Quantification and risk assessment of heavy metal build-up in soil-plant system after irrigation with untreated city wastewater in Vehari, Pakistan

In peri-urban areas of district Vehari, farmers are using untreated city wastewater for crop irrigation owing to the scarcity of good-quality irrigation water. This practice may pose severe environmental and health issues to local inhabitants attributed to the high levels of potentially toxic metals in wastewater. The present study evaluated the potential impacts of wastewater irrigation on metals (Cd, Cr, Cu, Fe, Ni, Mn, Pb and Zn) build-up in the soil-plant continuum and associated health risks. In this study, wastewater (n = 17), soil (n = 108) and plant (n = 65) samples were collected from 15 peri-urban sites of three tehsils of district Vehari. Results showed that the mean concentration (mg/L) of Cd (0.02), Mn (0.25) and Fe (1.57) in wastewater samples was higher than their respective threshold values. Similarly, Cd, Mn and Fe concentration in soil was beyond the permissible limits of agricultural soil receiving wastewater irrigation. However, plants showed high accumulation of Pb, Cr and Fe than their respective limits depending on the vegetable/crop species. The health risk parameters showed that Pb and Cd are the major toxic chemical substances to human health, and the daily intake of crop plants can pose a potential health threat due to wastewater-irrigated crop consumption. Results highlighted the necessity of wastewater pretreatment to avoid the soil and vegetable contamination by wastewater irrigation and to reduce the associated health risks.

Additional calcium and sulfur manages hexavalent chromium toxicity in Solanum lycopersicum L. and Solanum melongena L. seedlings by involving nitric oxide

In recent years, nutrient management has gained much attention for mitigating metal stress. But, role of nutrients like calcium (Ca) and sulfur (S) in mitigating Cr(VI) toxicity along with their mechanism of action are still limited. Therefore, the present study was performed to explore role of Ca and S in ameliorating Cr(VI) toxicity in 21 days old seedlings of Solanum lycopersicum L. and Solanum melongena L. Chromium (VI) reduced tolerance index and altered root traits due to greater Cr accumulation in the cell wall and cellular organelles due to down-regulation in thiols and phytochelatins that lead to alterations in photosynthesis. However, Ca or S stimulated vacuolar sequestration of Cr(VI) and reduced its uptake at the cell wall. This was coincided with up-regulation in glutathione-S-transferase activity, and amounts of thiols and phytochelatins. Cr(VI) caused oxidative stress together with up-regulation in superoxide dismutase and catalase, and proline metabolism while Ca and S reversed these effects. Chromium (VI) inhibited nitrate reductase activity while Ca and S reversed this response. NG-nitro-l-arginine methyl ester augmented Cr(VI) toxicity but sodium nitroprusside (SNP) mitigated Cr(VI) toxicity. Overall results show that Ca and S both are able in ameliorating Cr(VI) toxicity and require nitric oxide for this task.

Study of soil to plant transfer factors of 226Ra, 232Th, 40K and 137Cs in Vietnamese crops

The study of staple food products is crucial to assure public safety and provides input for predictive dose assessment models. To further this goal, the activity concentrations, transfer factors, and radiological hazards of ²²⁶Ra, ²³²Th, ⁴⁰K, and ¹³⁷Cs were studied for ten pairs of selected vegetables and soils in Tien Le near Hanoi in Vietnam. This is the first study in this area for Vietnamese vegetable samples. The ten most popular vegetables in Vietnamese diet were selected, namely choy sum, crown daisy, lettuce, cabbage, Malabar spinach, beans, sweet potato, potato, kohlrabi and carrot. The research results showed that the activity concentrations observed in vegetable crops did not present the previously reported strong correlation to those in soil. The ranges of TFs of ²²⁶Ra, ²³²Th, and ⁴⁰K were 4 × 10^-2 - 6.9 × 10^-1, 8 × 10^-2 - 9.7 × 10^-1; and 1.0 × 10⁰-1.6 × 10¹, respectively. Values for leafy vegetables and tubers exceed previous world range figures for Th and K. The soil has been evaluated for radiological hazard indices, which predict almost no risk to human health in the study area.

Dietary intake assessment of pyrethroid residues from okra and eggplant grown in peri-urban areas of Punjab, Pakistan

This study was designed to assess the gradual increase in the use of insecticides on vegetables and to familiarize the consumers regarding the insecticide residues. The purpose of this research work was to highlight the detrimental effects of pyrethroids (bifenthrin, cyfluthrin, cypermethrin, deltamethrin, fenvalerate, lambda-cyhalothrin, and permethrin) compare with dietary intake assessment of eggplant and okra grown in peri-urban environment. In this manner, a total of 180 (n = 60 × 3) samples of eggplant (Solanum melongena) and okra (Abelmoschus esculentus) were procured from the peri-urban farming system of Faisalabad, Multan, and Gujranwala to assess the pyrethroid residues along with their dietary intake assessment. The procured vegetables were quantified for pyrethroid residues by using gas chromatography (GC) equipped with an electron capture detector (ECD). Outcomes of this study revealed that for okra samples, the highest residues of bifenthrin (1.25 mg kg^-1) were found in Gujranwala then Multan (1.5 mg kg^-1) and Faisalabad (1.04 mg kg^-1), whereas in eggplant, the highest residues were recorded for bifenthrin from Faisalabad (1.33 mg kg^-1) and Gujranwala (0.78 mg kg^-1). In Multan, the highest residues for cyfluthrin (1.18 mg kg^-1) were reported in eggplant. Out of all analyzed samples for pyrethroid residues, 32% samples contained detectable residues and 6% samples exceeded their maximum residual limits (MRLs) established by the European Union (EU). Dietary intake assessment (mg kg^-1 day^-1) was calculated as per their maximum permissible intake (MPI) values, i.e., bifenthrin (1.28), cyfluthrin (1.28), cypermethrin (3.20), deltamethrin (0.64), fenvalerate (1.28), lambda-cyhalothrin (0.064), and permethrin (3.20) respectively. Conclusively, residues from the Multan region were greater than those from Gujranwala and Faisalabad showing excessive application of pyrethroids. Overall results revealed that although some samples exceeded MRLs in selected areas, their safe consumption limit was found.

Simple and Green Heat-Induced Deep Eutectic Solvent Microextraction for Determination of Lead and Cadmium in Vegetable Samples by Flame Atomic Absorption Spectrometry: a Multivariate Study

In this study, a simple, green, and cheap analytical procedure based on heat-induced deep eutectic solvent microextraction (HI-DES-ME) coupled with flame atomic absorption spectrometer (FAAS) was developed for the determination of Pb(II) and Cd(II) in vegetables. After the preliminary experiment, response surface methodology (RMS) based on central composite design (CCD) was used for the optimization of critical factors such as pH of sample solution, amount of extraction solvent, temperature, and amount of ligand. Microwave step was applied for the digestion of vegetable samples. Under optimum conditions obtained by the CCD, calibration graphs for Pb(II) and Cd(II) were linear in the concentration range of 0.5-250 and 1.0-300 ng mL^-1, respectively. Limits of detection (LODs) and sensitivity enhancement factor (SIFs) were found in the range of 0.17-0.35 ng mL^-1 and 93-67 ng mL^-1, respectively. Relative standard deviations (N = 10, RSDs%) for Pb(II) (10 ng mL^-1) and Cd(II) (50 ng mL^-1) were 3.7% and 2.3%, respectively. In order to validate the proposed method, certified reference material (CRM) and spiked samples were used. Experimental results showed that there was no significant difference between the obtained and certified values. Then, the proposed method was successfully applied for the preconcentration and determination of Pb(II) and Cd(II) in different vegetables.

The taste of biodiversity: science and sensory education with different varieties of a vegetable to promote acceptance among primary school children

OBJECTIVE

To determine the impact of an educational programme for primary schools that explored the biodiversity of tomato, by promoting science and sensory education with three distinct varieties of it, in the acceptance of vegetables.

DESIGN

A randomised controlled study in which children were exposed to the educational programme (intervention group) or remained in the class, as usual (control group). The educational programme consisted of three sessions where children explained the observed differences between the three varieties of tomato and individual perceptions of their flavours based on sensory-based food education and by planning and implementing experiments to explain those differences. We tested the effects on both children's willingness to try and their liking for tomato, and for lettuce and cabbage to study the carry-over effect, compared with the control group (Mann-Whitney U test; P < 0·05).

SETTING

The study took place in public primary schools in Porto, Portugal.

PARTICIPANTS

Children in the third grade (8-13-year-old children) (n 136) were randomly assigned to intervention or control group.

RESULTS

Children in the intervention group reported significant increases in their willingness to try and liking for tomato compared to the control group (P < 0·05), but not for lettuce and cabbage (P > 0·05).

CONCLUSIONS

These results highlight the potential for fostering children's acceptance of a vegetable by exploring biodiversity through science education. Further work may clarify the effects of exploring biodiversity on the consumption of vegetables and establish whether the results are stable over time and replicable across contexts and populations.

First report of Pectobacterium aroidearum causing bacterial soft rot of carrot in Taiwan

Carrot (Daucus carota) is an important root vegetable planted and consumed worldwide (Stein and Nothnagel 1995). In June 2020, carrots (cv. New Kuroda) showing soft rot symptoms were observed in a 600 sqft plot located in Pitou, Changhua, Taiwan (23°54'00.9"N, 120°28'37.3"E; with around 400 plants). About 10% of the plants on site had similar symptoms; infected taproot tissues were macerated (Figure S1) and emitted a foul odor. In most cases, the peels above the rotten tissues remain intact. Two infected plants were brought to the lab. Macerated tissues were suspended in water and examined under a microscope at 600X (without staining). Rod, motile bacteria were observed in all of the samples and the bacteria were isolated onto nutrient agar. Three bacterial strains were obtained from two taproots; strain Car1 was isolated from one plant, and strains Car2 and Car3 were isolated from the other. Their colonies were translucent, round and convex. All isolates could ferment glucose and induce soft rot symptoms on potato tuber slices (Schaad et al. 2001). They were not able to produce indigoidine on yeast dextrose calcium carbonate agar and were tested negative for phosphatase activity (Schaad et al. 2001). The 16S rDNA of Car1 to Car3 were amplified using primers 27F/1492R (Lane 1991). Cloning and sequencing of their 16S rDNA (GenBank accession no. MT889640) revealed that their sequences shared 99.9% identity (1,463/1,464 bp) with that of Pectobacterium aroidearum CFBP 8168T (SCRI 109T; GenBank accession no. NR_159926.1). Multilocus sequence analyses targeting the three isolates' dnaX, leuS and recA genes were conducted. The concatenated sequences (1,596 bp) of Car1 to Car3 and those included in a previous work (Portier et al. 2019) were subjected to phylogenetic analysis. The sequences of Car1 to Car3 were identical (GenBank accession nos. MT892671-MT892673). A maximum-likelihood tree showed that the three isolates belonged to the same clade as P. aroidearum CFBP 8168T (GenBank accession nos. MK516971, MK517115 and MK517259; Figure S2). For the concatenated sequences analyzed, the identity between P. aroidearum CFBP 8168T and our three isolates was 99.4% (1,587/1,596 bp). The pathogenicity of these isolates was determined by inoculating the bacteria into carrot (cv. Xiangyang No.2) taproots. Strains Car1 to Car3 were grown on NA for 48 h (28 °C) and cell suspensions with OD600 values of 0.3 (2.4 x 108 CFU/ml; in water) were prepared. The suspensions of each strain (100 μl) were loaded into 200 μl pipette tips. The tips were then pierced into intact carrot taproots (2.4 cm deep), ejected and left on the plants (one tip per plant). Three taproots were tested for each strain. Tips loaded with 100 μl of water were used for the controls (three replicates). The plants were incubated in a sealed plastic container kept in a growth chamber set at 28°C. After 48 h, all of the inoculated taproots produced soft rot symptoms resembling those observed in the field and plants in the control group did not. Bacteria were re-isolated from macerated tissues of the artificially infected plants and found to share the same leuS sequence with Car1 to Car3. Occurrences of carrot soft rot in Taiwan have only been attributed to Dickeya spp. (Erwinia chrysanthemi) in previous studies (Hsu and Tzeng 1981). The present study is the first report of P. aroidearum infecting carrots in Taiwan. The findings may add to our understanding of the diversity of soft rot pathogens affecting carrot production in Taiwan.

Isotope chemometrics determines farming methods and geographical origin of vegetables from Yangtze River Delta Region, China

Shanghai city has encountered possible food fraud regarding the geographical mislabeling of vegetables for economic gain. A combination of δ¹³C, δ¹⁵N, δ²H and δ¹⁸O values and partial least squares discrimination analysis and support vector machine (SVM) methods were used for the first time to assess farming methods and determine the origin of vegetables from Shanghai city, Anhui and Zhejiang provinces. The results showed that 65.8% of Shanghai vegetables, 38.2% of Anhui vegetables and 23.6% of Zhejiang vegetables appeared to be grown using green or organic farming methods. The optimal discriminant model was obtained using SVM with a predictive accuracy of 100% for Shanghai vegetables. Zhejiang vegetables had a predictive accuracy of 91.7%, while it was difficult to distinguish Anhui vegetables from Shanghai or Zhejiang vegetables. Therefore, this study provided a useful method to identify vegetable farming methods and discriminate vegetables from Shanghai and Zhejiang.

First Report of Cichorium endivia (Asteraceae) as a Natural Host of Groundnut ringspot orthotospovirus in Brazil

Endive (Cichorium endivia L.) is a very important cash crop for small farmers in Brazil. During inspections conducted in the summer season of 2019-2020, leaf samples of C. endivia 'La Spezia' seedlings exhibiting typical symptoms of orthotospoviruses infection (viz. concentric chlorotic spots and apical leaf deformation; ≈ 10%) were collected in commercial greenhouses in Brasília-DF, Central Brazil. Leaves of one healthy and three symptomatic plants were initially evaluated via double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with polyclonal antibodies (produced at CNPH) raised against the nucleoprotein of the three major orthotospoviruses: tomato spotted wilt orthotospovirus (TSWV), groundnut ringspot orthotospovirus (GRSV) and tomato chlorotic spot orthotospovirus (TCSV). Strong serological reactions were observed only against GRSV antibodies exclusively in extracts from symptomatic samples. In order to confirm the causal agent of those symptoms, total RNA was extracted (Trizol®; Sigma) from infected leaf samples and used in a two-step reverse transcriptase polymerase chain reaction (RT-PCR) approach. Synthesis of the cDNA was carried out with the J13 primer (5'-CCC GGA TCC AGA GCA AT-3') (Cortez et al., 2001) followed by PCR assays with the primer pair BR60 (5'-AGA GCA ATC GTG TCA-3`) and BR65 (5'-ATC AAG CCT TCT GAA AGT CAT-3') (Eiras et al., 2001). This primer set amplifies a fragment of 453 bp including the untranslated region at the 3' terminus of the small RNA and the protein N-coding gene of at least five orthotospoviruses: TSWV, GRSV, TCSV, chrysanthemum stem necrosis orthotospovirus (CSNV) and zucchini lethal chlorosis orthotospovirus (ZLCV) (Eiras et al., 2001). The obtained amplicons (≈ 432 bp) were subsequently subjected to Sanger dideoxy nucleotide sequencing at CNPH. BLASTn analysis showed >99% identity with a wide array of GRSV isolates available in the GenBank. The nucleotide sequence of Tospo #1 (MT215222) and Tospo #3 (MT215224) isolates displayed 100% identity between them, whereas the Tospo #2 (MT215223) isolate displayed one non-synonymous point mutation in the 3' untranslated region in comparison with the former two isolates. Three plants of C. endivia, Capsicum annuum L. cv. Ikeda, tomato (Solanum lycopersicum L.) cv. Santa Clara and its isoline 'LAM-147' (with the Sw-5 resistance gene), Nicotiana rustica L., Lactuca sativa L. ('Vanda' and 'PI-342444') and Gomphrena globosa L. were mechanically inoculated individually with each GRSV isolate in order to confirm their pathogenicity. Chlorotic lesions and mosaic were observed seven days after inoculation of all plant materials, except the tomato inbred line 'LAM-147', which has the Sw-5 gene that confers broad-spectrum resistance to all Brazilian orthotospoviruses (Boiteux and Giordano, 1993). The GRSV infection was confirmed via DAS-ELISA and RT-PCR 15 days after inoculation, using the same set of antibodies and the primer pair BR60 / BR65. Transmission electron microscopy of ultrathin sections from symptomatic leaf tissues, both from field-infected and experimentally inoculated endive revealed the presence of typical orthotospovirus particles, within endoplasmic reticulum cisternae. Natural infection of endive by TSWV has been reported in Greece (Chatzivassiliou et al., 2000) and by TCSV in São Paulo State, Brazil and in Florida, USA (Subramanya Sastry et al., 2019). To our knowledge, it is the first report of GRSV naturally infecting this Asteraceae species in Brazil. Confirmation of GRSV infection of C. endivia plants is a relevant piece of information aiming to design effective disease management strategies. References: Boiteux, L.S. and Giordano, L. B. 1993. Euphytica 71: 151. Eiras, M. et al. 2001. Fitopatol. Bras. 26: 170. Chatzivassiliou, E.K. et al. 2000 Ann. Appl. Biol. 137: 127. Cortez, I., et al. 2001. Arch. Virol. 146: 265. Subramanya Sastry, K., et al. 2019. Encyclopedia of plant viruses and viroids. Springer, New Delhi. https://doi.org/10.1007/978-81-322-3912-3.

First Report of Colletotrichum gloeosporioides Causing Anthracnose on Canna edulis Ker in China

Canna edulis Ker has been an important economic plant in southern China. The tuberous stems are the most valued plant part and in the past were routinely used as animal feeds. In June 2019, leaf spot disease were detected on C. edulis plants in Chengmai, Hainan Province. Symptoms of the disease were characterized by oval-shaped, initially pale to yellow lesions that become necrotic (brown) with yellow borders, As the lesions expanded, the disease could encompass the entire leaves. which were seen as concentric rings typical of anthracnose disease (FigS1-A). A survey of C. edulis plants revealed that the disease caused serious damage during the summer in Hainan Province, with 50 to 60% incidence in plants. To isolate the pathogen, ten pieces of diseased leaf samples were plated and seven pieces yielded fungal colonies after 5 to 6 days of incubation at 25 °C. The Colonies were single-spored to obtain pure cultures. Pure cultures on potato dextrose agar (PDA) appear white to gray, with white margins and aerial hyphae, and the reverse of the colonies was gray to brown (FigS1-B). Conidia were single-celled, hyaline, cylindrical to slightly curved with a rounded apex and truncated base that measured 13.3 to 18.1(length) × 3.7 to 5.5 (width) μm (n=50) (FigS1-C). The morphological characteristics and measurements of this fungal pathogen matched the previous descriptions of Colletotrichum gloeosporioides (Prihastuti et al. 2012). Isolate JO-3 was identicated by molecular analysis, sequences of the internal transcribed spacer (ITS), actin (ACT) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) regions were obtained. These loci were amplified from isolates using the primer pairs ITS1/ITS4 (Mills et al. 1992), ACT-512F/ ACT-783R (Weir et al. 2012) and GDF/GDR (Templeton et al. 1992) respectively. A BLAST search of GenBank showed that the ITS (MN913584), ACT(MN919196) and GAPDH (MN919195) sequences of the isolate were 99% , 100% and 100% homologous with C. gloeosporioides (GenBank accession nos. MH930419, JX009931 and KX885158). Maximum likelihood trees based on concatenated sequences of the three genes were constructed using MEGA7.0. The results showed the strains isolated from C. edulis were closely related to C. gloeosporioides, as supported by high bootstrap values (FigS1-D). Pathogenicity test was performed with isolate JO-3 by depositing 10-µl droplets of a suspension (1 × 106 conidia/ml) on the surfaces of five artificially wounded leaves (a small hole made with a pushpin) of ten healthy 1-year-old C. edulis plants. An equal number of control leaves were inoculated with sterile water to serve as a negative control. The test was conducted three times. Plants were kept at 25°C with 80% humidity and observed for symptom every day. One weeks after inoculation, all the inoculated plants showed symptoms of yellow sunken spots similar to those observed in the field. No symptoms were observed on the controls. The fungus re-isolated from the infected tissues showed the same cultural and morphological characteristics of the strain inoculated, fulfilling Koch's postulates. C. gloeosporioides was previously reported as the causal agent of anthracnose on Hymenocallis littoralis (Zhao et al. 2019), Abelmoschus esculentus (L.) Moench (Shi et al. 2019) and Sorbaria sorbifolia (Li et al. 2019) in China. To our knowledge, this is the first report of anthracnose on C. edulis caused by C. gloeosporioides in China. This disease can seriously affect the yield and quality of C. edulis in China. Given its wide host range, C. gloeosporioides has great potential to become an economically important plant pathogen. The project was partially funded by Hainan Provincial Research Institute of technology development projects (Collection, Evaluation and Domestication Cultivation of Wild Vegetable Germplasm Resources in Hainan), Hainan Provincial Key Laboratory for Vegetables and Biology，Hainan Provincial Engineering Research Center for Melon and Vegetable Breeding, Major scientific and technological projects in Hainan Province(ZDKJ2017001)，Key R & D projects in Hainan Province (ZDYF2019066), The third Survey and Collection of Crop Germplasm Resources in China. References: Mills, P. R., et al. 1992. FEMS Microbiol Lett. 98:137-144 Weir, B. S., et al. 2012. Stud. Mycol. 73:115. Templeton, M.D. et al. 1992. Gene. 122:225. Prihastuti, H., et al. 2009. Fungal Divers. 39:89 C. D. Zhao, et al. 2019. Plant Dis.103:3286 Y. X. Shi, et al. 2019. Plant Dis.103:303 X. Y. Li, et al. 2019. Plant Dis.103:242.

Occurrence of pesticides residues in French beans, tomatoes, and kale in Kenya, and their human health risk indicators

Residue levels of seven commonly used pesticides were determined in random samples of tomatoes, French beans, and kale collected from horticultural farms in Buuri, Imenti North, and Imenti South sub-counties in Meru, Kenya, just before delivery to the consumers. QuEChERS method for extraction followed by LC-MS/MS was used to determine the concentrations. The concentrations (μg kg^-1 wet weight) in French beans, kale, and tomatoes ranged from below detection limit (BDL): BDL-48.65 (carbendazim), BDL-290.76 (imidacloprid), BDL-2.81 (acetamiprid), BDL-25.76 (azoxystrobin), BDL-105.18 (metalaxyl), BDL-0.15 (diazinon), and BDL-0.17(chlorpyrifos). The maximum residue levels determined in the horticultural produce from the three regions were 290 μg kg^-1 for imidacloprid in tomatoes from Buuri and 25.76 μg kg^-1for azoxystrobin in French beans from Imenti South. The pesticide residue levels generally were extremely low and met the MRLs set by EU and other countries, except for carbendazim and metalaxyl in French beans, and posed no concern to human health. The estimated daily intakes (EDI) (mg kg^-1 BW/day) for the population of Meru County were very low ranging from 1.685 × 10^-8 (acetamiprid) to 2.381 × 10^-5 (imidacloprid) in tomatoes, 2.849 × 10^-9 (metalaxyl) to 3.633 × 10^-7 (azoxystrobin) in French beans, and 1.392 × 10^-8 (diazinon) in kale, respectively. The health risk indices were subsequently extremely low for the detectable pesticide residues, ranging from 6.74 × 10^-7 (acetamiprid) to 3.97 × 10^-4 (imidacloprid) in tomatoes, 3.56 × 10^-8 (metalaxyl) to 5.52 × 10^-5 (chlorpyrifos) in French beans, and 6.96 × 10^-5 (diazinon) in kale, respectively, indicating no health risk in the population, but their presence in these vegetables cannot be ignored as long-term exposure can still cause health risks.

Urban kitchen gardens: Effect of the soil contamination and parameters on the trace element accumulation in vegetables - A review

Trace element contaminants in kitchen garden soils can contribute to human exposure through the consumption of homegrown vegetables. In urban areas, these soils can be contaminated to various degrees by trace element (TE). They are characterized by a great variability in their physicochemical parameters due to the high anthropization level, the wide variety and combination of disturbance sources, as well as the diversity of cultivation practices and the large range of contamination levels. Pollutants can be taken up by vegetables cultivated in these soils and be concentrated in their edible parts. In this review, the behavior of vegetables cultivated in contaminated kitchen gardens is assessed through six examples of the most widely cultivated vegetables (lettuce, tomato, bean, carrot, radish, potato). The role of soil parameters that could influence the uptake of As, Cd, Cr, Ni, Pb, and Zn by these vegetables is also discussed.

Mitigation of chromium (VI) toxicity by additional sulfur in some vegetable crops involves glutathione and hydrogen sulfide

Toxic metals cause substantial reduction in crop yields every year. Therefore, worldwide scientific efforts are being made to reduce such losses in crop productivity by using certain chemical protectants such as nutrients like sulfur (S), hydrogen sulfide (H₂S), glutathione (GSH), etc. Therefore in this study, we have tested potential of additional S, along with probable involvement of H₂S and GSH in mitigating hexavalent chromium (CrVI) toxicity in tomato, pea and brinjal seedlings. Chromium (VI) decreased shoot and root length, endogenous H₂S, and cell viability due to greater Cr accumulation that led to cell death in roots. Chromium (VI) enhanced oxidative stress markers i.e. superoxide radical, hydrogen peroxide, lipid peroxidation and protein oxidation due to down-regulation in ascorbate-glutathione cycle. However, additional S reversed toxic effect of Cr(VI). Chromium (VI) slightly stimulated enzymes of glutathione biosynthesis. Besides this, the results also showed that addition of buthionine sulphoximine (BSO, synthetic inhibitor of glutathione biosynthesis) interestingly further enhanced Cr(VI) toxicity even in the presence of additional S. But this effect of BSO was reversed by the addition of GSH. Interestingly, hydroxylamine (HA, synthetic inhibitor of cysteine desulfhydrase) had also further increased Cr(VI) toxicity even in the presence of additional S but sodium hydrosulfide (NaHS, an H₂S donor) reversed this effect. Furthermore, ameliorative behaviour of NaHS against Cr(VI) toxicity was reversed by the hypotaurine (HT, a H₂S scavenger). All together results suggested that additional S involved GSH and H₂S in mitigating Cr(VI) toxicity in studied vegetables, in which GSH acted downstream of H₂S signal.

Evaluation of Chemical and Microbiological Contaminants in Fresh Fruits and Vegetables from Peasant Markets in Cundinamarca, Colombia

ABSTRACT

In this study, chemical and microbiological contaminants were detected in fresh fruits and vegetables in peasant markets in the Department of Cundinamarca to assess food safety. At least one pesticide was detected in 63% of the samples evaluated (n = 100, including fruits and vegetables), and in 41% of these, pesticides exceeded the maximum residue limit. Within the pesticides found, 60% do not use a registry from the Instituto Colombiano Agropecuario to be applied on the crops where they were detected and are included in the toxicological categories "highly toxic" (category IB) and "moderately toxic" (category II). Heavy metals were found in 45% of the samples, with cadmium (38%) and lead (14%) being the most frequent. The pathogenic microorganisms Escherichia coli O157:H7, Listeria monocytogenes, Salmonella, and Campylobacter sp. were detected in 4, 2, 1, and 0% of the samples, respectively. Factors concerning integrated crop management, contaminated inputs with chemicals and microorganisms, and the lack of hygiene in the postharvest stage favor the presence of pesticide residues, heavy metals, and the appearance of pathogenic microorganisms. The results suggest the need to strengthen the implementation of integrated management strategies that guarantee the safety of fresh fruits and vegetables in the country.

HIGHLIGHTS

The harmonizing effect of Smart Snacks on the association between state snack laws and high school students' fruit and vegetable consumption, United States-2005-2017

Despite national guidelines recommending daily fruit and vegetable (FV) consumption, intake of FV among adolescents is low. Over the past 10-15 years, state and federal laws have reduced the availability of junk foods in schools. This study examined the association between state snack laws and high school (HS) student FV consumption. The overall sample included 99,785 HS students (outcome samples ranged from 96,209-97,328) included in the Youth Risk Behavior Survey (YRBS). National Cancer Institute Classification of Laws Associated with School Students' data for 2004-2016 were lagged on to 2005-2017 YRBS data. Separate analyses examined the state law-youth FV consumption relationship pre- and post-federal Smart Snacks standards (effective school year 2014-2015). Analyses were conducted between 2018 and 2020. Overall, state laws were associated with any vegetable, salad, and other vegetable consumption. The relationship between state laws and vegetable consumption primarily occurred pre-Smart Snacks. Pre-Smart Snacks, state laws were associated with higher odds of youth consumption of any vegetable, salad, carrots, and other vegetables (all compared to students in states without snack laws). The only association post-Smart Snacks was between strong state laws and salads. This study illustrates the important role that standards restricting the availability of junk foods in schools can have on increasing student vegetable consumption. Given current efforts to roll-back federal school meal standards, findings from this study illustrate how federal standards harmonized the patchwork of state laws that existed prior to Smart Snacks and the important role that consistent national standards can play in supporting student consumption of vegetables.

First Report of Powdery Mildew Caused by Podosphaera xanthii on Hulless Cucurbita pepo of Inner Mongolia and Xinjiang Autonomous Region in China

Hulless Cucurbita pepo is an annual herb in the Cucurbitaceae family and is one of the main economic vegetable crops in China, and is a raw material for cosmetics and health care products. It is also called hulless pumpkin because its seeds have no seed coat, which is a rare variation of the Cucurbita. In July 2010, powdery mildew was observed on hulless Cucurbita pepo 'Tianran' in fields of Wuwei District, China(Liang et al.2010). Disease incidence when first observed was 65.67%, but increased to 100% in July 2019. Early disease symptoms appeared as circular or irregular white powdery areas on both leaf surfaces. At later infection stages, entire leaves，petioles, and stems were covered with white fungal mycelia that resulted in leaf yellowing and senescence，but not defoliation . Fungal hyphae were septate, branched and flexuous to straigh. Conidiophores were unbranched, straight and grew vertically to the mycelium. Conidiophore foot cells of the were cylindrical with slight constriction at basal septa and followed by one to four short cells that eventually became conidia. Conidia were barrel-shaped with ends darker than the middle and measured 20 to 32 × 12 to 19μm.T Cleistothecium formed at 20 ℃, 70% relative humidity and light intensity of 4,400 lx. They were scattered, spherical, dark brown, with parietal cells irregularly rectangular or polygonal, and 70 to 75×90 to 95μm in diameter. Cleistothecia had four to eight appendages that were colorless to partially brown, each with three to five septa and lengths 0.5 to 3.0 times the diameter of cleistothecia. The powdery mildew fungus was tentatively identified as Podosphaera xanthii and showed characteristics similar to those reported by others (Cui et al. 2018; Choi et al. 2020). rDNA was extracted from pools of fungus conidia and the ITS region amplified using primers ITS 1:5'-TCCGTAGGT GAACCTGCGG-3'/ITS 4:5'-TCCTCCGCTTATTGATATGC-3' and then sequenced. BLASTn analysis of the 540-bp (MT250855) amplicon revealed 100% sequence identity with respective rDNA sequences of Podosphaera xanthii isolates from Momordica charantia(AB774158.1). Based on the morphological characteristics and ITS sequences, the fungal species was identified as P. xanthii .Pathogenicity of the powdery mildew fungus was tested by dusting conidia from infected hulless pumpkin leaves onto three asymptomatic plants. Three noninoculated plants was used as a controls. The Infection process of P.xanthii on pumpkins observed that the conidia began to germinate at 12h after inoculation.Twenty four to 72 h post inoculation, powdery mildew mycelia appeared on inoculated leaves. After 73 to 96 h, chains of conidia formed and these germinated to form secondary infection sites. In later stages of the disease cycle, dark brown cleistothecia formed on the yellowing plant foliage. Fungus morphology from inoculated leaves was identical to that observed on original naturally infected plants. Uninoculated plants remained healthy. Powdery mildew caused by P. xanthii is a major foliage disease that affects members of the Cucurbitaceae family worldwide. The fungus has previously been reported from China on Cucurbita moschata (DQ490752), Cucurbita maxima (DQ490759), Cucurbita pepo(DQ490750), Cucumis sativus(DQ490755)(Park et al.2010; Liang et al.2007) and Cucurbita maxima, Abelmoschus esculentus (okra), Sechium edule (mirliton, vegetable pear), and Lagenaria siceraria (bottle gourd) (Choi et al. 2020; Fan et al. 2019; Xu et al. 2020; Cui et al. 2018).To our knowledge, this is the first report on the occurrence of P. xanthii on hulless Cucurbita pepo in China.

First report of Tomato brown rugose fruit virus in tomato in Spain

In October 2019, tomato (Solanum lycopersicum L.) plants showing chlorosis and brown necrosis in apical leaflets and rugose surface in fruits were observed in a greenhouse in Vicar, Almería, Spain. A total of 0.5% of the tomato plants in the greenhouse (1,38 ha) showed these symptoms. The presence of tomato brown rugose fruit virus (ToBRFV) was suspected. A total of 5 symptomatic and 2 symptomless leaf samples were collected and analyzed by double-antibody sandwich (DAS)-ELISA with antibodies for ToBRFV, tobacco mosaic virus (TMV) and tomato mosaic virus (ToMV) (Loewe Biochemica, Germany). Symptomatic samples tested positive by DAS-ELISA only for ToBRFV. Therefore, one sample was selected and analyzed by reverse transcription (RT)-PCR with specific primers ToBRFV-F5722/ToBRFV-R6179 for ToBRFV (Panno et al. 2019a) which amplified a 458 bp fragment of the coat protein gene. The sequence obtained by Sanger sequencing from the amplicon showed 99.7% nt identity with ToBRFV isolate from United Kingdom (Acc. No. MN182533) and was deposited in the GenBank database under the accession number MT211630. Further surveys were performed in Vicar and El Egido (Almería, Spain) on plants showing viral-like symptoms. A total of 50 tomato and two pepper leaf samples from 28 greenhouses were collected and analyzed by DAS-ELISA for ToBRFV, TMV, ToMV, pepino mosaic virus (PepMV) , tomato spotted wilt virus (TSWV) and tomato yellow leaf curl virus (TYLCV) with respective antibodies (Loewe Biochemica, Germany). Five tomato plants (four from Vicar and one from El Ejido) tested positive for ToBRFV. PepMV, ToMV and TYLCV were also detected in one, three and five tomato plants, respectively. The ELISA positive results for ToBRFV were confirmed by end point RT-PCR with primer pairs ToBRFV-F5722/ToBRFV-R6179 and ToBRFV-F/ToBRFV-R (Alkouni et al., 2019) and by real-time RT-PCR with Taqman probe ToB-probe and specific primers ToB5520F/ToB5598R (Panno et al., 2019b). Tomato seeds used for plantation in these greenhouses were also analyzed, but ToBRFV was not detected. Eradication measures have been undertaken to prevent the virus spread and to control this outbreak. Official seed analysis by DAS-ELISA and real time RT-PCR (ISF, 2019) are being conducted on the tomato and pepper imported seeds to prevent the appearance of new sources of ToBRFV inoculum in Spain. References: Alkowni, R., et al. 2019. J. Plant Pathol. 101: 719. doi: 10.1007/s42161-019-00240-7. ISF, 2019. International Seed Federation. Version 1.3, September 2019. Available at https://www.worldseed.org/wp-content/uploads/2019/09/Tomato-ToBRFV_2019.09.pdf Panno, S., et al. 2019a. Plant Dis. 103: 1443. https://doi.org/10.1094/PDIS-12-18-2254-PDN Panno, S. et al. 2019b. PeerJ 7:e7928 DOI 10.7717/peerj.7928.

Detection of herbicide clopyralid at nanogram per gram level in agricultural products using easy-to-use micro liquid-liquid extraction followed by analysis with ultraperformance liquid chromatography-tandem mass spectrometry

A new sample preparation method was developed for auxin-like herbicide clopyralid residue in agricultural products. The method uses extraction with sulfuric acid - acidified acetonitrile, with cleanup of sample extracts using solid-phase extraction (diatomaceous earth) and micro liquid-liquid extraction, followed by ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). This sample preparation method greatly reduces the influence on ionization during determination with UPLC-MS/MS. Quantification was achieved using external calibrators prepared in matrix-free 0.1% formic acid. The proposed analytical method supported good recovery of 73.7-91.4% with less than 8% relative standard deviation. Method quantification limits (MQL) of samples were 0.6-1.0 ng g-1. The method was applied to determine clopyralid residue in several crop samples. The herbicide was detected as near the MQLs in all samples.

First report of Fusarium proliferatum causing necrotic leaf lesions and bulb rot on storage onion (Allium cepa) in southwestern Idaho

In September 2014, a high rate of bulb rot (5-15% depending on producer) was reported across all cultivars developing early in the storage season in the onion producing region of southwestern Idaho. Spanish yellow onion bulbs cv. Vaquero displaying tan to light brown necrotic rot were obtained. The bulb rot originated in the neck and spread to successive scales (Figure 1). In August 2015, onion cv. Redwing and Vaquero were observed to have wet necrotic lesions developing on leaves in the field (Figure 2). Margins of necrotic tissue, 1-2 cm3, were excised, surface sterilized, plated on water agar medium and incubated at 24°C. Hyphal growth was sub-cultured from eight strains (A- D in 2014; E-H in 2015) to fresh potato dextrose agar to obtain pure cultures. Cultures were characteristic of Fusarium species as described by Nelson et al. (1983) with the presence of microconidia formed on polyphialides with macroconidia present. Primers ITS4-A1 and ITS5 primers (White et al. 1990); EF-1 and EF-2 (O'Donnell et al. 1998); and fRPB2-5F and fRPB2-7cR (Liu et al. 1999) were used to amplify regions of the ITS, elongation factor 1-α and the second largest subunit of DNA-directed RNA polymerase II. Amplicons were sequenced and analyzed using BLAST (https://www.ncbi.nlm.nih.gov/) and in combination using Pairwise DNA Alignment and Polyphasic Identification (http://www.westerdijkinstitute.nl/Fusarium/DefaultInfo.aspx?Page=Home) as described by O'Donnell et al. 2015. Analysis indicated that these strains are Fusarium proliferatum, which is part of the F. fujikuroi species complex (O'Donnell et al. 1998). Similarity (99.5%) was observed in pairwise analyses and the polyphasic identification clustering to representative F. proliferatum strain NRRL 22944 and others. Sequences were submitted to Genbank and registered accession numbers are found in Table 1. To complete Koch's postulates, cv. Vaquero onion bulbs were surface sterilized and injected with 3 × 105 microconidia into the shoulder of each bulb. Five bulbs were inoculated for each isolate, placed in a mesh bag, and incubated at 30°C in the dark. Five bulbs injected with sterile water and five non-inoculated bulbs served as controls. After 14 days, each bulb was sliced vertically down the center and inspected for rot. All eight strains induced tan to light brown necrotic rot symptoms in each inoculated bulb. No symptoms were observed for the water inoculated and the non-inoculated onion bulbs. A fungus was isolated from the necrotic tissue and confirmed to be F. proliferatum as described above. Ten µl aliquots containing 1 × 105 microconidia of F. proliferatum strains (C, E-H) were applied to leaves in triplicate of 12-week-old onion plants (cv. Vaquero) wounded with a 21-gauge needle. Water controls were included. Within three days lesions, with light chlorosis, began to form and quickly spread on the leaves. A fungus was isolated and confirmed to be F. proliferatum as described above. This is the first extensive description and identification of F. proliferatum causing bulb rot in storage in Idaho (Mohan et al. 1997). In addition, this is the first report of the fungus causing leaf infection in the field. These findings confirm F. proliferatum as the causal agent of the high incidence of bulb rot observed in 2014 and 2015. This bulb rot continues to occur in southwestern Idaho and since the pathogen can cause leaf infections growers are encouraged to be vigilant for both leaf lesions during the growing season and bulb rot in storage.

Agent-based modeling insights into the optimal distribution of the Fresh Fruit and Vegetable Program

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Agent-based modeling assists in disseminating FFVP in the most cost-effective manner.

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Early childhood exposure to fruits and vegetables is more effective in influencing preferences than later exposure.

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More consistent exposure to a fruit and vegetable intervention is more effective than sporadic exposure.

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Children living in food deserts may benefit most from FFVP.

The Fresh Fruit and Vegetable Program (FFVP) program provides a free fresh fruit or vegetable snack to children in low-income schools between two and five times a week. This is an important nationwide program, but current funding levels are insufficient to reach all eligible schools. Thus, there is a need to develop insight on contextual factors that may impact the effectiveness of FFVP in facilitating the development of childhood food preferences. An agent-based model of preference formation is used to understand how exposure to FFVP in early elementary school may affect preferences for healthy food by 6th grade. Preferences are modeled using the temporal difference learning algorithm used by Hammond et al. (2012). This model simulates habit formation in the context of food by modeling preference formation in terms of positive or negative feedback about the food most recently consumed. The model is designed to provide insights into how different patterns of exposure to FFVP affect preferences, and how living in a food desert changes the effect of FFVP. We use data on 35,981 students from Arkansas elementary schools (from 2008 to 2016) and information about the commercial food environment in Arkansas communities to populate the model. We find that early FFVP exposure is more beneficial than late exposure conditional on the number of years exposed. We also find that FFVP is more beneficial for children who grow up in environments lacking healthy food.

Comparison of food and beverage products' availability, variety, price and quality in German and US supermarkets

Objective:

To assess availability, variety, price and quality of different food products in a convenience sample of supermarkets in Germany and the USA.

Design:

Cross-sectional study using an adapted version of the Bridging the Gap Food Store Observation Form.

Setting:

Information on availability, quality, price and variety of selected food products in eight German and seven US supermarkets (discount and full service) was obtained and compared by country.

Results:

A general tendency for lower prices of fruits and vegetables in Germany was observed, while produce quality and variety did not seem to differ between countries, with the exception of the variety of some vegetables such as tomatoes. Chips and cereals did not differ significantly in variety nor price. In both countries, high energy-dense foods were lower in energy costs than lower energy-dense foods.

Conclusions:

The influence of food prices and availability on consumption should be further explored, including the impact of country differences.

The data set on vertical distribution pattern of Bemisia tabaci genn. (Homoptera: Aleyrodidae) in several vegetable crops

Bemisia tabaci is one of the main pests of vegetable crops in the tropics, including in Indonesia. The vertical distribution pattern of B. tabaci on investigated vegetable plants can be used to establish a sample observation unit in monitoring activities of pest control management. This data showed the vertical distribution pattern of B. tabaci on vegetable plants gathered from two different locations, namely from the high land of Ciwidey District, Bandung City (string bean, kidney bean, and tomato) and the low land of Sliyeg District, Indramayu City (eggplant, towel gourd, cucumber, and long beans). The data of B. tabaci nymph population were then analyzed to determine vertical distribution patterns.

Effect of a free healthy school meal on fruit, vegetables and unhealthy snacks intake in Norwegian 10- to 12-year-old children

BACKGROUND

Norwegian children have a lower intake of fruit, vegetables, and a higher intake of unhealthy snacks compared to dietary guidelines. Such dietary inadequacies may be detrimental for their current and future health. Schools are favorable settings to establish healthy eating practices. Still, no school meal arrangement is provided in Norway, and most children typically bring packed lunches from home. The aim of this study was to investigate whether serving a free healthy school meal for one year resulted in a higher intake of fruit and vegetables and a lower intake of unhealthy snacks in total among 10-12-year-olds in Norway.

METHODS

The School Meal Project in Southern Norway was a non-randomized trial in two elementary schools in rural areas in the school year 2014/2015. The study sample consisted of 10- to 12-year-old children; an intervention group (N = 55) and a control group (N = 109) resulting in a total of 164 school children at baseline. A food frequency questionnaire was completed by the children at baseline, at five months follow-up and after one year to assess fruit, vegetable, and snacks intake. Multiple linear regression analyses were performed to assess intervention effects on overall intake of fruit and vegetables and unhealthy snacks.

RESULTS

Serving of a free healthy school meal for one year was associated with a higher weekly intake of vegetables on sandwiches in the intervention group compared to the control group, adjusted for baseline intake (B: 1.11 (95% CI: .38, 1.85)) at the end of the intervention. No other significant intervention effects were found for the remaining fruit and vegetables measures. Serving of a free healthy school meal was not associated with a lower weekly intake of unhealthy snacks (i.e. potato chips, candy, sugar sweetened beverages) in the intervention group compared to the control group.

CONCLUSIONS

A free healthy school meal was associated with a higher weekly intake of vegetables on sandwiches but did not significantly change any other investigated dietary behaviors. However, given the inadequate intake of vegetables among children and that even moderate improvements have public health relevance, a free healthy school meal for all school children could be beneficial.

TRIAL REGISTRATION

ISRCTN61703361 . Date of registration: December 3rd, 2018. Retrospectively registered.

Microbiological safety of ready-to-eat fresh-cut fruits and vegetables sold on the Canadian retail market

Following implementation of Health Canada's Policy on Listeria monocytogenes in Ready-to-Eat Foods by Canadian food safety authorities in 2011, a four-year study (2012-2016) was carried out to gain baseline information on the occurrence of bacterial pathogens, notably the prevalence and levels of Listeria monocytogenes (L. monocytogenes) in various product types of ready-to-eat (RTE) fresh-cut fruits and fresh-cut vegetables sold at retail in Canada. A total of 10,070 pre-packaged samples, including 4691 fresh-cut fruit and 5379 fresh-cut vegetable samples were collected from retail stores across Canada and analyzed for bacterial pathogens and generic Escherichia coli (E. coli). Salmonella species (spp.), E. coli O157:H7, Shigella and Campylobacter were not detected in any of the tested samples. L. monocytogenes was identified in 0.51% (95% CI [0.34, 0.76]) of the fresh-cut fruit and in 0.24% (95% CI [0.14, 0.41]) of the fresh-cut vegetable samples. Of the 37 L. monocytogenes positive samples identified, levels of L. monocytogenes <5 CFU/g, 5-<100 CFU/g, and ≥100 CFU/g were found in 67.6% (25/37), 24.3% (9/37) and 8.1% (3/37) of the samples, respectively. The results of this study indicate that the vast majority of fresh-cut fruits and vegetables sold on the Canadian retail market are safe for consumption. However, contamination by L. monocytogenes can infrequently occur in fresh-cut fruits and vegetables, with certain types of fresh-cut fruits (i.e., melons, apples) and vegetables (i.e., mushrooms, cauliflower) being more likely to be contaminated than others. Safe handling practices are recommended for producers, retailers and consumers including storage at refrigerated temperatures.

Natural Infection of Tomatoes (Solanum lycopersicum) by Euphorbia yellow mosaic virus Isolates across Four Brazilian States

Severe yield losses induced by a complex of whitefly-transmitted Begomovirus species (family Geminiviridae) have been reported in tomatoes in Brazil (Reis et al. 2020). Nine isolates were obtained from tomato plants exhibiting begomovirus-like symptoms (viz. apical and interveinal chlorosis, yellow spots, and stunting) during independent field surveys: one isolate in Sumaré, São Paulo-SP State (isolate SP-066) in 2001, two in Serra Negra, Minas Gerais-MG (MG-012 and MG-016) in 2002, five in Caxias do Sul, Rio Grande do Sul-RS (RS-039, RS-045, RS-046, RS-047 and RS-058) in 2011 and one in Domingos Martins, Espírito Santo-ES (ES-148) in 2016. Disease incidence across all sampled fields ranged from 30% (in Domingos Martins-ES) to 90% in Sumaré-SP. Total DNA extraction was done by a modified CTAB method (Boiteux et al., 1999). Begomovirus infection was confirmed in all isolates by selective amplification of viral DNA-A segments using the primer pairs 'PAL1v1978 / PAR1c496' (Rojas et al., 1993) and 'BegomoAFor1' / 'BegomoARev1' (Ha et al., 2006), which produce two large and non-overlapping segments (≈1120 bp and ≈1205 bp, respectively). These PCR amplicons were initially characterized via direct Sanger dideoxy sequencing at CNPH. BLASTn analysis of the partial DNA-A genomes of these nine isolates indicated identity levels of 95-97% to three euphorbia yellow mosaic virus (EuYMV) reference isolates (= KY559532, JF756674, and KY559583) found infecting the weed Euphorbia heterophylla L. The entire DNA-A (2,609 nts = MN746971) and DNA-B (2,579 nts = MN746970) components of the MG-016 isolate were obtained via high-performance sequencing using Illumina HiSeq 2500 system (Macrogen Inc., South Korea). Sequences were assembled with the CLC Genomics Workbench program 10. Contigs were validated by BLASTx and BLASTn and compared to the ssDNA virus database at NCBI (www.ncbi.nlm.nih.gov). The fully-characterized MG-016 isolate displayed identity levels ranging from 97 to 99% to the EuYMV reference isolates as well as similar genomic features such as the conserved TATA box, nonanucleotide, and iterons (that were in agreement with a cognate nature of the DNA-A and DNA-B components). A partial sequence of the DNA-B genome was also obtained for the MG-012 isolate (MT7831942). The isolates MG-012 and MG-016 were found in mixed infections with tomato severe rugose virus (ToSRV) and tomato golden vein virus (TGVV), respectively. In addition, the complete DNA-A genomes of ES-148 (MN746972) and SP-066 (MN782438) were also obtained via a combination of primer walking and Sanger dideoxy sequencing, displaying 96-98% identity to EuYMV isolates. To our knowledge, this is the first report of multiple and independent events of natural infection of tomatoes by EuYMV isolates. Our results confirm the natural host status of tomatoes to EuYMV isolates as indicated in previous infectivity assays using biolistic inoculation (Barreto et al., 2013). The weed E. heterophylla is widely disseminated and very often present within tomato fields due to its higher levels of tolerance to the major herbicide (metribuzin) employed in this crop. Therefore, this weed may act as a persistent reservoir of tomato-infecting EuYMV isolates, which may allow the selection of viral populations potentially more adapted to this vegetable crop.