DYNAMICS OF GENERATING TRANSIENTS OF DELAYED FLUORESCENCE INDUCTION SIGNAL AND PHOTOSYNTHETIC ANTENNAS: A POSSIBLE RELATIONSHIP. MATHEMATICAL

ABSTRACT. A mathematical model was developed for resolved temporal transients of experimentally recorded delayed fluorescence (DF) induction signal. During an intermit-tent light regime, antennas of the photosynthetic apparatus were treated as targets, repea-tedly hit by potentially absorbable photons within a series of consecutive light flashes. For-mulas were derived for the number of antennas, cumulatively hit by a specific number of photons, as function of the flash serial number (time). Model parameters included: number of absorbable photons in one flash, antenna sizes and numbers. A series of induction curves were analyzed, obtained from a Zea mays L. leaf segment and differing in the previous dark period (td). Each curve, consisting of the two most prominent DF transients (C and D), was fitted with several model types, differing in the number of absorbed photons. For both tran-sients, the best fitting result was achieved when DF induction was linked to the second ab-sorbed photon. As expected, model parameters related to antenna sizes showed weaker de-pendence on td than those referring to antenna numbers. With restrictions applied in this model, the two DF induction transients may be related to two classes of photosynthetic an-tennas. Their different sizes may have a predominant influence on the efficiency of photon absorption, and possibly time-dependent appearance of DF transients. KEY WORDS: delayed fluorescence, photosynthetic antennas, induction transients, mathematical modeling, Zea mays L