Francis Bayo Lewu

Vegetable producers struggle with soil fertility challenges and ever-increasing inorganic fertiliser prices. Solid winery waste compost provides a promising solution to these problems and mitigates the environmental consequences of discarded winery waste. The use of organic soil amendments improves crop growth and yield; however, there is limited information on the responses of Swiss chard (Beta vulgaris var. cicla) to solid winery waste compost. This study assessed the effect of NPK fertiliser and two rates of solid winery waste compost on Swiss chard growth and yield. The experiment was conducted at the Agricultural Research Council, Bien Donné Farm, Paarl, South Africa, from April to June and was laid out in a randomised complete block design with four treatments: control, NPK fertiliser, and two solid winery waste compost rates. All plant growth parameters, the number of leaves, leaf length, and leaf width improved significantly with the solid winery waste compost treatments compared to the control. This was linked to the compost’s ability to act as a sponge, retaining water and slowly releasing nutrients throughout the growth cycle. The fresh yield of Swiss chard did not show a statistically significant difference (p>0.05) among the amended treatments. The lower compost rate resulted in a slightly larger, but not significantly different, yield (12.95 t/ha) compared to the high compost rate (11.78 t/ha) and NPK treatment (11.39 t/ha). This was attributed to a potential optimal application rate at the lower compost rate, in which conditions were optimal for nutrient absorption and soil pH. The high compost rate may have resulted in an antagonistic relationship with nutrients due to its higher pH and sodium content, leading to osmotic stress. These findings suggest that although solid winery waste compost is an effective soil amendment for improving Swiss chard growth, further research is needed to determine the optimal application rate necessary for significant yield improvement.

Indiscriminate use of chemical fertilizers has profound environmental implications that organic fertility options can circumvent. Lower macronutrient contents that warrant higher tonnage application rates hinders achieving higher relative agronomic efficiencies (RAE) in these organic fertilizers. The effects of short-term usage of organic fertilizers on selected soil and plant parameters and the potential of harnessing biochar’s unique characteristics to improve RAE of other organic fertilizers at reduced application rates were evaluated. The seven-year (2015 to 2021) field trial composed of two near raw organic fertilizers: Gliricidia sepium leaves (GL) and poultry manure (PM) and two composted organic materials: sole compost (SC) and bone meal fortified SC termed phosphocompost (PC). There were also two control treatments: chemical fertilizer (sole CF) and absolute control (AC). Each organic fertilizer was applied at 5 t ha-1 during 2015 to 2019 cropping seasons. In 2021, biochar was coapplied at 0.5 t ha-1 with the other organic fertilizer at a reduced rate of 2.5 t ha-1. Data taken on soil organic carbon (SOC), available P, dry grain (DGY) shoot weights (DSW), and grain N and P contents at the end of the 2015, 2019, and 2021 cropping seasons were subjected to analysis of variance. Treatment means of the selected years were compared using Chi-square at P

Soil degradation and water scarcity are major challenges affecting crop productivity in sandy soils. Zeolite, a naturally occurring aluminosilicate mineral, has been explored as a soil amendment to improve soil properties and enhance plant growth for various crops. However, limited information on the influence of zeolite soil amendment on Swiss chard nutritional content. A greenhouse pot experiment was conducted at the Agricultural Research Council, Infruitec-Nietvoorbij, Stellenbosch, South Africa from late autumn to late spring. The study accessed the effects of zeolite soil amendment on dry matter yield, moisture content, crude ash, and crude protein of Swiss Chard (Beta vulgaris var. cicla cv. Ford Hook Giant) over five harvests. The experiment was laid out in a completely randomised block design with four treatments 0; 10; 20 and 30% zeolite application to sandy soil, all at 12 kg sandy soil or sandy soil and zeolite mixture. Data were analysed using analysis of variance (ANOVA), and treatment means were compared using Fisher’s least significant difference test at a 5% probability level. The results of this study show that zeolite through its porous nature, high cation exchange capacity and alkalinity may be used to improve water availability to plants (moisture content) while at the same time improving dry matter yields and mineral accumulation (crude ash content). However, zeolite did not improve the crude protein contents of Swiss chard, which is a function of nitrogen assimilation. Nevertheless, 20–30% zeolite application levels can be used as an effective method to combat soil degradation and mitigate drought-related challenges. These rates improved dry matter yields, enhanced crop moisture content, and promoted crude ash and/or mineral accumulation in Swiss chard.

Background: Global blueberry production has proliferated in recent years, driven by the increasing consumer awareness of its nutritional benefits. Blueberry is considered a rich source of antioxidants, believed to contribute to several health benefits, including maintaining heart health and protecting against cellular damage. Aim: This review critically evaluated the existing literature on blueberry cultivation using different nitrogen sources and identified research gaps needing further investigation. Setting: This review provides an overview of blueberry cultivation under different nitrogen sources. Methods: A literature search for existing information on blueberry cultivation under different nitrogen sources was conducted using online databases via the Cape Peninsula University of Technology (CPUT) library website database. Results: Findings suggest that nitrogen sources significantly affect the productivity of blueberries, with ammonium producing better results than nitrate. There is a noticeable gap in the literature on how different nitrogen sources influence the biosynthesis of secondary metabolites in blueberries. Conclusion: The review revealed that there are few research studies on blueberry cultivation under different nitrogen sources. Given the nutritional and antioxidant significance of blueberry secondary metabolites, further research is critical. Contribution: Information gained can aid in understanding different nitrogen sources of nutrition in blueberries. Insights from this research can inform nitrogen management strategies in blueberry cultivation. This is important for sustaining production trends and ensuring the economic viability of the industry.

A zeolite pot experiment was conducted at the Agricultural Research Council Infruitec-Nietvoorbij in Stellenbosch, South Africa, under greenhouse conditions. The experiment aimed to investigate the impact of zeolite application on soil enzyme activities in sandy soils cultivated with Swiss chard (Beta vulgaris Var. cicla) and cabbage (Brassica oleracea Var. capitata L.) over two years (2018-2019). Different zeolite-to-soil ratios (0:1, 1:9, 2:8, and 3:7 w/w) were used, with each pot containing 12 kg of soil. The experiment involved 72 pots for each vegetable, arranged in a randomized complete block design (RCBD). Soil enzyme activities, including acid phosphatase, β-glucosidase, and urease, as well as soil chemical properties (pH, total plant-available nitrogen, organic carbon, and phosphorus), were analyzed. Key findings indicate that the effect of zeolite application on enzyme activities varied between the vegetable species. Zeolite application significantly increased (P

Background: Pelargonium sidoides (P. sidoides) DC. (Geraniaceae) is one of several geophytic species of the genus that are important traditional medicines in South Africa. P. sidoides has been identified as a potential future economic species known to cure various ailments, including respiratory infections. Aim: This review was aimed at addressing concerns around the overexploitation of P. sidoides in the wild. Setting: This review provides an overview of P. sidoides cultivation and usage. Method: A comprehensive literature search involving mainly electronic and library sources of information was used to collate and synthesise published data. Results: According to the findings of the study, there has been a huge increase in demand for the plant and it has been overexploited locally as a result of increased domestic and global demand from native consumers and the pharmaceutical industries. Conclusion: The review emphasises the necessity of cultivation in ensuring the sustainability of P. sidoides in the wild. Cultivation is a crucial component of conservation attempts which is under threat because of increasing urbanisation, habitat degradation, and population growth. Furthermore, producing medicinal plants allows new rural farmers to produce them as a new crop option, reducing unsustainable wild collection and competition with established commercial farmers who mostly raise food crops. Lastly, the study reveals the benefits in cultivating medicinal plants namely the strengthening of primary healthcare through traditional medicine, the preservation of indigenous knowledge, local economic growth, and job creation. Contribution: The benefits of cultivation and using P. sidoides medicinally are reviewed in this essay.

Honeybush (Cyclopia spp.) is a rich source of antioxidant properties and phenolic compounds. Water availability plays a crucial role in plant metabolic processes, and it contributes to overall quality. Thus, this study aimed to investigate changes in molecular functions, cellular components, and biological processes of Cyclopia subternata exposed to different water stress conditions, which include well-watered (as Control, T1), semi-water stressed (T2), and water-deprived (T3) potted plants. Samples were also collected from a well-watered commercial farm first cultivated in 2013 (T13) and then cultivated in 2017 (T17) and 2019 (T19). Differentially expressed proteins extracted from C. subternata leaves were identified using LC-MS/MS spectrometry. A total of 11 differentially expressed proteins (DEPs) were identified using Fisher’s exact test (p < 0.00100). Only α-glucan phosphorylase was found to be statistically common between T17 and T19 (p < 0.00100). Notably, α-glucan phosphorylase was upregulated in the older vegetation (T17) and downregulated in T19 by 1.41-fold. This result suggests that α-glucan phosphorylase was needed in T17 to support the metabolic pathway. In T19, five DEPs were upregulated, while the other six were downregulated. Based on gene ontology, the DEPs in the stressed plant were associated with cellular and metabolic processes, response to stimulus, binding, catalytic activity, and cellular anatomical entity. Differentially expressed proteins were clustered based on the Kyoto Encyclopedia of Genes and Genomes (KEGG), and sequences were linked to metabolic pathways via enzyme code and KEGG ortholog. Most proteins were involved in photosynthesis, phenylpropanoid biosynthesis, thiamine, and purine metabolism. This study revealed the presence of trans-cinnamate 4-monooxygenase, an intermediate for the biosynthesis of a large number of substances, such as phenylpropanoids and flavonoids.

Heavy metals are unbreakable, and most of them are poisonous to animals and people. Metals are particularly concerning among environmental contaminants since they are less apparent, have extensive effects on ecosystems, are poisonous, and bioaccumulate in ecosystems, biological tissues, and organs. Therefore, there is a need to use biological agents and phytoremediation processes such as enzymes because they have a high potential for effectively transforming and detoxifying polluting substances. They can convert pollutants at a detectable rate and are potentially suitable for restoring polluted environments. We investigated heavy metal concentrations in different soil samples collected in four sections in Alice and determined the enzyme activity levels present in the soil. The Pearson correlation analysis was conducted to check whether there was any relationship between heavy metal concentrations and enzyme activities in the soil. Samples were randomly collected in three weeks, and the microwave digestion method was used for sample treatment and preparation. Quantitation was achieved by inductively coupled plasma mass spectrometry (ICP-MS). The enzyme assay through incubation method was implemented for discovering the four selected enzymes (urease, invertase, catalase, and phosphatase), and their activity levels were examined colorimetrically by colorimetry spectrophotometer. The ICP-MS results revealed 16 predominating elements, namely: Al, Ba, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Sr, and Zn, and the presence of a non-mental, which is phosphorus (P), and a metalloid in the form of silicon (Si) in all soil samples. Significant differences in metal concentrations were observed among the collection sites. The Al, Fe, K, Mg, and Ca concentrations were above WHO’s permissible limits. While Ba, Mn, Na, and P were in moderate concentration, Cu, Cr, Co, Zn, Sr, and Ni were in small amounts recorded mostly below the permissible values from WHO. Four soil enzyme activities were determined successfully (urease, invertase, phosphatase, and catalase). A negative non-significant correlation existed between urease, invertase, phosphatase enzyme activity, and the concentration levels of all selected metals (Al, Ba, Ca, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Cr, Sr, and Zn. In contrast, the content of catalase activity was associated non-significantly but positively with the range of selected heavy metals. This study suggests proper monitoring of residences’ areas, which can provide detailed information on the impact of high heavy metal content on people’s health. They are easily dispersed and can accumulate in large quantities in the soil. The necessary implementation of waste management programs will help the municipality adopt a strategy that will promote recycling programs and protect the residence health from this threat.

A survey of rural turkey farmers was conducted in three villages in the Eastern part of Nigeria, namely: Amukwa, Amaeze and Nguru. The aim of the study was to assess the prevailing management and production practices of turkey farmers in the area. Information obtained included flock size, reasons for keeping birds, breeding and management practices among others. The multi-stage random sampling method was used to collect information from 180 respondents. Results obtained revealed variability in response among flock sizes (1–20), with most (90%) respondents being part-time farmers. Mean scores, in terms of the level of adoption of standard management practices by turkey farmers, were given as cleaning and disinfection of pen before restocking ( x= 4.60), removal of droppings (x = 4.57), and changing and replacement of litters ( x= 4.4). Beak trimming ( x= 1.27) was the lowest-ranked farm practice by farmers. It was concluded that the management practices and production of turkey in the study area are below standard when compared to those in developed societies. Adequate support for farmers in terms of finance and regular training, among others, by relevant agencies including the government may help improve the production of turkey in the area.