Effects of different tillage methods on weed density and soil properties for winter wheat production in a clay-loam soil under dryland conditions

SUMMARYIn this research, the effects of the classic tillage method (CT) using themoldboard plow and as an alternative the surface tillage method (ST) using the tootharrow combination on some of the physical and chemical properties of the soil, weeddensity and yield are compared, in winter wheat production at the Çanakkale Region. Inaddition, the economical comparisons of the two methods used were made by analyzingtheir incomes and outcomes and finally, the most profitable method is determined.Compared to the classic tillage method, which is used in the surface tillagemethod increased soil bulk density which is used to determine the soil compaction,around 8% at the 15cm soil depth where the wheat roots are active. Merely, in bothmethods the bulk density values remained under the 1.60 g/cm3 value that is directlyeffective on plant development and thus yield (Hakansson and Lipiec, 1999). In additionto increasing soil porosity the surface tillage method was more effective compared to theclassic tillage method in conserving the soil properties. There wasn?t any statisticaldifference in the soil penetration resistance measurements however, especially at the soildepths beyond the 30cm s it was seen that the penetration resistance values for theclassic tillage method were bigger than the surface tillage method.It was observed that there were no differences between the two methods interms of plant development. Grain yield for the classic tillage method was 5509 kg/ha,while it was 4376 kg/ha for the surface tillage method.When the total cost and outcome/income rates determined by taking the processnumbers and machine usage into concern were examined it is determined that the totalcost per area was 650.79 $/ha in the classic tillage method and 614.03 $/ha in the surfacetillage method. When the outcome/income rates were measured by taking the totalwheat yield into consideration, it was seen that the classic tillage method was moreprofitable with the 2.36 rate compared to the surface tillage method (1.99).It has come to the conclusion that the surface tillage method which conservesthe soil properties and weed density was high is applicable for wheat production as analternative method compared to the classic tillage method where the moldboard plow isused for wheat production.It is possible to say that reduced soil tillage methods and soil tillage applicationsconserving the soil properties is inevitable in the sustainable agriculture systems andespecially that it may be among applications to prevent the energy problem which hasbeen an issue recently and is foreseen to be a much more important problem in thefuture.