The introduction of a new crop requires adapted genotypes as well as optimum crop management practices. This study was conducted to determine the optimum crop density of adapted grain amaranth genotypes in the Pannonian region of Eastern Austria. The genotypes Neuer Typ (A. hypochondriacus), Mittlerer Typ (A. hypochondriacus) and Amar (A. cruentus) were established at plant densities of 8, 17 and 35 plants/m(2) in 2002 and 2003. Average hand-harvested yields ranged from 2200 to 3000 kg/ha without significant genotypic differences. Genotypes differed in thousand seed weight (0.55-1.04 g), time from sowing to harvest (97-130 days), grain water content at harvest (24-38%), microbial infestation of air-dried grain (0.2-118.6 cfu x 10(6)/g), germination (29-79%) and grain composition. Grain contents fell within the following ranges: crude protein 15.2-18.6%, crude fat 5.4-8.6%, crude fibre 3.5-4.2%, ash 2.7-3.2%, and carbohydrates 66.7-72.7%. High grain water contents involved stronger microbial infestation and reduced germination. Crop density affected neither grain yield nor grain quality.