TY - JOUR

T1 - Leaf nutrient homeostasis and maintenance of photosynthesis integrity contribute to adaptation of the pea mutant sgecdt to cadmium

AU - Belimov, A.A.

AU - Dodd, I.C.

AU - Safronova, V.I.

AU - Dietz, K.-J.

PY - 2020/6/8

Y1 - 2020/6/8

N2 - Cadmium (Cd) is a highly toxic and widespread soil pollutant, which negatively affects various aspects of plant growth and physiology. Here, the role of photosynthesis in response to Cd was investigated in the Cd-tolerant pea (Pisum sativum L.) mutant SGECdt. The wild type SGE and the mutant SGECdt were grown in a hydroponic solution supplemented with 1, 3, or 4 µM CdCl2 for 12 d. Root and shoot biomasses of the Cd-treated SGECdt were significantly higher than of SGE. Cadmium had little effect on the quantum yield of photosystem II (φPSII) and chlorophyll content of intact leaves of both pea genotypes. However, when leaf slices were taken from Cd-exposed plants and incubated with high Cd concentrations, the SGECdt mutant showed 1.5-2 times higher φPSII values than SGE, with genotypic differences maximal at 0.1 and 1 mM CdCl2. In contrast, when leaf slices were taken from plants previously unexposed to Cd, both pea genotypes exhibited similar φPSII values. Cadmium content in leaves and mesophyll protoplasts of Cd-treated SGECdt were about 2-3 times higher than in SGE ones. The mutant leaves and mesophyll protoplasts had also higher Ca, Mg, Mn, and Zn content. Thus, SGECdt acclimated to Cd during growth in the Cd-supplemented nutrient solution by developing a molecular mechanism related to photosynthetic integrity. A higher foliar nutrient content likely allows enhanced photosynthesis by counteracting the damage of leaves caused by Cd.

AB - Cadmium (Cd) is a highly toxic and widespread soil pollutant, which negatively affects various aspects of plant growth and physiology. Here, the role of photosynthesis in response to Cd was investigated in the Cd-tolerant pea (Pisum sativum L.) mutant SGECdt. The wild type SGE and the mutant SGECdt were grown in a hydroponic solution supplemented with 1, 3, or 4 µM CdCl2 for 12 d. Root and shoot biomasses of the Cd-treated SGECdt were significantly higher than of SGE. Cadmium had little effect on the quantum yield of photosystem II (φPSII) and chlorophyll content of intact leaves of both pea genotypes. However, when leaf slices were taken from Cd-exposed plants and incubated with high Cd concentrations, the SGECdt mutant showed 1.5-2 times higher φPSII values than SGE, with genotypic differences maximal at 0.1 and 1 mM CdCl2. In contrast, when leaf slices were taken from plants previously unexposed to Cd, both pea genotypes exhibited similar φPSII values. Cadmium content in leaves and mesophyll protoplasts of Cd-treated SGECdt were about 2-3 times higher than in SGE ones. The mutant leaves and mesophyll protoplasts had also higher Ca, Mg, Mn, and Zn content. Thus, SGECdt acclimated to Cd during growth in the Cd-supplemented nutrient solution by developing a molecular mechanism related to photosynthetic integrity. A higher foliar nutrient content likely allows enhanced photosynthesis by counteracting the damage of leaves caused by Cd.

KW - Additional calcium

KW - Chlorophyll

KW - Magnesium

KW - Manganese

KW - Protoplast

KW - Quantum yield of photosystem II

KW - Zinc

U2 - 10.32615/bp.2020.061

DO - 10.32615/bp.2020.061

M3 - Journal article

VL - 64

SP - 447

EP - 453

JO - Biologia Plantarum

JF - Biologia Plantarum

SN - 0006-3134

ER -