*3.1.1 Fertigation and its effect on crop production*

Fertigation is the synchronous supply of nutrients or soluble fertilizer and water to the soil through drip irrigation system (**Figure 3**). The introduction of fertigation to crop production proffers a solution to the problem of flooding and overfertilization. Water and liquid fertilizer are harmoniously applied to the rhizosphere which makes

*Fundamentals of Irrigation Methods and Their Impact on Crop Production DOI: http://dx.doi.org/10.5772/intechopen.105501*

**Figure 3.** *Schematic illustration of fertigation system.*

nutrients to be readily available for plant uptake. Fertigation results in increased crop yield and more efficient fertilizer usage [8]. Apart from increasing crop yield, fertigation reduces nutrient losses to the environment. Plants easily absorb soluble fertilizer thereby reducing nitrogen losses as nitrous oxide to the atmosphere. A well-designed fertigation system takes into consideration the appropriate rate of fertilizer and water, duration and frequency of supply to improve water, and nutrient uptake of the crop while at the same time reducing nutrient loss via leaching [9]. An appropriate liquid fertilizer applied through fertigation reduces leaf burn, stem scorching, and root death as mostly observed in the direct application of solid inorganic fertilizer close to the root zone of crops. Furthermore, fertigation reduces disease and pest infestation on crops, attributable to dryness of the plant shoot thereby creating a non-conducive environment for pathogens. The system was created to maximize the use of available water and mineral resources; thus, preventing runoff as it is not affected by wind.

To improve crop production through fertigation, the application of fertilizer should be done optimally to reduce acidification of the soil, and environmental degradation [10]. However, in case of overfertilization with the use of fertigation, continuous and frequent application of water regime should follow to reduce fertilizer concentration at the root region. Previous reports have documented that the use of fertigation increased both nutrient-use efficiency and water-use efficiency of crop. Nutrient use efficiency increased by 25%, and nitrogen and potassium application reduced by 20% as compared to the use of solid inorganic fertilizer [11]. Also, Ashrafi et al. [12] reported that the absorption rate of solid inorganic fertilizer was estimated to be 10–40%; whereas, the absorption rate of similar concentration on fertigated field was estimated to be 90%. Cotton yield increased by 50% on fertigated plots when compared to cotton supplied with surface irrigation with direct fertilizer application [13]. According to Hebbar et al. [14], drip fertigation enhanced tomato yield by 20–30% as compared to furrow irrigated tomatoes. The yield of Chili was also reported to increase by 52% and saved 40% and 50% of water and nitrogen, respectively through fertigation compared with a check-basin irrigation treatment [15]. Irrigation and nutrient management are the most effective methods for increasing agricultural output [16], and both management can be accomplished by fertigation. However, for successful use of fertigation, knowledge of soil fertility and crop nutrient uptake requirement is necessary.
