The source of ABA for inducing stomatal closure in the detached leaves?

Question

As you may know, when leaves detached from the whole plant close their stomata to maintain water and prevent wilting. Could you please let me know what is the mechanism of stomatal closure in the detached leaves? if it is induced by ABA, what is the source of ABA under these conditions? Please provide me the corresponding links for your answers as I couldn't find an appropriate answer for the question. Thanks

Answer 1

Stomatal opening and closing is largely the result of the turgidity of the surrounding cells. As those cells enjoy abundant water, they change shape, torquing the stomata open to increase the suction that draws the moisture up from the roots. When the moisture decreases, they change back allowing the pores to close, so I would think that, for a period of time at least, this would be the cause of such a reaction in a leaf that is detatched from the mother plant.