The objective of this study was to compare two populations of Crioula alfalfa cultivars, selected by the length of the seedling second internode (Crioula-LI, long internode = 2.5 cm; Crioula-SI, short internode = 1.5 cm) with Alfagraze cultivar in order to verify the seedling morphology value for the selection of more prostrate plants. The plants were grown individually in pots in a semi-protected environment and harvested at 74, 104, 134, 164, 194 and 224 days. Crioula populations varied in terms of height, leaf area, root volume, dry matter yield, and the Crioula-LI population outnumbered that of Crioula-SI. For height, length of internode and primary stem, Alfagraze (45.1 cm, 2.1 cm and 16.7 cm) was similar to Crioula-SI (37.6 cm, 2.3 cm and 18.2 cm); however, the leaf area (2.028 cm²) and dry matter yield (20.3 g) did not differ from those of Crioula-LI (2.021 cm², 21 g). The Alfagraze cultivar surpassed the Crioula population in terms of procumbency, crown diameter and crown stem number. At the flowering stage, the Crioula-LI cultivar had total stem number (61/plant) higher than Alfagraze (47/plant) and Crioula-SI (41/plant) cultivars. The length of the seedling internode is a promising marker for the selection of alfalfa, being a predictive factor for plant height, stem number, root volume and leaf area, and can be useful in the alfalfa breeding.
breeding; grazing-type; hay-type; internode