Effects and Evaluations on Germination Period of Wild Leymus secalinus in Different Regions of Tibet under the MnCl2 Stress

XU Yamei; ZHANG Weihong; LIN Yonghe; LIU Dalin; MIAO Yanjun

doi:10.3969/j.issn.1003-6504.2017.05.013

Abstract：In order to study the impact of different concentrations of Mn2+(0,20,50,100,200,300,400 and 500 mg/L)on germination parameters such as germination rate,germination potential,germination index and vigor index of wild Leymus secalinus seeds in different regions and its seedling growth index such as germ length,radicle length,radicle elongation,plumule fresh weight and root fresh weight and the malondialdehyde (MDA) content,wild Leymus secalinus seeds collected from 4 different regions of Tibet were taken as meterials and the box germination method was applied,for the purpose to provide scientific reference for the utilization of Leymus secalinus in the remediation of heavy metals polluted sites in Tibet as well as the evaluation of seed resource of Leymus secalinus.The results showed that both germination parameters and seeding growth index increased with low concentration of manganese,which made germination time at the same time roughly.When the manganese concentration exceeded a certain value,it can inhibit the germination parameters and seedling growth parameters.The germination parameters and seedling growth parameters of different Leymus secalinus seeds reacted to manganese stress differently.Under manganese stress,MDA content in Leymus secalinus increased with the increasing of manganese concentration as a whole.The study showed that the low concentration of manganese can promote the germination and seedling,while high concentration can inhibit them and manganese chloride will result in pernicious effect on Leymus secalinus in the process.Membership function was applied to evaluate Leymus secalinus' Mn-resistance and the results showed that the Leymus secalinus Dagze had stronger resistance to manganese stress.