A Micro‐penetration Technique for Mechanical Testing of Plant Cell Walls

A close examination of mechanical “noise” produced during the cutting of potato tuber parenchyma tissue suggested that the signals reflected the summation of the stretching and breaking of individual cell walls. Replacement of the cutting blade by a thin parallel‐sided glass probe, together with the use of very sensitive load‐ and deflection‐transducers, produced a micro‐penetration test capable of resolving individual cell‐wall stretching and breaking events. The use of such data to provide information about mean cell diameters, cell wall fracture energies and cell wall stiffness, together with associated limitations, is discussed.