Differences of Zn uptake in various pakchoi cultivars and relationship between Zn uptake and root exudates

Zinc(Zn) accumulation has been found to vary among pakchoi(Brassica compestris var chinensis (L.) Makino)cultivars It is hypothesized that root exudates may play an important role in the availability and uptake of Zn by these plants The objective of this study , therefore, was to investigate the composition and quantity of root exudates of two different Zn efficiency pakchoi cultivars: Wuyuman (WYM) and Heiyoubaicai (HYB), and determine the relationship between Zn accumulation in these plants and their root exudates The results indicated the total amount of low molecular weight organic acids (LMWOAs) and amino acids in root exudates of WYM cultivar was significantly higher than that of HYB cultivar (significant at P0 05 under Zn deficiency),and the contents of oxalic and alanine in root exudates of WYM was also higher than that of HYB in Zn deficiency The higher total amount of root exudates and contents of oxalic and alanine might be a grounds for the higher Zn accumulation and Zn efficiency of WYM