At the Julius Kühn Institute for Grapevine Breeding at the Geilweilerhof in Siebeldingen (Südliche Weinstraße district), agricultural biologist Anna Kicherer is testing the 'Phenoliner': here, the devices of a grape harvester have been replaced by optical devices and a geo-information system. Hardly any daylight penetrates the tunnel inside the vehicle. Artificial light sources ensure that the difficulties caused by changing light conditions and changing backgrounds outside can be avoided during measurement. In addition to the broadband light sources, various sensors (RGB, NIR camera system, GPS and position sensors) are housed in the vehicle so that the 'Phenoliner' can record high-quality data with precise location information under standard conditions without external interference. This allows a lot of information on the phenotype of the grapes to be collected without having to test them destructively in the laboratory.

Until now, phenotyping has been very time-consuming and labor-intensive. People simply estimated the phenotypic data visually, a process that is subjective and prone to error. Today's sensors make it possible to record plant characteristics in a non-destructive way and to make reliable and objective measurements.

"We see the 'Phenoliner' as a test platform with the long-term vision that winemakers will also be able to use it," says Kicherer. The assessment of grapes as small, large or medium could become much more objective with this image-based technology. In grapevine breeding, such information is of crucial importance in order to be able to assess the special features of new varieties. "When it comes to developing genetic markers, you have to bring phenotype and genotype together," says Kicherer. This means that the external appearance must be traced back to the respective genetic make-up.

The 'phenoliner' is just one of several examples of possible efficiency increases through digital technologies in viticulture, says Ernst Büscher from the German Wine Institute: "Already today, only the healthy grape berries can be sorted out after the harvest using optical systems." In the near future, it will also be possible to use drones to protect plants on steep slopes that are difficult to access.