S.Z. Tesfay's research while affiliated with University of KwaZulu-Natal and other places

Publications (63)

Article
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The study aimed to investigate the effect of enriching Aloe vera and Moringa oleifera plant extract edible coatings with chitosan nanoparticles on the postharvest quality of 'Cavendish' bananas. Banana fruits were dipped into the following treatments: Aloe vera 50% (AV), Moringa oleifera 10% (MO), Aloe vera 50% + chitosan nanoparticle 2% (AV+CN), a...
Article
Trellising is one of the most important horticultural practices used during the growth and development of tomatoes produced in tunnels and open fields. The effect of different trellising methods was investigated on leaf gaseous exchange and photosynthetic efficiency of fertigated indeterminate tomatoes (Solanum lycopersicum) grown in a dome-shaped...
Article
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The lower yield of tomatoes grown in tunnels, due to the limited space, remains a challenge. Stem training has long been identified as one of the most important horticultural practices used to improve the yield and fruit quality of tomatoes grown in commercial tunnels; however, there is little information available on the dome-shaped tunnels that a...
Article
Full-text available
Abstract Climacteric fruits continue to ripen after harvest and produce ethylene, coupled with an increase in respiration rate, which contributes to more rapid perishability. Inhibition of ethylene biosynthesis has been shown to be an efficient way to delay the onset of ripening and lengthen shelf life. The use of edible materials as coatings prese...
Article
Adulteration monitoring of processed powdered horticultural products is an important aspect of research in order to facilitate fair trade, ensure food authenticity and safety in the agricultural food industries. Globally, a diversity of horticultural powdered products prone to adulteration include herbs and spices; fruit and vegetable flours; hot b...
Article
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Biostimulant application during the cultivation of underutilized crops is an environmental-friendly approach for their production and utilization to promote food security and human health. This study investigated the effect of two commercial biostimulants (a seaweed-based extract, Kelpak® (1:100, 1:40, and 1:20, dilutions), and plant growth promoti...
Article
Kiwifruit (Actinidia chinensis) exhibits little to no visible evidence of physical quality attributes considered as perfect indicators of fruit developmental stage of which maturity can be measured. Maturity indexing is a perfect tool that is used in determining the optimum picking time and its effect on kiwifruit quality during postharvest storage...
Article
The study was conducted to investigate the effects of cold storage temperatures on the quality of kiwifruit harvested over different maturity stages. Two golden kiwifruit cultivars (‘Y368’ and ‘Soreli’) were harvested from Richmond (KwaZulu Natal, South Africa). The fruits were separated into early, mid, and late harvested kiwifruits. Fruits were s...
Article
The study was conducted to investigate the effects of cold storage temperatures on the quality of kiwifruit harvested over different maturity stages. Two golden kiwifruit cultivars (‘Y368’ and ‘Soreli’) were harvested from Richmond (KwaZulu Natal, South Africa). The fruits were separated into early, mid, and late harvested kiwifruits. Fruits were s...
Article
The short shelf-life of bananas at ambient temperature is a serious problem since the temperature accelerates ripening-related processes like tissue softening, senescence, and fungal diseases. The study aimed to investigate the effect of enriching aloe vera and moringa plant extract edible coatings with chitosan nanoparticles on the postharvest qua...
Article
Full-text available
This study evaluated the effect of edible coating and gaseous ozone on the antioxidant activities and biochemical properties of mango fruit. Mango fruit (cv. Keitt) were coated with moringa leaf extract and carboxymethyl cellulose (EC) before exposure to ozone (0.25 ppm). Gaseous ozone (O3) was administered intermittently for 24 or 36 h, and the co...
Article
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Seed germination is a crucial step in plant propagation, as it controls seedling production, stand establishment and ultimately crop yield. Approaches that can promote seed germination of valuable crops remain of great interest globally. The current study evaluated the effect of biostimulant (Kelpak® and plant-growth-promoting rhizobacteria-PGPR) b...
Article
The demand for gluten-free banana flour has led manufactures to enforce strict measures for quality control. A need has arisen for the development of more sensitive and reliable methods to test the quality of green banana flour (GBF). The objective of this study was to develop rapid visible to near-infrared (Vis-NIR) based spectroscopic models to d...
Article
This study investigated the effect of nine different wheat adulteration levels (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% and 90% added wheat) on the concentration of resistant starch (RS) of green banana flour (GBF). The study further evaluated the potential application of visible to near infrared (Vis-NIR) spectroscopy with multivariate analysis to...
Article
Full-text available
Mango is the third most important fruit in the tropics due to its nutritional properties and delicious flavor. The fruit is exceptionally perishable due to its climacteric nature, which decreases the quality and shelf-life. Preserving fruit quality and preventing losses during postharvest is one of the critical solutions in sustaining human dietary...
Article
Organic coatings are in high demand for substituting the waxes and chemical treatments usually applied for maintaining the postharvest quality of fresh fruit and vegetables. This study investigated the efficacy of organic coatings incorporated with moringa (Moringa olifera) leaf extracts (MLE) on maintaining the rind physiological quality of ‘Marsh...
Article
Raw and roasted kernels of ‘A4’ and ‘Beaumont’ macadamia cultivars were assessed for biochemical and sensory quality during the accelerated storage of 70 days. Kernels were roasted at 125 °C for 15 min using a hot air oven dryer. Roasted kernels had significantly (p < 0.001) high concentration of phenols, antioxidants and good sensory properties: a...
Chapter
Successful seed germination results in the production of the next generation of plants, and is a critical phase in their growth and survival. Germination involves different processes including imbibition, protein synthesis, and phytohormone production. All of these processes can be manipulated by extrinsic factors including the application of biost...
Article
Harvest maturity of avocado fruit is currently estimated based on dry matter content (DM). The DM is analyzed destructively from few samples representing the entire orchard. However, oil content (OC) is the only maturity parameter with a direct link to eating quality of avocados. Successful studies indicating non-destructive assessment of avocado O...
Article
This study evaluated the feasibility of using bio-markers to develop statistical models for predicting time to maturity of avocado fruit. The experiment used 'Mendez#1ʹ and 'Hass' as model cultivars. Fruit was sampled biweekly from two positions within the tree canopy, namely, inside and outside canopy. Nine fruits per canopy position were sampled...
Article
Ozone is a triatomic molecule of oxygen well-known as a powerful disinfectant because of its higher oxidation potential. Ozone has recently gained more interest especially from producers of organic fresh horticultural products. This happened after it was recognized as a generally safe disinfectant of fresh fruits and vegetables. One of the major pr...
Article
Harvest maturity of orange fruit is currently estimated based on total soluble solids (TSS). Juice TSS is analysed from few samples representing the entire orchard using a destructive method based on a refractometer. The technique restricts the number of representative samples due to its destructive nature. Significant loss of fruit occurs if the n...
Article
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This study investigated the efficacy of edible gum arabic (GA) and carboxymethyl cellulose (CMC) containing moringa (M) leaf extract as postharvest treatments for maintaining organoleptic quality and controlling Colletotrichum gloeosporioides on ‘Maluma’ avocado fruit. For the quality study, after the fruit was dipped into the treatments: GA 10%, G...
Article
In the current study, biochemical changes of avocado fruit cv. 'Carmen' and 'Hass' were evaluated during growth, development and maturation. The aim was to determine if exposure of fruit to sunlight could vary the biochemical compounds associated with maturity, and hence be among the causes of uneven maturity, and ripening. The current study also s...
Article
A reduction in photosynthesis results in a reduced CO2 assimilation rate and availability of carbohydrates essential for fruit growth and development. This study determined photosynthetic efficiency and photoprotection mechanisms within and outside leaf canopy positions in ‘Gem’ avocado orchards and their relationship with avocado fruit maturity. T...
Article
Lemon (Citrus limon L.) is one of the most cultivated citrus fruit in South Africa. In citrus packhouses, fruit are coated with commercial synthetic waxes to enhance shelflife. However, the use of waxes has been linked to peteca spot (PS) incidence in lemons. This study evaluated the efficacy of chitosan (CH) and carboxymethyl cellulose (CMC) incor...
Article
Unripe banana flour is a premium nutritious product with a potential to curb degenerative diseases through resistant starch and gluten free traits, however, with scant techniques to monitor adulteration practices. The objective of the present study was to determine the efficacy of visible–near infrared spectroscopy (Vis–NIR) spectroscopy (Vis–NIRS)...
Article
Extreme weather and climate events, such as very high temperatures, wind velocity and hail incidences that occur due to climate change and global warming, have detrimental effects on subtropical fruit orchards. Shade netting is one of the emerging techniques used by growers to protect their orchards against various biotic and abiotic stresses, such...
Article
Moisture content (MC), oil content (OC), fatty acid composition and rancidity are considered as major determinants of quality of nuts. These parameters are destructively quantified from a batch of representative samples used to estimate quality of nuts of an entire orchard. Although destructive techniques are helpful, they involve extensive sample...
Article
Rind biochemical properties play major roles in defence mechanisms against the incidence of rind physiological disorders of citrus fruit during cold storage. Hence, multivariate calibration models were developed to rapidly and non-destructively determine rind biochemical properties of citrus fruit from visible to near-infrared (Vis/NIR) spectra acq...
Article
BACKGROUND Nules Clementine’ mandarin was used to investigate the potential involvement of endogenous plant hormones in mediating the citrus fruit susceptibility to rind breakdown disorder (RBD). The effect of light exposure (viz. canopy position and bagging treatments) on the endogenous concentration of ABA, 7’hydroxy‐abscisic acid (7‐OH‐ABA), ABA...
Article
Full-text available
South African 'Hass' avocado fruit continue to show poor skin colour development during ripening, and a co-nundrum compromised export quality. In response to such a challenge, the South Africa Avocado Growers' Association (SAAGA) commissioned the Agricultural Research Council-Tropical and Subtropical Crops (ARC-TSC) to investigate the causing facto...
Article
Full-text available
The aim of this work was to investigate the role of 1-MCP, production region, harvest time, orchard slope and fruit canopy position on colour development of 'Hass' avocado fruit during ripening. 'Hass' avocado fruit were harvested from Tzaneen area for the 1-MPC trial, and from both Tzaneen and Mpumalanga areas for the orchard slope and fruit canop...
Chapter
The accuracy and robustness of prediction models are very important to the successful commercial application of visible to near-infrared spectroscopy (Vis-NIRS) on fruit. The difference in physiological characteristics of fruit is very wide, which necessitates variance in the type of spectrometers applied to collect spectral data, pre-processing of...
Article
Full-text available
Consumer preference for fruit without disorder influence purchase of fruit at both local and international markets. Recent trends in horticulture show that consumer preference is influenced by assurance that external appearance is linked with rewarding internal sensory quality. Therefore, the need for non-destructive evaluation of external and inte...
Article
Rind biochemical composition affect citrus fruit response to postharvest physiological stresses. Effect of canopy position within the tree on rind colour and antioxidant composition of ‘Marsh’ grapefruit was investigated during 9 weeks of postharvest storage. Fruit from inside canopy (IC) and outside canopy (OC) were harvested from KwaZulu-Natal (K...

Citations

... Compared to individual treatments, St+SWE had additive and synergistic effects to improve growth and productivity in mangroves. Similar observations have been reported in crop plants using a combination of PGPR bioinoculants and SWE biostimulants (Ngoroyemoto et al., 2020;Aremu et al., 2022). Despite the benefits of PGPR on the growth and yield of Salicornia and mangroves (Bashan et al., 2000;Komaresofla et al., 2019;Mathew et al., 2020;El-Tarabily et al., 2021a), the impact of the co-application of SWE and rhizosphere and/or endophytic PGPA in marine agriculture is still meager. ...
... Edible coatings have been highlighted as a potential technology to prevent postharvest infection and the associated fungal degradation of fruits [12][13][14]. The application of fruit coatings has demonstrated technological advantages such as better appearance, antibacterial and antioxidant properties, and improved taste [15]. Some coatings have already been tested on tropical fruits, including avocados and mangoes, with different degrees of effectiveness. ...
... The use of SETs and natural biostimulants are approaches that involve seed restoration or protection from abiotic and biotic stress. Such SETs and natural biostimulants have previously been sourced from fungi [24,25], bacteria [25,26], and seaweeds [27][28][29]. Microalgae and seaweeds can be used as biofertiliser [30,31] and as sources of biostimulants including PGRs [32,33]. ...
... The enhanced germination performance due to seed treatments (using various agents such as water and plant hormones) has been reported in various crops including maize (Zea mays, Farooq et al. 2008a), soybean (Glycine max, Zhuo et al. 2009), spinach (Spinacea oleracea, Chen et al. 2010), pepper (Capsicum annuum), Korkmaz and Korkmaz, 2009), and wheat (Triticum aestivum, Iqbal and Ashraf 2007), under both optimal and stressed environments (Paparella et al. 2015;Masondo et al. 2018). The treatment of seeds using biostimulants from natural origin represents one of the most innovative and promising strategies to improve seed germination, early protrusion of the radicle, emergence (appearance of a seedling through the soil), and seedling establishment under abiotic stress conditions (Zeng et al. 2012;Colla et al. 2014;Sharma et al. 2014;Garcia-Gonzalez and Sommerfeld 2016;Van Oosten et al. 2017; Barone et al. 2018;Makhaye et al. 2021). Various biostimulant and their active compound(s)/component(s) that promote seed germination and seedling growth are elaborated in the following sections and in Tables 1, 2 , 3, 4, 5, 6, 7, 8, 9, 10, 11. ...
... Thus, near infrared spectroscopy can provide a fingerprint of the content in a sample, especially in food and agro-products. Near infrared spectroscopy has been used in a wide range of investigations to find adulteration in foods and agro-products such as livestock (dos Santos Pereira et al., 2021a;Teixeira et al., 2021a;Mabood et al., 2020), flour (Ndlovu et al., 2021a;Ayvaz et al., 2021b;Tao et al., 2021), liquid agro-product (Tan et al., 2021;Valinger et al., 2021b;Du et al., 2021b), and herbs and spices (Castro et al., 2021;Cantarelli et al., 2020;. ...
... However, a limited number of research studies have been conducted on the use of Vis-NIR spectroscopy to detect food additives or contamination in food products. These studies included the detection of contamination in premium green banana flour with wheat [20] or adulteration in desiccated coconut powder [21]. Nevertheless, no study has been conducted on the detection of encapsulants in the production of butterfly-pea extract powder. ...
... Accelerated ripening and softening are major factors shortening the shelf life and restricting the supply chains of mango fruit. Ripening of the mango fruit is a genetically complex process triggered by an increase in ethylene production and respiration rate [28]. In the current study, both bagged and non-bagged mango fruits exhibited a significant increase in ethylene production and respiration rate up to 10 d of cold storage, suggesting the initiation of the ripening process. ...
... For instance, Daisy et al. [14] reported that gum Arabic (15%) maintained the ascorbic acid and β-carotene in 'Apple' mango stored at ambient temperature for fifteen days. Likewise, a study by Ncama et al. [15] revealed that moringa leaf extract (MLE) (2%) and carboxymethyl cellulose (CMC) (1%) preserved the ascorbic acid in 'Marsh' grapefruit during storage at 5 • C for sixty-three days. ...
... The rapid increase in total soluble solids generally exhibits prompt postharvest ripening of climacteric fruits (Bambalele, Mditshwa, Tesfay, & Magwaza, 2021;Liu et al., 2020;Saleem et al., 2020). The increase in total soluble solids takes place owing to the probable conversion of polysaccharides into simple sugar molecules . ...
... However, despite the adaptive potential of M. oleifera to agroecosystems, its development, growth, and production can decrease when the plant is exposed to thermal and water stresses [9][10][11][12], especially in semi-arid regions with high solar radiation levels, increased air temperature, and soil water restriction, conditions that could be further aggravated by environmental climate changes [13,14]. Thermal stress reduces seed germination and vigor in seedlings of M. oleifera [15,16] and increases the accumulation of non-structural carbohydrates, amino acids, and phenols [12]. ...