The effect of foliar application of different potassium fertilizers on growth, quality, and yield properties of lettuce
Makaleler > Tam Makale · 2025
Yazarlar: Neriman Tuba BARLAS, Mina Najafi, Hakan ÇAKICI
Journal of Plant Nutrition, SCI Expanded İndekslerine Giren Dergi, Uluslararası, Wos, 2025, cilt 48, ss 3366-3376
DOI: 10.1080/01904167.2025.2513403
Özet
In this study, the effects of different potassium (K) sources applied as foliar application on the growth, quality (plant root and shoot weight, plant root and shoot length, total and discarded leaf numbers, stem diameter, leaf area index), and yield (total and marketable) properties of lettuce were investigated. The experiments were conducted in a farmer’s field located in Ödemiş district of İzmir province (Türkiye), under the Mediterranean climate. The trials were set up using a randomized block design with five replications and repeated over two production seasons (2022 and 2023). Iceberg lettuce (Lactuca sativa) was used as the test material, and the treatments included a control group (no foliar application) alongside potassium sources such as Potassium Nitrate (KNO3, 46% K2O; 3 g/L per decare), Potassium Thiosulfate (25% K2O; 5.5 ml/L per decare), and Potassium Phosphite (25% K2O; 5.5 ml/L per decare). In both years, the experiments began in September and lasted 54 days in the first year and 58 days in the second. According to the research findings, potassium nitrate fertilizer had a significant impact on growth parameters in both years. The applications of potassium thiosulfate and potassium phosphite had comparable effects on growth and development. Plant height, shoot biomass, and total plant weight were found to be highest with potassium nitrate application in both years. Root length was highest with potassium phosphite application in both years. Yield was also highest with potassium nitrate application, reaching 3261 kg and 3306 kg per decare in the first and second years, respectively.