OCCURRENCE OF TEMPERATURE-SENSITIVE PHENOTYPIC PLASTICITY IN CHLOROPHYLL-DEFICIENT MUTANTS OF ARABIDOPSIS-THALIANA

A collection of 75 putative mutants with alterations in leaf pigmentation was visually selected from Arabidopsis thaliana plants (M2 generation) grown at 26-degrees-C from seeds treated with the mutagen ethylmethanesulfonate. Fifty-eight of the plants were found to have chlorophyll contents decreased by at least 10% from the parental Columbia ecotype. These plants were screened for chlorophyll content and the ratio of chlorophyll b/a after growth at 20 or 26-degrees-C. Relative to the parental type, a significant number of individuals in which the chlorophyll-deficient phenotype was exacerbated at one of the growth temperatures were identified. We conclude that temperature-sensitive phenotypic plasticity for chlorophyll content is relatively common in mutant populations of higher plants.