Intercropping with hyperaccumulator plants decreases the cadmium accumulation in grape seedlings

In this experiment, four cadmium (Cd) hyperaccumulator species (Crassocephalum crepidioides, Galinsoga parviflora, Sigesbeckia orientalis, and Solanum nigrum) were intercropped with grape (Vitis vinifera) cuttings together in Cd-containated soil to study the effects of intercropping with the Cd-hyperaccumulator plants on growth and Cd accumulation of grape seedlings. Compared with the monoculture, intercropping with S. nigrum increased the biomass of grape seedlings, but intercropping with the other three hyperaccumulator species decreased the grape seedling biomass. Intercropping with S. nigrum increased chlorophyll a and total chlorophyll contents in leaves of grape seedlings compared with the monoculture, whereas intercropping with the other three hyperaccumulator species showed either a decrease or no effect. Intercropping with hyperaccumulator plants had no significant effects on chlorophyll b and carotenoid contents in leaves of grape seedlings compared with the monoculture. Compared with the monoculture, intercropping with C. crepidioides, G. parviflora, S. nigrum and S. orientalis significantly decreased Cd contents in shoots of grape seedlings by 78.7%, 12.7%, 29.8% and 26.5%, respectively. Therefore, intercropping with hyperaccumulator plants can decrease Cd accumulation in grape, and intercropping with S. nigrum can also promote grape seedling growth.