Old landraces and obsolete cultivars represent a national heritage that must be conserved for future generations. Similarly, crop wild relatives (CWR) are a valuable gene pool for plant breeding or for direct introduction as a new crop. These materials have been mapped, collected, evaluated, regenerated, and conserved in the Gene Bank. In total, 3726 seed and vegetative samples have been collected in the Czech Republic, as well as 1582 abroad (in Slovakia, Poland and Austria) during cross-border cooperation projects. All collecting sites (over 1000) were located by GPS and plotted using the Geobaze Professional 2.8 mapping software. Altogether, 688 samples were declared as a national collection, and 627 seed accessions were conserved in the Gene Bank. In addition, 842 accessions of fruits were recommended for in situ conservation. Selected species of the families Poaceae, Fabaceae, and Alliaceae, which are rare or threatened in the Czech Republic, have been monitored in situ for 3-5 years. Two sites were suggested for protection as new protected areas.

In former Czechoslovakia, grass breeding was located in the three distinct regions of Southern Bohemia and Northern Moravia during the 1920's; and later in Slovakia in the 1940's. This resulted in the development of 45 cultivars of 17 grass species which originated from local ecotypes and were named after the place of their breeding (e.g. Táborský, Větrovský, Rožnovský, and Levočský). Most of these historical cultivars were not preserved in any national germplasm collection, and the number of missing accessions amounted to 27 of the 34 deleted varieties. Using the findings about unpreserved materials of Czechoslovak origin in the European Central Crop Databases, as well as the EURISCO web catalogue, it was possible to repatriate 7 historical cultivars (Arrhenatherum elatius Větrovský, Festuca pratensis Větrovská, Festuca rubra Rožnovská, Lolium perenne Táborský, Phleum pratense Větrovský, Poa nemoralis Rožnovská, and Poa pratensis Levočská) from the gene banks of the neighbouring European countries. The accessions were regenerated, and their seed has been stored ex situ in the Gene Bank of the Crop Research Institute in Prague.

The genetic implications and economics of regenerating forage species in different environments was studied in a multi-site field experiment. Two accessions of perennial ryegrass (Lolium perenne L.) and two accessions of white clover (Trifolium repens L.) from germplasm collections of the United Kingdom (UK), Czech Republic, Norway, Portugal and Denmark were cloned and planted in regeneration plots, each comprising 49 plants, at sites in the UK, Denmark, Czech Republic and Portugal. Inflorescence emergence date and seed yield of each plant within the plot was measured. G × E effects were quantified. Inflorescences of accessions of both species emerged earlier but with a greater spread in Portugal than in the other countries. Plants also exhibited significant variation in inflorescence emergence which was generally less in L. perenne than in T. repens apart from in Portugal where variation in T. repens was less than in L. perenne. Plant survival of L. perenne in Portugal was less than at the other sites in contrast to T. repens where there were few differences in survival between sites. The proportion of plants contributing to seed yield varied between sites and accessions. In L. perenne, seed yield was greatest in Denmark and lowest in Portugal but for T. repens, seed yield was greatest in the UK and lowest in Denmark; however, accessions differed in their sensitivity to site of multiplication due to differential response of plants to environment. The cost of regeneration in Portugal was 50% of the other sites but cost per gram of seed produced was lowest in Denmark (for L. perenne) and in Portugal (for T. repens). Regeneration costs as well as the sensitivity of accessions of forage grasses and legumes to environment during regeneration are therefore important when appropriate sites for regeneration are being considered.

Genebank accessions stored as seed populations require periodic rejuvenation in order to maintain sufficient numbers of viable seeds. During rejuvenation the genetic composition of accessions may be altered for a variety of reasons, of which variation in pollination rates between plants is the least understood. In the present study, a paternity exclusion analysis was performed on a rejuvenated accession of perennial ryegrass. In addition, flowering data of the 49 parental plants were collected during the flowering season. The aim of the study was to determine how accurate variation in pollination rates between plants can be predicted from data on the spatial and temporal distribution of pollen release. The parental population and a total of 551 offspring from 12 progeny arrays were genotyped by means of molecular analysis. Using 25 microsatellites, paternity was identified for 81.9% of the offspring, while remaining ambiguities were resolved by AFLP analysis, except in four cases. Within the total sample 9 cases of contamination were observed. Mating within the study population was clearly non-random, as 61.9% of the identified pollen donors were located within 1 m distance from the mother plant. Observed pollination rates were very well described by an inverse quadratic function of inter-plant distance between potential mating pairs. Incorporation of the recorded flowering data in the calculation of expected pollination rates improved the goodness of fit with observed values by only 0.77%. Suggestions to reduce the variance in paternal contributions were presented. However, contamination was considered more threatening to the genetic integrity of perennial ryegrass germplasm than variation in pollination rates between plants, and indicated the need for improved measures to avoid gene flow from other germplasm.