Effect of Light, Aeration and Nutrient Concentration on Wolffia (Wolffia globosa (Roxb.) Hartog & Plas) Growth

Abstract

Background and Objective: Wolffia (Wolffia globosa (Roxb.) Hartog & Plas) is a nutritious plant that is used as food for humans and animals. In this study, the work aimed to determine the influence on the growth of W. globosa of light (non-shaded and shaded 50% of light intensity), aeration (aeration and without aeration) and Hoaglandʼs solution concentration of 1/2, 1/4 and 1/6 compared with the control (full strength Hoaglandʼs solution). Materials and Methods: Cultures of 100 g of W. globosa were grown in plastic boxes (32×40 cm) containing 3 L Hoaglandʼs solution. Supplied during a 12 hrs photoperiod the light intensity was 10,000 lux. W. globosa was culture for 30 days. The fresh weight was recorded every 5 days until day 30 when the chlorophyll A and B contents were determined. Results: It was found that on days 15 and 20 the fresh weights of W. globosa cultured in 1/2 and 1/4 Hoaglandʼs solution were the highest. Wolffia globosa cultured without shading had fresh weights higher than the 50% light intensity with statistical significance. In contrast, the 50% light intensity showed a higher total chlorophyll content than the non-shaded, with statistical significance at the 95% confidence level. Wolffia globosa without aeration had a higher fresh weight than that with aeration statistical but this did not affect the amount of chlorophyll. Conclusion: Therefore, appropriate conditions for W. globosa are a dilute nutrient solution and light at 50% light intensity without aeration.