The influence of barley genotype and growing conditions on zinc and cadmium accumulation

¹ Competence Center «Environmental Technologies and Systems», 610000, 36, Vyatka State University, Moskovskya st., Kirov, Russian Federation
² Laboratory of biotechnology of plants and microorganisms, N.V. Rudnitsky Federal Agricultural Science Center of the North-East, 610007, 166a, Lenina St., Kirov, Russian Federation

^* Corresponding author: usr20174@vyatsu.ru

Abstract

Zinc and cadmium accumulation of in plant tissues of barley of the line 999-93 and of its regenerant forms resulting from cell selection was assessed. The scheme of the experiment: 1) control; 2) acidic; 3) cadmium. We used the method of inversion voltammetry to assess the share of zinc and cadmium in plant samples. To assess the share of active and total forms of zinc and cadmium in soil samples collected from root rhizosphere we used the method of atomic absorption spectroscopy. Barley plants accumulated zinc from 0.2 to 79.7 mg∙kg^-1 of dry phytomass. The genotype of plants has little influence on zinc accumulation, and plant organs participate in equal measure in zinc accumulation. As for the soil background with cadmium excess, there is a tendency to lessening zinc absorption in all the plant organs, and it is not connected with the plant’s genotype. Unlike zinc, cadmium gets accumulated mostly in the root system. In the control background the share of cadmium in roots was 0.2–0.4 mg∙kg^-1; in the acidic one – 0.2–3.6 mg∙kg^-1; in the cadmium one – 5.5–9.5 mg∙kg^-1. In barley grain grown on soil with excess of cadmium we did not find any IPC excess of cadmium. On backgrounds of the same acidity, the more cadmium concentration grew, the less zinc concentration in grain was, mostly it concerns the original genotype, to a smaller degree it concerns the regenerant line on the selective medium with cadmium and aluminum. Coupling accumulation of zinc and cadmium took place mostly on acidic background, it was characteristic of barley with the original genotype and the regenerant selected in vitro as cadmium-resistant; on control background coupling accumulation is characteristic of aluminum-resistant regenerant. These regenerant genotypes had a tendency to eliminating cadmium and absorbing zinc.