Heat Stress Responses in Cultured Plant Cells

Open Access
Publisher Website
Google Scholar
Abstract
The response of suspension-cultured pear (Pyrus communis cv Bartlett) cells to heat stress was studied using three viability tests: regrowth (culture growth during 10 days after stress); triphenyltetrazolium chloride reduction; and electrolyte leakage. Critical (50% injury) temperatures for a 20-minute exposure were 42°, 52°, and 56°C, respectively, for these viability tests. Electrolyte leakage had the lowest temperature coefficient. Heat stress inhibition of triphenyltetrazolium chloride reducing capacity was much greater if the viability test was conducted 3 days, rather than immediately, after the stress treatment. Consistent with a major role for indirect metabolic strain in heat injury, treatment with 3.6 micromolar cycloheximide and heat stress (20 minutes at 43°C) affected culture regrowth similarly. We conclude that the measurements of direct response are not adequate substitutes for regrowth tests in assessing heat injury to cultured plant cells.