Changes of the chlorophyll fluorescence induction kinetics of C3and CAM plants during day/night cycles
✍ Scribed by Claus Buschmann; Irene C. Buchanan-Bollig
- Publisher
- Springer
- Year
- 1983
- Tongue
- English
- Weight
- 504 KB
- Volume
- 4
- Category
- Article
- ISSN
- 0166-8595
No coin nor oath required. For personal study only.
✦ Synopsis
The induction kinetics of the 680 nm chlorophyll fluorescence were measured on attached leaves of Kalanchoe daigremontiana R. Hamet et Pert. (CAM plant), Sedum telephium L. and Sedum spectabile Bor. (C 3 plant in spring, CAM plant in summer) and Raphanus sativus L. (C 3 plant) at three different times during a 12/12 h day/night cycle. During the fluorescence transient the fluorescence intensity at
the O, P and Tqevel (fo, fmax, fst,) was different for the plant species tested; this may be due to their different leaf ~trticture, pigment composition and organization of their photosystems. The kinetics of the fluorescence induction depended on the time of preillumination or dark adaptation during the light/dark cycle but not on the type of primary CO2 fixation mechanism (C 3 and CAM). For dark adapted leaves measured either at the end of the dark phase or after dark adaptation of plants taken from the light phase a higher P-level fluorescence, a higher variable fluorescence (P-O) and a larger complementary area were found than for leaves of plants taken directly from the light phase. This indicates the presence of largely oxidized photosystem 2 acceptor pools during darkness. During the light phase the fluorescence decline after the Pqevel was faster than during the dark phase; from this we conclude that the light adaptation of the photosynthetic apparatus (state 1 ~ state 2 transition, A pH) during the induction period proceeded faster in plants taken from the light phase than in plants taken from the dark phase.