H. Hartel et H. Lokstein, RELATIONSHIP BETWEEN QUENCHING OF MAXIMUM AND DARK-LEVEL CHLOROPHYLL FLUORESCENCE IN-VIVO - DEPENDENCE ON PHOTOSYSTEM-II ANTENNA SIZE, Biochimica et biophysica acta. Bioenergetics, 1228(1), 1995, pp. 91-94
The effects of nonphotochemical quenching were quantified separately a
pplying the Stern-Volmer formalism for dark level (SV0) and maximum ch
lorophyll fluorescence yield (SVN) in barley leaves comprising a step-
wise altered Photosystem II (PS II) antenna size. Proportions of overa
ll SVN can be attributed to distinct sites of the photosynthetic appar
atus: (i) the bulk light-harvesting complex of PS II (LHC II), (ii) th
e inner LHC II antenna, and (iii) the reaction center/core complex of
PS II. The fraction of SVN which exerts an effect on SV0 appeared to a
rise almost exclusively from the inner LHC II antenna. A strong linear
correlation between SV0 and violaxanthin de-epoxidation points to an
intrinsic relationship of both. The results are in line with the natio
n of a regulatory function of the inner LHC II antenna, thus controlli
ng excitation energy delivery from the bulk LHCII to the PS II-core co
mplex.