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We announce the sequence of the Escherichia coli MTR_GS_S1457 strain isolated from a soil sample of a vegetable gardening system for the first time in Bangladesh. With a length of 4,918,647 bp, this strain contained one plasmid, two CRISPR arrays, 54 predicted antibiotic resistance genes, and 81 predicted virulence factor genes.

This study announces the genome sequence of the Shigella flexneri MTR_GR_V146 strain isolated from a tomato (Solanum lycopersicum) sample in Bangladesh. This strain has a 4,624,521 bp genome length (coverage: 73.07×), 2 CRISPR arrays, 1 plasmid, 52 predicted antibiotic resistance genes, and 53 virulence factor genes.

We announce a genome sequence of Citrobacter freundii MTR_GS_V1777 strain isolated from a vegetable sample in Bangladesh. This strain had a genome size of 4,997,753 bp (58.7× genome coverage) and contained two plasmids, typed as sequence type ST124, 38 predicted antibiotic resistance genes, and 77 predicted virulence factor genes.

Reports indicate that vegetables are becoming a source of multidrug-resistant (MDR) bacteria, including Escherichia coli. Here, we present genome sequences of five MDR E. coli strains to assist future genomic analysis of this bacterium. These E. coli strains were isolated from vegetable samples of different gardening systems in Dhaka, Bangladesh.

Tomatoes are one of the predominant vegetable crops grown throughout the year in Tamil Nadu, India. Their perishable nature and resource-intensive cultivation make them susceptible to biotic stress. The damage caused by invasive insect pests, bacterial wilt during the rainy season, and viral diseases are major yield-limiting factors, and the farmers mostly depend on calendar-based insecticide applications for insect pest and disease management in tomatoes. The desired tomato hybrids grafted onto bacterial wilt-resistant eggplant rootstocks offer protection against bacterial wilt during the rainy season. The integrated pest and disease management (IPDM) practices consist of resistant grafted tomato seedlings (wild eggplant rootstocks EG 203 and TS 03), bioinoculants (Bacillus subtilis + Trichoderma asperellum + Purpureocillium lilacinum), pheromone traps (Phthorimaea absoluta and Helicoverpa armigera), botanicals (azadirachtin), microbial pesticides (Bacillus thuringiensis, Metarhizium anisopliae, and Beauveria bassiana), and bio-rationals, which were evaluated in four locations in two major tomato-growing tracts of Tamil Nadu. The results revealed that the treatment EG 203 eggplant rootstock-grafted tomato along with IPDM practices performed better across all experimental locations than the other treatment combinations viz., TS 03 eggplant rootstock-grafted tomato + IPDM, tomato + IPDM, grafted tomato + farmers’ practice and tomato + farmers’ practice. The EG 203-grafted tomato recorded a higher yield than the farmers’ practice with significantly superior biometric parameters. The treatment of EG 203-grafted tomato and IPDM practices can be adopted for safer tomato production by enabling a reduction in pesticide applications while enhancing productivity.

BackgroundThe value chains of tomatoes in Ethiopia are largely informal which may pose potential food safety risks. Value chains (VCs) mapping was carried out with emphasis on tomatoes in two major cities in eastern Ethiopia—Harar and Dire Dawa—which were assessed to identify practices likely to result in unsafe food, considering production, transportation, retail, preparation, and consumption.MethodsQualitative methods were used to map the VCs to understand the flows, actors, and practices. Group discussions and key informant interviews were performed to better understand the processes, practices, beliefs, and food safety risks in these VCs.ResultsThe two cities are supplied by two vegetable VCs: the first and larger being from distant producers in central Ethiopia, and the second from surrounding rural and peri-urban producers. The long-distance VCs involve producers, brokers, transporters, wholesalers, retailers, and consumers. The local producers, however, bring their fresh products directly to the cities without the involvement of VC actors other than final retailers and consumers. The study suggests microbiological contamination risks along tomato VCs, potentially including soil contamination, use of sewerage-contaminated irrigation water, untreated manure, unhygienic handling and storage conditions, and dirty contact surfaces during transportation and retailing. Tomatoes are mostly harvested by hand picking, collected, and sorted on the ground exposing to sunlight and physical bruising with potential contamination. More importantly, tomatoes are widely consumed raw without “a kill-step” that certainly contributes to food-borne infections. Suggestions by study participants for improving food safety and hygiene include funding toward improved infrastructure and facilities in the sectors, supporting VC actors with improved technology for quality production, and increasing awareness of good and hygienic practices. Consumers were particularly concerned about contamination with agrochemicals without much emphasis on the potential microbial contaminants. Fresh tomatoes are prepared in a variety of ways and are often consumed raw or slightly cooked. Further recommendations included using health extension workers to conduct awareness campaigns on improved food safety and hygienic practices.ConclusionThe qualitative VC mapping generated useful information for designing intervention strategies, especially targeting developing food safety interventions and an awareness communication campaign.

BackgroundIn Ethiopia, pesticides are widely used in vegetable production. However, if used incorrectly they may harm consumers of vegetables contaminated with pesticide residues, as well as producers handling the pesticides and lead to ecological damage. We performed a cross-sectional survey to assess pesticide residues in vegetables produced in central and eastern Ethiopia.MethodsA total of 232 vegetable samples (91 tomatoes, 106 cabbages and 35 Swiss chard) were collected from fields and retail markets, and were screened for 35 pesticides (16 organochlorine, 11 organophosphate, 3 pyrethroids, 2 carbamates and 3 other agrochemicals) using GC–MS analysis.ResultsPesticides residues were detected in 60% of Swiss chard, 47% of cabbage and 45% of tomato samples. Two or more pesticides were detected in 20% of cabbages, 13% of tomatoes and over half of Swiss chard samples. Bendiocarb, diazinon, endrin, piperonyl butoxide, profenofos and propargite were detected, but only diazinon, propargite and profenofos had residual values above EU Maximum Residue Level (MRL), with diazinon commonly detected at relatively high levels. About 15% of the total analyzed samples, 10% of cabbages and tomatoes, and nearly half of Swiss chard samples had pesticide concentration exceeding EU MRL. However, none of the tested samples had residues exceeding Codex Alimentarius Commission (Codex) MRLs.ConclusionThis study showed widespread contamination of vegetables with pesticides, mainly organophosphates. We recommend monitoring and regulation of pesticides usage, with promotion of good agricultural practices.

India experienced a rapid rise in COVID-19 infections from March 2021. States imposed varying levels of lockdowns and curfews to curb the spread of the disease. These restrictions severely affected the functioning of food systems. The objective of this study was to analyze how COVID-19 continues to affect agricultural production, food security and household diets of vegetable farmers. A phone-based survey was conducted with 595 vegetable farmers in the states of Andhra Pradesh, Assam, Jharkhand, Karnataka and Odisha, 60% of whom had been interviewed a year earlier. Overall, 60% of farmers experienced decreased vegetable production; over 80% reported a reduction in consumption of at least one food group; and 45% reported some level of food insecurity between May 2020 and May 2021. Farmers who reported decreased staples production, difficulty accessing seeds/seedlings, or reduced their household spending were more likely to report decreased vegetable production. Vegetable consumption was positively associated with receipt of COVID-19 relief benefits, borrowing money, or having home gardens. Farmers who received public agricultural assistance, or had reduced expenses, were more likely to have lower vegetable consumption. Greater severity of food insecurity was associated with farmers belonging to underprivileged social groups, non-Hindus, or those who experienced decrease in livestock production, weather related disruptions or received COVID-19 assistance. This is one of few studies that have conducted a longitudinal assessment of the impacts across multiple waves of COVID-19. COVID-19 is seen to be one among several shocks experienced by farm households, and exacerbated existing issues within agriculture and food security. There is a need for public policy support to strengthen both production and consumption of vegetables.

Abstract Therophilus javanus (Bhat & Gupta) is an exotic larval endoparasitoid newly imported from Asia into Africa as a classical biological control agent against the pod borer Maruca vitrata (Fabricius). The parasitoid preference for the five larval instars of M. vitrata and their influence on progeny sex ratio were assessed together with the impact of larval host age at the time of oviposition on development time, mother longevity and offspring production. In a choice situation, female parasitoids preferred to oviposit in the first three larval instars. The development of immature stages of the parasitoid was observed inside three-day-old hosts, whereby the first two larval instars of T. javanus completed their development as endoparasites and the third larval instar as ectoparasite. The development time was faster when first larval instars (two- and three-day-old) of the host caterpillars were parasitized compared to second larval instar (four-day-old). The highest proportion of daughters (0.51) was observed when females were provided with four-day-old hosts. The lowest intrinsic rate of increase (r) (0.21 ± 0.01), the lowest rate of increase (λ) (1.23 ± 0.01), and the lowest net reproductive rate (Ro) (35.93 ± 6.51) were recorded on four-day-old hosts. These results are discussed in the light of optimizing mass rearing and release strategies.

Invasive tomato leaf miner, Phthorimaea absoluta causes serious damage and yield loss in tomato production in open-field and protected cultivation. Use of chemical pesticides is uneconomical and adversely affects humans and the environment. Host-plant resistance is an effective, economical and eco-friendly alternative to chemical pesticides. In this study, four wild tomato accessions from the World Vegetable Center along with one susceptible check were evaluated for their antixenosis and antibiosis effects on P. absoluta. The accessions VI037241 (Solanum galapagense) and VI037240 (S. cheesmaniae) were highly resistant, leading to 85% larval mortality under no-choice conditions. Choice assay also showed less oviposition preference and reduced pupal weight. Both VI037241 and VI037240 showed the highest resistance under field conditions. The accessions of S. habrochaites (LA1777) and S. habrochaites var. glabratum (VI030462) demonstrated moderate resistance against P. absoluta. Wild accessions recorded significantly less eggs and leaf damage in field trials compared to the susceptible genotype, S. lycopersicum (CL5915). Trichome density, type and higher production of acylsugar contributed to the insect resistance. Acylsugar production in wild accessions was less during the rainy season but significantly higher than in susceptible genotype. These findings can be useful to develop P. absoluta-resistant tomato varieties in tropics.

Globally, Soil erosion is the major land degradation problem, which impacts seriously on economic and environmental status. Geospatial techniques support and provided quantitative approach to estimate soil erosion in different conditions. In the present study, Revised Universal Soil Loss Equation (RUSLE) integrated with GIS has been used to estimate soil loss in the part of coastal Odisha system. The study area, Ganjam block have undulating topography covering 0-35% slopes. The quantitative soil loss was estimated and classified into different classes and soil erosion map was generated. The soil erosion map is classified into seven classes from very slight (80 t ha-1 yr-1). The results indicate that 90.9% (22330 ha) of the study area falls in very low erosion category, which may be due to level topography and regular vegetation cover. The other erosion classes such as moderate, high and very high erosion occurred in the range of 2.12%, 2.23% and 1.49 %, respectively. The high soil erosion risk is spatially situated in the foothills and upper steep slope of the area. The results can certainly aid in implementation of soil management and conservation practices to reduce the soil erosion in the coastal Odisha regions of Eastern India.

Tomato is an important vegetable crop and plays a major role in the food and nutrition security of the people of Mali. Production has increased in the recent decades but improvement in the fruit yield and quality remains suboptimal. Limited access to the best-adapted tomato varieties to the local conditions, pests and diseases are the major limiting factors for improving productivity. This study evaluated the performance of different tomato entries and varieties for their productivity, resistance to pests and diseases and postharvest fruit quality in Mali. Twenty-two entries and varieties of tomato in the rainy season and twenty-four in the dry season were evaluated. Varieties that were well adapted, better yielded, disease resistant and with good fruit quality were identified. Major plant diseases observed included tomato yellow leaf curve disease (TYLCD), bacterial wilt, bacterial leaf spot, early blight and southern blight. However, TYLCD was the major problem during the dry season. The variety of Icrixina was the most affected by TYLCD in both the rainy and dry seasons, although its total yield was not affected and remained one of the highest. Konica was one of the most susceptible varieties to bacterial wilt and bacterial leaf spot diseases. Tomato accession AVTO1710 provided the highest fruit yield (40.9 t/ha), while AVTO1704 provided the lowest (6.50 t/ha) in the rainy season. In contrast the highest yield during the dry growing season was 20 t/ha from VIO43614. Tomato entries and varieties varied in their postharvest fruit quality attributes (firmness, total soluble solid, pH and dry matter). Production season clearly influenced yield, disease occurrence and severity, as well as postharvest fruit qualities. The study identified better disease-resistant and yielding tomato entries suitable for rainy and dry growing seasons, which can be considered and scaled up for production so that farmers in Mali can produce tomato all year round.

Bacterial wilt, caused by Ralstonia solanacearum, is an emerging constraint in amaranth production in Benin. Host resistance is the most sustainable disease control measure. Ten amaranth varieties including A2002, Bresil (B) -Sel, Madiira 2, AC-NL, GARE ES13-7, Madiira 1, UG-AMES13-2, AM-NKGN, IP-5-Sel and a local variety from Benin were screened for resistance to bacterial wilt. The study was conducted in a screen house and in the naturally contaminated open field during a consecutive rainy and dry season using a randomized complete block design with four and three replications, respectively. In the screen house, plants were inoculated by drenching a 40 mL of bacterial suspension containing 108 CFU/mL of R. solanacearum strain NCBI 5 GenBank N° MH397250 at the collar region. The bacterial wilt incidence (BWI) and the area under the disease progress curve (AUDPC) suggested differential reactions of amaranth varieties to the pathogen. BWI and AUDPC were low for UG-AMES13-2, moderate for Madiira 2, AM-NKGN and the local variety and very high for A2002, Bresil (B) -Sel, AC-NL, GARE ES13-7, Madiira 1 and IP-5-Sel. The World Vegetable Center’s UG-AMES13-2 can be considered as first choice, which is resistant to R. solanacearum, and should be scaled up for seed production towards supporting farmers.

The South American tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), one of the most important invasive insect pests affecting tomato production worldwide, was for the first time detected in Myanmar. Preliminary surveys on pest occurrence on tomato crops in Myanmar suggested the presence of T. absoluta in Southern Shan State, but there was no official survey conducted until the end of 2019. Therefore, this study aimed to confirm the presence of T. absoluta in Myanmar. The presence of T. absoluta was specifically observed in the Southern Shan State, which is the largest tomato production area in Myanmar, where tomato is grown under two cultivation methods, floating and land cultivation. The highest T. absoluta infestation was recordedat Kalaw with (82%), followed by Inle Lake (i.e., floating cultivation) (20%) and Pin Ta Ya (10%). The amount of T. absoluta larvae was significantly higher in the lower third of the plants, followed by the middle section and upper section, respectively, in three fields surveyed. Potential and severe economic damage may be expected if management practices are not in place to reduce the presence of this invasive pest. It is of immediate importance that plant protection and quarantine offices of ASEAN member states coordinate their response to T. absoluta and build their capacity to monitor the pest and develop a strategy for when it arrives. In addition, a suitable management strategy is needed to reduce the occurrence of this invasive pest.

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most economically important pests of tomato worldwide. Despite its global importance, the management of this oligophagous pest has still been a challenging task, due to its high capability to develop resistance against synthetic insecticides. Given the limited studies on the effectiveness of different bio-pesticides in India, the objective of this research was to determine the pathogenicity of different commercial formulations of Beauveria bassiana, Bacillus thuringiensis, and neem (Azadirachtin), against T. absoluta, under laboratory and field conditions. For the Bacillus thuringiensis formulations, Green Larvicide® and Delfin® recorded an LC50 of 4.10 × 10⁹ CFU/mL and 8.06 × 106 spores/mg, respectively, while for the B. bassiana formulations, Green Beauveria® and BB Power® were 4.473 × 107 spores/mL and 1.367 × 107 CFU/g, respectively. Furthermore, the results showed high susceptibility to both the commercial neem formulations with Ecotin®, recording an LC50 of 91.866 ppm, and Econeem Plus® recording 212.676 ppm. The results from the field conditions at different locations of Andhra Pradesh, India, showed significant differences (p < 0.001) for leaf and fruit infestation among the interaction effect of treatments and locations. Bio-pesticides, especially neem and B. thuringiensis formulations, reduced T. absoluta infestation similarly to the chemical treatment, without affecting the yield. Therefore, bio-pesticides can be considered as safe alternatives to synthetic pesticides, for the management of T. absoluta.

Meteorus pulchricornis (Ichneumonoidea, Braconidae) is an endoparasitoid wasp of lepidopteran caterpillars. Its parasitic success relies on vesicles (named M. pulchricornis Virus-Like Particles or MpVLPs) that are synthesized in the venom gland and injected into the parasitoid host along with the venom during oviposition. In order to define the content and understand the biogenesis of these atypical vesicles, we performed a transcriptome analysis of the venom gland and a proteomic analysis of the venom and purified MpVLPs. About half of the MpVLPs and soluble venom proteins identified were unknown and no similarity with any known viral sequence was found. However, MpVLPs contained a large number of proteins labelled as metalloproteinases while the most abundant protein family in the soluble venom was that of proteins containing the Domain of Unknown Function DUF-4803. The high number of these proteins identified suggests that a large expansion of these two protein families occurred in M. pulchricornis. Therefore, although the exact mechanism of MpVLPs formation remains to be elucidated, these vesicles appear to be “metalloproteinase bombs” that may have several physiological roles in the host including modifying the functions of its immune cells. The role of DUF4803 proteins, also present in the venom of other braconids, remains to be clarified.

Solanum viarum has been proposed as a potential dead-end trap crop for the management of Helicoverpa armigera because of its unsuitability for larval growth and survival despite being overwhelmingly preferred for oviposition. This study delved into the different S. viarum accessions for ovipositional preference and non-suitability for larval growth and survival of H. armigera. Besides, foliage trichomes, acylsugars, and phenolic content of S. viarum plants were assessed and compared with tomato. Since there is no significant variation in the ovipositional preference and larval performance of H. armigera, our result revealed that all those evaluated accessions of S. viarum have the potential to be used as a dead-end trap crop for the management of H. armigera. However, significant variation among the S. viarum accessions in terms of H. armigera oviposition was also evident in a no-choice experiment. Because of high-density glandular trichomes, acylsugars, and phenolic content, S. viarum significantly impaired H. armigera larval growth and survival compared to the tomato. Hence, our study elucidated that the S. viarum plant fits with the criteria for dead-end trap crop, and has the potential as a dead-end trap crop for the H. armigera, which needs to be tested under large, open-field conditions.

Bacterial wilt (BW) is one of the most economically important diseases of tomato and eggplant in the tropics and subtropics, and grafting onto resistant rootstocks can provide an alternative and effective solution to manage soil-borne bacterial in these crops. This study was conducted to evaluate the BW resistance and agronomic potential of newly identified eggplant accessions as rootstocks for tomato grafting. Five BW resistant eggplant accessions (VI041809A, VI041943, VI041945, VI041979A, and VI041984) from the World Vegetable Center were evaluated as rootstocks for grafting with two different fresh market tomato cultivars (Victoria and TStarE) as scion under open field conditions in Taiwan. Graft compatibility using the tube grafting method as well as BW wilting percentage, disease index, fruit yield and quality parameters were assessed. All the rootstocks showed good graft compatibility (93% and above) and grafted plants showed low wilting percentage (0.0–20.0%) and disease index (0.0–20.8%) following inoculation with BW. Yield for the eggplant rootstock grafted tomato plants was higher compared to the non-grafted tomatoes and self-grafted tomato. Fruit quality was not affected by grafting, although some differences in antioxidant activities were observed. The new eggplant rootstocks can be considered as alternatives to the rootstocks currently used for commercial production of tomatoes during the hot-wet season.