Revisiting seedrow nitrogen placement with barley and wheat

2008 ◽  
Vol 88 (6) ◽  
pp. 1073-1086 ◽  
Author(s):  
R. E. Karamanos ◽  
J. T. Harapiak ◽  
N. A. Flore

The rates of nitrogen (N) that can be safely placed with the seed remains a frequent question of producers, especially as direct seeding continues to increase as a practice in western Canada. Guidelines have been in place since the mid-1990s; however, they address only "favourable conditions" and experimentation relating to their derivation has not been formally published. This study attempted to quantify "favourable conditions" as well as supplement existing guidelines with information under non-favourable or ideal conditions so that producers may assess the risk of applying N with the seed. To this end, the results from 32 experiments with CWRS wheat and 10 with barley conducted in early to mid-1990s were compiled. The experimental design included three seedbed utilization (SBU) rates (10, 20, and 40%) and five N rates (0, 20, 40, 60, and 80 kg N ha-1) with four replications. Grain yield, relative plant stands (calculated as a percentage of the unfertilized control) and days to maturity (DTM) were determined in all experiments. Three types of responses to seedrow N application occurred. Type A had no impact of fertilizer N rate on the yield of CWRS wheat at wide (40%) SBU, but grain yield decreased at narrower SBU (10 and 20%). Type B had no impact of fertilizer N rate on the yield of CWRS wheat at narrow (10%) SBU but grain yield increased at wide SBU (20 and 40%). Type C had grain yield increases due to fertilizer N independent of SBU. Type A was characterized by dry soil moisture conditions and relatively high residual NO3−-N levels, whereas Types B and C were characterized by normal and very moist soil conditions and low to medium residual NO3−-N levels. The results within each response type were modified by soil organic matter (SOM) and texture. Grain yield losses generally occurred when relative plants stands were below 85% of those of unfertilized plots. In addition, conditions that led to a decrease in relative plant stands and grain yield also resulted in delayed maturity. Accounting for all the above factors enabled us to expand current guidelines under normal conditions to a range of agroecological conditions. Key words: Guideline, texture, soil organic matter, residual NO3−-N, soil moisture

Proceedings ◽  
2019 ◽  
Vol 30 (1) ◽  
pp. 26
Author(s):  
Marqués ◽  
Bienes ◽  
Ruiz-Colmenero

The wine captures grapes’ variety nature and vinification techniques, but other aspects of soil, climate and terrain are equally important for the terroir expression as a whole. Soil supplies moisture, nitrogen, and minerals. Particularly nitrogen obtained through mineralization of soil organic matter and water uptake are crucial for grape yield, berry sugar, anthocyanin and tannin concentration, hence grape quality and vineyard profitability. Different climatic conditions, which are predicted for the future, can significantly modify this relationship between vines and soils. New climatic conditions under global warming predict higher temperatures, erratic and extreme rainfall events, and drought spells. These circumstances are particularly worrisome for typical thin soils of the Mediterranean environment. This study reports the effect of permanent grass cover in vineyards to maintain or increase soil organic matter and soil moisture. The influence of natural and simulated rainfalls on soils was studied. A comparison between minimum tillage (MT) and permanent grass cover crop (GC) of the temperate grass Brachypodium distachyon was done. Water infiltration, water holding capacity, organic carbon sequestration and protection from extreme events, were considered in a sloping vineyard located in the south of Madrid, Spain. The MT is the most widely used cultivation method in the area. The tradition supports this management practice to capture and preserve water in soils. It creates small depressions that accumulate water and eventually improves water infiltration. This effect was acknowledged in summer after recent MT cultivation; however, it was only short-lived as surface roughness declined after rainfalls. Especially, intense rainfall events left the surface of bare soil sealed. Consequently, the effects depend on the season of the year. In autumn, a rainy season of the year, MT failed to enhance infiltration. On the contrary, B. distachyon acted as a physical barrier, produced more infiltration (22% increase) and fewer particles detachment, due to increased soil structure stability and soil organic matter (50% increase). The GC efficiently protected soil from high-intensity events (more than 2 mm min-1). Besides, soil moisture at 35 cm depth was enhanced with GC (9% more than tillage). On average, soil moisture in GC was not significantly different from MT. These effects of GC on soil conditions created local micro-environmental conditions that can be considered advantageous as a climate change adaptation strategy, because they improved water balance, maintained a sustainable level of soil organic matter, therefore organic nitrogen, all these factors crucial for improving wine quality.


Weed Research ◽  
2019 ◽  
Vol 59 (6) ◽  
pp. 490-500
Author(s):  
W Kaczmarek‐Derda ◽  
M Helgheim ◽  
J Netland ◽  
H Riley ◽  
K Wærnhus ◽  
...  

1980 ◽  
Vol 60 (4) ◽  
pp. 599-611 ◽  
Author(s):  
V. A. DIRKS ◽  
E. F. BOLTON

Regression and covariance analysis of a 13-yr rotation experiment of corn on Brookston clay soil showed that grain yield of corn could be related to each of nine other plant and soil measurements. Soil compaction as measured by bulk density was negatively associated with the level of leaf K in the plants, as well as available soil moisture. The major part of the yield difference between fertilized continuous corn and fertilized corn following alfalfa could be accounted for by multiple regression of grain yield on leaf N and K nutrient levels, soil compaction and soil moisture. Soil compaction was not affected or modified by fertilizer treatment. Response of corn grain yield to soil conditions, moisture and plant nutrient level appears to vary with rotation and fertilizer input.


2003 ◽  
Vol 83 (1) ◽  
pp. 129-139 ◽  
Author(s):  
A. M. Johnston ◽  
G. P. Lafond ◽  
W. E. May ◽  
G. L. Hnatowich ◽  
G. E. Hultgreen

An understanding of the effects of different opener designs and on-row packing force would help producers in their selection of appropriate direct seeding implement options for their soil conditions. A field trial was conducted at three locations (Indian Head, Sylvania and Watrous) in Saskatchewan from 1997 to 1999 to evaluate the effect of opener-packer design (spoon-steel V packer; spoon-flat rubber packer; paired row-steel V packer; paired row-flat rubber packer; sweep-pneumatic tire) in combination with a range of on-row packing forces [0, 333, 549, 746, and 1000 Newton (N) per press wheel] on crop emergence and grain yield with direct seeding. The differences observed between opener-packer combinations in this study varied by less than 10% for grain yield, and were almost always associated with the opener design and not the packer type. Despite the variable results, there was a tendency for higher pea and wheat emergence with the sweep + tire compared with other opener types at those locations that tended to be drier in the spring. Also, grain yield tended to be greater for the sweep + tire in 1999 at Indian Head, when the heavy-textured soil at this site had high soil moisture conditions at seeding. The responses to packing force varied with different years and among the crops. Generally, 333 N per press wheel provided adequate emergence and grain yield across the environmental conditions encountered in this study, regardless of the opener-packer combination. In 1997, 5% more pea seedlings emerged with some amount of packing compared with no packing. Relative to the check, some packing resulted in wheat grain yield that was 13% greater at three of the location-by-year combinations, and wheat emergence that was 9% greater in 1998. However, with canola excessive packing force (i.e., the two highest vs. lower packing forces) resulted in 11 fewer seedlings m-2 in 1999. A packing pressure of 333 N per press wheel provided adequate emergence and grain yield across varied environmental conditions, with higher packing force only negatively influencing emergence in canola, and not yield. Key words: Furrow opener, packing force, emergence, direct seeding, zero till


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Leiyi Chen ◽  
Li Liu ◽  
Shuqi Qin ◽  
Guibiao Yang ◽  
Kai Fang ◽  
...  

Abstract The modification of soil organic matter (SOM) decomposition by plant carbon (C) input (priming effect) represents a critical biogeochemical process that controls soil C dynamics. However, the patterns and drivers of the priming effect remain hidden, especially over broad geographic scales under various climate and soil conditions. By combining systematic field and laboratory analyses based on multiple analytical and statistical approaches, we explore the determinants of priming intensity along a 2200 km grassland transect on the Tibetan Plateau. Our results show that SOM stability characterized by chemical recalcitrance and physico-chemical protection explains more variance in the priming effect than plant, soil and microbial properties. High priming intensity (up to 137% of basal respiration) is associated with complex SOM chemical structures and low mineral-organic associations. The dependence of priming effect on SOM stabilization mechanisms should be considered in Earth System Models to accurately predict soil C dynamics under changing environments.


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