Indigenous knowledge of bush tea (Athrixia Phylicoides) and effect of fertigation frequency and growing medium on plant growth

Abstract

Bush tea (Athrixia phylicoides) is a medicinal herbal tea, which is used for cleansing or purifying the blood, treating boils, bad acne as well as infected wounds and cuts. A. phylicoides also has the potential to be used as an ornamental cut flower due to its beautiful flowers. Because of the many uses of bush tea, it faces problems of being over harvested and exploited. Therefore, there is a need to study more about the plant for possible domestication. A questionnaire survey was conducted in selected villages of Thohoyandou and Nzhelele in Venda, Limpopo Province, by means of personal interviews. The aim of the survey was to gather indigenous knowledge and validate the uses of bush tea from the local people. Interviews were conducted on three types of respondents, viz. traditional healers (31%), street sellers (25%) and bearers of indigenous knowledge (44%). A total of one hundred respondents were interviewed. One important finding of the study was that people from the area of study possess a remarkable knowledge of the plant and its uses to treat a wide range of physical ailments. The bush tea plant is used as medicine, health tea as well as a traditional broom. Some of these ailments that could be treated using bush tea were headaches, stomachache, influenza and leg wounds. It is known to have aphrodisiac properties and it can also be used to cleanse the womb, kidney, and veins and to purify blood. The plant was harvested in different ways depending on the reason for harvesting. Results from the survey indicated that the majority of the respondents had no interest in propagating the bush tea plant, few respondents showed interest in propagating the plant. They also showed enhanced knowledge about the uses of other medicinal plants. A tunnel experiment was also conducted at the Hatfield Experimental Farm of the University of Pretoria in South Africa. The effects of growing media (pine bark and sand) and fertigation frequencies (0.4 ℓ/day, 1 ℓ/day, 2 ℓ/day, 2 ℓ/2nd day and 2 ℓ/ week) on growth and yield of bush tea were studied. Growing media and fertigation frequencies significantly affected the growth performance and yield of bush tea. The growth rate of bush tea between the autumn season and winter season was higher than between winter and spring season. Greater number of stems and shoots were observed in sand grown plants as compared to pine bark grown plants. Sand grown plants had a higher root mass as compared to those of pine bark grown plants over both seasons, with nonsignificant differences in the dry root mass in winter (90 days after planting). Plants grown in sand had significantly longer roots (P≤ 0,05) than plants grown in pine bark at 90 days after planting. However, at 180 days after planting the differences in root lengths were no longer significant. Fertigation frequencies caused significant differences in growth performance and yield of bush tea. Plants fertigated with 1 ℓ/day were significantly the tallest, followed by plants fertigated with 0.4 ℓ/day, 2 ℓ/day, 2 ℓ/2nd day and 2 ℓ/ week. Our results confirmed that bush tea could grow up to 1 metre high (1.08 m). In addition, fertigation frequency of 1 ℓ/day resulted in plants with greater stem and leaf mass (both fresh and dry), thus higher yields. Fertigation frequency of 2 ℓ/day was found to be too high and hence reduced oxygen supply to the roots and consequently retarded above plant growth. Sand grown plants also produced more flowers than pine bark grown plants. Overall, plants grown in sand media had superior stem and shoot mass, leaf mass, root mass and flower mass compared to plants grown in pine bark. Plants that received insufficient amount of water (2 ℓ /week) resulted in stunted growth and produced the least yield. In conclusion, bush tea plants performed better in sand growth media than in pine bark growth media. An optimum application rate of 1 ℓ/day was ideal for growth and performance of bush tea as the plant performed better under this fertigation frequency.