Phenotypic plasticity to drought in seedlings of Panicum coloratum L. is related to collection site

GIORDANO, MC; TOMAS, MA; GRIMOLDI, AA

ANNALS OF APPLIED BIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2019 vol. 175 p. 164 - 171

0003-4746

Phenotypic plasticity is the ability of organisms to modify their phenotype according to environmental changes and allows plants to cope with environmental variation. As phenotypic plasticity is heritable, it may be able to respond to natural or artificial selection if a population is genetically variable for this character and may potentially be a breeding objective in a context of climate change. We estimated and compared the amount of phenotypic plasticity in response to drought in seedlings of different accessions of two varieties (var. makarikariense and var. coloratum) of Panicum coloratum, an allogamous warm season perennial grass, introduced and collected in sites in Argentina with different precipitation regimes. Amount of phenotypic plasticity was quantified in shoot/root biomass, blade/sheath biomass, specific leaf area and leaf area/total biomass. Genetically distinct varieties differed in the phenotypic plasticity of leaf area/total biomass, being makarikariense the variety that showed higher phenotypic plasticity. Accessions within varieties differed also in phenotypic plasticity of blade/sheath, specific leaf area and meanphenotypic plasticity. Mean phenotypic plasticity of each accession showed strong and positive correlation with the heterogeneity index (HI) of the annual mean precipitation calculated at each collection site. Relationships of phenotypic plasticity and other environmental factors are considered. Evidence of a decoupling between phenotypic plasticity of above vs. belowgroundcharacters was apparent; outcomes on the genetic control of phenotypic plasticity and the coordinated response between different organs in the plant are presented.