# Intra-Plot Variable N Fertilization in Winter Wheat through Machine Learning and Farmer Knowledge
## 3 Results and Discussion
### Variable Fertilizer Application Considerations and On-Farm Experimentation
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \multicolumn{6}{c}{**Variable N Application**} & \multicolumn{6}{c}{**Homogeneous N Application**} \\ \hline
**Zone** & **kg N ha\({}^{-1}\)** & **Area (ha)** & **kg N** & **Zone** & **kg N ha\({}^{-1}\)** & **Area (ha)** & **kg N** \\ \hline
1 & 55 & 3.37 & 185 & 1,2,3,4 & 110 & 12.23 & 1345 \\
2 & 88 & 2.95 & 259 & & & & \\
3 & 99 & 3.70 & 375 & & & & \\
4 & 110 & 2.21 & 244 & & & & \\ \hline  & & 12.23 & 1064 & & 12.23 & 1345 \\ \hline \end{tabular}
\end{table} 
Table 3: Dose of N applied in the plot with and without zoning. stances, practices, and needs, providing practical and contextualized information on how to use, adapt, and develop local innovations [56]. The adaptation of the technique used to the specific needs of the plot was a work carried out jointly with the farmer. Once the experimentation was concluded, the results obtained through this technique were visible to the farmer. After the knowledge is transferred, replication of the experiment is simple since the farmer now has both the resources and the knowledge [57]. For example, the close collaborative work between academics and the farmer carried out in this work encouraged the farmer to extend the use of the VRF to his entire farm, which consists of more than 70 plots and 200 ha. According to the farmer, the need-to-know GIS tools to edit fertilizer prescription maps constitute the bottleneck of the process. According to the farmer, if this step, which allows easy map editing, is not solved, widespread implementation of this technique would be extremely low or non-existent in our conditions. To try to solve this problem, the fertilizer prescription maps for the following season (2020-2021) were made using the remote sensing decision support tool implemented in the Agrogestor platform (www.agrogestor.es (22 September 2022)). The procedure to obtain a prescription map is as follows. Firstly, the farmer sets the plot and dates, then the platform provides maps of vegetative indices such as the NDVI. In the next step, the farmer must select the map that most closely resembles yield variability, and then the platform classifies the map into four zones using an unsupervised classification algorithm. Using this map, the Agrogestor platform allows users to easily create a fertilizer prescription map. The platform provides a classified map where the farmer allocates a fertilizer dose to each zone. The platform can export the prescription map to a spreader-friendly format. The farmer confirmed that the process of using the tool was easy and can help in the adoption of this technique. Another advantage of performing trials with the farmers is the added knowledge generated on the social level, through knowledge sharing and updating between both groups [58]. In addition, at the scientific level, analytical work through meta-analysis and integration of real data helps to better address real problems. The integration of innovative technologies in the agricultural sector could help solve the problem of an aging sector as many young people are not attracted to agriculture, considering it old-fashioned and obsolete [59]. The technicification of the agricultural sector through the acquisition of modern technologies may reverse this process by turning what is considered obsolete into something new. The recent development of online farming games can also help make agriculture more attractive, showing farming through technology that young people are comfortable with. The adoption of such technologies can help to reduce the technical, legislative, economic, and educational barriers that currently exist [60]. An economically, socially, and environmentally sustainable agri-food sector can help to repopulate rural areas, making them more attractive, lively, and dynamic, and paying special attention to the generation of wealth and the integration of young people and women [61].