Effects of Different Application Rates of Organic Compound Fertilizer on Young Squash Growth and Soil Chemical Properties under Plastic Film House

Abstract

To determine the replacement ratio of organic compound (OC) for basal application of inorganic fertilizers, the effects of different rate of OC on young squash (Cucurbita moschata) plant growth and soil chemical properties of plastic film house were investigated. The OC were applied at 50% (OC50+N50), 100% (OC100), and 150% (OC150) as the basal amount of inorganic nitrogen fertilizer recommended by soil fertility test, and the treatment were compared with inorganic NPK and PK treatment. The yield of young squash in OC150 treatment was similar to NPK treatment and higher than PK. In OC50+N50, OC100, and OC150 treatments, nitrate concentration and electrical conductivity (EC) were similar to NPK treatment. Relative nitrogen use efficiency of young squash ranged 17~37%. These results suggest that OC application as the basal dressing at the 150% level could be best rate to minimize nutrient accumulation of soil and to ensure the yield of young squash. Further study is required to evaluate effect of long-term application of OC on soil sustainability and young squash productivity. Changes of young squash yield according to replacement ratio of basal amount of nitrogen fertilizer with organic compound (OC) fertilizer. N, P, K, and OC mean nitrogen, phosphate, potash fertilizer, and organic compound, respectively. Treatment Fresh fruit weight Relative yield index† kg/10a % PK 8,607b† 96.0 NPK 8,960ab 100.0 OC50+N50 8,980ab 100.2 OC100 9,013ab 100.7 OC150 9,350a 104.5 †DMRT (p < 0.05). †Relative yield of other treatments to NPK treatment.