New insights into cadmium tolerance and accumulation in tomato: Dissecting root and shoot responses using cross-genotype grafting

Deyvid Novaes Marques; Marina Lima Nogueira; Salete Aparecida Gaziola; Katherine Derlene Batagin-Piotto; Natália Chagas Freitas; Berenice Kussumoto Alcantara; Luciano Vilela Paiva; Chase Mason; Fernando Angelo Piotto; Ricardo Antunes Azevedo

doi:10.1016/j.envres.2022.114577

New insights into cadmium tolerance and accumulation in tomato: Dissecting root and shoot responses using cross-genotype grafting

Environ Res. 2023 Jan 1;216(Pt 2):114577. doi: 10.1016/j.envres.2022.114577. Epub 2022 Oct 14.

Affiliations

¹ Department of Genetics, University of São Paulo/Luiz de Queiroz College of Agriculture (USP/ESALQ), Piracicaba, SP, Brazil. Electronic address: deyvidnovaes@gmail.com.
² Department of Genetics, University of São Paulo/Luiz de Queiroz College of Agriculture (USP/ESALQ), Piracicaba, SP, Brazil.
³ Central Laboratory of Molecular Biology, Department of Chemistry, Federal University of Lavras (UFLA), Lavras, MG, Brazil.
⁴ Center of Biological and Natural Sciences, Federal University of Acre, Rio Branco, AC, Brazil.
⁵ Department of Biology, University of Central Florida, Orlando, FL, USA.
⁶ Department of Crop Science, University of São Paulo/Luiz de Queiroz College of Agriculture (USP/ESALQ), Piracicaba, SP, Brazil.

PMID: 36252830
DOI: 10.1016/j.envres.2022.114577

Abstract

Cadmium (Cd) is one of the most threatening soil and water contaminants in agricultural settings. In previous studies, we observed that Cd affects the metabolism and physiology of tomato (Solanum lycopersicum) plants even after short-term exposure. The objective of this research was to use cross-genotype grafting to distinguish between root- and shoot-mediated responses of tomato genotypes with contrasting Cd tolerance at the early stages of Cd exposure. This study provides the first report of organ-specific contributions in two tomato genotypes with contrasting Cd tolerance: Solanum lycopersicum cv. Calabash Rouge and Solanum lycopersicum cv. Pusa Ruby (which have been classified and further characterized as sensitive (S) and tolerant (T) to Cd, respectively). Scion S was grafted onto rootstock S (S/S) and rootstock T (S/T), and scion T was grafted onto rootstock T (T/T) and rootstock S (T/S). A 35 μM cadmium chloride (CdCl₂) treatment was used for stress induction in a hydroponic system. Both shoot and root contributions to Cd responses were observed, and they varied in a genotype- and/or organ-dependent manner for nutrient concentrations, oxidative stress parameters, antioxidant enzymes, and transporters gene expression. The findings overall provide evidence for the dominant role of the tolerant rootstock system in conferring reduced Cd uptake and accumulation. The lowest leaf Cd concentrations were observed in T/T (215.11 μg g^-1 DW) and S/T (235.61 μg g^-1 DW). Cadmium-induced decreases in leaf dry weight were observed only in T/S (-8.20%) and S/S (-13.89%), which also were the only graft combinations that showed decreases in chlorophyll content (-3.93% in T/S and -4.05% in S/S). Furthermore, the results show that reciprocal grafting is a fruitful approach for gaining insights into the organ-specific modulation of Cd tolerance and accumulation during the early stages of Cd exposure.

Keywords: Cadmium mitigation; Environmental research; Enzymatic antioxidant; Heavy metal; Oxidative stress tolerance; Solanum lycopersicum.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cadmium* / metabolism
Cadmium* / toxicity
Genotype
Plant Leaves
Plant Roots / metabolism
Solanum lycopersicum* / genetics
Solanum lycopersicum* / metabolism

Substances

Cadmium