Vol.:(0123456789) 1 3 Plant Physiol. Rep. https://doi.org/10.1007/s40502-022-00688-3 ORIGINAL ARTICLE Rhodamine B induced alteration in antioxidant enzymes and photosynthetic performance of Eichhornia crassipes Jyotshana Sharma 1  · Hanwant Singh 1  · Shubhangani Sharma 1  · Deepak Kumar 1  · Upma Bhatt 1  · Vineet Soni 1   Received: 14 July 2022 / Accepted: 22 September 2022 © Indian Society for Plant Physiology 2022 section when the concentration of RhB (50,100,150,200 and 500 mg/l) and exposure period (24, 48, 72, 96 and 120 h) were increased. With diferent concentrations and treatment periods of Rhodamine B, minimal fuorescence (Fo), elec- tron transport efciency per reaction center (ET/RC), and dissipation fux per cross section (DI/CSm) was increased continuously at lower concentration and higher concentra- tion initially increased for a shorter duration after that it decreased when exposure of Rhodamine B was increased. It also decreased the maximal quantum yield of primary pho- tochemistry (ɸPo), the quantum yield of electron transport (ɸEo), and the rate of the trapped exciton (Ψo) while the quantum yield of energy dissipation in PSII antenna (ɸDo) was decreased after increasing exposure time and concen- tration of Rhodamine B. Overall it decreased performance index on absorption (PI ABS ) and cross section (PI CSm ) basis with increased concentration and time of Rhodamine B. The acceptor and donor sides of the PS II RC were destroyed, and energy passage from the antenna to the reaction center was also obstructed, at high concentrations of Rhodamine B according to studies of chlorophyll a fuorescence emis- sion. Overall, Rhodamine B markedly altered photosynthetic performance and antioxidant system in E. crassipes. Keywords Eichhornia crassipes · Rhodamine B · Antioxidant activity · Chl fuorescence · Photosynthesis Introduction The dyestuf manufacturing industrial unit is India’s core chemical sector, and the second-largest export category in the nation (Naik et al., 2013). In the current situation, dye- ing efuents emitted from a variety of dye manufacturing units into receiving water sources have become an alarming Abstract Synthetic dyes are extensively consumed in numerous industrial applications, resulting in the produc- tion of a signifcant amount of toxic efuents. The purpose of this study was to examine how diferent Rhodamine B (RhB) concentrations afected the biochemical and physi- ological functions of Eichhornia crassipes. Therefore, we looked into the ROS-scavenging enzyme activities (Such as SOD, CAT, and GPOD), chlorophyll pigment, and Chl a fu- orescence transient (OJIP test) during 24 to 120 h of Rhoda- mine B exposure at diferent concentrations of dye (50, 100, 150, 200 and 500 mg/L). The antioxidant enzyme showed increased activity with 50 mg/L Rhodamine B application up to 120 h, but at higher dye concentrations (100, 150, 200, and 500 mg/L), it was enhanced initially up to 48 h, then dropped continuously up to 120 h while chlorophyll con- tent decreased as RhB concentration increased in the culture medium. Chlorophyll a fuorescence OJIP kinetics was infu- enced by the treatment of Rhodamine B. The peak of fuo- rescence (Fm) gradually dropped and fattened with increas- ing dye concentration and exposure time length. Treatment of Rhodamine B, increased absorption efciency (ABS/RC), trapped energy (TR/RC), and dissipation energy fuxes per PSII RC (DI/RC) in all experimental plants while it drasti- cally declined the maximal fuorescence (Fm), a ratio of rate constants for photochemical and non-photochemical use of RC (Fv/Fo), reaction center efciency, (RC/CSm) absorp- tion efciency (ABS/CSm), electron transport potential (ET/ CSm), and trapped energy potential (TR/CSm) per cross * Vineet Soni -vineetpbbl154@gmail.com 1 Plant Bioenergetics and Biotechnology Laboratory, Department of Botany, Mohanlal Sukhadia University, Udaipur, Rajasthan 313001, India