Effects of different irrigation levels on yield and yield components of sweet corn (Zea mays var. saccharata) using seedling cultivation under the plastic mulch

To evaluate the yield and yield components of sweet corn under the influence of different irrigation levels using seedling cultivation under plastic mulch, a split plot experiment was carried in a randomized complete block design with three replications at research field of Faculty of Agriculture, Yasouj University, in 2015. The main factor was irrigation in three levels based on the plant water requirement, 100% (I1), 75% (I2) and 50% (I3), and the sub-factor was the cultivation methods of sweet corn in six levels including seed cultivation under plastic mulch at April 4, (C1), seedling cultivation under plastic mulch at April 4 (C2), seed cultivation as conventional method at May 5 (C3), seed cultivation under plastic mulch at May 5 (C4), seedling cultivation under plastic mulch at May 5 (C5) and seedling cultivation as conventional method at May 5 (C6). The average air temperature on April 4 was 13.5 oC and on May 4 it was 16 oC. The results indicated that the interaction of irrigation × cultivation methods on ear yield at 5% probability level and on canned grain yield and economic water use efficiency at 1% probability level were significant. The highest ear yield was obtained from I2CT1, I1C1, I2C2 and I1C2 with 14420, 14414.4, 13691.7 and 13513.5 kg.ha-1, respectively. The use of seedling reduced water consumption and accelerated plant growth and development. The highest economic water use efficiency was observed in I2C2, I2C1, I3C2 and I3C1 with 2.21, 2.18, 2.16 and 2.14 kg.m-3, respectively. Totally, The results of this study showed that the use of 75% plant water requirement together with drip tape irrigation under plastic mulch is suitable for producing the maximum yield.