Effect of Defoliation at Flag Leaf Stage and Time of Anthesis on the Yield of Sorghum

Removal of leaves of field-grown sorghum cv. Serena decreased plant height and dry weights of leaf sheaths, stems, ears and grains, the effects being more pronounced when leaf removal was performed at the flag leaf stage than at anthesis. The proportion of DM in the ear at harvest was decreased when all leaves or all except the flag leaf were removed. Leaf efficiency of intact leaves, as measured by weight of grain produced/unit area of leaf, increased when leaves were removed, the efficiency being higher with defoliation at anthesis than at the flag leaf stage.