Adaptive evolution of chestnut forests to the impact of ink disease in Spain  

作　　者：Francisco Alcaide Alejandro Solla Marcello Cherubini Claudia Mattioni Beatriz Cuenca Alvaro Camisón M.Angela Martín 

机构地区：[1]Institute for Dehesa Research(INDEHESA),Faculty of Forestry,University of Extremadura,Avenida Virgen del Puerto,2,Plasencia 10600,Spain [2]Research Institute on Terrestrial Ecosystems(IRET),Italian National Research Council(CNR),Viale Marconi,2,Porano 05010,Temi,Italy [3]Maceda Nursery,Tragsa-SEPI group,Carretera de Maceda a Baldrei km 2,Maceda 32700,Ourense,Spain [4]Department of Genetics,ETSIAM,University of Cordoba,Campus de Rabanales,Cordoba 14071,Spain

出　　处：《Journal of Systematics and Evolution》2020年第4期504-516,共13页植物分类学报（英文版）

基　　金：This study was supported by grant AGL2014-53822-C2-1-R from the Spanish Ministry of Economy and Competitiveness;the European Union’s European Regional Development Fund(ERDF).

摘　　要：Phytophthora cinnamomi(Pc)is an extremely destructive soil-borne pathogen of Asiatic origin responsible for“ink disease”in chestnut.This work assesses the adaptive potential to the impact of Pc of four Spanish populations of Castanea sativa undergoing different selection pressures.To explore the evolvability of C.satiVa to Pc in the selected populations,parameters obtained from neutral and functional genetic diversity were compared with estimates of quantitative genetic variability.Nine expressed sequence tags-simple sequence repeat(EST-SSR)markers were selected and their transferability and polymorphism in 137 C.sativa individuals were evaluated.To test the potential of EST-SSR markers for early selection of Pc tolerant plant material,the offspring of selected individuals were challenged with Pc.Expressed sequence tags-simple sequence repeat markers and seedling life expectancy after Pc inoculation revealed significant different responses of C.sativa populations to Pc.The genetic variability observed within populations showed the potential response capacity of Spanish C.sativa populations to undergo fast adaptive evolution.The heritability value obtained for the “life expectancy”variable(h^2=0.21±0.11)indicated that selection for resistance to Pc is possible.Genetic patterns reflected two evolutionarily meaningful groupings of populations,corresponding to the different selective pressure of the oomycete between sites.The differentiation coefficient obtained through markers classified as under neutral selection(FST=0.185)was lower than the quantitative genetic differentiation of“life expectancy”between C.sativa populations(QST=0.682),providing evidence that selection acted spatially in a heterogeneous manner.A first link has been identified in trees between population structure and adaptive responses to pathogen-induced selection.The study identified one marker under positive selection that could be used in marker assisted selection to predict resistance to Pc in non-inoculated C.sativa trees.

关 键 词：biotic stress CHESTNUT climate change genetic differentiation HERITABILITY Phytophthora cinnamomi 

分 类 号：Q94[生物学—植物学]