The interactive effects of light and temperature on heat‐shock protein accumulation in Solidago altissima (Asteraceae) in the field and laboratory

Heat‐shock proteins (HSPs) protect cells from abiotic stresses. However, most work on HSPs in plants has been carried out in laboratory‐grown crop or model species. Few studies have examined field expression of HSPs or HSP expression in response to multiple stresses that often occur simultaneously in nature. Heat stress in nature is frequently accompanied by high light, and photoinhibition is a major limitation for photosynthesis. Light induction of HSPs may help ameliorate damage from excess light. In this study, we asked if accumulation of representative HSPs differed in naturally occurring Solidago altissima (goldenrod) in contrasting light microclimates (open sun vs. shade) and on cool vs. warm days. Our results show that HSP content in field‐grown plants, undergoing natural temperature stress, was greater in open sun than shaded environments. Supporting these results, both light and temperature significantly affected accumulation of HSPs in the laboratory. This is the first study to show that the interaction of light microclimate and temperature can significantly influence HSP accumulation in field‐grown plants.