The organelle that, if empty, would cause the plant to wilt is the vacuole.

Here's why:

* Water Storage: Vacuoles are large, fluid-filled sacs within plant cells. They act as storage compartments for water.

* Turgor Pressure: The water within the vacuole creates pressure against the cell wall, known as turgor pressure. This pressure helps maintain the plant's rigidity and structure.

* Wilting: When the vacuoles lose water, the turgor pressure decreases. This causes the plant cells to become flaccid, leading to the drooping and wilting of the entire plant.

So, an empty vacuole would essentially mean the plant has lost its internal "skeleton" and support system, causing it to sag and wilt.