A Study of Oxygenation Techniques and the Chlorophyll Responses of Pelargonium tomentosum Grown in Deep Water Culture Hydroponics

Abstract

<jats:p><jats:italic>Pelargonium tomentosum</jats:italic> Jacq.; the peppermint-scented pelargonium, is an herbaceous groundcover indigenous to the Western Cape of South Africa. Volatile oils are produced by this plant, which are used in the fragrance industry. Studies on other <jats:italic>Pelargonium</jats:italic> species have shown chlorophyll content may affect the yield of essential oils. This study was carried out to investigate the viability of growing <jats:italic>P. tomentosum</jats:italic> in deep water culture (DWC) hydroponics and how best to aerate/oxygenate the nutrient solution to increase the chlorophyll content within leaves. The experiment was conducted over a period of 74 days, 16 different methods of oxygenation were applied to 9 replicates. The control had passive aeration; the treatments were made up of air-pumps, vortex oxygenators, and the application of hydrogen peroxide at various frequency intervals; these were combined with each other and run as separate oxygenation methods. The measurement of the chlorophyll content of plant leaves has been established to be an accurate way of establishing vigor, health, and levels of stress. It was found that the combination of high-frequency application (every third day) of hydrogen peroxide, vortex oxygenation, and air-pump injection (both operational for 24 hours/day) which formed treatment 11 (APVHa), yielded the highest production of chlorophyll within all the replicates differing significantly (<jats:italic>P</jats:italic> ≤ 0.001) from the control and other treatments.</jats:p>

Effect of Hydrogen Peroxide on the Growth, Fruit Set, Yield andQuality of Ewais Mango Trees

“…The treatment with 5 mM H 2 O 2 appeared healthier than those of the control and exhibited a higher total chlorophyll content (2.25 -2.9) fold in comparison to that of untreated trees in both seasons. Similar positive effects of H 2 O 2 chlorophyll content were reported by Butcher et al (2017) in pelargonium tomentosum and Khandaker et al (2012) in wax apple…”

Growth characteristics, chlorophyll content and nutrients uptake in

“…Similarly, significant variability was observed in the chlorophyll content of Zea mays and Sorghum bicolour cultivated in soils amended with organic and inorganic fertilisers (Amujoyegbe et al 2007). Although outside the scope of this research, a combination of an airpump, high-frequency H 2 O 2 application, and vortex oxygenation was reported to have yielded the highest mean value of chlorophyll in Pelargonium tomentosum (Chen et al 2010;Butcher et al 2017), suggesting that oxygenation may drive photosynthesis through increased chlorophyll production. Findings from this research, therefore, corroborate what has been reported in earlier literature; that nutrient application increases chlorophyll content.…”

A Survey of Smart Hydroponic Systems

“…In this system, the growth medium is made up of Styrofoam, which floats directly on the nutrient solution. Oxygen delivery is the difficult part of this system [13]. Since the plants' roots are completely submerged in the nutrients a system of air pump and air stone provides them with oxygen.…”