Effects of mutual grafting on cadmium accumulation in post-grafting generations of two Bidens pilosa ecotypes

Abstract

ABSTRACTThe effects of mutual grafting on cadmium (Cd) accumulation in post-grafting generations of two Bidens pilosa ecotypes (farmland and mining) were studied in a pot experiment involving the following: ungrafted farmland ecotype (F-CK), the farmland ecotype as the rootstock (F-Rootstock), the farmland ecotype as the scion (F-Scion), ungrafted mining ecotype (M-CK), the mining ecotype as the rootstock (M-Rootstock), and the mining ecotype as the scion (M-Scion). The mutual grafting increased the shoot biomass and photosynthetic pigment contents (chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid) of the post-grafting generations of both ecotypes, with F-Scion and M-Rootstock producing the highest values in their respective ecotypes. However, mutual grafting had no significant effect on the root and shoot Cd contents of the post-grafting generations. Additionally, mutual grafting increased the Cd extraction by the shoots of the post-grafting generations of farmland and mining ecotypes, with the F-Scion and M-Rootstock values 33.94% and 24.07% higher than those of F-CK and M-CK, respectively. Therefore, the mutual grafting of the two ecotypes promoted the growth and ability to extract Cd (phytoremediation ability) of post-grafting B. pilosa generations. Moreover, the farmland ecotype as scion and mining ecotype as rootstock was the best combination.