Search Results

, 2012b ) demonstrated that at temperatures of 20 °C/16 °C (day/night), lettuce plants under 400 and 600 μmol·m −2 ·s −1 exhibited high photochemical quenching (qP), ETR, and yield, as well as moderate nonphotochemical quenching parameter (NPQ) values

( Dannehl et al., 1996 ). In this study, it can be found that the decreased q P is consistent with the decrease of P n ( Fig. 7 ). The q N is an important nonphotochemical quenching parameter, reflecting the changes in the plant heat dissipation

'). In this article, we used the definitions of fluorescence parameters [maximum quantum yield of the PSII (F v /F m ), effective quantum yield of the PSII ( Φ PSII), electron transport rate (ETR), and nonphotochemical quenching (NPQ)] as described by

transfer rate (ETR). ( H ) Nonphotochemical quenching (NPQ). Traits that reflect the health of the light-harvesting system (PSII efficiency or Ф PSII and ETR) for the different cultivars displayed trends similar to those observed in A. However, these

differences were found in relative quantum efficiency of PSII photochemistry (ΦPSII) among Al concentration of 0.5, 1.25 m m, and the control. The nonphotochemical quenching (NPQ) was greatest in the 2.0 m m , followed by those in the control and 0.5 m m Al

the photosystems under high-light conditions ( Powles, 1984 ). Carotenoids function to dissipate excessive energy or excitation nondestructively as heat, a phenomenon being called nonphotochemical quenching (NPQ) of chlorophyll a fluorescence

-harvesting pigments by channeling photons to the photosynthetic reaction center and functioning as photoprotectants by quenching damaging free radicals or through active nonphotochemical quenching of excess light energy ( Croce et al., 1999b ; Niyogi, 1999

under greater PPFD levels or continuous light ( Bian et al., 2016 , 2018 ). Specifically, under greater PPFD s, nonphotochemical quenching could be engaged in upper leaves, whereas in lower leaves, penetrating green light could drive photosynthesis

0 ), photochemical quenching coefficient (q p ), PSII photochemical maximum quantum efficiency (F v /F m ), chlorophyll fluorescence nonphotochemical quenching (NPQ), and actual quantum yield of PSII photochemistry (Φ PSII ). The specific measurement

the lumen (ΔpH) during PSN also senses changes in light, regulates electron transport, and modulates nonphotochemical quenching (NPQ) in PSII ( Foyer et al., 2012 ; Kono and Terashima, 2014 ). The photoprotective xanthophyll cycle is a significant