Galactose-binding lectin. Agglutinates human erythrocytes, and requires Ca(2+) and Mn(2+) ions for full agglutinating activity. Has antifungal activity against Fusarium sp., A.niger and A.flavus. Tetramer consisting of heterodimers of alpha and beta chains. Appears during seed development and remains in mature seeds. Belongs to the leguminous lectin family.