不同青菜品种吸锌能力差异及与根系分泌物的关系

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

青菜 [Brassicacampestrisvar chinensis(L )Makino]不同品种对土壤中锌的累积吸收有明显差异[1] ,我们推断根系分泌物在青菜吸收锌的过程中可能起着重要作用。因此在本项研究中 ,对 2个不同锌利用效率的青菜品种的根系分泌物组成、数量及其与锌吸收的关系进行了探讨。结果表明 ,2种锌水平下 ,五月慢根系分泌物中低分子量有机酸及氨基酸的总量均明显高于黑油白菜 ,缺锌时品种间差异达 0 0 5显著水平 ;缺锌条件下 ,五月慢根系分泌物中草酸、丙氨酸的含量同样显著高于黑油白菜。五月慢在缺锌时有较高的根系分泌物总量及其草酸、丙氨酸含量都显著增加 ,这可能是五月慢具有较高累积吸锌量及锌利用效率的重要原因之一。

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 P≤0 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