Drip fertigation in field crops: Effects on productivity, resourceuse efficiency and sustainability

Abstract:

Water scarcity and poor nutrient use efficiency have been identified as key limiting factors in agriculture that impact significantly on its productivity and sustainability. The conventional practices of flood and furrow irrigation have low water efficiency and often result in significant losses of both water and nutrients through evaporation, surface runoff, and deep percolation. Therefore, drip irrigation has emerged micro-irrigation techniques, delivering water directly to crop root zone and significantly reducing water losses. In addition to water, the practice of supplying nutrient through irrigation water improves the efficiency of resource utilization by providing the required amounts of nutrients to the crops' active root zone uniformly. Fertigation involves the application of fertilizers in frequent and smaller dosages during various growth stages of crops. It has been shown to improve crop yield, reduce yield variability, enhanced nutrient use efficiency and water use efficiencies (NUE and WUE) respectively, and lower labour costs compared to conventional crop growing methods. Also, the practice is likely to minimize crop cultivation expenses since it resources more efficiently. However, performance is influenced by factors such as soil texture, irrigation frequency, crop type, quality of water used, fertilizers used and their solubility, and water distribution uniformity. This paper gives an insight into the mechanisms involved in drip fertigation systems, fertilizer source, scheduling of fertigation, and the impact of drip fertigation on crop yield, Nitrogen Use Efficiency (NUE), Water Use Efficiency (WUE), and water productivity. It also discusses limitations, technological advances, and future research priorities in the field.