J A Milburn

J. A. Milburn and R. P. C. Johnson developed an acoustic method for detecting cavitation formation of air bubbles) in plants. This involves "listening" for characteristic clicks produced during air- bubble formation, using sensitive microphones and amplifiers. In one experiment with the castor bean plant Ricinus communis) , they detached leaves by cutting the petioles and subjected them to various treatments. Which of the following would be least likely to be observed in such an experiment?

A) as the leaf is allowed to wilt, recording many clicks that approximately equal the estimated number of vessels in the cut petiole
B) after adding water to the cut end of the petiole, recording an increased rate of clicking
C) after increasing transpiration by blowing warm air across the leaf, recording an increased rate of clicking