Enhanced Cd phytoextraction by rapeseed under future climate as a consequence of higher sensitivity of HMA genes and better photosynthetic performance

Austra Dikšaitytė; Inesa Kniuipytė; Jūratė Žaltauskaitė; Mostafa A Abdel-Maksoud; Han Asard; Hamada AbdElgawad

doi:10.1016/j.scitotenv.2023.168164

Enhanced Cd phytoextraction by rapeseed under future climate as a consequence of higher sensitivity of HMA genes and better photosynthetic performance

Sci Total Environ. 2024 Jan 15:908:168164. doi: 10.1016/j.scitotenv.2023.168164. Epub 2023 Oct 31.

Authors

Austra Dikšaitytė¹, Inesa Kniuipytė², Jūratė Žaltauskaitė³, Mostafa A Abdel-Maksoud⁴, Han Asard⁵, Hamada AbdElgawad⁵

Affiliations

¹ Department of Environmental Sciences, Vytautas Magnus University, Universiteto st. 10, LT-53361 Akademija, Kaunas distr., Lithuania. Electronic address: austra.diksaityte@vdu.lt.
² Lithuanian Energy Institute, Laboratory of Heat-Equipment Research and Testing, Breslaujos st. 3, LT-44403 Kaunas, Lithuania.
³ Department of Environmental Sciences, Vytautas Magnus University, Universiteto st. 10, LT-53361 Akademija, Kaunas distr., Lithuania.
⁴ Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
⁵ Integrated Molecular Plant Physiology Research, Department of Biology, University of Antwerp, Antwerp, Belgium.

PMID: 37914112
DOI: 10.1016/j.scitotenv.2023.168164

Abstract

This study aimed to investigate the underlying physiological, biochemical, and molecular mechanisms responsible for Brassica napu's potential to remediate Cd-contaminated soil under current (CC) vs. future (FC) climate (400 vs. 800 ppm of CO₂, 21/14 °C vs. 25/18 °C). B. napus exhibited good tolerance to low Cd treatments (Cd-1, Cd-10, i.e., 1, 10 mg kg^-1) under both climates without visible phytotoxicity symptoms. TI sharply decreased by 47 % and 68 % (p < 0.05), respectively, in Cd-50 and Cd-100 treated shoots under CC, but to a lesser extent (-26 % and -53 %, p < 0.05) under FC. This agreed with increased photosynthetic apparatus performance under FC, primarily due to a significant decrease in the closure of active PSII RCs ((dV/dt)o, TRo/RC) and less dissipated excitation energy (DIo/RC, φDo). Calvin Benson cycle-related enzyme activity also improved under FC with 2.2-fold and 2.4-fold (p < 0.05) increases in Rubisco and TPI under Cd-50 and Cd-100, respectively. Consequentially, a 2.2-fold and 2.3-fold (p < 0.05) boosted P_r resulted in a 2.3-fold and 2.4-fold (p < 0.05) increase in the DW of Cd-50 and Cd-100 treated shoots, respectively. This also led to a decrease (26 %, p < 0.05) in shoot Cd concentration under both high Cd treatments with a slight reduction in BCF. Translocation factor (TF) decreased (on average 42 %, p < 0.05) by high Cd treatments under both climates. However, under Cd-100, FC increased TF by 1.7-fold (p < 0.05) compared to CC, which could be explained by significant increases in the expression of HMA genes, especially BnaHMA4a and BnaHMA4c. Finally, Cd TU increased under FC by 65 % and 76 % (p < 0.05) under Cd-50 and Cd-100. This led to a shorter hypothetical remediation time for reaching the Cd pollution limit by 35 (p > 0.05) and 61 (p < 0.05) years, respectively, compared to CC.

Keywords: Brassica napus; CBC-related enzymes; Future climate; HMA genes; Photosynthetic apparatus performance; Phytoextraction potential.

MeSH terms

Biodegradation, Environmental
Brassica napus* / metabolism
Brassica rapa* / metabolism
Brassica* / metabolism
Cadmium / analysis
Soil
Soil Pollutants* / analysis

Substances

Cadmium
Soil Pollutants
Soil