Alleviation of Cadmium Stress in Saffron (Crocus sativus L.) with Nanoscale and Bulk Sulfur Amendment

The use of inorganic amendments to immobilize cadmium is an eco-friendly approach. The present study aimed to evaluate sulfur nanoparticles (SNPs) for the mitigation of Cd stress in saffron (Crocus sativus L.). A factorial layout based on a completely randomized design with four replications was conducted in greenhouse conditions. Treatments consisted of Cd concentration (0, 15, 30, and 45 mg kg⁻¹) and sulfur amendments (control, SNPs, and bulk sulfur particles (BSPs) at 100 and 200 mg kg⁻¹). In non-contaminated plants, application of BSPs 200 increased stigma and flower dry weight by 127 and 108%, respectively. At Cd 30 mg kg⁻¹, using BSPs 100 yielded the highest stigma and flower dry weight. More daughter corms were produced by using BSPs 100 in control plants and BSPs 200 or SNPs 100 in 45 mg kg⁻¹ Cd. The highest root dry weight measured in Cd 15 mg kg⁻¹ + SNPs 100 and Cd 45 mg kg⁻¹ + SNPs 200. The fertilization effect of BSPs 200 was reflected in the dry weight of the leaf, daughter corms, root, and daughter corm diameter. Roots accumulated the highest Cd concentration, followed by leaves, corms, and stigma. The bioconcentration factor (BCF) in plant tissues was in descending order (BCFroot > BCFleaves > BCFcorm > BCFstigma). The highest total Cd accumulation was detected in 45 mg kg⁻¹ Cd along with SNPs 200. Overall, saffron seemed to be capable of phytostabilizing in managing Cd toxicity by lowering its translocation to aboveground tissues, especially to the stigma.