n addition to the exact statistical analysis, a simple visual analysis can also be carried out by laypersons by simply observing. Differences in plant height, in the appearance of the plants, differences in colour and the death of plant parts (necroses) can indicate nutrient deficiency or too low pH values in the soil. In addition to differences in the height of the plants, typical symptoms may be observed:
Nitrogen (N) deficiency: yellow discolouration of older leaves or the whole plant (chlorosis)
Phosphorus (P) deficiency: purple discolouration (antocyanin discolouration) on stems (maize) and leaves (rape)
Potassium (K) deficiency: Unusually strongly upturned leaves in maize (stiffs growth habit), limp leaves during drought (lack of turgescence), death of leaf edges (leaf margin necroses)
Lack of liming: mixture of different symptoms, as many nutrients and soil properties are indirectly affected.
The trial was established in 2018 on a site with a sufficient supply of nutrients. In the first years after the trial was established, clear symptoms of nitrogen (N) deficiency are to be expected. In the following years, phosphorus (P) deficiency and potassium (K) deficiency are to be expected. Only with strongly decreasing pH values will the lack of liming become noticeable.
