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The phyllosphere hosts a considerable number of microorganisms, providing a vast habitat for naturally associated phyllobacteria due to its topography as it offers various colonization and infiltration sites. Contamination of vegetables may occur through pre-harvest and post-harvest activities and include cross-contamination from infected personnel. The study aimed to examine the prevalence of microbial contamination for spinach (Spinacia oleracea L.) and cabbage (Brassica oleracea var. capitata L.) at various farms based on the production and agronomic systems in South Africa, Free State. In addition, the study further demonstrated that several potentially pathogenic microorganisms are present in common fresh leafy greens such as spinach and cabbage. Almost all the analyzed and identified microorganisms were reported to be opportunistic pathogens. Spinach and cabbage phyllosphere were contaminated mostly with Staphylococcaceae, Pseudomonadaceae, Morganellaceae, Caulobacteraceae, Moraxellaceae, Burkholderiaceae, Yersiniaceae, Xanthomonadaceae, Listeriaceae and total coliform species. The predominant genera were Staphylococcaceae, Morganellaceae and Pseudomonadaceae in spinach and cabbage isolates. The analysed isolates revealed a high level of contamination by opportunistic pathogens such as total coliform, Morganellaceae and Staphylococcaceae reflecting a deficit of good agricultural production systems and hygiene practice. From the study, the authors could also demonstrate the rapid rate at which these pathogens can spread through the food chain and cause food poisoning. It is concluded that the bacterial contamination frequency and degree in this present study was significantly considerable and recommended that these vegetables be thoroughly washed before any consumption especially when consumed uncooked, specifically in green salad. Moreover, preparing cooked meals using these leafy vegetables would be better. [ABSTRACT FROM AUTHOR]

• Amaranthus cabbage, Bidens dumpling, and fish pea (cowpeas) dishes were developed. • Sensory evaluation suggest that all three dishes were acceptable and liked by children. • The three dishes were accepted for attributes of colour, taste, and smell. • Amaranthus cabbage was the most highly acceptable. • The findings emphasizes the importance of culinary services. • Innovation and diffusion of indigenous food recipes is still in a development phase. The study aimed to develop innovative vegetable dishes using three indigenous crops to enhance consumption by children. A quantitative approach using traditional preservation, experimental and laboratory-based methodologies for development of recipes and the nutrient analysis was used. This involved developing the dishes Amaranthus cabbage, Bidens dumpling, and Fishpea. Nutrient analysis was done at the Aspirata food and nutrient analysis laboratory in Cape town. Sensory evaluation results suggest that all three dishes were acceptable and liked by children for all three attributes of colour, taste, and smell, with Amaranthus cabbage as the most highly acceptable. The results on the palatability of the three dishes using open-ended questions affirm that more children had positive comments on the dishes – which concurs with the quantitative data. The findings emphasize the importance of culinary services where innovation, imitation, and diffusion are still in a development phase especially for indigenous foods. [ABSTRACT FROM AUTHOR]

The diamondback moth (Plutella xylostella L.) is the most destructive insect pest on cabbage (Brassica oleracea var. capitata L.). Infestation by this pest usually results in the indiscriminate use of insecticides by farmers due to a lack of sampling plans for this pest. Sampling plans for P. xylostella management decisions on winter–spring cabbage in the Eastern Cape Province of South Africa were developed, through population monitoring that comprised weekly counts of immature stages of P. xylostella on 60 plants for 11 wk each during the winter and spring seasons. The mean density–variance relationship was used to describe the distribution of the pest, and number of infested plants was used to develop a fixed-precision sampling plan. All plant growth stages preceding maturation were vulnerable to P. xylostella damage resulting in yield losses. A high aggregation of P. xylostella on cabbage was observed in spring than in winter. The average sample number to estimate P. xylostella density within a 15% standard error of the mean was 35 plants. Furthermore, the estimated plant proportion action threshold (AT) was 51% with density action thresholds of 0.50 and 0.80 for spring and winter, respectively. Fitting P. xylostella cumulative counts in the winter and spring sampling plans resulted in 100% and 45% reduction in insecticide treatments. The similarity of sample size and ATs between both seasons provides evidence that a single sampling plan is practical for all cabbage growing seasons. The similarity of the estimated ATs to those acceptable in established integrated pest management programs indicates reliability. [ABSTRACT FROM AUTHOR]

The hyper-eutrophic conditions in impoundments used for irrigation around South Africa’s major cities promote the co-existence of linear alkylbenzene sulfonate (LAS) and other pollutants such as metals. The combined effects of LAS and metals, when such water is used to irrigate crops, has not been properly investigated in light of human health risks and prevailing local conditions. To understand the potential risks, pot-culture experiments were conducted to assess the effect of the LAS, sodium-dodecyl-sulfonate (SDS), on the accumulation of aluminum (Al), manganese (Mn) and strontium (Sr) in Brassica oleracea (cabbage) and Solanum tuberosum (potato) plants. The plants were watered with dam water containing 3.48 mg·L−1 of the LAS (sodium dodecyl sulfonate) and Mn (0.257 mg·L−1), Al (0.6 mg·L−1) and Sr (0.16 mg·L−1) as determined by field surveys, for 20 days. The presence of SDS in the irrigation water at environmentally relevant concentrations did not enhance uptake of Sr, Mn, Al in the two plants, as demonstrated by statistically insignificant differences in the means of the treatments (with and without SDS). In addition, the presence of the metals, high pH, EC and presence of cyanotoxins in the water did not affect total chlorophyll and growth of the plants. These findings imply that the prevailing levels of anionic surfactants such as SDS, metals and other contaminants in the hyper-eutrophic reservoirs pose little risk to crop yields, quality of crops and human health, due to the possible accumulation of these contaminants in irrigated plants. Despite the study reporting no immediate inherent risk to the plants and human health, continuous monitoring of the contaminants in water, soil and irrigated plants is recommended since the conditions, concentrations and other factors can quickly change if the management of the catchment does not improve in the near future. [ABSTRACT FROM AUTHOR]

Annually, significant crop losses are reported due to diseases caused by phytopathogens. Most subsistence farmers cannot afford the high cost of chemical treatments thereby resulting in the increasing dependence on plant extracts to manage crop diseases. In this study, we documented plants used for the management of cabbage and spinach diseases in OR Tambo Municipality, Eastern Cape Province. An ethnobotanical survey using semi-structured questionnaires was used to document plants and plant parts used by the subsistence farmers in managing cabbage and spinach diseases. Semi-structured questionnaires were administered to 41 consenting subsistence farmers from November to December in 2021, using snowball sampling. The collected data were subjected to descriptive statistical and ethnobotanical analyses. A total of 17 plants belonging to 10 families were identified by the participants as being used in mitigating cabbage and spinach diseases. Tulbaghia violacea, Aloe ferox, and Capsicum annuum had the highest use value of 0.32 each, whereas Tulbaghia violacea had the highest relative frequency of citation of 0.39. This current study revealed the importance of plants in managing crop diseases in local communities. It provides baseline data for future pharmacological evaluations in authenticating the efficacies of the identified plants in managing crop diseases. [ABSTRACT FROM AUTHOR]

Enterobacter species are gram-negative, motile, non-spore-forming, rod-shaped, facultatively anaerobic bacteria of the Burkholderiaceae family. Burkholderia includes several species, which can be risky pathogenic bacteria to vegetables, including cabbage, and therefore have an impact on the fresh production of cabbage. This study was conducted to isolate and identify Burkholderia from a cabbage field in Limpopo Province, South Africa. Therefore, this molecular study was conducted in 2023 at Limpopo University to identify the bacterium associated with cabbage filed from South Africa's soils using 16S rDNA marker. The DNA was extracted using the Chelex method. The bacterium was identified as Burkholderia. The Nblast analysis showed that South African Burkholderia had 95% similarity with a population from South Africa (MG593873). Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as Burkholderia in the same clade with highly supported (100) bootstrap values. In conclusion, this species was identified using 16S rDNA properly. However, using other DNA markers for a better understanding of Burkholderia phylogeny is recommended. [ABSTRACT FROM AUTHOR]

Literature suggests that there are high levels of commercialisation by even the poorest and smallest landholders within the horticulture subsector in most rural Africa. Thus, the notion of poor commercialisation among smallholder farmers is now being challenged. Against this background, this paper estimated factors that influence commercialisation by smallholder cabbage farmers in the Eastern Cape Province of South Africa. The study used a cross-sectional survey of 120 smallholder cabbage farmers obtained through a multistage sampling procedure. A Cragg double-hurdle model was applied to analyse the factors that influence the commercialisation decision and intensity of commercialisation. In the first stage, the result of the probit regression model revealed that gender, age, access to informal credit and area planted were significant factors towards influencing smallholder cabbage farmers' commercialisation decisions. In the second stage, the results of the truncated regression model revealed that family size and area planted were the key factors determining the intensity of commercialisation. Hence, the attempts to improve smallholder farmers' cabbage commercialisation should be guided by these significant explanatory variables in the study area, given the low commercialisation index revealed. [ABSTRACT FROM AUTHOR]

This study evaluated the level of selected pesticide residues in the staple vegetables; Brassica oleraceavar. capitata (cabbage), Betavulgarisvar. cicla (Swiss chard), and Solanum tuberosum (potato) from fresh produce markets in the city of Bloemfontein, South Africa. A QuEChERS extraction method was used followed by quantitation using GC‐HRT/MS. The pesticide residues were detected in levels lower than the recommended Maximum Residue Levels ranging from not detected to 121.6 ng/kg recorded for heptachlor in cabbage samples. Cabbage was generally susceptible to pesticide residue accumulation with the average total concentration for different markets at 222 mg/kg. The pesticide residues were predicted to be from recent applications but their existence within guideline limits indicated that their use in vegetable farming was within the FAO/WHO recommended good agricultural practices. While the current situation points that consumption of the vegetables in the province poses limited health concerns due to organochlorine pesticides, the unmonitored use of products containing these compounds may result in elevated levels. Continued monitoring and a call for the South African legislature to revise its regulations of the Fertilizers Act to reflect the current international laws on pesticides management is recommended. [ABSTRACT FROM AUTHOR]

Heterodera schachtii (Tylenchida: Heteroderidae), also called the sugar beet cyst nematode, are of economic importance worldwide. Oilseed rape (Brassica napus L.), which is a crop of global importance, suffers yield loss when it is infected with H. schachtii. The first report of the occurrence of H. schachtii in South Africa was made in 1968 on the Greater Cape Flats of the Western Cape province of South Africa, showing the widespread occurrence and the high nematode numbers on cabbage, cauliflower, beetroot and Brussels sprouts. The penetration, development and life cycle of a local H. schachtii population on seven vegetables (beetroot, broccoli, Brussels sprout, cabbage, cauliflower, lettuce and turnip) and three weeds (black nightshade, purslane and shepherd's purse) commonly grown, or found, in the Greater Cape Flats region of the Western Cape, South Africa, and two candidate trap crops (white mustard and oilseed radish) were examined under laboratory conditions. All the vegetables and weeds were found to be good hosts of H. schachtii, with the exception of lettuce, which was found to be a non-host. Oilseed radish and white mustard allowed penetration and some nematode development, but no, or little, cyst formation. Female bodies filled with eggs were observed from 31 to 34 days after inoculation onwards on all the vegetables and weeds, except for on beetroot, on which female bodies filled with eggs were observed a few days later. The results from this study are important, especially in terms of the adaptation of vegetable crop rotation cycles that are practised on the Cape Flats, so as to prevent the build-up of H. schachtii populations in agricultural settings. [ABSTRACT FROM AUTHOR]

This paper investigates the water use and marketing behaviour of smallholder cabbage producers from the Zanyokwe Irrigation Scheme in South Africa to identify the behaviour associated with the highest financial returns to water allocated to smallholder farmers to decrease rural poverty. The blue water footprint for cabbages was estimated; the value of the water was then calculated as the gross margin and value added per cubic metre of water at the respective stages along the value chain. The analyses show that the attributes of the products have a major influence on the degree of access to the highest value market alternatives, and hence on the ability of smallholder farmers to generate the highest possible return from the water they receive for agricultural purposes. [ABSTRACT FROM AUTHOR]

Ecological sanitation is a system that, unlike the traditional waterborne sewerage and pit toilet systems, regards human excreta as a resource to be recycled rather than as a waste. There is, however, little or no information on the fertiliser value of human excreta in South Africa. This study, therefore, evaluated the effectiveness of human manure as a source of nutrients using cabbage as a test crop at Ntselamanzi location, Alice, South Africa as part of a project intended to generate knowledge and good practice in ecological sanitation. Treatments were arranged in a randomised complete block design with 4 replications and consisted of a control, 100 kg N·ha-1 as goat manure, and 4 non-zero rates of human manure and NPK fertiliser applied to supply the equivalent of 50, 100, 200, and 400 kg N·ha-1. Human manure resulted in higher cabbage yields than goat manure but was out-yielded by inorganic fertiliser. The greater effectiveness of human manure when compared with goat manure was attributed to the fact that it was a better source of K and P for plants as it maintained higher levels of these nutrients in soil than goat manure. For greater agronomic effectiveness, the human manure should be co-applied with some inorganic N fertiliser as it proved to be a poor source of nitrogen. The human manure increased soil pH and therefore has potential for improving crop growth in acidic soils through its liming effects as well. The dry human manure was evaluated as comparable to Type B sludge in South Africa with respect to microbial content and could therefore be used to fertilise some crops/plants provided stipulated restrictions to minimise human exposure are adhered to. [ABSTRACT FROM AUTHOR]

A 45m long, 4m wide and 1m deep wetland was constructed at Goudini in 2002 to treat distillery and winery effluent. After the plants were fully established, the wastewater with an average chemical oxygen demand (COD) of 14,000 mg/l was introduced to the wetland system at a rate of 4,050 litres per day. After treatment, wastewater at the outlet had an average COD of 500 mg/l, indicating more than 90% COD removal. After treatment, the wastewater was used to irrigate cash crops as part of poverty alleviation for farm workers. The experiment consisted of four treatment: clean irrigation water with fertilizer applied (B1); clean irrigation water without fertilizer applied (B2); wastewater irrigation with fertilizer applied (B3); and wastewater irrigation without fertilizer applied (B4). These were replicated seven times. Cabbage was cultivated as a cash crop. The results indicated that cabbage could be irrigated with winery wastewater treated by wetlands. The study found that there was significant difference between treatments that were fertilized compared with those that were not fertilized. The results indicated that wastewater irrigation improved the nutritional status of the soil. [ABSTRACT FROM AUTHOR]

The presence of large colonies of aphids is associated with a devastating novel necrotic disease of cabbage (Brassica oleracea var. capitata) in Ghana that is thought to be of viral etiology. In this study, we used molecular taxonomic tools to identify the aphid species present on these diseased cabbage plants. This was confirmed using two key features for morphological identification, involving the length of cornicles and shape of cauda for the wingless forms of the aphids. Two species of aphids were identified and their distribution in Ghana indicated. One was the generalist aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) but the most abundant was the brassica specialist aphid, Lipaphis erysimi pseudobrassicae (Davis) (Hemiptera: Aphididae), which is one of the most destructive pests of brassica crops in some countries in Africa and other parts of the world. L. erysimi has been reported in Benin, Mali, South Africa, India, China, and United States, but this is the first formal report of L. erysimi pseudobrassicae in Ghana. The correct identification of L. erysimi is crucial, suggesting that it has recently become one of the most common species of aphid found on cabbage plants in Ghana., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

A root rot of cabbage is reported from South Africa. The causal pathogen was identified as Phytophthora drechsleri, based on morphological characters and electrophoretic patterns of soluble proteins. [ABSTRACT FROM AUTHOR]

Knowledge of the microbiological quality and prevalence of antibiotic resistance and virulence genes in bacterial isolates from leafy green vegetables supplied by formal suppliers (retailers) and informal suppliers (street vendors) in South Africa is limited. Because leafy vegetables have been implicated in foodborne disease outbreaks worldwide, 180 cabbage and spinach samples were collected from three major retailers and nine street vendors in Johannesburg, South Africa. Escherichia coli and coliforms were enumerated using Petrifilm plates. The prevalence of Listeria monocytogenes, Salmonella, and Shigella was determined using real-time PCR analysis. Identities of presumptive E. coli isolates from the fresh produce were confirmed using matrix-assisted laser desorption-ionization time of flight mass spectroscopy. Isolates were characterized using phenotypic (antibiotic resistance) and genotypic (phylogenetic and virulence gene) analysis. Hygiene indicator bacteria levels on spinach from formal and informal retailers exceeded the maximum level specified by the Department of Health guidelines for fresh fruit and vegetables. E. coli counts for street vendor spinach were higher (P < 0.0789) than those for retailer spinach. E. coli was present in only two cabbage samples, at 0.0035 CFU/g. L. monocytogenes and Salmonella were detected in 7.2 and 5% of the 180 samples, respectively, based on real-time PCR analysis; Shigella was not detected. Of the 29 spinach E. coli isolates, 37.9% were multidrug resistant. Virulence genes eae and stx 1 were present in 14 and 3% of the spinach E. coli isolates, respectively; the stx 2 gene was not detected. Eighty-six percent of these isolates belonged to phylogroup A, 3% belonged to group C, 7% belonged to group E, and 3% belonged to clade 1. The results from the current exploratory study on the microbiological quality of spinach bought from selected retailers highlight the need for continued surveillance on a larger scale, especially in the informal sector, to characterize the potential health risks to the consumer.