Yeah Pam a real thing.. It seems that when the temps get up into the 90's plants loose more water than it can absorb. At this point it appears that they stop all other growth activity for survival. A couple factors appear to make a difference, fruit size. IE the larger fruited plants will start to transpire at a lower temperature that small fruited plants. Another factor is soil, plants that are in deep organic material appear to be able withstand higher temps. My SWAG is that OM holds moisture around the roots better than chemical fertlizers. My .02 FWIW L.B.