NPK Fertilization Modulates Growth, Nutrient Uptake, and Soil Fertility in Chickpea (Cicer arietinum L.) under Greenhouse conditions

Abstract

The study was carried out from December 2024 to March 2025 in the greenhouse of the College of Science at Salahaddin University-Erbil, Iraq, to investigate the impacts of varying NPK nitrogen(N), phosphorus(P), and potassium (K) fertilization levels on the growth, nodulation, nutrient accumulation, and soil fertility of chickpea (Cicer arietinum L.). Nitrogen was given as urea at rates of 0,10,20, and 30 kg. ha-1, while Phosphorus as (triple super phosphate) and potassium as (potassium chloride), where applied at rates of 0,30,60, and 120 kg. ha-1 and combined NPK fertilizer with addition uniform dose. Different NPK fertilizer concentration applied to assess their effects on plant growth parameters nodule formation and diameter, shoot and root length. Additionally, the nutrient content in chickpea tissues and soil samples was analyzed to assess nutrient uptake and soil fertility changes. Experiment was laid out in Randomized Complete block design (RCBD), with three replications. Results showed that high value in fertilizer (N10), (P30), (K30) and(N30PK120). Statistical significance in nitrogen, phosphorus, potassium and NPK is significant at the measured (p<0.05-0.01), Phosphorus and potassium accumulation in soil and plant positive relationships, these findings highlight that balanced NPK fertilization, particularly moderate P and K inputs, improves chickpea performance and sustains soil fertility under greenhouse conditions.