Photosynthesis and Harvest of Deltoid Synurus (Synurus delitodes) under Different Light Environments

Deltoid Synurus(Synurus deltoides) is perennial in Compositae that grows wild throughout Korea.  There is much edible fiber in the plant, so this prevent an adult's disease. Recently there are many studies for functions of Deltoid Synurus; antimutation activity, antioxidant activity, antiinflammatory activity (Ham et al., 1997; Lee, 2003; Woo et al., 2010; Park et al., 2004; Jung et al., 2008) and that contains β-cubebene, caryophyllene(Lee et al., 2012). This plant was acknowledged as a well-being food. So we researched the photosynthesis and harvest of Deltoid Synurus under different light environment for the high quality yield. Deltoid Synurus(Synurus deltoides) were sown in 105 cells traypot in March 2012 and raised in the grass house. These were planted by 30×20cm distance in the May in the field. Shading treatment carried out in the last ten days of the May, used 35%, 55% shading net sold at a market. The light density and temperatures under the different shading treatments was measured at the 1 meter from the ground from the May to the September. We examined the hardness of leaves, photosynthesis and the yield under the different shading. The data were analyzed by SPSS Statistics Program (Version 19.0) and are testified with Duncan's multiple range test Harvest weight per plant of Synurus deltoides grown under 0%, 35%, 55% shading treatments (35.9 g, 52.6 g, and 21.1 g, respectively). The hardness under 35% shading was 1.8 kg/cm² and tender compared of 2.3 kg/cm² under non-shading. The maximum photosynthesis rate was high under non-shading and 35% shading—12.9 and 12.6 µmol·m^-2·s^-1 CO₂, respectively. The dark respiration under 35% shading was 22.2 µmol·m^-2·s^-1 and lower than 28.5 µmol·m^-2·s^-1 under non-shading. The results show that the harvest and quality of Deltoid Synurus under 35% shading was the best.