Differential accumulation pattern of cadmium in plant parts of pea varieties in response to varying cadmium levels

Cadmium (Cd) contamination of soil poses a major hazard to plants by affecting their morphology, physiology, and molecular structure, resulting inroot and leaf necrosis, leaf chlorosis, and reduction in tissue and organ growth. Due to pea's ability to fix their own nitrogen from the atmosphere through a symbiotic relationship with Rhizobium, pea production may be possible in Cd contaminated soils, but varietal response may vary. That's why an experiment was carried out to check the effect of Cd stress on growth, yield and biochemical characteristics of eight pea varieties (Meteor, Green cross, Sultan, Green gold, Sarsabz, Lina, Climax and Supreme). Three cadmium levels (0, 50 and 100 ppm) were applied to the soil in planters, before sowing of eight pea varieties. The results showed that both Cd treatments had significant negative impact on different vegetative and reproductive traits of pea varieties, particularly Cd @ 100ppm that significantly decreased plant height, number of leaves, leaf area, plant biomass, pod fresh weight, pod length and pod yield per plant.The accumulation of Cd in stem + leaves, pod and seed was significantly different for varieties and Cd treatments with highest Cd concentration was observed in plants grown in 100 ppm Cd level. As Cd level increased, all varieties showed significant decrease in chlorophyll contents and peroxidase activity; whilst superoxide dismutase activity was increased significantly under similar conditions. Overall results indicated that three varieties viz. Green Cross, Green Gold and Lina performed significantly better for yield and yield related traits when they were grown in control and 50 ppm Cd compared to100 ppm Cd level. Moreover, among all pea varieties, Supreme variety showed minimum accumulation of Cd (0.8 mg kg-1) in pea seeds as per WHO permissible limits. It can be concluded from results that four pea varieties (Supreme, Green Cross, Green Gold and Lina) can be grown in soils with mild (50 ppm) Cd contamination, particularly Supreme that accumulates less Cd in consumable part, i.e. seeds. (c) 2023 SAAB. Published by Elsevier B.V. All rights reserved.