PLANT PHYSIOLOGY , Vol 108, Issue 3 995-999, Copyright © 1995 by American Society of Plant Biologists
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WHOLE PLANT, ENVIRONMENTAL, AND STRESS PHYSIOLOGY |
Chilling-Induced Heat Evolution in Plants
M. R. Moynihan, A. Ordentlich and I. Raskin
AgBiotech Center, Cook College, Rutgers University, P.O. Box 231, New Brunswick, New Jersey 08903-0231
Increases in respiration, particularly via the alternative pathway, are
observed in response to chilling. These increases result in increased heat
evolution. We have measured increases in heat evolution in response to
chilling in a number of plant species using a microcalorimeter. After 8 h
of exposure to 8[deg]C, heat evolution in a variety of chilling-sensitive
species increased 47 to 98%. No increase in heat evolution was seen with
the extremely chilling-sensitive ornamental Episcia cupreata Hook. Heat
evolution increased only 7 to 22% in the chilling-resistant species.
Increases in heat evolution were observed when plants were chilled in
constant light or in the dark, but not when plants were chilled at high
humidity. Increased capacity to produce respiratory heat after exposure to
chilling temperatures may contribute to the cold-acclimation process.
