In the roots of plants, casparian strip made of suberin forms a ring around the cells of the endodermis. It effectively blocks the entry of water and mineral ions into the stele via the apoplast. A defect in the casparian strip leads to

Step-by-step solution

The Casparian strip is a band of cell wall material in the endodermis that contains suberin and lignin. It acts as an apoplastic barrier, preventing the passive diffusion of water and solutes into or out of the vascular cylinder (stele). When the Casparian strip is defective, the barrier to the apoplastic pathway is compromised. This allows solutes (such as mineral ions) that were actively pumped into the stele to leak back into the cortex, leading to increased solute leakage. Additionally, the loss of this barrier