Photoinhibition, xanthophyll cycle and in vivo chlorophyll fluorescence quenching of chilling‐tolerant Oxyria digyna and chilling‐sensitive Zea mays

• Published in: Physiologia Plantarum
• Main Authors: Koroleva, Olga Y., Brüggemann, Wolfgang, Krause, G. Heinrich
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1994
• Subjects: Arctic; Oxyria digyna
• Online Access: http://dx.doi.org/10.1111/j.1399-3054.1994.tb03026.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1399-3054.1994.tb03026.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1399-3054.1994.tb03026.x

The relationship between susceptibility to photoinhibition, zeaxanthin formation and chlorophyll fluorescence quenching at suboptimal temperatures was studied in chilling‐sensitive maize and in non‐acclimated and cold‐acclimated Oxyria digyna , a chilling‐tolerant plant of arctic and alpine habitats. In maize, zeaxanthin formation was strongly suppressed by chilling. Zeaxanthin formed during preillumination at 20°C did not protect maize leaves from photoinhibition during a subsequent high‐light, low‐temperature treatment, as judged from the ratios of variable to maximal fluorescence, F v /F m . However, such preillumination significantly increased non‐photochemical quenching (q N ) at low temperatures, mainly due to an enhancement of the fast‐relaxing q N component (i.e., of energy‐dependent quenching. q E ). In O. digyna , cold‐acclimation resulted in an increased zeaxanthin formation in the temperature range of 2.5–20°C. Cold‐acclimation substantially decreased the susceptibility towards photoinhibition at 4°C, but q N remained nearly unchanged between 2 and 38°C, as compared to control plants. Effects of cold acclimation on photosynthesis, photochemical quenching and quantum efficiency of photosystem II were small and indicated a slight amelioration only of the function of the photosynthetic apparatus at suboptimal temperatures (2–20°Ct. I) is concluded, that the xanthophyll cycle is strongly influenced by cold acclimation, while effects on the photosynthetic carbon assimilation only play a minor role in O. digyna.