Effect of Irrigation Frequency on Growth and Functional Ingredient Contents of Gynura procumbens Cultivated in Hydroponics System

Gynura procumbens (Family Asteraceae) is a medicinal plant commonly found in tropical Asian countries such as Malaysia, Indonesia, Thailand, China, and Vietnam. It is widely used as a traditional medicine in many different countries for the treatment of a variety of health ailments such as kidney discomfort, hypertension, constipation, diabetes mellitus, and rheumatism. The objective of this study was to investigate the effect of irrigation on growth and functional ingredients of Gynura procumbens. Gynura procumbens were planted in a greenhouse on April 24 (2019), and irrigation was carried out throughout the entire growth period at 12, 24, 48, 72hour cycles using drip hydroponics system. The total height of Gynura procumbens became higher with shorter irrigation cycle, whereas a smaller height was recorded with the longer periods. The maximum yield was recorded for 12 - 24 h irrigation cycle, but it tended to decrease as the irrigation cycle became longer. The leaf marketability based on the irrigation cycle, leaf length, leaf width, leaf weight, and leaf thickness were best for the 24 h irrigation cycle treatment. The total polyphenols was higher for the 72 h irrigation cycle treatments compared to the others. Vitamin C concentrations were high at 48 and 72 h irrigation cycle treatment. Hence, the growth of Gynura procumbens based on irrigation cycle was maximum at 24-hour, and total polyphenol and vitamin C content was highest at 72-hour irrigation cycle treatment. Effect of irrigation frequency on antioxidant contents of Gynura procumbens. Numbers with the same letter within a column are not significantly differed (Duncan’s test, p < 0.05).