The origin and significance of an indent on wheat leaves

Abstract

The origin and significance of an indent on laminae of wheat is unknown. The constancy, position and emergence of a leaf indent was recorded on a range of winter wheat cultivars sown on two dates in 1998/99 and three dates in 1999/2000. The time when the indent developed was also examined in 1999/2000.The indent appeared to be caused by tissue in the region of the ligule on the previous leaf swelling as the ligule formed. The synchrony between a ligule on one leaf and an indent on the next generally lasted until the ligule appeared from within the previous leaf sheath. The date of plant emergence influenced the pattern of tip to indent length throughout the life of the plant and different varieties also showed different patterns. There was strong correlation between the length of a leaf sheath and the length of the next (younger) lamina from the ligule to the indent.