The current study deals with genetic improvement of the nutritive value of forage maize . In separate field trials, maize inbred lines without the brown midrib trait and derived hybrids were evaluated for stalk quality as well as some other agronomic traits . The aim was to relate the performance of lines and hybrids . Quality traits studied were the contents of ash and cell walls expressed as percentage of dry matter and the digestibilities of organic matter and cell walls (stalk-dv% and stalk-dcw%, respectively) . The performance of hybrids was established in a trial at two locations with three replicates per location and the performance of lines at one location in an unreplicated trial .The range for stalk-dcw% was about 10 percentage units between hybrids and 15 percentage units between inbred lines . Stalk-dcw% had of all quality traits of hybrids the highest broad-sense heritability (h 2 = 0.74), and determined about 80% of the variation in stalk-dv% . The only stalk quality trait where a significant correlation was found between the mean hybrid performance and the corresponding midparent value was stalkdcw% (r= 0 .70, P< 0 .01) .In conclusion, stalk-dcw% proved to be the only stalk quality trait worth evaluating at the inbred line level in a breeding programme aimed at producing commercial hybrid varieties of forage maize.

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