Biostimulants such as seaweed extracts are emerging as crop management products that can enhance crop productivity and nutritional quality under abiotic stress conditions. Therefore, this study aimed to assess the effectiveness of a seaweed-derived biostimulant (Kelpak^®) in alleviating salinity stress in spinach. A greenhouse experiment which consisted of five treatments (T₁ = Control plants (no NaCl or seaweed extract (SWE), T₂ = plants subjected to 300 mM NaCl without SWE, T₃ = 300 mM NaCl + 1% dilution of SWE, T₄ = 300 mM NaCl + 2.5% dilution of SWE, and T₅ = 300 mM NaCl + 5% dilution of SWE) was conducted. The results showed that salinity without the addition of SWE reduced crop growth, relative water content, chlorophyll, and nutritional quality. Similarly, salinity induced severe oxidative stress, indicated by excessive amounts of superoxide radicals, malondialdehyde and the upregulation of catalase, peroxidase, polyphenols, and flavonoids. Interestingly, plants treated with 5% SWE displayed a substantial enhancement in crop performance, reduction in oxidative stress, and improved nutritional quality, characterised by considerable amounts of minerals, proximate constituents, and vitamins. These results support the use of seaweed extract (Kelpak^®) as a biostimulant in enhancing growth and nutritional quality of spinach under saline cultivation.

The current reliance on pesticides and synthetic fertilizers has been vital to sustain and increase agricultural production. The continuous, excessive use of these traditional practices has negatively affected consumer health and burdened the ecosystem. The use of plant extracts as a tool to minimize agrochemical inputs has been extensively investigated; these extracts have the ability to improve both plant growth and agricultural productivity. Therefore, this study was conducted to determine the effect of foliar plant extract application on potato growth, as well as on certain physiological and yield attributes. From four weeks after planting onwards, five healthy, equal-sized potato plants per treatment received various foliar plant extract applications. These extracts included brown seaweed Ascophyllum nodosum extract (ANE), aloe vera leaf extract (AVE), garlic bulb extract (GBE), and moringa leaf extract (MLE). The treatments were repeated weekly until harvesting. Application data regarding growth and physiological parameters were collected weekly. The pre-harvest foliar application of various plant extracts significantly enhanced (p ≤ 0.05) the plant growth, physiological, and yield attributes of potatoes. The best growth and yield responses were observed following ANE and MLE application. Plant extracts have shown beneficial effects on other crops as well, but further validation of these effects is still necessary in order to popularize and commercialize such applications.

The marketability of fresh granadilla (Passiflora edulis) fruit is significantly reduced by oxidation reactions occurring in its exocarp, which is not directly linked to the organoleptic quality of its arils. However, organic means of mitigating this are not topical in research. This study investigated the potency of moringa (Moringa oleifera)-based coating to preserve antioxidant compounds in granadilla. Physiologically mature fruit of equal size were assigned to a completely randomized design experiment at the North-West University Farm Laboratory. The fruit samples were coated with 2% xanthan gum (commercial coating), 2% moringa, or 2% rosemary coating and kept at shelf-life conditions (25 ± 2 °C; 40 ± 5%RH) for 5 weeks while sampling at weekly intervals. Correlations between the measured parameters were confirmed prior to regression analysis. Significant (p < 0.05) differences were observed in weekly changes in the exocarp pH, total antioxidant compounds (TAO), tartaric acid (TA), malic acid (MA), and citric acid (CA). At the end of storage, the moringa- and xanthan-coated fruit had the highest exocarp pH (7.8) and TAO (0.87 mg/g). Moringa-coated fruit had higher TA and MA (6.0 and 5.36 µg/g, respectively) as well as a significantly higher CA (0.51 µg/g) preserved than the other coatings. Strong correlations between MA and TAO (r > 0.82), as well as TA and TAO (r > 0.86), indicated the potency of developing TAO estimation models using multivariate data from the organic acids. Pre-processed data regression models were developed but were limited by the amount of data collected. Models developed similarly can be used for sustainable TAO assessment as a latent variable to minimize toxic waste that results from wet chemistry analyses.

The current reliance on pesticides and synthetic fertilizers has been vital to sustain and even increase agricultural production. The continuous, excessive use of these traditional practices has negatively affected consumers’ health and burdened ecosystems. The use of plant extracts has the ability to improve plant growth and agricultural productivity. This study was, therefore, conducted to determine the effects of foliar plant extract application on potato growth, as well as on certain physiological and yield attributes. The treatments included extracts of the seaweed Ascophyllum nodosum, aloe vera leaves, garlic bulbs and moringa leaves. From four weeks after planting onwards, five healthy, equal-sized potato plants received 50 mL of the above-mentioned plant extracts as foliar applications. These treatments were repeated weekly until harvesting. Data on growth and physiological parameters were collected weekly. Pre-harvest foliar application of various plant extracts significantly enhanced (p ≤ 0.05) the plant growth and yield attributes of the potatoes. The best growth and yield responses were observed following ANE and MLE applications. A positive influence of various foliar plant extract applications on the growth and yield of potatoes was demonstrated. Further validation of the response of other crops is still necessary to promote the adoption of this approach.