Abstract:

The purpose of this study is to clarify the effects of exogenous Pb and As pollution on the growth quality and Pb and As accumulation of highland barley, and to provide data support for the prevention and control of heavy metal compound pollution in farmland soil and the improvement of human dietary health. Taking highland barley as the test crop, different concentrations of Pb (480, 720, 960, 1200 and 1440 mg/kg), As (30, 60, 90, 120 and 140 mg/kg) and blank control group (11 treatments in total) were set, and through outdoor pot experiment, the growth, quality and heavy metal accumulation of highland barley under exogenous Pb and As stress were detected. The root length, stem diameter, plant height, ear length, grain number per ear, 1000-grain weight, aboveground and underground dry matter weight of highland barley were significantly reduced by 9.28%-66.58% compared with those of the blank control under exogenous Pb and As stress. Highland barley β-glucan was decreased by 33.58% compared with the blank at Pb concentration of 960 mg/kg, the moisture content was lower than that of the blank, and the contents of ash and protein were higher than those of the blank. Fat was decreased by 54.16% compared with that of the blank at Pb concentration of 1440 mg/kg, and increased by 13.75% compared with that of the blank at Pb concentration of 480 mg/kg. Under different concentrations of exogenous Pb, the content of Pb in highland barley root, stem, leaf and grain were higher than those in the blank. Under different concentrations of exogenous As, the Pb content in highland barley root, stem, leaf and grain were higher than those in the blank. Exogenous Pb and As inhibited the growth and quality of highland barley. The accumulation ability of highland barley to Pb was stronger than that to As, and the accumulation law of Pb and As in various organs was in an order of root > stem and leaf > grain.

Key words: highland barley, exogenous Pb and As, growth, quality, Pb and As accumulation, influence