The preservation of plant biodiversity of Bulgarian flora is the main priority in scientific activities of IPGR – Sadovo. It is a part of the National Programme on Plant Genetic resources (PGR). Plant accessions in the base collections are evaluated according to the standards of FAO and European programme for PGR. The scientific programme for conservation of germplasm under controlled conditions in the gene bank is prepared according to the FAO requirements. The national collection of PGR in Sadovo includes crops and crop wild relatives- new varieties, selection lines, old varieties, local populations, mutants and wild species. The collection is divided into 7 main groups: cereals, grain legumes, industrial crops, vegetable crops, forage crops and medical and ornamental plants. The scientific work is carried out in 6 directions: enrichment with new geneplasm; evaluation of PGR; maintenance of PGR; conservation of PGR; documentation of PGR; use of PGR.