EN
Fourteen F5- and F6-pedigrees previously selected for a more vigorous seminal root system in a cross population of spring barley, were compared with their parents in the response to severe post-sowing drought and limited N- and P-supply.The materials were studied in glass-faced soil boxes, sand-vermiculite cultures and in the field.The F5's juvenile rooting superiority was not totally preserved for further growth stages suggesting partly different genetic backgrounds responsible for the seminal root system at various growth stages.Results indicated an absence of close genetic correlations between the seminal and adventitious root systems.The selected spring barley pedigrees exibiting a more vigorous rooting benefit much more for their ability to avoid drought conditions than for their tolerance to nitrogen and phosphorus limitations.Especially under decreased N availability the enhanced root extension in F5s resulted in a depressed shoot dry matter production.Despite a relatively low differentiation in the grain yield, some of the selected F6-pedigrees were simultameously found to indicate a high yield potential, an improved stability or tolerance to low-input.