Evaluation of Chickpea Production under Different Management of Irrigation and Nitrogen Fertilizer

Background: Chickpea is a prominent leguminous crop cultivated in the West Asia and North Africa (WANA) region. Historically, it is planted during the spring season as a rainfed crop in the area, characterized by its unpredictable and frequently inadequate precipitation. Methods: To examine the impact of various levels of irrigation and nitrogen fertilizer on the yield and yield components of the Adel cultivar of chickpea, a factorial experiment was conducted based on a randomized complete block design with four replications at the research farm in Esfarayen Region in Khorasan-Iran (36.92 N, 57.55 E) throughout the 2022 and 2023 growing seasons. The experimental treatments included three levels of nitrogen: 30, 75 and 150 kg ha-1 as urea fertilizer. The irrigation was applied at three levels: full irrigation, one supplementary irrigation at the flowering stage and two supplementary irrigations at the flowering and pod filling stages. The studied traits included grain yield, biological yield, the number of pods per plant and the number of seeds per pod. Result: Our results showed that different levels of irrigation and nitrogen fertilizer had a significant effect on the number of seeds per pod, pods per plant and biological and grain yield. The interaction effect of irrigation and nitrogen fertilizer was significant for all studied traits. In this study, the interaction between the full irrigation treatment and 75 kg N ha-1 resulted in a significant increase in all traits (except biological yield) compared to other treatments. Furthermore, one irrigation at the flowering stage with 150 kg N ha-1 caused a significant decrease in all of the studied traits. The combination of full irrigation and 150 kg N ha-1 treatment had the highest biological yield (8.9 t ha-1), while its grain yield was 1854 kg ha-1. Therefore, by maintaining moisture levels during the critical period of chickpea growth and utilizing balanced nutritional levels, particularly nitrogen at rates of 30 and 75 kg ha-1, the yield of chickpea can be increased.