In maize hybrid development, gains in heterosis do not explain all the gain observed in grain yield across time. Non heterosis gains (measured as grain yield improvement of parental lines) have been also an important contribution. Improvement of maize inbred lines, therefore, is crucial for successful seed production but also because their improvement translate into superior hybrids. Knowledge on parent-progeny relationships (PPR) for physiological attributes (e.g. light capture, radiation use efficiency –RUE-, harvest index –HI-, kernel set per unit plant growth rate around silking –reproductive efficiency-) is very scarce. The objective of this research was to determine the described relationships for a set of twelve single-cross maize hybrids obtained from six inbred lines. Field experiments were conducted during three growing seasons, and included two contrasting nitrogen levels. Twenty morpho-physiological attributes were evaluated, and were classified in four different groups. The first group had low heterosis and high PPR, and included attributes usually used in breeding (time to silking, anthesis-silking interval, total leaf number). The second group had high PPR and significant (P<0.05) heterosis at all nitrogen levels, and included traits related to light capture, biomass production, plant growth rate and HI. These attributes could be included in a breeding program because of their relationship with grain yield determination. For the third group of traits (RUE and reproductive efficiency), inbreds did not predict the performance of their hybrids accurately. These traits should be improved in hybrids but not in inbreds. The forth group included traits with high PPR at high nitrogen availability but not at low soil nitrogen (N0), like kernel number and grain yield. For N0 type environments, improvement of these attributes in inbreds should be performed on those traits related to grain yield (e.g. plant growth rate at critical periods, biomass production, light capture, HI).