Chapter 15 The Chemistry and Biology of Light-Harvesting Complex II and Thylakoid Biogenesis: raison d’etre of Chlorophylls b and c

Water relations, biochemical – physiological and yield responses of olive trees (Olea europaea L. cvs. Arbequina and Manzanilla) under drought stress during the pre-flowering and flowering period

“…In general, at the end of the RDI application period, the ratio Chl-a/Chl-b showed lower values in RDI treatments with higher water deprivation. This fact may be explained in terms of differential stability of these pigments -under abiotic stress conditions -which could affect the stability of light-harvesting complexes involved in light absorption (Hoober et al, 2010) and, consequently, the photosynthetic rate. 10.8 a,A ± 1.95 14.1 b,A ± 4.75 14.3 b,A ± 3.70 15.1 b,A ± 2.21 18.5 c,A ± 5.84 Car IV 7.18 a,B ± 0.74 7.23 a,B ± 0.44 7.56 a,B ± 0.47 7.45 a,B ± 0.34 7.44 a,A ± 0.37 EV 5.04 a,A ± 0.47 6.29 b,A ± 1.81 6.17 c,A ± 1.48 6.46 c,A ± 0.73 7.77 c,A ± 2.36 Total Phae IV 13.4 a,B ± 0.58 13.1 a,B ± 0.70 13.7 a,B ± 0.59 13.6 a,B ± 0.84 13.5 a,A ± 0.87 EV 7.61 a,A ± 1.93 10.7 b,A ± 3.56 10.9 b,A ± 2.93 11.9 b,A ± 2.23 14.6 c,A ± 4.21 Phae/Chl IV 0.79 a,B ± 0.03 0.77 a,A ± 0.04 0.78 a,A ± 0.03 0.79 a,A ± 0.05 0.78 a,A ± 0.03 EV 0.73 a,A ± 0.11 0.76 ab,A ± 0.05 0.76 ab,A ± 0.04 0.78 b,A ± 0.06 0.80 b,A ± 0.06…”

Formyl group modification of chlorophyll a: a major evolutionary mechanism in oxygenic photosynthesis

“…1) causes a blue shift of the maximum absorption Q y band to 647 nm (in methanol; Table 1). These shifts can be understood in terms of the position of the electronegative formyl group on the different molecular axes and the effect that this has on the electron density distribution of the tetrapyrrole macrocycle changes (Hoober, Eggink & Chen 2007; Hoober et al . 2010).…”