4D phenotyping of germinating seeds and seedlings as a tool to objectively measure seed quality and improve field establishment and yield of sugar beets

摘要

The plant breeding company Strube, in cooperation with the German Fraunhofer Institute for non-destructive testing, has developed an automated high-throughput germination test for sugar beet seeds. The phenoTest permits objective measurement and classification of germinating seeds and resulting seedlings. It is therefore more accurate and provides more information than the conventional ISTA (International Seed Testing Association)-germination test, which relies purely on visual assessment and classification into the categories "normal" or "abnormal". This differentiation is difficult to standardise, and is, to a significant degree, subjective. The phenoTest is based on three-dimensional (3D) X-ray images. Repeated tests of the same plants enable an objective assessment of seedling development over the course of time (4D phenotyping). The individual organs of each plant (radicle, hypocotyl and cotyledons) are automatically identified and measured. The method provides detailed information on germinating capacity and vigour, as well as the homogeneity of a seed lot. Results are documented as measurement values and 3D-images of each individual plant at different time points. The data is used to compare seed lots concerning their natural germination capacity and especially vigour, the processing or priming technologies they experienced, the pelleting and seed treatment applied etc. in order to predict their field emergence potential even under difficult growing conditions. These analyses also helps to optimise all these processes in commercial seed production to obtain a quick, homogeneous and complete field emergence, making full use of the genetic yield potential of sugar beet.