PJB-2020-415
Cadmium accumulation in duckweed relates with pH level and oxalate synthesis in Cd shock
Na Li
Abstract
Anthropogenic activities increased cadmium (Cd) pollution especially in aquatic environment. Phytoremediation by duckweed is an ideal way to remove Cd. pH and organic matter have import roles in bioavailability of Cd. Here we showed the effect of different pH on Cd accumulation and the effect of Cd addition to pH and organic acid. The highest Cd2+ accumulation was measured under pH 6.3. The Cd2+ influx of rhizoid at pH 5.3 was significantly lower than that at pH 6.3. The H+ influx rate at pH 6.3 gradually decreased, and then became to efflux around 15 min. Cd stress affected pH value in the rhizoid of duckweed, and also enhanced the expression of genes related to Na+/H+ exchange. Oxalate content was increased with Cd shock, and some of the enzymes related to catalyzing oxalate synthesis have been improved under Cd stress. Our results found the roles of NHX1 and NHX2 in regulating intravacuolar Na+ and pH, which were essential to cell expansion and flower development. These results indicated the roles of pH and oxalate during short-term Cd stress and Cd accumulation.
To Cite this article:
Download
