Experiments and simulation studies on the system Lolium perenne/Tylenchorhynchus dubius / A.L. den ToomGenetic, cytological and physiological aspects of seed yield in perennial ryegrass (Lolium Perenne L.) / Anjo ElgersmaProtoplast fusion for intraspecific transfer of cytoplasmic male sterility in perennial ryegrass / Jantina Creemers-MolenaarOn the relation between tillering, leaf area dynamics and growth of perennial ryegrass (Lolium perenne L.) / E.N. van LooTowards in vitro fertilization, gametosomatic cybridization and DNA transfer in perennial ryegrass (Lolium perenne L.) / Heleen M. van der MaasYield and respiration of populations of Lolium perenne as affected by plant growth conditions / Edwin KrausModelling interactions in grass-clover mixtures / Mehdi Nassiri MahallatiElevated atmospheric carbon dioxide and carbon dynamics in a grassland soil / Jan Hendrik van Ginkel