interactive effects of salicylic acid and silicon on growth, development and cadmium accumulation in tuber of potato plants under cadmium stress

Soil accumulation with toxic metals and their transmition into agricultural products as a world problem is ever expanding. Cadmium (Cd) content of soil has increased due to luxury consumption of phosphorous fertilizers application which enters human food chain. In present study which was conducted in college of agriculture, Kerman University in 2010, the effects of chemical treatments namely salicylic (SA) at 0.1mM, silicon (Si) at 5 mM and SA+Si (0.1 mM and 5 mM) was studied on growth and development and cadmium accumulation in potato tubers grown under cadmium stress (0 and 12 mg/kg soil) in a pot experiment, using a factorial experiment with three replications. Compared with control treatment (No Cd), Cd decreased relative water content (RWC), photosynthetic and plant growth parameters. It also increased leaf malondialdehyde (MDA) and Cd accumulation in tubers. All chemical treatments improved plant performance under Cd stress and non-stress conditions and the effect of SA+Si was more pronounced for most recorded parameters. However, under Cd stress, combination of SA+Si increased tuber number (81%) , tuber fresh weight (112%), chlorophylls (50%) and decreased MDA (50%) and Cd accumulation in tubers (85%), relative to corresponding control and therefore, this treatment (SA+Si) can be commercially used to improve plant performance and reduce tuber Cd contents under field conditions.