Investigating the effect of dificit irrigation and mulching on the yield of fodder corn (Zea mays) under tape drip irrigation in KhorramAbad region

In order to investigate the effects of deficit irrigation and organic mulch on wet matter, dry matter, plant height, wet yield productivity, dry yield productivity and leaf area of corn forage (SC. 704) in Khorramabad region, an experiment based on the factorial experiment with a basic design of randomized complete blocks with three replications was conducted. The first factor of the experiment consisted of four levels of irrigation (100, 80, 60 and 40% of water requirements) and the second factor included three levels of organic mulch (no mulch (control), using 7.5 ton/hectare and 15 ton/hectare mulch). In this research, drip irrigation system (Tape) was applied and class A evaporation pan was used to determine the water requirement of the plant. The results showed that the mutual effects of deficit irrigation and organic mulch were significant at the 5% probability level. The maximum amount of wet matter (99.05 ton/ha), dry matter (31.15 ton/ha), plant height (2.38 m) and leaf area (7511cm2) were observed in the treatment of 100% water requirement and using mulch (15 ton/ha) which increased by 24.7%, 18.03%, 5.8% and 48.38% respectively compared to the control treatment. The maximum amount of water productivity for wet and dry matters were 14.56 and 4.57 kg/m3 which were obtained in the treatment of 80% water requirement and using mulch (15 ton/ha). The minimum amount of water productivity for wet and dry matters were 10.09 and 3.35 kg/m3 which were obtained in the treatment of 100% water requirement without using mulch.  Thus, in this region, irrigation based on 80% water requirement and using mulch (15 ton/ha) may cause improvement in corn forage yield.