Bladgødskning af sukkerroer med kvælstof
Konklusion
I begge år blev der opnået tilsvarende sukkerudbytter ved at erstatte 25% af den tildelte kvælstofmængde med kvælstof via bladgødskning. Der var dog tale om ikke-signifikante merudbytter for kvælstoftildeling i 2024 og der er derfor brug for flere forsøg, for generelt at kunne konkludere om kvælstofudnyttelsen ved bladgødskning.
I begge år blev yderligere en variant af bladgødning afprøvet. I begge tilfælde sås udbyttetab i forhold til en kvælstofstrategi baseret på 60 kg N per ha placeret + 2 x 10 kg N per ha via bladgødskning.
Supplerende forsøg i 2024 indikerer, at bladgødskning bør opstartes tidligere (maj-juni) end i ovennævnte forsøg (juni-juli).
I forsøget i 2024 indgik måling af lattergasemission. Der vil dog ikke blive draget nogen konklusioner før der foreligger flere forsøgsresultater fra kommende forsøg i 2025.
Conclusion
In both years similar sugar yields were obtained when 25% of the nitrogen was applied with leaf fertiliser. There was no significant effect of nitrogen fertilisers in 2024, and more trials are needed to generally conclude about N-effects using leaf applications.
In both years one additional variant of leaf applications was tested. In both cases, yield loss was observed compared to a strategy with 60 kg N per ha placed + 2 x 10 kg N per ha via leaf applications.
An additional trial in 2024 indicates that leaf applications must be initiated earlier (May-June) than in the above-mentioned trials (June-July).
In the trial in 2024, also emissions of nitrous oxide were measured. However, conclusions on this topic will not be made until further trials have been performed in 2025.