Abstract

Winter cultivars of rye (Secale cereale L., cv Musketeer) and wheat (Triticum aestivum L. cvs Kharkov and Monopol), but not a spring cultivar of wheat (Glenlea), grown at cold-hardening temperatures showed, at high irradiances, a higher proportion of oxidized to reduced primary, stable quinone receptor (Q(A)) than did the same cultivars grown under nonhardening conditions. In addition, there was a positive correlation between the effects of low-growth temperature on this increased proportion of oxidized Q(A), and a concomitant increase in the capacity for photosynthesis, and LT50, the temperature at which 50% of the seedlings are killed, in cultivars showing different freezing tolerances. This suggests that low-temperature modulation of the photosynthetic apparatus may be an important factor during the induction of freezing resistance in cereals. Finally, the control of photosystem II photochemistry by nonphotochemical quenching of excitation energy was identical for nonhardened and cold-hardened winter rye. However, examination of measuring temperature effects per se revealed that, irrespective of growth temperature, nonphotochemical quenching exerted a stronger control on photosystem II photochemistry at 10-degrees-C rather than at 20-degrees-C.

Published in

Plant Physiology
1993, Volume: 101, number: 1, pages: 245-250
Publisher: AMER SOC PLANT PHYSIOLOGISTS

UKÄ Subject classification

Botany


Publication identifier

DOI: https://doi.org/10.​1104/​pp.​101.​1.​245

Permanent link to this page (URI)

https://res.slu.se/id/publ/76393