Morphological, Anatomical, and Molecular Consequences of Growth and Development at Low Temperature in Secale Cereale

Chloroplast biogenesis during continuous illumination at either low, cold-hardening temperatures (5°C) or non-hardening temperatures (20°C) was examined by monitoring the etioplast-chloroplast transformation with respect to pigment accumulation and the development of PSI- and PSII-associated electron transport activities in winter rye (Secale cereale L. cv Puma). Generally, chlorophyll and carotenoid accumulation during greening at 20°C were characterized by rapid initial rates in contrast to pronounced, initial lag times during biogenesis at 5°C. Although greening temperature had no effect on the sequential appearance of PSI relative to PSII, greening temperature significantly altered the pattern of appearance of PSI relative to chlorophyll accumulation. Thylakoid biogenesis under continuous illumination at 20°C imposed a pattern whereby the development of PSI activity was antiparallel to chlorophyll accumulation. In contrast, the development of PSI activity under continuous illumination at 5°C was paralllel to chlorophylll accumulation. These developmental patterns were independent of the temperature experienced during etiolation. However, rye seedlings etiolated at 20°C and subsequently subjected to continuous illumination at 5°C exhibited a 70% reduction in the maximum PSII activity (100 μmol DCPIP reduced.mg Chl(-1).h(-1)) attained relative to that observed for similar etiolated seedlings greened at 20°C (300 μmol DCPIP reduced.mg Chl(-1).h(-1)). This low temperature-induced inhibition could be alleviated by an initial 2 h exposure to continuous light at 20°C prior to greening to 5°C. Rye seedlings etiolated at 5°C attained similar maximal PSII activities (300 μmol DCPIP reduced.mg Chl(-1).h(-1)) regardless of the greening temperature. We suggest that the altered kinetics for pigment accumulation, the low temperature-induced change in the pattern for the appearance of PSI activity relative to chlorophyll accumulation and the differential sensitivity of 20° and 5° etiolated seedlings to greening temperature reflect an alteration in membrane organization incurred as a consequence of thylakoid assembly at low temperature.

show abstract

Morphological, Anatomical, and Molecular Consequences of Growth and Development at Low Temperature in Secale Cereale

Cited by 28 publications

References 81 publications

Morphological, Anatomical and Physiological Responses Related to Differential Shoot vs. Root Growth Inhibition at Low Temperature in Spring and Winter Wheat

Morphological, Anatomical and Physiological Responses Related to Differential Shoot vs. Root Growth Inhibition at Low Temperature in Spring and Winter Wheat

Metabolic Changes During Cold Acclimation and Subsequent Freezing and Thawing

Chloroplast biogenesis at cold-hardening temperatures. Development of photosystem I and photosystem II activities in relation to pigment accumulation

Contact Info

Product

Resources

About