Heritability and genotypic and environmental correlations of creeping root and persistency in Medicago sativa L.

Abstract

This study examines the relationships between creeping-rootedness, plant diameters, and persistency in lucerne. Highly significant positive genetic correlations were found between all three plant characters among families under continuous grazing. The investigations disclosed several trends in genetic and environmental correlations, the significance of which is discussed. The heritabilities for the proportion I of creeping plants (0.41), plant diameter (0.32–0.45), and survival (0.23–0.46) were all high, indicating that response to selection is possible. The results showed that plant density decreased under continuous grazing; 66% of the creeping-rooted plants but only 8% of Hunter River plants survived after 17 months of continuous grazing.