Effect of Fertilizer and Light Intensity on Leaf Color in Ludwigia repens

Abstract

Ludwigia repens is an economical aquatic plant for export. It is an indigenous aquatic plant of North America. Under the optimum of fertilizer and light intensity, the leaves show red color on ventral side (adaxial) and greenish purple on dorsal side (abaxial) which is popular for aquarium. Therefore study on L. repens cultured by using the combination of 25-5-5 fertilizer at rates of 0, 10, 20 mg/l and light intensity at 500-1500 Lux and 2000-5000 Lux was conducted. After 8 weeks, the results showed that there was no interaction (P>0.05) between fertilizer and light intensity. However, the best result to increase leaf color (red) and growth of L. repens was the culture by fertilizer at rates of 10 and 20 mg/l (P<0.05).
The concentration of fertilizer at 10 mg/l under the light intensity 1470-1900 Lux is optimum for L. repens growth and could increase leaf color, leaf size, height, number of leaves and weight. Consequently, the results further demonstrated the efficient method for good quality L. repens production.