Closely related allopatric Podalyria species from the Core Cape Subregion differ in their mechanisms for acquisition of phosphorus,growth and ecological niche

作     者：Pravin M.Maistry A.Muthama Muasya Alex J.Valentine Louise Zdanow Samson B.M.Chimphango 

作者机构：Department of Biological SciencesUniversity of Cape TownPrivate Bag X3Rondebosch 7701South Africa Department of Botany and ZoologyUniversity of StellenboschPrivate Bag X1Matieland 7602South Africa 

出 版 物：《Journal of Plant Ecology》 (植物生态学报（英文版）)

年 卷 期：2016年第9卷第4期

页      面：451-463页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 07[理学] 0901[农学-作物学] 0902[农学-园艺学] 0713[理学-生态学] 

基　　金：National Research Foundation(NRF) University of Cape Town and the Oppenheimer Memorial Trust 

主　　题：climate distribution nodules organic acids root:shoot ratio specific root length 

摘      要：Aims In the Core Cape Subregion(CCR),a Mediterranean-climate ecosystem with infertile soils,the legume species Podalyria calyptrata and *** are in a separate clade to *** and *** closely related species are allopatric,and with the west-east climate gradient and variation in soil nutrient availability in the CCR,it was hypothesized that the two closely related allopatric species would differ in their ecological niche and root:shoot ratio,specific root length(SRL)and organic acid exudation responses to phosphorus(P)*** With increasing P supply in the glasshouse,we measured plant biomass,leaf nitrogen([N]),[P],root morphology and release of organic *** determined species soil and leaf[N]and[P]and climate in field *** FindingsAt low P supply,*** roots exuded more organic acids than *** which instead produced roots with a greater SRL,and *** allocated more biomass to roots than *** the field,leaf[P]and climate suggested that *** occupied the most oligotrophic niche followed by *** and then *** and *** related allopatric species differed in their mechanisms for P-acquisition and ecological niche,indicating that the environment overrides phylogeny in determining P-acquisition traits for these species,and suggesting that climate regulates nutrient availability,driving distribution and speciation.