Effects of Nitrogen Concentration on Growth, Yield and Phytochemical Content of Persicaria minor Cultivated Using Hydroponics System

Abstract

Persicaria minor or locally known as kesum from the family Polygonaceae is a common herbal plant found in Malaysia. Hydroponic cultivation of kesum using deep water culture (DWC) system can be an alternative option for kesum growers in increasing crop yields. The deep water culture system is a method in which liquid fertiliser solution is given directly to the plant roots without any medium and water flow. The study’s main objective was to determine the effects of nitrogen concentration on growth, yield and phytochemical content of kesum cultivated using hydroponic system. Plants were grown under one of four nitrogen concentration solution regimes and the experiment was conducted under a side netted rain shelter. The four treatments comprised of 200 mg/L, 100 mg/L, 50 mg/L and 0 mg/L of nitrogen concentrations. The experiment was arranged in Randomized Complete Block Design (RCBD) with 4 replications. Plants were selected randomly and harvested eight weeks after planting. Plants grown supplemented with 100 mg/L of nitrogen concentration gave the best growth performance and biomass yield. They produced the highest plant height (78 cm) and fresh biomass yield (174 g per plant). Meanwhile plants supplemented with 50 mg/L of nitrogen concentration produced the highest Quercetin-3-glucuronide (Q3G) (98.261 mg/mL) and Quercitrin (61.367 mg/mL) compound compared to the other treatments. However, plants treated with 0 mg/L of nitrogen concentrations exhibited major nutrients deficiencies symptoms and die after 3 weeks of planting. Hence, it can be concluded that the kesum plants cultivated using hydroponics’ deep water culture system supplemented with 100 mg/L of nitrogen concentration gave the highest plant growth and biomass yields. However, to obtain higher Quercetin-3-glucuronide and Quercitrin compound, 50 mg/L of nitrogen concentration is recommended.