Oquist G, Hurry VM, Oquist MG, Huner NPA
Differential Resistance of Frost-Hardened and Nonhardened Winter Rye to Photoinhibition of Photosynthesis Is Due to an Increased Capacity of Frost-Hardened Rye to Keep Q(a) Oxidized under Similar Irradiance and Temperature
Photosynthetica: 1992 27:231-235
Chlorophyll fluorescence analysis was conducted to evaluate why the frost-hardened winter rye is more resistant to photoinhibition of photosynthesis at 5-degrees-C than the non-hardened winter rye. Under a similar irradiance, the leaves of frost-hardened rye were able to keep a larger fraction of photosystem 2 reaction centres open than those of non-hardened rye. This ability of the frost-hardened rye fully accounts for its higher resistance to photoinhibition.
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