Inheritance of Leaflet Size and Specific Leaf Weight in Alfalfa 1

The combining abilities for leaflet size and specific leaf weight (SLW) were determined at two different stages of growth in a 7 ✕ 7 diallel cross population of alfalfa (Medicago sativa L.). Both characters were heritable since the general combining ability was larger than either the specific combining ability or the reciprocal effects. Greater genetic variance was observed at an early bud stage than at a late bloom stage. Large differences in SLW were obtained only at an early bud stage. Leaflet size and SLW were not correlated. Genotypes that combined larger leaflet size and higher SLW were identified. Thus both traits would respond to selection in a plant breeding program. The correlation of these characters with forage yield was generally poor.