Capacity for Energy Dissipation in the Pigment Bed in Leaves With Different Xanthophyll Cycle Pools

1994 ◽  
Vol 21 (5) ◽  
pp. 575 ◽  
Author(s):  
B Demmig-Adams ◽  
WW Iii Adams
Keyword(s):  
Energy Dissipation ◽  
Xanthophyll Cycle ◽  
High Growth ◽  
Full Sunlight ◽  
Growth Irradiance ◽  
Shade Tolerant Species ◽  
Monstera Deliciosa ◽  
Schefflera Arboricola ◽  
Sun Leaves ◽  
Photosynthetic Capacities

Photosynthetic capacities, xanthophyll cycle components, and the capacity for photoprotective dissipation of excess excitation in the chlorophyll pigment bed were compared in two groups of species acclimated to different growth irradiance. These were sun leaves of three species with moderately high maximal photosynthetic capacities, tulip, rose, and periwinkle (Vinca minor), and leaves which had developed under very low irradiance from three shade-tolerant species, Monstera deliciosa, Philodendron caudatum and Schefflera arboricola. All sun leaves possessed larger xanthophyll cycle pools and greater maximal zeaxanthin (and antheraxanthin) contents and also displayed a greater maximal capacity for photo-protective energy dissipation in the pigment bed than the leaves acclimated to very low irradiance. The sun leaves also maintained a considerably lower reduction state of photosystem II at full sunlight than the leaves acclimated to very low irradiance. Thus, during exposure to full sunlight, these sun leaves were able to dissipate a major portion of the absorbed light through the combination of photosynthesis and energy dissipation in the pigment bed. Under the same conditions, these two processes combined were able to dissipate only a small fraction of the absorbed light in the leaves acclimated to very low irradiance. Most of the above differences between sun-acclimated leaves and leaves acclimated to very low irradiance existed not only between species but also within a species. Acclimation of Monstera deliciosa to a high growth irradiance resulted in leaves with a larger xanthophyll cycle pool, a greater maximal zeaxanthin (and antheraxanthin) content, and a greater capacity for energy dissipation in the pigment bed.

Photoregulation and photodamage in Schefflera arboricola leaves adapted to different light environments

1999 ◽  
Vol 26 (5) ◽  
pp. 485 ◽  
Author(s):  
U. Schiefthaler ◽  
A. W. Russell ◽  
H. R. Bolhàr-Nordenkampf ◽  
C. Critchley
Keyword(s):  
Xanthophyll Cycle ◽  
De Novo ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Synthesis Rate ◽  
Long Term Effects ◽  
Photosynthetic Rates ◽  
Full Sunlight ◽  
Schefflera Arboricola ◽  
Sun Leaves

Leaves of the subtropical understorey shrub Schefflera arboricola Hayata growing in full sunlight had higher specific leaf weight, higher chlorophyll a/b ratios, lower total chlorophyll content and a threefold higher xanthophyll cycle pigment content than leaves growing in a naturally shaded, but sunfleck-punctuated, environment. A number of measurements, all made in situ and during natural day/night cycles, were taken as follows: current photochemical capacity (F√F m after 10 min dark-adaptation), size and epoxidation state of the xanthophyll cycle, CO 2 gas exchange and determination of the D1 synthesis rate. In sun leaves the lowest daily F√F m was found to be approximately 0.6, the change from maximum correlating with an increase in zeaxanthin. Daily changes in zeaxanthin were partly due to de novo synthesis and turnover. We suggest that sun leaves can dissipate most of the excess light energy absorbed safely via the photoprotective xanthophyll cycle. D1 synthesis rates did not correlate with photosynthetic photon flux density or F√F m . The shade leaves had high F√F m values and constant photosynthetic rates throughout the day except during sunflecks, when photosynthetic rates increased and D1 synthesis accelerated, all without a substantial decrease in F√F m . It seems that leaves of S. arboricola adapted to natural shade conditions can use sunflecks to contribute significantly to their pro-ductivity. The third leaf type investigated was from greenhouse-grown plants of S. arboricola after exposure to full sunlight. These leaves showed a rapid and large reduction in F√F m (to 0.3), which neither correlated with zeaxanthin formation nor recovered within the same day. From long-term effects following full sunlight exposure of greenhouse-grown plants we suggest that this F√F m reduction actually reflects photodestruction.

Diurnal and acclimatory responses of violaxanthin and lutein epoxide in the Australian mistletoe Amyema miquelii

2001 ◽  
Vol 28 (8) ◽  
pp. 793 ◽  
Author(s):  
Shizue Matsubara ◽  
Adam M. Gilmore ◽  
C. Barry Osmond
Keyword(s):  
Energy Dissipation ◽  
Chlorophyll A ◽  
Xanthophyll Cycle ◽  
Light Exposure ◽  
Higher Plant ◽  
Shade Acclimation ◽  
Chlorophylls A And B ◽  
Sun And Shade ◽  
Sun Leaves ◽  
Β Carotene

This study investigated the chloroplast pigment content of the Australian mistletoe Amyema miquelii (Lehm. ex Miq.) Tiegh. over diurnal periods in sun- and shade-acclimated leaves. Amyema miquelii exhibited the typical higher plant complement of neoxanthin, the xanthophyll cycle pigments, lutein, chlorophylls a and b and β carotene. Substantial levels of lutein epoxide were also present. Interestingly, diurnal light exposure elicited a decrease in lutein epoxide that paralleled the decrease in violaxanthin. Compared with shade-acclimated leaves, sun leaves exhibited reduced lutein epoxide and violaxanthin levels and higher chlorophyll a/b ratios. It is clear that the pools of violaxanthin and lutein epoxide respond in parallel to both diurnal light changes and sun–shade acclimation, although there seemed to be some differences in the recovery characteristics. These results raise a question as to whether lutein and lutein epoxide cycling may provide an auxiliary means of energy dissipation for some species.

Xanthophyll Cycle-Dependent Energy Dissipation and Flexible Photosystem II Efficiency in Plants Acclimated to Light Stress

1995 ◽  
Vol 22 (2) ◽  
pp. 249 ◽  
Author(s):  
B Demmig-Adams ◽  
WW Iii Adams ◽  
BA Logan ◽  
AS Verhoeven
Keyword(s):  
Energy Dissipation ◽  
Photosystem Ii ◽  
Xanthophyll Cycle ◽  
Light Stress ◽  
Photon Flux ◽  
Growth Environment ◽  
Psii Efficiency ◽  
Cycle Dependent ◽  
Shade Leaves ◽  
Sun Leaves

The effect of an acclimation to light stress during the growth of leaves on their response to high photon flux densities (PFDs) was characterised by quantifying changes in photosystem II (PSII) characteristics and carotenoid composition. During brief experimental exposures to high PFDs sun leaves exhibited: (a) much higher levels of antheraxanthin + zeaxanthin than shade leaves, (b) a greater extent of energy dissipation in the light-harvesting antennae, and (c) a greater decrease of intrinsic PSII efficiency that was rapidly reversible. During longer experimental exposures to high PFD, deep-shade leaves but not the sun leaves showed slowly developing secondary decreases in intrinsic PSII efficiency. Recovery of these secondary responses was also slow and inhibited by lincomycin, an inhibitor of chloroplast-encoded protein synthesis. In contrast, under field conditions all changes in intrinsic PSII efficiency in open sun-exposed habitats as well as understory sites with intense sunflecks appeared to be caused by xanthophyll cycle-dependent energy dissipation. Furthermore, comparison of leaves with different maximal rates of electron transport revealed that all leaves compensated fully for these differences by dissipating very different amounts of absorbed light via xanthophyll cycle-dependent energy dissipation, thereby all maintaining a similarly low PSII reduction state. It is our conclusion that an increased capacity for xanthophyll cycle-dependent energy dissipation is a key component of the acclimation of leaves to a variety of different forms of light stress, and that the response of leaves to excess light experienced in the growth environment is thus likely to be qualitatively different from that to sudden experimental exposures to PFDs exceeding the growth PFD.

The half-life of the cytochrome bf complex in leaves of pea plants after transfer from moderately-high growth light to low light

2017 ◽  
Vol 44 (3) ◽  
pp. 351 ◽  
Author(s):  
Hui Zhu ◽  
Ling-Da Zeng ◽  
Xiao-Ping Yi ◽  
Chang-Lian Peng ◽  
Wang-Feng Zhang ◽  
...  
Keyword(s):  
Half Life ◽  
Time Course ◽  
Photosynthetic Capacity ◽  
High Growth ◽  
Limiting Factor ◽  
Low Light ◽  
High Photosynthetic Capacity ◽  
Growth Irradiance ◽  
The Difference ◽  
Time Courses

The content of cytochrome (cyt) bf complex is the main rate-limiting factor that determines light- and CO2-saturated photosynthetic capacity. A study of the half-life of the cyt f content in leaves was conducted whereby Pisum sativum L. plants, grown in moderately high light (HL), were transferred to low light (LL). The cyt f content in fully-expanded leaves decreased steadily over the 2 weeks after the HL-to-LL transfer, whereas control leaves in HL retained their high contents. The difference between the time courses of HL-to-LL plants and control HL plants represents the time course of loss of cyt f content, with a half-life of 1.7 days, which is >3-fold shorter than that reported for tobacco leaves at constant growth irradiance using an RNA interference approach (Hojka et al. 2014). After transfer to LL (16 h photoperiod), pea plants were re-exposed to HL for 0, 1.5 h or 5 h during the otherwise LL photoperiod, but the cyt f content of fully-expanded leaves declined practically at the same rate regardless of whether HL was re-introduced for 0, 1.5 h or 5 h during each 16 h LL photoperiod. It appears that fully-expanded leaves, having matured under HL, were unable to increase their cyt f content when re-introduced to HL. These findings are relevant to any attempts to maintain a high photosynthetic capacity when the growth irradiance is temporarily decreased by shading or overcast weather.

Xanthophyll cycle, light energy dissipation and photosystem II down-regulation in senescent leaves of wheat plants grown in the field

2001 ◽  
Vol 28 (10) ◽  
pp. 1023 ◽  
Author(s):  
Congming Lu ◽  
Qingtao Lu ◽  
Jianhua Zhang ◽  
Qide Zhang ◽  
Tingyun Kuang
Keyword(s):  
Energy Dissipation ◽  
Photosystem Ii ◽  
Excitation Energy ◽  
Xanthophyll Cycle ◽  
Light Energy ◽  
Photochemical Quenching ◽  
Down Regulation ◽  
Psii Efficiency ◽  
Psii Photochemistry ◽  
Assimilation Capacity

Photosynthesis, the xanthophyll cycle, light energy dissipation and down-regulation of photosystem II (PSII) in senescent leaves of wheat plants grown in the field were investigated. With the progress of senescence, maximal efficiency of PSII photochemistry decreased only slightly early in the morning but substantially at midday. Actual PSII efficiency, photochemical quenching, efficiency of excitation capture by open PSII centres, and the I–P phase of fluorescence induction curves decreased significantly and such decreases were much more evident at midday than in the morning. At the same time, non-photochemical quenching, thermal dissipation and de-epoxidation status of the xanthophyll cycle increased, with much greater increases at midday than in the morning. These results suggest that the xanthophyll cycle played a role in photoprotection of PSII in senescent leaves by dissipating excess excitation energy. Taking into account the substantial decrease in photosynthetic capacity in senescent leaves, our data seem to support the view that the decrease in actual PSII efficiency in senescent leaves may represent a mechanism to down-regulate photosynthetic electron transport to match the decreased CO2 assimilation capacity and avoid photodamage of PSII from excess excitation energy.

Mangrove Photosynthesis: Response to High-Irradiance Stress

1988 ◽  
Vol 15 (2) ◽  
pp. 43 ◽  
Author(s):  
O Bjorkman ◽  
B Demmig ◽  
TJ Andrews
Keyword(s):  
Energy Dissipation ◽  
Photosystem Ii ◽  
Energy Conversion ◽  
O2 Evolution ◽  
Photon Yield ◽  
Mangrove Species ◽  
Reaction Centres ◽  
Fluorescence Characteristics ◽  
Shade Leaves ◽  
Sun Leaves

Efficiencies of photosynthetic energy conversion were determined in sun and shade leaves of several mangrove species, growing in an open intertidal habitat in North Queensland, by measuring the maximum photon yield of O2 evolution and 77K chlorophyll fluorescence characteristics. Preliminary meas- urements confirmed that mangrove leaves have low water potentials, low stomatal conductances and low light-saturated CO2 exchange rates. Mangrove sun leaves therefore received a very large excess of excitation energy. Mangrove shade leaves had as high a photon yield of O2 evolution as non-mangrove leaves and their fluorescence characteristics were normal, showing that the energy conversion efficiency was unaffected by the high salinity. Mangrove sun leaves had markedly depressed photon yields and fluorescence was severely quenched showing that the efficiency of the photochemistry of photosystem II was reduced. The efficiency of energy conversion decreased with an increased radiation receipt. No such depression was detected in sun leaves of non-mangrove species growing in adjacent non-saline sites. Shading of man- grove sun leaves resulted in an increase in the efficiency of energy conversion but, in most species, more than 1 week was required for these leaves to reach the efficiency of shade leaves. Leaves exposed to direct sunlight had somewhat higher efficiencies in mangrove plants cultivated in 10% seawater as compared with full-strength seawater but the salinity of the culture solution had little effect on the increase in the efficiency upon shading. Field and laboratory fluorescence measurements indicated that the reduced efficiency of energy conversion in mangrove sun leaves resulted from a large increase in the rate constant for radiationless energy dissipation in the antenna chlorophyll rather than from damage to the photosystem II reaction centres. We propose that this increase in radiationless energy dissipation serves to protect the reaction centres against damage by excessive excitation.

Sign in / Sign up

Export Citation Format

Share Document