Effects of accumulator plant species straw on the cadmium and nutrient uptake of potato

Abstract

AbstractThe farmland soil contaminated by the cadmium (Cd) has affected the safe production of potato. In this study, the sprouted potato tubers were planted in the artificially prepared Cd‐contaminated soil, and the straws of Cd‐accumulator species (Malachium aquaticum, Conyza canadensis, Galium aparine, and Nasturtium officinale) were mulched on the soil surface to study the effects of Cd‐accumulator plant straw on the Cd accumulation and nutrient uptake of potato. The straws of M. aquaticum and N. officinale increased the biomass. Specifically, the straw of N. officinale increased the root, tuber, stem, and leaf biomass by 51.2%, 28.5%, 85.4%, and 123%, respectively, compared with the control. The straws of M. aquaticum and N. officinale increased the contents of photosynthetic pigments. The straws of accumulator plant species increased the peroxidase activity, while the straws of M. aquaticum, C. canadensis, and N. officinale decreased the superoxide dismutase activity. Meanwhile, only the straws of G. aparine and N. officinale increased the catalase activity. Regarding the nutrient uptake, only the straw of M. aquaticum increased the phosphorus (P) and potassium (K) contents in both tuber and aboveground parts. In terms of the Cd content, only the straw of N. officinale decreased the Cd contents in various organs, while the straws of other accumulator species increased the Cd content to some extent. These results indicate that the straw of N. officinale can promote the growth and reduce the Cd uptake of potato, and should, therefore, be used in the potato cultivation in the Cd‐contaminated farmland soil areas.