N-Tester
The N-Tester® works by optically measuring the chlorophyll content of leaves, which is strongly correlated with the plant's state of nitrogen nutrition. Thirty measurements repeated several times in the plot will give a representative average for the plot, and will help determine whether or not the crop requires additional inputs. The N-Tester® value is strongly influenced by growth stage and variety. Climatic conditions and crop biomass also influence the index measured.
Access the tool
| Name in original language | N-Tester |
| Name in English | N-Tester |
| Designer/ manufacturer | YARA - ARVALIS |
| Accessibility | Free |
| Weblink | https://www.yara.fr/fertilisation/outils-et-services/n-tester/ |
| Countries of primary use | France, Germany, United Kingdom |
| Main language | French |
| Other languages available | English, German |
| Brief description of the tool | The N-Tester® works by optically measuring the chlorophyll content of leaves, which is strongly correlated with the plant's state of nitrogen nutrition. Thirty measurements repeated several times in the plot will give a representative average for the plot, and will help determine whether or not the crop requires additional inputs. The N-Tester® value is strongly influenced by growth stage and variety. Climatic conditions and crop biomass also influence the index measured. |
| Target user | Tool/product manufacturer |
| Target crops | Barley, Wheat |
| Type of tool | Crop analysis |
| The tool assesses or provides guidance on | SPAD, Leaf nutrient content |
| Nutrients assessed | Nitrogen (N) |
| Nutrients assessed in the lab | Not included |
| The tool relies on a base recommendation system | Yes |
| Base recommendation system | Balance sheet forecasting method for N, in accordance with the equations defined by the COMIFER. |
| The assessment frequency should be | Once per week during set growth stages |
| Required data input is | Crop, Variety, Farm location, Nutrient input, Growth stage |
| The data can be imported from other tools and systems | No |
| The tools main output format is | PDF file |
| Data can be exported | No |
Funded by the European Union and UK Research and Innovation (UKRI). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union, European Commission or UKRI. Neither the European Union, European Commission nor UKRI can be held responsible for them.
Project Coordinators
Sarah Kendall
sarah.kendall@adas.co.ukSpyros Fountas
sfountas@aua.grheurope.nutrichecknet@gmail.com
Project Partners
