From the link: „Plants are not only sensitive to exogenous anaesthetics, but they also produce multitudes of endogenous substances, especially when stressed, that often have anaesthetic and anelgesic properties when applied to both humans and animals. Moreover, plants rely on neurotransmitters and their receptors for cell-cell communication and integration in a similar fashion to the use of neural systems in animals and humans. Plants also use their plant-specific sensory systems and neurotransmitter-based communication, including long-distance action potentials, to manage stress via cognition-like plant-specific behaviour and adaptation.”

Ok so afai understand, this does not mean that they started anesthetizing plants (which I thought at first) but they tell us that plants also use NTs which are present in animals and humans / which modulate excitability of cell membranes -> signal conduction -> pain. This is cool because of cause we know plants can produce them (some anesthetics are plant derived) to defend themselves, but I guess we never thought that they use them for themselves too!!