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Bush tea (Athrixia phylicoides) belongs to the Asteraceae family. It is a popular beverage used as an herbal tea and as medicine for cleansing or purifying the blood, treating boils, headaches, infested wounds, and cuts, and the solutions may also be used as a foam bath. In some parts of South Africa, people drink bush tea for aphrodisiac reasons. Bush tea was grown under varying N, P, and K levels in all four seasons to determine the seasonal nutrient requirements for improved plant growth. Three parallel trials for N, P, or K one at each season were laid out in a randomized complete block design (RCBD) with six treatments replicated eight times. Treatments consisted of 0, 100, 200, 300, 400, or 500 kg·ha–1 N, P, or K. Parameters recorded were plant height, number of branches and leaves, fresh and dry stem mass, fresh and dry root mass, stem girth, fresh and dry shoot mass, leaf area and percentage leaf and root tissue N, P, and K. Results of this study demonstrated that, in all trials regardless of season, N, P, or K nutrition increased bush tea fresh and dry shoot mass, plant height, number of leaves, number of branches and leaf area. Regardless of season, the optimum level of N, P and K fertilization for bush tea on growth parameters was 300 kg·ha-1 N or P and 200 kg·ha-1 for K. No significant differences in number of flowers and buds (fall and winter), stem girth, fresh and dry root mass as well as fresh and dry stem mass were obtained.

The inner layers of the seed coat that remain attached to the cotyledons probably play a role in seed dormancy of Moringa oleifera. Cotyledons of seeds stored for one year showed no sign of deterioration. In some cells of the three-year-old cotyledons, the membranes of the protein bodies were deteriorated. Cell deterioration was also marked by the collapse of the cell wall adjacent to the intercellular cavity. The decrease in seed viability during storage is associated with the loss in membrane integrity as confirmed by the increase in electrolyte leakage. The longevity of seeds can be extended if they are stored within their fruits under favourable conditions.

Bush tea (Athrixia phylicoides L.) contains high concentrations of polyphenols that are the primary indicator of antioxidant potential in herbal teas. The objective of this study was to determine the seasonal effect of nitrogen (N), phosphorus (P), and potassium (K) nutrition on total polyphenol content in bush tea leaves. Treatments consisted of 0, 100, 200, 300, 400 or 500 kg·ha−1 of N, P, or K in a randomized complete block design under 50% shade nets. Three (N, P, and K) parallel trials were conducted per season (autumn, winter, spring, and summer). Total polyphenols were determined using Folin-Ciocalteau reagents and analyzed in a spectrophotometer. The results of this study demonstrated that, regardless of season, application of nitrogenous, phosphorus, and potassium fertilizers increased quadratically the total polyphenols in bush tea, with most of the increase occurring between 0 and 300 kg·ha−1 N, 300 kg·ha−1 P, and 200 kg·ha−1 K. Linear relationships between percentage leaf tissue N, P, and K with total polyphenols in bush tea were also observed. Therefore, for improved total polyphenol content in bush tea leaves, 300 kg·ha−1 N, 300 kg·ha−1 P, and 200 K kg·ha−1 N is recommended.

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Analysis of stem extracts identified large quantities of 3,4-dihydroxybenzoic acid and other similar phenolics. The exogenous application of 3,4-dihydroxybenzoic acid on Protea cynaroides explants in vitro significantly increased the root mass at 100 mg l −1 , but not at lower concentrations, while root inhibition was observed at 500 mg l −1 . HPLC analysis of cuttings during vegetative propagation showed a considerable increase in 3,4-dihydroxybenzoic acid levels from initial planting to when root formation took place, indicating for the first time that 3,4-dihydroxybenzoic acid may be an important phenolic compound in regulating root formation in P. cynaroides cuttings. HPLC analysis also identified caffeic, ferulic, gallic and salicylic acids in the cuttings.

The inability to induce rooting of in vitro-established Protea cynaroides microshoots has prevented the production of complete plantlets. A successful shoot-tip micrografting technique was developed using in vitro-germinated P. cynaroides seedlings as rootstocks and axenic microshoots established from pot plants as microscions. Thirty-day old seedlings, germinated on growth-regulator-free, half-strength Murashige and Skoog medium, were decapitated and a vertical incision made from the top end. The bottom ends of microshoots established on modified Murashige and Skoog medium were cut into a wedge ('V') shape, and placed into the incision. The micrografted explants were cultured in a growth chamber with the temperature adjusted to 25 ± 2°C, with a 12-h photoperiod. Best results were obtained by placing the microscions directly onto the rootstock without any pre-treatments. Dipping the explants in anti-oxidant solution or placing a layer of medium around the graft area led to the blackening of the microscion.Abbreviations EDTA Ethylenediaminetetraacetate -BAP 6-Benzylaminopurine -GA 3