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Changes in chlorophyll a fluorescence, photosynthetic CO 2 assimilation and xanthophyll cycle interconversions during dehydration in desiccation-tolerant and intolerant liverworts

Authors :
Vicente I. Deltoro
Angeles Calatayud
Anunciación Abadía
Cristina Gimeno
Eva Barreno
Source :
Planta. 207:224-228
Publication Year :
1998
Publisher :
Springer Science and Business Media LLC, 1998.

Abstract

The interactions among water content, chlorophyll a fluorescence emission, xanthophyll interconversions and net photosynthesis were analyzed during dehydration in desiccation-tolerant Frullania dilatata (L.) Dum. and desiccation-intolerant Pellia endiviifolia (Dicks) Dum. Water loss led to a progressive suppression of photosynthetic carbon assimilation in both species. Their chlorophyll fluorescence characteristics at low water content were: low photosynthetic quantum conversion efficiency, high excitation pressure on photosystem II and strong non-photochemical quenching. However, dissipation activity was lower in P. endiviifolia and was not accompanied by a rise in the concentration of de-epoxidised xanthophylls as F. dilatata. The photosynthetic apparatus of F. dilatata remained fully and speedily recuperable after desiccation in as indicated by the restoration of chlorophyll fluorescence parameters to pre-desiccation values upon rehydration. A lack of recovery upon remoistening of P. endiviifolia indicated permanent and irreversible damage to photosystem II. The results suggest that F. dilatata possesses a desiccation-induced zeaxanthin-mediated photoprotective mechanism which might aid photosynthesis recovery when favourable conditions are restored by alleviating photoinhibitory damage during desiccation. This avoidance mechanism might have evolved as an adaptative response to repeated cycles of desiccation and rehydration that represent a real threat to photosynthetic viability.

Details

ISSN :
14322048 and 00320935
Volume :
207
Database :
OpenAIRE
Journal :
Planta
Accession number :
edsair.doi...........8383b65a6745ebed19ec37b7a4a29e38
Full Text :
https://doi.org/10.1007/s004250050476