The Effect of Some Nitrogen Fertilization Practices and Tillage Systems on Growth and Yield of Wheat Crop within The Conditions of The Sedimentary Plain in Iraq

Abstract

. This study was carried out in the Faculty of Agriculture in Abu Ghraib in silty loam texture soil classified as Typic Torrifluvents, as a factorial experiment in split-split plot designs with four replicates. Tillage treatment input in the main blocks, By dividing the field into three sections, the first was left without a tillage (T0), the second was plowed a surface plowing to a depth of 12 cm (T1), while the last section of the field plowed with moldboard plow was used at operating depth of 25 cm (T2). The Nitrogen fertilization was added as the following: Ground addition (N1) included the addition of 125 Kg N ha-1 in two batches were added, first at the second irrigation after germination the wheat crop Ibaa 99 variety (broadcasting) and the second batch at the stage of expulsion of spikes, while the second treatment (N2) was foliar applied on the plant with the same amount above, as well as the third treatment (untreated control) no-Nitrogen fertilizer added (N0).At the end of the experiment after harvesting the following characteristics were studied: plant length, number of strokes, vegetative system weight, grain yield, weight of 1000 grains. Soil bulk density and the Mean weighted diameter of soil aggregate's for depths of 5-0, 10-5, 20-10, 30-20, and 30-40cm, and we measured the mean weighted diameter and volumetric distribution of soil aggregates by dry sieving method, also the water infiltration.The results showed that the tillage method had significant effect on the soil bulk density values of the soil after preparing the land for cultivation. Also, there were significant differences between tillage treatments in this property values after harvesting. While there was a significant effect of nitrogen fertilization in increasing the soil mean weighted diameter values as affected by tillage when compared with the control treatment (without nitrogen addition), the Nitrogen fertilization resulted a significant increase in the studied wheat crop growth indicators in both tillage treatments T1 and T2. Within two the Nitrogen addition methods N1 and N2 compared to the control treatment for both treatments. In addition, there was a significant effect for interaction for the two studied treatments on the overlap of both factors in the studied growth indicators. Also Nitrogen fertilization had a significant effect on wheat yield content (seed yield, 1000 grain weight and protein content in grains) due to reduce tillage and nitrogen fertilization was reflected in the increase of yield.