A. R. Vaezi, S. Rezaeipour, M. Babaakbari,
Volume 23, Issue 3 (Fall 2019)
Abstract
Limited information is available on the effect of residues rates and slope direction on dryland wheat
(Triticum aestivum L.) yield. This study was carried out to determine the effects of residues rates and tillage direction on grain yield and yield components of the Sardary wheat in a dryland region in Zanjan. Five wheat residues rates (0, 25, 50, 75 and 100% surface cover) were applied and incorporated into soil in two slope directions (along the slope and on contour lines) using the randomized complete blocks design with three replications in a land with 10% slope steepness. Overall, thirty plots with 2m × 5 m dimensions were installed in the field and wheat grain yield and yield components were determined for growth period from 2015-2016. Results indicated that grain yield and yield components were significantly affected by the residues rates and slope direction and their interaction. In contour tilled plots, wheat grain yield (1.78 to per hectare), thousand grain weight (42.26 kg) and wheat height (55.11 cm) were 5.32, 5.01, 16.19 and 1.36 percent more than the plots tilled along the slope. The highest grain yield was found in 75% of residue (2.45 ton per hectare) under contour line direction which was about 53% bigger than control treatment (0% straw mulch) under along the slope. This study indicated that the application of straw mulch before cultivation and incorporating into soil using contour line tillage are proper soil management methods to obtain higher wheat yield in this dryland region.
A.r. Vaezi, S. Rezaeipour, M. Babaakbari, F. Azarifam,
Volume 27, Issue 3 (Fall 2023)
Abstract
Improving soil physical properties and increasing water retention in the soil are management strategies in soil and water conservation and enhancing crop yield in rainfed lands. This study was conducted to investigate the role of tillage direction and wheat stubble mulch level in improving soil physical properties in rainfed land in Zanjan province. A field experiment was done at two tillage directions: up to the downslope and contour line, and five stubble mulch levels: zero, 25, 50, 75, and 100% of land cover equal to 6 tons per hectare. A total of 30 plots (2 m×5 m) were created. The results indicated that water infiltration and water content were considerably affected by tillage direction, whereas its effect on water holding capacity was not significant. This physical property of the soil was influenced by the inherent properties of the soil, including particle size distribution. The change of up to down tillage direction to the contour line increased soil infiltration to 11% and water content to 6%. The physical soil properties were wholly influenced by mulch consumption. Soil water content increased in mulch treatments along with water holding capacity and infiltration rate. The highest volumetric water content was at 100% mulch level (10.62%) which was 11% more than the control treatment. However, there was no significant difference between 100% and 75% mulch treatment. This revealed that the application of 75% stubble mulch in contouring tillage is a substantial strategy for improving soil physical properties and controlling water loss in rainfed lands of semi-arid regions.
