From the absorption spectra and the excitation spectra of chlorophyll a fluorescence measured (4-77 °K) at different wavelengths (685-760 nm) and their comparison with the emission spectra published elsewhere 23, we confirm that both the Pigment Systems (I and II) contain chlorophyll b, chlorophyll a 670 and chlorophyll a 678. But System II is relatively enriched in chlorophyll b and System I i...

in this study, the winter cold tolerance of seven strawberry cultivars was evaluated using a rcbd design with a split plot arrangement at bu-ali sina university in 2014. after exposure of plants to low temperatures (+4, -5, -10, -15, -20 and -25oc), the values of electrolyte leakage, index of freeze injury, rwc, total chlorophyll and chlorophyll fluorescence parameters (f0, fm, fv and fv/fm) we...

When the sub-core complex of photosystem II, D1/D2, is irradiated at 436 or 415 nm (absorption by chlorophyll and pheophytin and ß-carotene) or 540 nm (absorption primarily by pheophytin), the low temperature fluorescence spectrum has two maxima, at 685 and 674 nm. This shows the existence of at least two different fluorescent forms of chlorophyll (chlorophyll a and perhaps pheophytin a). When ...

Passive steady-state chlorophyll fluorescence (Fs) provides a direct diagnosis of the functional status of vegetation photosynthesis. With the prospect of mapping Fs using remote sensing techniques, field measurements are mandatory to understand to which extent Fs allows detecting plant stress in different environments. Trees of four common species in Valencia were classified in either a low or...

Subpicosecond fluorescence upconversion has been used to measure the rate of chlorophyll b to chlorophyll a electronic energy transfer in situ within the LHC pigment proteins of Chlamydomonas reinhardtii mutant C2. The time scale of energy transfer is 0.5 & 0.2 ps as determined from the rise time of chlorophyll a fluorescence following chlorophyll b excitation. Estimates of the energy-transfer ...

This Article contains an error in the left hand panel of Fig. 3: the incorrect data for in situ chlorophyll fluorescence is plotted. The correct Fig. 3 appears below as Fig. 1. Figure 1.

− Besides empirical algorithms with the blue-green ratio, the algorithms based on fluorescence are also important and valid methods for retrieving chlorophyll-a concentration in the ocean waters, especially for Case II waters and the sea with algal blooming. This study reviews the history of initial cognitions, investigations and detailed approaches towards chlorophyll fluorescence, and then in...

changes in chlorophyll florescence is one of the physiological responses of plants to waterlogging stress. due to easily measured in field and its inexpensive and non-destructive characteristics, it is one of the best ways to assess different genotypes tolerance to stresses. in this experiment, trends of chlorophyll fluorescence index (fv/fm) of ‘satsuma’ mandarin (citrus unshiu) on seven roots...