effects of deficit irrigation on yield and yield components of maize and determining of water productivity in nekuabad irrigation network

to illustrate the impact of various levels of deficit irrigation on yield and yield components of maize cultivars, a study was conducted based on randomized complete blocks as a split plot design with 3 replicates and two treatments for three crop seasons. four levels of deficit irrigation including: conventional, 100, 80, and 60% of water level use were considered as main plots and two varieties (704 and 647) as subplots in a experimental site located in shahid fozveh research station. significant differences (p≤0.05) were noticeable in grain yield, as well as depth and column of kernel among the irrigation treatments. in addition, the effects of cultivars on grain yield, 1000 kernel weight, number of kernel per ear row, number of kernel per column, and depth of kernels were non significant. results showed that, a decrease of 36 percent water applied (60% irrigation level treatment) compared to full irrigation, yield declined 11.4% and a decrease of 20 percent water applied (80% irrigation level treatment) compared to full irrigation, yield declined only 2%. based on the results and considering the quantitative characteristics of the crop, it was established that for the deficit irrigating of maize, the 80% irrigation level is the most advantageous treatment when water is not limited. however, when higher water productivity and the possibility of using the water saved are taken into consideration during severe drought conditions, 60% irrigation level treatment is recommended.