Nitrogen Source and Dose Effects on Spinach Yield and Total Nitrogen Content Across Storage Periods

Özet

Spinach (Spinacia oleracea L.) cultivation is gaining prominence due to increasing interest in health and wellness. Nitrogen (N) is crucial for spinach growth, and traditional fertilization practices are being reconsidered for their environmental impact. In this study, we investigated the effects of different N sources, doses (25, 50, 100, 200, and 400 mg N kg^-1), and storage durations on dry weight and total N content of spinach plants. Four N sources, including ammonium sulfate (AS), calcium nitrate (CN), slow-release ammonium soil (SRAS). The spinach plants were subjected to storage for 0, 5, and 10 days, and their dry weight and total N content were measured. The results revealed significant variations in spinach dry weight and total N content among different nitrogen treatments and storage periods. Calcium nitrate consistently promoted higher dry weight and total N content, reaching 5.40% for total N at 400 mg kg^-1 on Day 0, compared to other N sources across various storage durations. The YR and SRAS also showed high total N levels, with values consistently above 4% at the highest dose. The SRAS exhibits potential for prolonged efficacy, particularly at higher doses and later storage stages. Initially, at Day 0, the total N content in SRAS treatment was highest and decreased significantly by Day 5, with a slight recovery by Day 10. The correlation between dry weight and total N content became more pronounced with longer storage periods and higher N doses and sources. Yeast residue exhibited the strongest positive correlation between dry weight and total N content, suggesting its effectiveness in promoting dry weight. In addition, a strong positive correlation between dry weight and total N content underscores the crucial role of N management in determining spinach yield and quality. The results showed that CN and SRAS, particularly at higher doses, were the most effective N sources for promoting dry weight in spinach. The findings underscore the importance of selecting the appropriate N source and dose is crucial for optimizing spinach yield and quality during storage.