عنوان مقاله [English]
Every year the degradation of agricultural soils are increasing due to improper tillage operations. The main objective of this study was evaluation and comparison of shallow and conventional tillage methods and their effects on wheat yield and its components. The study was conducted in three consecutive years with two treatments and four replications in Khosroshahr, Iran. Treatments was 1. conventional tillage method comprised of: moldboard plowing at the depth of 20-25 cm, disk harrowing at the depth of 12 –15 cm, leveling, following by chemical fertilizer and planting with grain drill, and 2. Shallow tillage method was included: disk harrowing in the depth of 6-8 cm after removing residue, disk harrowing in the depth of 12 –15 cm in fall, spike tooth harrowing, following by chemical fertilizer and planting with grain drill. The combined analysis of data indicated that there was no significant difference between conventional and surface tillage methods in grain yield, number of heads in unit area, number of grain in the head, 1000 kernel weight, weight of straw and harvesting index. The average wheat yield by conventional tillage was 79 kg more than that of by shallow tillage. This difference might be due to higher plowing depth and better residual burying with mold board plow. The grain yield in surface tillage was 97.5% of the yield in conventional tillage. Conventional tillage consumes more energy compared to shallow tillage, takes more time, causes more depreciation of the implements and therefore increases costs. Considering short available time for cultivation, and also no significant differences in the yield by the two tillage methods, the shallow tillage can be recommended in irrigated wheat farms.