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Nitrogen deficiency detection and fertiliser variable rate application in
cereals using remote sensing technology
Jana Galambošová, Vladimír Rataj, Matej Zemko
Department of Machines and Production Systems, Slovak University of Agriculture in Nitra,
Tr. A. Hlinku 2, 94976 Nitra , Slovak Republic
Nitrogen deficiency in cereals is characterized by leaf chlorosis, reduced net assimilation and
relative growth rates, lower leaf area, phytomass and grain yield. Over-application can lead to
the lodging of the crop and negative environmental impact, e.g. leaching or diffuse pollution
of excess nitrogen. As Nitrogen in crops varies, there is need to apply Nitrogen as soon as the
level of deficiency was estimated. Remote sensing technology uses the information on
spectral reflectance of crop. Data obtained are highly correlated with crop parameters and
enable to determine the level of nitrogen deficiency. Benefit of this technology is, that the
information can be gathered and used quickly. When combining this information with
information on position (x, y), the crop requirements can be met site specific.
Due to their availability the use of remote sensing sensors is most spread in Europe. These
are mounted on machinery and scan the crop. The information is evaluated and based on crop,
particular variety and growth stage the Nitrogen dose can be applied within one machine pass,
or later. As the results showed, this Nitrogen management technology brings benefits in two
areas:
a) the amount of Nitrogen applied may be reduced without a negative effect on yield,
b) the spatial redistribution of Nitrogen doses targets the site specific Nitrogen requirements
of crop. When using these sensors, the variability of applied doses was significant, what has
high potential advantages in terms of environment protection.
Acknowledgement: This paper was prepared in the frame of research project funded from the
European Union under the title: ITEPAg: Application of information technologies to increase
the environmental and economical efficiency of production agro-system, ITSM 26220220014.
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