either cidal or static activity at 100 µM against a cucumber strain of E. tracheiphila were identified. Among them, 20 SMs (SM1 to SM20), composed of nine distinct chemical moiety structures, were cidal to multiple E. tracheiphila strains at 100 µM. These lead SMs had low toxicity to human cells and honey bees at 100 µM. No phytotoxicity was observed on melon plants at 100 µM, except when SM12 was either mixed with Silwet L-77 and foliar sprayed or when delivered through the roots. Lead SMs did not inhibit the growth of beneficial Pseudomonas and Enterobacter species but inhibited the growth of Bacillus species. Nineteen SMs were cidal to Xanthomonas cucurbitae and showed >50% growth inhibition against Pseudomonas syringae pv. lachrymans. In addition, 19 SMs were cidal or static against Erwinia amylovora in vitro. Five SMs demonstrated potential to suppress E. tracheiphila when foliar sprayed on melon plants at 2× the minimum bactericidal concentration. Thirteen SMs reduced Et load in melon plants when delivered via roots. Temperature and light did not affect the activity of SMs. In vitro cidal activity was observed after 3 to 10 h of exposure to these five SMs. Here, we report 19 SMs that provide chemical scaffolds for future development of bactericides against plant pathogenic bacterial species.


Assuntos
Cucurbitaceae , Erwinia , Animais , Peso Molecular , Doenças das Plantas
15.
J Chem Ecol ; 46(3): 275-287, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31989491

RESUMO

Herbivorous insects employ host plant volatile blends as cue for host recognition. Adults of Aulacophora foveicollis Lucas (Coleoptera: Chrysomelidae) feed on leaves, flowers, and fruits of Solena amplexicaulis (Lam.) Gandhi (syn: Melothria heterophylla) (Cucurbitaceae), commonly known as creeping cucumber. Currently, this pest is controlled by insecticides application. Hence, it is necessary to find out volatile components from fruits attracting the insect, which might be used for eco-friendly pest management program. behavioral responses of females were measured by Y-tube olfactometer bioassays towards volatile blends from undamaged (UD), insect-damaged (ID), and mechanically damaged (MD) fruits with the aim to identify the compounds responsible for host fruit location. Volatile organic compounds were identified and quantified by GC-MS and GC-FID analyses, respectively. Nonanal was predominant in volatile blends of UD, ID, and MD fruits. 1-Octen-3-ol, 3-octanone, 2-octanol, heptadienal (2E,4E), 1-pentadecanol, and 1-hexadecanol were present in volatile blends of ID and MD fruits, but females did not show response to these six compounds. 1-Octanol and 1-heptadecanol were unique in volatile blends of UD fruits after 4 hr of damage, but females did not show response to these compounds. Females were more attracted to volatile blends from UD fruits after 4 hr of damage in comparison to volatile blends released by UD fruits, due to increased emissions of (E,Z)-2,6-nonadienal and 2E-nonenal. A synthetic blend of 3.35 µg (E,Z)-2,6-nonadienal and 1.72 µg 2E-nonenal dissolved in 25 µl CH2Cl2 could be used for the development of baited traps to control this insect pest in integrated pest management strategies.


Assuntos
Besouros/fisiologia , Cucurbitaceae/química , Herbivoria , Compostos Orgânicos Voláteis/metabolismo , Animais , Quimiotaxia , Feminino , Cadeia Alimentar , Frutas/química , Masculino
16.
J Asian Nat Prod Res ; 22(1): 30-37, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31328543

RESUMO

The rhizomes of the medicinal plant Hemsleya amabilis (Cucurbitaceae) yielded three new cucurbitane-type triterpene saponins xuedanosides K-M (1-3) by silica gel column, ODS column, and pre-HPLC techniques. The structure was determined by spectroscopic analysis and examined alongside existing data from prior studies. Compounds 1-3 were evaluated for cytotoxic activity against HeLa and HCT-8 human cancer cell lines and showed significant cytotoxicity with IC50 values of 2.01-14.56 and 8.94-27.48 µM, respectively.


Assuntos
Cucurbitaceae , Saponinas , Triterpenos , Glicosídeos , Humanos , Estrutura Molecular
17.
Ecotoxicology ; 29(1): 97-107, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31832831

RESUMO

The extensive use of insecticides can cause adverse side effects on pollinators, which negatively impact crop productivity. The pollination carried out by the honeybee Apis mellifera L. (Hymenoptera: Apidae) is crucial in increasing the productivity of the melon (Cucumis melo L.). The main objective of this study was to assess if insecticides applied in the cultivation of cantaloupe melon exhibit significant levels of toxicity toward A. mellifera. We tested the toxicity of azadirachtin, pyriproxyfen, chlorantraniliprole, and imidacloprid, which are commonly sprayed to manage melon pests such as the whitefly Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae), the pickleworm Diaphania nitidalis (Stoll) and the melonworm Diaphania hyalinata (L.) (Lepidoptera: Pyralidae). Three treatments were carried out, 0.0×, 0.1x and 1.0x the concentration recommended by the manufacturer for the control of those pests. Repellency tests, analysis of mortality through contact and ingestion, and flight tests were performed. The insecticide imidacloprid caused mortality rates above 90% in all tested exposure pathways, displaying high residue persistence on plants. Although not causing significant mortality in the ingestion test, pyriproxyfen caused significant mortality after exposure through contact, and change in flight ability. Azadirachtin caused mortality in the ingestion test and impaired the flight ability of bees, while chlorantraniliprole only impaired the flight ability. Moreover, bees were not repelled by these insecticides, suggesting that they may collect contaminated food in the field while foraging. Altogether, ecofriendly, alternative pest control options should be developed, as well as the adoption of more selective insecticides, in order to reduce the non-target effects on honeybees and guarantee their pollination services.


Assuntos
Abelhas/fisiologia , Inseticidas/toxicidade , Controle de Pragas/métodos , Animais , Abelhas/efeitos dos fármacos , Brasil , Cucurbitaceae , Voo Animal/efeitos dos fármacos , Lepidópteros , Limoninas , Neonicotinoides , Nitrocompostos , Polinização , Piridinas
18.
Nat Prod Res ; 34(3): 398-404, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30602316

RESUMO

Two new phenolic glycosides, named lanatusosides C (1) and D (2), together with four known compounds (3-6), were isolated from the seeds of Citrullus lanatus. Among them, compounds 3 and 4 were isolated from Cucurbitaceae for the first time, and compound 5 was reported from this plant for the first time. Their structures were elucidated by means of extensive spectral analysis, including HR-ESI-MS, 1H and 13C NMR techniques. The isolated new compounds were evaluated for cytotoxic activity against HepG2 cell line, of which compound 1 demonstrated weak cytotoxicity against the tested cell line.


Assuntos
Citrullus/química , Glicosídeos/isolamento & purificação , Sementes/química , Cucurbitaceae , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/toxicidade , Células Hep G2 , Humanos , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/toxicidade
19.
Plant Dis ; 104(1): 255-259, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31613189

RESUMO

Acidovorax citrulli is the causal agent of bacterial fruit blotch (BFB), a serious threat to cucurbit fruit and seed production worldwide. In recent years, the BFB has spread to many areas of China, mainly via the inadvertent distribution of contaminated commercial seeds. To assess the prevalence of seedborne A. citrulli in commercial watermelon and other cucurbitaceous seedlots in China, a 9-year survey was conducted between 2010 and 2018. A total of 4,839 seedlots of watermelon and other cucurbitaceous species were collected from 13 major seed production areas of China and tested by a semiselective media-based colony PCR technique for A. citrulli. Overall, A. citrulli was detected in 18.00% (871/4,839) of all cucurbitaceous seedlots. The bacterium was detected in 21.59% (38/176), 19.19% (33/172), 23.44% (214/913), 40.76% (247/606), 13.28% (85/640), 15.40% (95/617), 13.25% (73/551), 8.03% (48/598), and 6.71% (38/566) of all commercial seedlots tested from the 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, and 2018 growing seasons, respectively. Additionally, the prevalence of A. citrulli in cucurbit seedlots was determined for different seed production areas. The prevalence of A. citrulli in cucurbitaceous seedlots produced in Xinjiang, Gansu, Ningxia, Inner Mongolia, and 9 other provinces was 18.76% (582/3103), 26.34% (103/391), 21.47% (82/382), 11.11% (14/126), and 10.75% (90/837), respectively. This is the first survey for A. citrulli in commercial cucurbit seeds in China, and the relatively high prevalence suggests that commercial seeds represent a substantial source of primary inoculum that can threaten cucurbit seed and fruit production in China.


Assuntos
Comamonadaceae , Cucurbitaceae , Sementes , China , Comamonadaceae/fisiologia , Cucurbitaceae/microbiologia , Doenças das Plantas/microbiologia , Sementes/microbiologia
20.
Phytopathology ; 110(1): 174-186, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31502517

RESUMO

Mixed viral infections in plants are common, and can result in synergistic or antagonistic interactions. Except in complex diseases with severe symptoms, mixed infections frequently remain unnoticed, and their impact on insect vector transmission is largely unknown. In this study, we considered mixed infections of two unrelated viruses commonly found in melon plants, the crinivirus cucurbit yellow stunting disorder virus (CYSDV) and the potyvirus watermelon mosaic virus (WMV), and evaluated their vector transmission by whiteflies and aphids, respectively. Their dynamics of accumulation was analyzed until 60 days postinoculation (dpi) in mixed-infected plants, documenting reduced titers of WMV and much higher titers of CYSDV compared with single infections. At 24 dpi, corresponding to the peak of CYSDV accumulation, similar whitefly transmission rates were obtained when comparing either individual or mixed-infected plants as CYSDV sources, although its secondary dissemination was slightly biased toward plants previously infected with WMV, regardless of the source plant. However, at later time points, mixed-infected plants partially recovered from the initially severe symptoms, and CYSDV transmission became significantly higher. Interestingly, aphid transmission rates both at early and late time points were unaltered when WMV was acquired from mixed-infected plants despite its reduced accumulation. This lack of correlation between WMV accumulation and transmission could result from compensatory effects observed in the analysis of the aphid feeding behavior by electrical penetration graphs. Thus, our results showed that mixed-infected plants could provide advantages for both viruses, directly favoring CYSDV dissemination while maintaining WMV transmission.


Assuntos
Afídeos , Comportamento Animal , Coinfecção , Cucurbitaceae , Insetos Vetores , Animais , Afídeos/fisiologia , Afídeos/virologia , Cucurbitaceae/virologia , Insetos Vetores/fisiologia , Insetos Vetores/virologia , Doenças das Plantas/virologia
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