Fraunhofer Institute for Molecular Biology and Applied Ecology IME
Multipurpose seed coating to safeguard and increase crop yields by protecting and nourishing the seedling.
In times of climate change and limited use of crop protection products, the demands on farmers are increasing, both in organic and conventional agriculture. An important aspect in the transition of plant cultivation are new approaches in seed coatings in order to support early plant development, a very crucial phase for later crop yield.
To provide the crop an advantage over competing weeds, active components in seed formulations are increasingly important. In addition to structural components, e.g. binders or fillers, protective agents like pesticides and repellents, nutrients, as well as germination and growth stimulants, symbiotic soil microbes and soil conditioners (water absorbers) are being integrated in seed coatings. Even though the integration of chemical pesticides in seed coating has reduced their use during cultivation, further rethinking is required here as well. The alternative to synthetic components lies primarily in the use of natural (biological) starting materials. However, their integration in a coating and effectiveness in the field must first be established and proven on a crop-specific basis.
In the development of new and multifunctional seed coatings, the influences of individual components on the respective seed are tested in different formulations at Fraunhofer IME. In a first sorting step of the starting materials, material compatibility, process compatibility and mechanical compatibility of coatings with the respective seeds are investigated. The compatibility of the seed is evaluated on the basis of its germination capacity over time and under standardized conditions. This sorting step initially results in the basic suitability of a formulation as a binder or filler or as an active substance in a multifunctional coating. Further evaluation of the formulations is carried out in variations and combinations of the coatings compared to bare seed with regard to improved performance of the crop. Together with our partners crop-specific adaptations and functional enhancements are made at this stage via additives in the respective formulation or through changes in the structural makeup. The performance of the seed and the crop can be investigated via various parameters in the greenhouse and under field conditions. For functional evaluation, the seed's absorption behavior of various harmful substances and of water, the seedling's early development under limited water supply, the biomass development after field emergence of the crop, as well as the seed's storability and its compatibility with common sowing techniques are among the parameters analyzed.