Differences of Absorption and Accumulation of Cd and As in Soil by Different Cultivars of Perennial Ryegrass

PurposeTo study the Cd and As enrichment ability of different perennial ryegrass (Lolium perenne L.) cultivars in soil. The perennial ryegrass cultivars with high enrichment ability were selected to provide a reference basis for the restoration and treatment of Cd and As contaminated soil.

MethodsThirty-one cultivars of perennial ryegrass in Cd and As contaminated soils were used in pot experiments to investigate growth indicators, cumulative characteristics and inter cultivar differences. The enrichment characteristics of Cd and As were comprehensively evaluated by cluster analysis and membership function method.

ResultsThirty-one cultivars of perennial ryegrass could still grow normally in Cd and As contaminated soil, but there were differences among cultivars. Lida, Yatsyn and Bay grew better, but Flash Green, Turfgold and Turfsun grew worse. The contents of Cd and As in the roots of 31 cultivars were higher than in shoots. Except for a few cultivars, perennial ryegrass showed a higher bioconcentration and translocation factor for Cd than As. The top three in the comprehensive evaluation were Bay, Nicaragua and Holly Green.

ConclusionThe accumulation of Cd and As by perennial ryegrass is mainly concentrated in the roots, which are more capable of Cd enrichment. Bay, Nicaragua and Holly Green have strong enrichment ability of Cd and As, which can be prioritized as plant materials for the remediation of Cd and As composite contaminated soils.