![\"\"](\"https:\/\/www.ypaithros.gr\/en\/wp-content\/uploads\/sites\/2\/2024\/10\/KALLISTH-LOGO-FINAL-EN-01-1.png\"){kind=logo}
<\/p>\nIn conventional crop fertilisation, fertiliser is uniformly applied in the field, with the amount of fertiliser usually determined based on the yield of the sections with the lowest yield. Fertile sections of the field often receive more fertiliser than required, and each field receives the same amounts of fertiliser for the same crop each year, regardless of the weather conditions and when it is applied. All of the above contribute to reduced uptake of the applied fertiliser by crops, which can go as low as 30%, with very significant economic and environmental repercussions.<\/p>\n
<\/p>\n
In recent years, the Institute of Industrial and Forage Crops \u2013 in collaboration with the Goulandris Natural History Museum and researcher Dr. Stamatis Stamatiadis \u2013 has been studying variable nitrogen supply to fields through multiple field experiments under real conditions, in order to increase the efficiency of nitrogen fertilisation. In collaboration with Dr. James Schepers, professor at the University of Nebraska in the USA, active multispectral foliar sensors were used to identify plants\u2019 different nitrogen needs and apply appropriate fertiliser doses depending on actual plant needs, which vary both spatially within the same field and over time from year to year.<\/p>\n
The active multispectral foliage sensors produce adjustable radiation in the visible (VIS, 400-700-nm) and infrared (NIR, 700-1,000-nm) electromagnetic spectrum ranges. They generate their own radiation in a way that makes it completely discernible from natural light, enabling them to be used at any time during the day (even during the night) and in any lighting conditions (clouds, fog, etc.).
\nPart of the radiation emitted by the sensors is absorbed by the foliage of the crop, and the rest is reflected. The radiation reflected by the foliage of the crop can be measured and quantified into various indicators. After many years of experiments in the USA, in 2010 Dr. Schepers\u2019 research team created an algorithm that converts the reflectance measurements of the corn foliage carried out by active sensors into nitrogen fertilisation doses relative to soilological and other data. The amount of nitrogen calculated by the algorithms for a specific point in the field depends not only on foliar reflection indices, such as the NDVI chlorophyll index, but also on the stage of development of the crop at that point in time, the total amount of nitrogen required by the crop, and the amount of nitrogen already applied.<\/p>\n
In this way, the information for assessing the nitrogen requirements is not based on soil analyses or plant tissue analyses, but on the reaction of the plant itself to the incident radiation, which includes any differentiations both spatially within a field and year to year. An important advantage of the method is that the behaviour of the plant in absorbing\/reflecting the radiation received from the sensors incorporates all soil and climatic factors that affect its final yield.<\/p>\n
Initially, from 2010 to 2012, the new surface nitrogen fertilisation method was used in cotton cultivation in the \u201cHydroSense\u201d project, which was co-funded by the European Commission through the LIFE+ environment programme. In HydroSense, prior to sowing, Management Zones (MZs) were created in the fields, using the multispectral sensors that map the reflection of the near-infrared spectrum of the bare ground. Surface nitrogen fertilisation was applied to each MZ in a differentiated manner, using the algorithm generated by Dr Schepers\u2019 research team to estimate the optimal dose. The nitrogen reduction achieved was on average 35%, without reducing the final yields on the six pilot fields of the project, while the nitrogen fertilisation efficiency, compared to conventional, increased from 65% to 98%.<\/p>\n
![](\"https:\/\/www.ypaithros.gr\/wp-content\/uploads\/2024\/11\/kalampoki_6_shutterstock_1548517592.jpg\")
<\/p>\n![\"\"](\"https:\/\/www.ypaithros.gr\/en\/wp-content\/uploads\/sites\/2\/2024\/10\/eip-agri-logo.png\"){kind=logo}
The Goulandris Natural History Museum, ELGO-DIMITRA\u2019s Institute of Industrial and Forage Crops, the \u2018THESGI\u2019 Farmers\u2019 Cooperative of Thessaly, GAIA EPICHEIREIN, and PRO DEPOT participated in the project. More information about the KAL.LI.S.TI project is available at: https:\/\/kallisti-og.gr\/<\/p>\n![\"\"](\"https:\/\/www.ypaithros.gr\/en\/wp-content\/uploads\/sites\/2\/2024\/10\/fasa-eng.png\")
<\/p>\n","protected":false},"excerpt":{"rendered":"