Opportunities for improved fertilizer nitrogen management in production of arable crops in eastern Canada: A review

Abstract

There is increasing public pressure to reduce the environmental impacts of agricultural production. Therefore, one key challenge to producers is to manage their crop production systems in order to minimize losses of nitrogen to air or water, while achieving crop yield and quality goals. Many strategies have been developed in recent years to meet this challenge. These include: development of new tools to measure crop N status in order to refine in-season fertilizer N management, development of new soil N tests to improve prediction of soil N supply, development of new fertilizer N products with release patterns more closely matched to crop N uptake patterns, and development of site-specific N management strategies. We review the opportunities and limitations to these new strategies within different arable crop production systems under the humid and sub-humid soil moisture regimes present in eastern Canada. Future research opportunities to improve the efficiency of fertilizer N utilization include development of practical methods to predict the magnitude of soil N mineralization; refinement of decision-making processes which take into consideration the crop N status and soil properties as a basis for variable rate fertilizer N application; development of affordable controlled-release fertilizer N products with improved N release characteristics; development of practical methods for capturing and recycling nutrient-laden drainage water; development of gene expression profiling based techniques to identify crop N stress; and application of crop genomics and molecular breeding techniques to accelerate the development of new cultivars with increased N use efficiency. Key words: Soil N tests, plant N tests, nitrogen fertilizers, nitrogen cycling

Nitrogen uptake by winter wheat (Triticum aestivumL.) depending on fertilizer application

“…However, the use of these fertilizers is substantially limited by their higher cost (Zebarth et al 2009). …”

Effect of Tillage Practices and Rice Straw Management on Soil Environment and Carbon Dioxide Emission

“…Therefore, emission of CO 2 in the present study is assumed to be somewhat higher which is attributed by subtropical climatic condition favoring faster microbial decomposition of soil organic matter. Emission of CO 2 was reported higher in warmer weather which vary with soil pH, moisture content, O 2 supply and N availability as all these factors have profound effect on soil microbial dynamics and activity (Zebarth et al, 2009). …”

Dry matter accumulation and potato productivity with green manure

“…Additionally, the total dry matter of potato accumulated by photosynthesis is utilized in different parts of the plant according to its development stage (Singh et al, 2008). However, each variety requires proper management of nitrogen fertilization (Brazinskiene et al, 2014), which makes it necessary to use correct doses of this nutrient for potato (Zebarth et al, 2009). The objective of this study was to evaluate the accumulation of dry matter, nitrogen and the productivity of potato with different quantities of sunn hemp, Crotalaria juncea L as nitrogen source.…”