Effect of Drainage Ratio in Nutrient Supply on Growth and Yield of Paprika (Capsicum annum L.) in Long-term Recycling Hydroponic Cultivation in South Korea

Due to the global climate change, sustainable agriculture has become necessary. Regarding to paprika (Capsicum annum L.) cultivation, use of circulating hydroponic system can contribute to prevent water pollution and reduce waste water. Even though many of paprika farms in Korea install the circulating hydroponic system, few farms actually use it. This is due to the fact that there is no useful data that can be applied for long-term paprika cultivation under circulating hydroponic system. This study, therefore, was conducted to provide practical information to paprika farms with circulating hydroponic system by analyzing the effect of drainage ratio in water supply on the growth and yield during the entire growth period of paprika. This experiment was comprised of four treatments with different drainage ratios in water supply; 100% nutrient solution(NS), 80% nutrient solution + 20% drainage(D), 70% NS + 30% D and 50% NS + 50% D. The experiment was performed for 35 weeks, from spring to winter in 2015. Based on the growth stages of paprika, growth characteristics were investigated every week, and each investigation was categorized from group 1 to group 5. The results of this study showed that leaf area and total yield of paprika were reduced whereas flowering position was prolonged as the HWS ratio increased. There, however, was no significant difference in total yield from group 3 to group 5 as well as between treatment of 70% NS + 30% D and 80% NS + 20% D. In addition, total yield in 70% NS+30% D was 92% of that in 100% NS. These results show that growth and yield of paprika are not affected by use of recycled nutrients during long-term hydroponic cultivation. These results will be introduced to paprika farms, which would contribute to rapid expansion of using the circulating hydroponics system in Korea.