Effect of Different Tillage Methods on Grain Yield and Yield Components of Corn in the Arid Lands of Iran
Field experiments were conducted to study the effect of different tillage methods on grain yield and yield components of corn (Zea mays L.) in the arid lands of Iran. Tillage treatments in the study were moldboard plow + two passes of disk harrow (MDD), moldboard plow + one pass of rotary tiller (MR), two passes of disk harrow (DD), one pass of tine cultivator + one pass of disk harrow (CD), one pass of rotary tiller (R), one pass of tine cultivator (C) and no-tillage (NT) as direct drilling method. The statistical results of the study indicated that tillage method significantly (P = 0.05) affected grain yield, number of plants per hectare (NPPH) and number of rows per ear (NRPE), but there was no significant difference in other components such as number of ears per plant (NEPP), number of grains per row (NGPR), ear diameter (ED) and ear length (EL). The maximum value of grain yield (4.15 t ha ), NPPH (39830) and NEPP (0.92) was obtained in case of MDD treatment, while maximum 1 value of NRPE (14.9) and ED (37.2 mm) was observed in case of MR treatment. Also, maximum value of NGPR (51) was obtained in case of R treatment, while maximum value of EL (196.3 mm) was observed in case of NT treatment. Conversely, the minimum value of grain yield (2.32 t ha ) and NPPH (20390) was obtained in case 1 of NT treatment, while minimum value of NEPP (0.89) was observed in case of C treatment. Moreover, minimum value of NRPE (13.4) was obtained in case of R treatment, while minimum value of NGPR (47), ED (35.2 mm) and EL (190.7 mm) was noted in case of MDD treatment. Hence, moldboard plow followed two passes of disk harrow was found to be more appropriate and profitable tillage method in improving grain yield of corn possibly due to reduced soil compaction, enhanced seed-soil contact, increased soil moisture and suppressing weed growth.