Leaf ontogeny of Schinus molle L. plants under cadmium contamination: the meristematic origin of leaf structural changes

• Published in: Protoplasma Vol. 254; no. 6; pp. 2117 - 2126
• Main Authors: Pereira, Marcio Paulo, Corrêa, Felipe Fogaroli, de Castro, Evaristo Mauro, de Oliveira, Jean Paulo Vitor, Pereira, Fabricio José
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.11.2017; Springer Nature B.V
• Subjects: Anacardiaceae - cytology; Anacardiaceae - drug effects; Anacardiaceae - growth & development; Anacardiaceae - metabolism; Biomedical and Life Sciences; Cadmium; Cadmium - metabolism; Cadmium - pharmacology; Cell Biology; Contamination; Epidermis; Leaves; Life Sciences; Meristem - cytology; Meristem - drug effects; Meristem - growth & development; Meristem - metabolism; Meristems; Ontogeny; Original Article; Parenchyma; Plant Leaves - cytology; Plant Leaves - drug effects; Plant Leaves - growth & development; Plant Leaves - metabolism; Plant Sciences; Primordia; Schinus molle; Soil Pollutants - metabolism; Soil Pollutants - pharmacology; Stress, Physiological; Structure-function relationships; Toxicity; Zoology; Pepper tree; Leaf primordia; Leaf meristems; Cell elongation rate; Heavy metal
• ISSN: 0033-183X; 1615-6102
• DOI: 10.1007/s00709-017-1103-2

Previous works show the development of thicker leaves on tolerant plants growing under cadmium (Cd 2+ ) contamination. The aim of this study was to evaluate the Cd 2+ effects on the leaf meristems of the tolerant species Schinus molle . Plants were grown in nutrient solution containing 0, 10, and 50 μM of Cd 2+ . Anatomical analysis was performed on leaf primordia sampled at regular time intervals. Under the lowest Cd 2+ level (10 μM), increased ground meristem thickness, diameter of the cells, cell elongation rate, and leaf dry mass were found. However, 50 μM of Cd 2+ reduced all these variables. In addition, the ground meristem cells became larger when exposed to any Cd 2+ level. The epidermis, palisade parenchyma, and vascular tissues developed earlier in Cd 2+ -exposed leaves. The modifications found on the ground meristem may be related to the development of thicker leaves on S. molle plants exposed to low Cd 2+ levels. Furthermore, older leaves showed higher Cd 2+ content when compared to the younger ones, preventing the Cd 2+ toxicity to these leaves. Thus, low Cd 2+ concentrations change the ground meristem structure and function reflecting on the development of thicker and enhanced leaves.