The influence of regular deficit irrigation applications on water use, yield, and quality components of two corn (Zea mays L.) genotypes

•We determine the effects of regular deficit irrigation on corn genotypes.•We examine the effects of water stress on protein content.•We determine the effects of deficit irrigation on sugar content.•Increasing water stress will decrease yield and quality of corn. The objective of the present study was to determine the mechanisms of tolerance of two corn (Zea mays L.) genotypes (Şafak and Ant-İ90) to water stress under five different irrigation treatments designated as full irrigation (I100) with no water stress and slight (I75), mild (I50), severe water stress (I25) and no irrigation (I0) treatments. The results showed that different irrigation levels applied has statistically significant effect on yield components such as anthesis–silking interval, plant height, ear diameter, ear length, kernel number and 1000 grain weight, except for ear number. In both of the genotypes, water deficit stress significantly (P≤0.01) increased glucose, fructose, and sucrose contents while it decreased protein content. The maximum grain yield was obtained from Şafak genotype under full irrigation, slight, mild, severe and full water deficit stress as much as 9.35tha−1, 8.34tha−1, 7.89tha−1, 5.56tha−1 and 3.63tha−1, respectively. The highest water use was observed in I100 treatment as 738.1mm for Şafak genotype, while the lowest was found in I0 treatment as 260.0mm for Ant-İ90 genotype. The highest water use efficiency was found in I50 as 15.7kgha−1mm−1 for Şafak genotype, and the lowest one was found in I0 as 5.5kgha−1mm−1 for Ant-İ90. It was concluded that Şafak was more tolerant genotype to water stress than that of Ant-İ90.