Your browser doesn't support javascript.
loading
Harnessing the Role of Foliar Applied Salicylic Acid in Decreasing Chlorophyll Content to Reassess Photosystem II Photoprotection in Crop Plants.
Moustakas, Michael; Sperdouli, Ilektra; Adamakis, Ioannis-Dimosthenis S; Moustaka, Julietta; Isgören, Sumrunaz; Sas, Begüm.
Afiliação
  • Moustakas M; Department of Botany, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
  • Sperdouli I; Institute of Plant Breeding and Genetic Resources, Hellenic Agricultural Organisation-Demeter (ELGO-Demeter), 57001 Thessaloniki, Greece.
  • Adamakis IS; Section of Botany, Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece.
  • Moustaka J; Department of Botany, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
  • Isgören S; Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark.
  • Sas B; Department of Botany, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Int J Mol Sci ; 23(13)2022 Jun 24.
Article em En | MEDLINE | ID: mdl-35806045
ABSTRACT
Salicylic acid (SA), an essential plant hormone, has received much attention due to its role in modulating the adverse effects of biotic and abiotic stresses, acting as an antioxidant and plant growth regulator. However, its role in photosynthesis under non stress conditions is controversial. By chlorophyll fluorescence imaging analysis, we evaluated the consequences of foliar applied 1 mM SA on photosystem II (PSII) efficiency of tomato (Solanum lycopersicum L.) plants and estimated the reactive oxygen species (ROS) generation. Tomato leaves sprayed with 1 mM SA displayed lower chlorophyll content, but the absorbed light energy was preferentially converted into photochemical energy rather than dissipated as thermal energy by non-photochemical quenching (NPQ), indicating photoprotective effects provided by the foliar applied SA. This decreased NPQ, after 72 h treatment by 1 mM SA, resulted in an increased electron transport rate (ETR). The molecular mechanism by which the absorbed light energy was more efficiently directed to photochemistry in the SA treated leaves was the increased fraction of the open PSII reaction centers (qp), and the increased efficiency of open reaction centers (Fv'/Fm'). SA induced a decrease in chlorophyll content, resulting in a decrease in non-regulated energy dissipated in PSII (ΦNO) under high light (HL) treatment, suggesting a lower amount of triplet excited state chlorophyll (3Chl*) molecules available to produce singlet oxygen (1O2). Yet, the increased efficiency, compared to the control, of the oxygen evolving complex (OEC) on the donor side of PSII, associated with lower formation of hydrogen peroxide (H2O2), also contributed to less creation of ROS. We conclude that under non stress conditions, foliar applied SA decreased chlorophyll content and suppressed phototoxicity, offering PSII photoprotection; thus, it can be regarded as a mechanism that reduces photoinhibition and photodamage, improving PSII efficiency in crop plants.
Assuntos
Palavras-chave

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Solanum lycopersicum / Complexo de Proteína do Fotossistema II Idioma: En Ano de publicação: 2022 Tipo de documento: Article

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Solanum lycopersicum / Complexo de Proteína do Fotossistema II Idioma: En Ano de publicação: 2022 Tipo de documento: Article