Phenotypic plasticity of growth ring traits in Pinus hartwegii at the ends of its elevational gradient

Lizbeth Carrillo-Arizmendi; J Jesús Vargas-Hernández; Philippe Rozenberg; Marlin Pérez-Suárez; Angel Roberto Martínez-Campos

doi:10.3389/fpls.2023.1072638

Phenotypic plasticity of growth ring traits in Pinus hartwegii at the ends of its elevational gradient

Front Plant Sci. 2023 Sep 20:14:1072638. doi: 10.3389/fpls.2023.1072638. eCollection 2023.

Authors

Lizbeth Carrillo-Arizmendi¹, J Jesús Vargas-Hernández², Philippe Rozenberg³, Marlin Pérez-Suárez¹, Angel Roberto Martínez-Campos¹

Affiliations

¹ Instituto de Ciencias Agropecuarias y Rurales, Universidad Autónoma del Estado de México, Estado de México, Mexico.
² Department of Forestry Sciences, Colegio de Postgraduados, Montecillo, Texcoco, Estado de México, Mexico.
³ UMR 0588 BIOFORA, INRAE Val de Loire, Cedex, Orleans, France.

Abstract

Introduction: Phenotypic plasticity (PP) could be an important short-term mechanism to modify physiological and morphological traits in response to climate change and global warming, particularly for high-mountain tree species. The objective was to evaluate PP response of growth ring traits to temperature and precipitation in Pinus hartwegii Lindl. populations located at the ends of its elevational gradient on two volcanic mountains in central Mexico (La Malinche and Nevado de Toluca).

Methods: Increment cores collected from 274 P. hartwegii trees were used to estimate their PP through reaction norms (RN), which relate the ring width and density traits with climate variables (temperature and precipitation). We estimated the trees' sensitivity (significant RN) to climatic variables, as well as the relative proportion of RN with positive and negative slope. We also estimated the relationship between the PP of ring width and density traits using correlation and Principal Component (PC) analyses.

Results: Over 70% of all trees showed significant RN to growing season and winter temperatures for at least one growth ring trait, with a similar proportion of significant RN at both ends of the gradient on both mountains. Ring width traits had mostly negative RN, while ring density traits tended to have positive RN. Frequency of negative RN decreased from lower to higher elevation for most traits. Average PP was higher at the lower end of the gradient, especially on LM, both for ring width and ring density traits, although high intrapopulation variation in PP was found on both mountains.

Discussion: Results indicate that P. hartwegii presents spatially differentiated plastic responses in width and density components of radial growth. PP was particularly strong at the lower elevation, which has higher temperature and water stress conditions, putting these populations at risk from the continuing global warming driven by climate change.

Keywords: La Malinche; Nevado de Toluca; climate; radial growth; reaction norms.