Question

Why ringing experiment cannot be performed in monocot stem

Answer 1

The girding experiment refers to the removal of the outer layer of a stem. By doing so, you are cutting off the phloem of a stem, not allowing it's supply to flow to the roots, resulting in their death. The 'food' supplied by the phloem is blocked above the area of removal. For this experiment to be successful, the arrangement of the vascular bundles (xylem and phloem) must in the firm of a ring. This is present in dicots, while monocot plants have scattered vascular bundles i.e that lack organisation. Monocot have random arrangements of xylem and phloem while dicots have a star shaped arrangement.