Elemental allelopathy by an arsenic hyperaccumulating fern,Pteris vittata L.  

作　　者：Benjamin D.Jaffe Michael E.Ketterer Stephen M.Shuster 

机构地区：[1]Department of Biological Sciences,Northern Arizona University,617 S.Beaver St.PO Box 5640,Flagstaff,AZ 86011,USA [2]Department of Chemistry,Metropolitan State University of Denver,PO Box 173362,Denver,CO 80217,USA

出　　处：《Journal of Plant Ecology》2018年第4期553-559,共7页植物生态学报（英文版）

摘　　要：Aims the functional advantages of arsenic(As)hyperaccumulation by plants are poorly understood.One proposed benefit,termed ele-mental allelopathy,occurs when hyperaccumulated As is cycled from the plant back into the top layer of soil,allowing As hyperaccu-mulators to gain an advantage over intolerant species by increasing soil As concentrations([As])underneath their canopy.to date,there are no studies that detail the presence of increased soil[As]associ-ated with As hyperaccumulators.In this study,we documented vari-ation in the soil[As]associated with the Chinese brake fern,Pteris vittata L.and also compared the effects of environmentally relevant soil and solution[As]on competitor plant growth.Methods Four populations of P.vittata were identified in central Florida,USA.P.vittata tissue samples and soil samples were collected at the base of and at 3 m away from ferns in each population(n=36).Five sample locations were randomly selected from each site,and soils from the base and 3 m away from each fern were collected to examine the effects of naturally occurring soil[As]on the germination and growth of a potential competitor plant(Oxalis stricta).Solutions with increasing[As]were also used to examine the threshold for negative effects of[As]on O.stricta growth.[As]were measured using inductively coupled plasma mass spectrometry(ICP-MS).Important Findings Overall,soil[As]from the base of ferns was nearly twice that of soil 3 m away indicating that ferns hyperaccumulate As.However,ferns and their associated soil,contained different[As]depending on their col-lection site,indicating that these populations accumulate and use[As]differently.O.stricta growth decreased and germination was delayed as solution and soil[As]increased.However,the relative distance from the fern that the soil was collected from did not affect growth,which would be expected with elemental allelopathy.Our results show that P.vittata is associated with higher soil[As]and these concentrations are sufficient to inhibit growth of competitors.Howeve

关 键 词：Pteris vittata Chinese brake fern soil ARSENIC HYPERACCUMULATION elemental allelopathy plant-plant competition physiological ecology 

分 类 号：S15[农业科学—土壤学]