Assessment of the Current Status of Potyviruses in Watermelon and Pumpkin Crops in Spain: Epidemiological Impact of Cultivated Plants and Mixed Infections

Viral infections on cucurbit plants cause substantial quality and yield losses on their crops. The diseased plants can often be infected by multiple viruses, and their epidemiology may depend, in addition to the agro-ecological management practices, on the combination of these viral infections. Watermelon mosaic virus (WMV) is one of the most prevalent viruses in cucurbit crops, and Moroccan watermelon mosaic virus (MWMV) emerged as a related species that threatens these crops. The occurrence of WMV and MWMV was monitored in a total of 196 apical-leaf samples of watermelon and pumpkin plants that displayed mosaic symptoms. The samples were collected from 49 fields in three major cucurbit-producing areas in Spain (Castilla La-Mancha, Alicante, and Murcia) for three consecutive (2018–2020) seasons. A molecular hybridization dot-blot method revealed that WMV was mainly (53%) found in both cultivated plants, with an unadvertised occurrence of MWMV. To determine the extent of cultivated plant species and mixed infections on viral dynamics, two infectious cDNA clones were constructed from a WMV isolate (MeWM7), and an MWMV isolate (ZuM10). Based on the full-length genomes, both isolates were grouped phylogenetically with the Emergent and European clades, respectively. Five-cucurbit plant species were infected steadily with either WMV or MWMV cDNA clones, showing variations on symptom expressions. Furthermore, the viral load varied depending on the plant species and infection type. In single infections, the WMV isolate showed a higher viral load than the MWMV isolate in melon and pumpkin, and MWMV only showed higher viral load than the WMV isolate in zucchini plants. However, in mixed infections, the viral load of the WMV isolate was greater than MWMV isolate in melon, watermelon and zucchini, whereas MWMV isolate was markedly reduced in zucchini. These results suggest that the impaired distribution of MWMV in cucurbit crops may be due to the cultivated plant species, in addition to the high prevalence of WMV.

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Novel Cytopathological Structures Induced by Mixed Infection of Unrelated Plant Viruses

Phytopathology ◽

10.1094/phyto.2004.94.1.111 ◽

2004 ◽

Vol 94 (1) ◽

pp. 111-119 ◽

Cited By ~ 11

Author(s):

E. M. Martin ◽

J. D. Cho ◽

J. S. Kim ◽

S. C. Goeke ◽

K. S. Kim ◽

...

Keyword(s):

Mosaic Virus ◽

Mixed Infection ◽

Viral Infections ◽

Soybean Mosaic Virus ◽

Plant Viruses ◽

Mixed Infections ◽

Cowpea Mosaic Virus ◽

Viral Interactions ◽

Sunn Hemp ◽

Blackeye Cowpea Mosaic Virus

When two unrelated plant viruses infect a plant simultaneously, synergistic viral interactions often occur resulting in devastating diseases. This study was initiated to examine ultrastructural virus-virus interactions of mixed viral infections. Mixed infections were induced using potyviruses and viruses from other plant virus families. Novel ultrastructural paracrystalline arrays composed of co-infecting viruses, referred to as mixed virus particle aggregates (MVPAs), were noted in the majority of the mixed infections studied. When the flexuous rod-shaped potyvirus particles involved in MVPAs were sectioned transversely, specific geometrical patterns were noted within some doubly infected cells. Although similar geometrical patterns were associated with MVPAs of various virus combinations, unique characteristics within patterns were consistent in each mixed infection virus pair. Centrally located virus particles within some MVPAs appeared swollen (Southern bean mosaic virus mixed with Blackeye cowpea mosaic virus, Cucumber mosaic virus mixed with Blackeye cowpea mosaic virus, and Sunn hemp mosaic virus mixed with Soybean mosaic virus). This ultrastructural study complements molecular studies of mixed infections of plant viruses by adding the additional dimension of visualizing the interactions between the coinfecting viruses.

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A review of Tuta absoluta (Lepidoptera: Gelechiidae) host plants and their impact on management strategies

BASE - Numéro 3 ◽

10.25518/1780-4507.18211 ◽

2019 ◽

pp. 270-278

Author(s):

Asma Cherif ◽

François Verheggen

Keyword(s):

Plant Species ◽

Host Plants ◽

Insect Pests ◽

Integrated Management ◽

Management Strategies ◽

Scientific Data ◽

Tuta Absoluta ◽

Cultivated Plants ◽

Solanaceae Species ◽

Cultivated Plant

Introduction. Tuta absoluta is one of the most harmful insect pests of tomato crops worldwide. While its host plants mainly include Solanaceae species, recent studies suggest that it can lay eggs and develop on a wider range of wild and cultivated plants. No complete list of host plants based on available scientific data exists. Such information is important for those who aim at performing integrated management strategies against this pest, especially when it comes to identify host reservoirs where the species can survive between harvests or avoid insecticide exposure. Literature. We identified cultivated and non-cultivated plant species belonging to Solanaceae, Amaranthaceae, Euphorbiaceae, Cucurbitaceae, Geraniaceae, Fabaceae, Asteraceae and Malvaceae that allow partial or complete egg-imago development. Among them, we found out that most non-Solanaceous plants serve as oviposition sites only (with no larval development possible), and a few of them allow partial life cycle (causing late instars to die prematurely). We also identified a strong cultivar-dependence in the most common cultivated plant species including tomato and potato. Conclusions. We discuss the potential of resistant and genetically modified tomato cultivars, plant chemical compounds and fertilization as components of integrated control strategies of T. absoluta.

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Frequency and molecular characterization of watermelon mosaic virus from Serbia

Pesticidi i fitomedicina ◽

10.2298/pif1003213v ◽

2010 ◽

Vol 25 (3) ◽

pp. 213-230

Author(s):

Ana Vucurovic ◽

Aleksandra Bulajic ◽

Ivana Stankovic ◽

Danijela Ristic ◽

Janos Berenji ◽

...

Keyword(s):

Virus Infection ◽

Mosaic Virus ◽

Cucurbita Pepo ◽

Zucchini Yellow Mosaic Virus ◽

Growing Season ◽

Yellow Mosaic Virus ◽

Watermelon Mosaic Virus ◽

Mixed Infections ◽

Mediterranean Regions

Watermelon mosaic virus (WMV) is widespread in cucurbit crops, most commonly occuring in temperate and Mediterranean regions. In Serbia WMV has been detected in single and mixed infections with Zucchini yellow mosaic virus and Cucumber mosaic virus in field-grown pumpkin and squash crops. Among pumpkin-affecting viruses WMV is the most frequent one, both by the number of localities and its incidence at each location. During the growing season of 2009, samples from 583 plants of Cucurbita pepo cvs. Olinka, Belgrade zucchini and Tosca (Zucchini group), as well as from C. maxima and C. moschata showing symptoms of virus infection were collected from 12 commercial fields at eight localities and analyzed by DAS-ELI

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The P1 Protein of Watermelon mosaic virus Compromises the Activity as RNA Silencing Suppressor of the P25 Protein of Cucurbit yellow stunting disorder virus

Frontiers in Microbiology ◽

10.3389/fmicb.2021.645530 ◽

2021 ◽

Vol 12 ◽

Author(s):

Maria Luisa Domingo-Calap ◽

Ornela Chase ◽

Mariona Estapé ◽

Ana Beatriz Moreno ◽

Juan José López-Moya

Keyword(s):

Mosaic Virus ◽

Rna Silencing ◽

Viral Infections ◽

Synergistic Effects ◽

Watermelon Mosaic Virus ◽

Additive Effects ◽

Silencing Suppressor ◽

Negative Effect ◽

Helper Component Proteinase ◽

Dose Dependent

Mixed viral infections in plants involving a potyvirus and other unrelated virus often result in synergistic effects, with significant increases in accumulation of the non-potyvirus partner, as in the case of melon plants infected by the potyvirus Watermelon mosaic virus (WMV) and the crinivirus Cucurbit yellow stunting disorder virus (CYSDV). To further explore the synergistic interaction between these two viruses, the activity of RNA silencing suppressors (RSSs) was addressed in transiently co-expressed combinations of heterologous viral products in Nicotiana benthamiana leaves. While the strong RSS activity of WMV Helper Component Proteinase (HCPro) was unaltered, including no evident additive effects observed when co-expressed with the weaker CYSDV P25, an unexpected negative effect of WMV P1 was found on the RSS activity of P25. Analysis of protein expression during the assays showed that the amount of P25 was not reduced when co-expressed with P1. The detrimental action of P1 on the activity of P25 was dose-dependent, and the subcellular localization of fluorescently labeled variants of P1 and P25 when transiently co-expressed showed coincidences both in nucleus and cytoplasm. Also, immunoprecipitation experiments showed interaction of tagged versions of the two proteins. This novel interaction, not previously described in other combinations of potyviruses and criniviruses, might play a role in modulating the complexities of the response to multiple viral infections in susceptible plants.

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Ocorrência de patógenos em cultivos de melancia e abóbora no sertão da Paraíba

Revista Verde de Agroecologia e Desenvolvimento Sustentável ◽

10.18378/rvads.v11i1.3704 ◽

2016 ◽

Vol 11 (1) ◽

pp. 07 ◽

Cited By ~ 2

Author(s):

M. G. F. O. Soares ◽

J. A. Soares ◽

M. A. Cezar ◽

T. A. L. Cardoso ◽

J. A. A. Lima

Keyword(s):

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Zucchini Yellow Mosaic Virus ◽

Morphological Characteristics ◽

Yellow Mosaic Virus ◽

Watermelon Mosaic Virus ◽

Mixed Infections ◽

Spot Virus ◽

Papaya Ring Spot Virus ◽

Ring Spot

Por constituírem uma importante fonte de alimento, plantações de melancia e abóbora são comumente cultivadas no sertão paraibano, porém pouco se sabe sobre a ocorrência de patógenos causadores de doenças, os quais limitam a sua produtividade e renda aos produtores. Visando obter informações sobre a ocorrência dos patógenos virais e fúngicos em cultivos de abóbora e melancia situados em municípios produtores no sertão da Paraíba, amostras coletadas com sintomas de mosaico e deformação foliar, típicos de doenças virais foram analisadas pela técnica sorológica “enzime linked immuno sorbentassay” (Elisa) indireto para Papaya ring spot virus, type watermelon (PRSV-W), Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus (ZYMV) e Cucumber mosaic virus (CMV). O teste de dupla difusão em Agar foi utilizado para verificar a presença de Squash mosaic virus (SqMV). Em contrapartida, amostras coletadas com sintomas de doenças fúngicas foram analisadas pelo isolamento do patógeno e visualização de suas características morfológicas em microscópio óptico. Em abóbora, houve prevalência dos vírus ZYMV e PRSV-W em infecções simples e mistas, e maior incidência dos fungos Cladosporium spp., e Alternaria spp. Em melancia detectou-se infecção simples e mistas das espécies PRSV-W, WMV e ZYMV, e maior freqüência de Fusarium spp. e Alternaria spp.. Não foram detectados os vírus CMV e SqMV. Os resultados obtidos revelam a ocorrência de vários patógenos fúngicos e viróticos em cultivos de abóbora e melancia situados no sertão da Paraíba e ressaltam a importância da utilização de estratégias de manejo que reduzem os danos ocasionados por esses patógenos.Occurrence of pathogens in watermelon and pumpkin crops in the State of ParaibaAbstract: By constitute an important food source, watermelon and pumpkin plantations are commonly grown on Paraíba backlands, but little is known about the occurrence of disease-causing pathogens, which limit their productivity and income to producers. With objective to get information about the viral and fungal pathogens occurrence in pumpkin and watermelon crops in producing counties located in the backlands of Paraiba, samples with symptoms of mosaic and leaf distortion, typical of viral etiology of disease were collected and analyzed by "Enzyme linked immune sorbentassay" (Elisa) Indirect for species Papaya ring spot virus, type watermelon (PRSV-W), Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus ( ZYMV) and Cucumber mosaic virus (CMV). The double diffusion test in Agar was used to verify the presence of Squash mosaic virus (SqMV). In contrast, samples collected with fungal disease symptoms were analyzed based on the isolation of the pathogen and viewing their morphological characteristics under an optical microscope. In pumpkin, there was prevalence of ZYMV and PRSV-W in single and mixed infections, and higher incidence of Cladosporium spp. and Alternaria spp. On the other hand, in watermelon was detected single and mixed infections of PRSV-W, WMV and ZYMV species, and higher frequency of Fusarium spp. and Alternaria spp.. Were not detected the virus CMV and SqMV. The results show the occurrence of various fungal and viral pathogens in pumpkin and watermelon crops located in the backlands of Paraiba and emphasize the importance of using management strategies that reduce the damage caused by these pathogens.

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A Virus-Induced Gene-Silencing Vector Based on a Mild Isolate of Watermelon Mosaic Virus for Reverse Genetic Analyses in Cucurbits

10.21203/rs.3.rs-222617/v1 ◽

2021 ◽

Author(s):

Fakhreddine Houhou ◽

Verónica Aragonés ◽

Anamarija Butković ◽

Cristina Sáez ◽

Belén Picó ◽

...

Keyword(s):

Gene Silencing ◽

Mosaic Virus ◽

Rna Silencing ◽

Viral Infections ◽

Watermelon Mosaic Virus ◽

Reverse Genetic ◽

Virus Induced Gene Silencing ◽

Genetic Analyses ◽

Endogenous Gene ◽

Mild Isolate

Abstract As a response to viral infections, host plants trigger an RNA-mediated gene silencing defense, to which viruses respond with the expression of viral-encoded RNA silencing suppressors. If virus clones are manipulated to include sequences homologous to host endogenous genes, these are also targeted by the plant RNA silencing machinery. This so-called virus-induced gene silencing (VIGS) has become a powerful technique for reverse genetic analyses in plants, as an alternative to labor-intensive genome transformation. We show that a mild isolate of Watermelon mosaic virus (WMV, genus Potyvirus) can be used as a VIGS vector for reverse genetic analyses in melon. Recombinant WMV clones —in which fragments of the melon Phytoene desaturase (PDS) mRNA were inserted in sense, antisense, and hairpin modalities— induced a distinctive phenotype and significant silencing of the endogenous gene. While the foreign fragments in sense and antisense orientations were stable in the viral progeny, the hairpin was quickly lost. Nevertheless, the hairpin construct triggered a maintained silencing effect comparable to those of the sense and antisense constructs. The suitability of WMV as a VIGS vector was further confirmed targeting melon Magnesium chelatase subunit I (CHLI). These results also support that, although potyviruses express a strong silencing suppressor that usually precludes VIGS, mild isolates of this kind of viruses can be used as VIGS vectors. Finally, to facilitate the use of this new tool by cucurbit geneticists, we describe plasmid pGWMV-VIGS that allows easy cloning fragments of the genes of interest in a single Gibson assembly reaction.

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Viruses Associated with Cucurbit Production in Southern Illinois

HortScience ◽

10.21273/hortsci.38.1.65 ◽

2003 ◽

Vol 38 (1) ◽

pp. 65-66 ◽

Cited By ~ 8

Author(s):

S. Alan Walters ◽

Jeffrey D. Kindhart ◽

Houston A. Hobbs ◽

Darin M. Eastburn

Keyword(s):

Mosaic Virus ◽

Zucchini Yellow Mosaic Virus ◽

Viral Disease ◽

Yellow Mosaic Virus ◽

Watermelon Mosaic Virus ◽

Mixed Infections ◽

Papaya Ringspot Virus ◽

Southern Illinois ◽

Growing Seasons ◽

Prevalent Virus

Viruses are a serious threat to cucurbit production in southern Illinois. The most prevalent viruses infecting cucurbit crops in the region were determined during the 1998, 1999, and 2000 growing seasons to enable growers to make better decisions on viral disease management. Watermelon mosaic virus (WMV) was the most prevalent virus as it was found in ≈84% of samples over the three years. Cucumber mosaic virus (CMV), papaya ringspot virus (PRSV), squash mosaic virus (SqMV), and zucchini yellow mosaic virus (ZYMV) were detected in ≈8%, 6%, 9%, and 1% of samples, respectively, over the 3-year period. WMV was generally the only virus isolated from samples collected before mid-September. Other viruses, including CMV, PRSV, SqMV, and ZYMV, were generally first detected after mid-September and were usually found as mixed infections with WMV.

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Assessing the Impact on Virus Transmission and Insect Vector Behavior of a Viral Mixed Infection in Melon

Phytopathology ◽

10.1094/phyto-04-19-0126-fi ◽

2020 ◽

Vol 110 (1) ◽

pp. 174-186 ◽

Cited By ~ 6

Author(s):

Maria Luisa Domingo-Calap ◽

Ana Beatriz Moreno ◽

Juan Antonio Díaz Pendón ◽

Aranzazu Moreno ◽

Alberto Fereres ◽

...

Keyword(s):

Viral Infections ◽

Virus Transmission ◽

Watermelon Mosaic Virus ◽

Mixed Infections ◽

Late Time ◽

Insect Vector ◽

Vector Transmission ◽

Transmission Rates ◽

Time Points ◽

The Impact

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.

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Role of Non-cultivated Flowering Plants in Conservation of Pollinators

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2020/v10i630206 ◽

2020 ◽

pp. 75-81

Author(s):

Zameeroddin . ◽

V. V. Belavadi

Keyword(s):

Plant Species ◽

Flowering Plants ◽

Cultivated Plants ◽

Field Bean ◽

Alternanthera Sessilis ◽

Pollinator Species ◽

Hyptis Suaveolens ◽

Cultivated Plant ◽

Net Method

A study was conducted to emphasize the importance of non-cultivated plants/weeds in North Bangalore, Karnataka from October 2014 to March 2015 in three locations. The pollinators were collected using sweep net method on cultivated and non-cultivated flowering plants. A total of 22 non-cultivated plant species and 11 cultivated plant species were observed on which 85 and 56 pollinator species were collected respectively belonging to the four families (Apidae, Halictidae, Megachilidae and Scoliidae) of Hymenoptera and two families (Syrphidae and Bombyliidae) of Diptera. It is found that association of pollinators were more towards non-cultivated plants than cultivated plants. Among cultivated flowering plants, Ocimum americanum was highly attractive followed by Field bean and Lavandula angustifolia. Among non-cultivated flowering plants, Alternanthera sessilis was highly attractive on which majority were Dipterans followed by Leucas aspera and Hyptis suaveolens indicating the importance of non-cultivated flowering plants/weeds in conservation of pollinators.

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