Document Type : Research Paper
Abstract
The current study was conducted to compare the effect of different tillage methods on wheat yield of canola-wheat rotation in dryland areas during three years (2005-2008) north of Khouzestan (Baghmalek city). Randomized block design with five treatments was applied by using four replications. Canola tillage was done with conventional method and the experimental wheat treatments were: (1) moldboard plow + grain-drill, (2) chisel plow + grain-drill, (3) moldboard plow with removed moldboard + grain-drill, (4) sweep plow + grain-drill and (5) no-till-drill. The investigated indices were percent age of organic materials, soil moisture content (W.B), wheat yield and other agronomical factors. Complex variance analyses of the three years data showed no significant difference between tillage methods and interaction of tillage methods with year in case of soil moisture content in different plant growth stages. However, the effect of years was different for this factor. Analyses of variance for different tillage methods showed that there was no significant difference between percent age of organic materials in soil depths. The complex variance analyses of data also showed that tillage methods had a significant effect on harvesting index and biological yield but the difference in grain yield and other agronomical factors was not significant. In general, the tillage methods did not affect wheat yield. Hence, the conservation methods are recommended for this condition. Regarding the harvest index, the sweep plow with 43 percent had the highest and no-till-drill with 36 percent had the lowest amount. Moreover, in biological yield, the moldboard plow with 5263 and sweep plow with 3718 kg/ha had the most and the least values respectively.
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