Effects of pH and Phosphorus Concentrations on the Chlorophyll Responses of Salvia chamelaeagnea (Lamiaceae) Grown in Hydroponics

Abstract

Salvia chamelaeagnea (Lamiaceae) is a slow growing water‐wise evergreen shrub originat‐ ing from the western province of South Africa. It is an attractive landscape, and S. cha- melaeagnea is a medicinal plant. It is important to develop enhanced cultivation protocols that could result in high yield and high‐quality medicinal materials. Chlorophyll is a fundamental part of the light‐dependent reactions of the photosynthesis process. This chapter investigates the effects of four phosphorus concentrations and three pH levels of supplied irrigated water on the production of chlorophyll A, chlorophyll B, total chloro‐ phyll, leaf colour and the nutrient uptake of S. chamelaeagnea grown in hydroponics over an 8‐week period at the Cape Peninsula University of Technology. The treatments of pH 4, pH 6 and pH 8 at 31, 90, 150 and 210 ppm of phosphorus were received by 12 groups of plants and were replicated 10 times. The results indicated that at pH 4, P fertilization sig‐ nificantly (P < 0.05) induced a higher chlorophyll production of S. chamelaeagnea grown in hydroponics compared to other pH treatments (pH 8 and pH 6). Keywords: