锰过量对平邑甜茶生长及^(15)N吸收、利用与分配的影响

Effects of Excess Mn on Growth of Malus hupenhensis and Absorption,Utilization and Allocation of ^(15)N

以平邑甜茶为试材,采用15N示踪技术研究了锰过量对平邑甜茶的生长以及对15N吸收、利用及分配的影响。结果表明:随着锰浓度加大,植株的生物量显著降低,50、150、300、450 mg/kg 4个处理的总生物量分别为对照的84.2%、73.6%、51.7%和39.6%;处理的根、茎、叶中Ndff值均低于对照;茎中15N分配率随处理浓度加大而逐渐升高,根和叶中15N分配率均以150 mg/kg为界,分别呈先升高后降低和先降低后升高的趋势。植株15N利用率随锰浓度加大而显著降低,50、150、300、450 mg/kg 4个处理的15N利用率分别是4.546%、2.170%、1.842%和1.166%,均显著低于对照。

The effects of excess Mn on plant growth of potted Malus hupenhensis and absorption,allocation and utilization of 15N were studied in this paper by 15N trace technique.The results showed that the plant biomass reduced significantly as the Mn amount increased,and the total biomass of the four treatments with 50,150,300 and 450 mg/kg Mn were 84.2%,73.6%,51.7% and 39.6% of that of the control respectively.The Ndff value of roots,stems and leaves in treated plants were all lower than that of control.The 15N allocation ratio to stems increased with the increase of Mn amount,while that to roots increased firstly and then decreased,and that to leaves decreased at first then increased both with 150 mg/kg as the boundary.As the Mn stress increased,the 15N utilization reduced significantly,and were 4.546%,2.170%,1.842% and 1.166% respectively after treated with 50,150,300 and 450 mg/kg of Mn.They were all significantly lower than that of control.