To access the documents hosted by OpenAgrar no registration is necessary.
Open Agrar is the publication server of the federal research institutes within the portfolio of the German Federal Ministry of Food and Agriculture (BMEL). It provides access to the research output of six research institutes (Deutsches Biomasseforschungszentrum, Julius Kühn Institute, Friedrich-Loeffler-Institute, Max Rubner-Institute, Johann Heinrich von Thünen Institute and German Federal Institute for Risk Assessment).
We are actually only hosting publications from authors working in one of the institutes mentioned above and publications out of Journals, Conference Proceedings etc. edited and released by the institutes.
If you work in one of the institutions and want to submit or register your publications by yourself, a registration is necessary. Please contact the library of your institution. You will find the address under Contact.