Figure 2.

Stomatal conductance (A) and leaf temperature (B) of plants subjected to heat shock, drought stress, and a combination of heat shock and drought stress. Measurements were performed as described in “Materials and Methods.” The temperature of leaves subjected to a combination of drought and heat shock is shown to be higher than that of plants subjected to heat shock in the absence of drought. This difference may result from the inability of plants, subjected to the stress combination, to cool their leaves by transpiration because their stomata are closed.