Yields and Sugar Content in Melon(Cucumis melo) by the Different Nitrogen and Potassium Fertilization Levels in Protected Cultivation.
Ju Young Lee1, Jae-Hong Park1, Byoung-Choon Jang1, Suck-Kee Jung1, Byung-Koo Ahn2, So-Hyeon Park3, Su-Yeon Lee3, Yang-Ho Park3, Ku-Suk Jung3, Ki-Sang Lee3, and Young-Sang Yoon3. (1) Division of Plant Nutrition, National Institute of Agricultural Science and Technology, RDA, 250 Seodun-dong, Suwon, 441-707, South Korea, (2) Kochang Watermelon Experiment Station, Yesan, South Korea, (3) Kongju National University, Kongju, South Korea
This study was carried out to investigate relationship between yields and sugar contents in protected-film-cultivated melon (Cucumis melo) by different nitrogen and potassium fertilization levels. Melon plants, cv. Ales elite, were transplanted on April, 2005. As a result of analyzing soil chemical properties used in experiment, EC, organic matter, total nitrogen, Av. P2O5, K, Ca, and Mg were 1.19 dS m-1, 11.2 g kg-1, 0.4g kg-1, 104 mg kg-1, 0.4, 7.5, 1.2 cmol kg-1, respectively. The N-P-K levels of four different established were 11-4-14, 13-4-16, 15-4-18, and 17-4-20. At harvesting season (80 days after planting), we measured fruit yields and sugar contents in melon fruit using portable refractometer. Fruit yields of melon grown in different fertilization levels such as 11-4-14, 13-4-16, 15-4-18, and 17-4-20 were 3,526, 3,549, 3,019, 2,557 kg 10a-1, respectively. An excessive N-K application resulted in a decrease of yields due to prolonged vegetative growth. Also, Sugar contents in melon fruit harvested under different N-K supply, 11-4-14, 13-4-16, 15-4-18, and 17-4-20, were 13.8, 15.0, 15.0, and 16.0 obrix, respectively. High N-K supply, 17-4-20, promoted higher sugar accumulation in melon fruit. Considering the relationship between yield and sugar, value as marketable product is the best at 13-4-16 of N-P-K application. Key words : melon, yield, sugar content.