How Irrigation Water Affects the Yield and Nutritional Quality of Maize (Zea mays L.) in a Temperate Climate

Soil water deficit has an adverse effect on crop productivity and is one of the main limiting factors of global food security. Field experiments were conducted in Vojvodina, Serbia, to expand and improve knowledge about the effects of different levels of irrigation on maize grain yield and quality. The studied irrigation treatments were: full irrigation (I-100), 75% (I-75) and 50% (I-50) of I-100, and no irrigation (I-0)-rainfed. The irrigation level affects maize grain yield; protein, starch, and oil content; and mineral composition. The results show that that yield decreases with increasing water deficit in three study years. On average, full irrigation results in the highest oil content and rainfed conditions in the lowest. The starch content increases and the oil content decreases with decreasing irrigation. Irrigation significantly increases the concentrations of K, Mg, Fe, Mn, and Zn, and reduces the Ca concentration compared to the rainfed treatment. A 25% water deficit (I-75) has a positive effect on certain maize grain nutrients and the yield is significantly reduced. The highest grain yield and oil content are achievable with full irrigation. For good nutrientional quality of maize, treatment I-75 can be proposed under similar soil and climate conditions.