Leaf Trait Plasticity and Evolution in Different Plant Functional Types

Abstract

Phenotypic plasticity is the potential of a genotype to form different phenotypes in contrasting environments. Phenotypic plasticity is always present among plant leaves due to modularity of design such that individual leaves can acclimate to their own environment. Plasticity differs among genotypes, populations, and species and as the result plants vary in their capacity to reach the optimum phenotype and maximise fitness under different environmental conditions. Owing to high energy and carbon costs of plasticity, being most plastic does not always guarantee the maximum fitness, and the benefit of a given plastic modification depends on the rate of environmental variability, extent of plasticity, potential reversibility, and leaf longevity. There are extensive variations in the degree of plasticity, rate of plastic changes, and reversibility of different leaf chemical, physiological, and structural leaf traits. In particular, leaf chemical and physiological traits change faster and more reversibly than structural traits. Leaf photosynthetic plasticity is often structural, determined during leaf development, and therefore, largely irreversible, especially the light‐dependent plasticity. Plant adaptability to the environment is driven by plasticity and ecotypic adaptation to environmental conditions and species from different plant functional types largely vary in the share of different adaptability components along resource availability gradients. Globally, the plastic component is expected to be greater in species from high resource habitats with higher leaf metabolic activity and leaf turnover and less in species from low resource habitats with opposite suite of leaf traits. Plant functional types with persistent leaves and low leaf metabolic activity rely primarily on high constitutive tolerance to survive adverse environmental conditions, whereas plant functional types with short leaf lifespan and high leaf metabolic activity survive adverse conditions by plastic trait modifications or avoidance (ephemerals). Future work should focus on understanding the global variation in leaf plasticity as driven by plant metabolic activity and rate of regulation of transcriptome and epigenome level changes.

Combined Acute Ozone and Water Stress Alters the Quantitative Relationships between O3 Uptake, Photosynthetic Characteristics and Volatile Emissions in Brassica nigra

“…Nevertheless, O 3 exposure resulted in surprisingly minor modifications in volatile profiles in the annual plant B. nigra compared with observations for perennial species. This might be indicative of high ozone tolerance of B. nigra , but also reflect the general strategy of annual species that have a rapid leaf turnover and, instead of responding stronger after the stress and repairing the damages, might sacrifice the heavily damaged leaves to form new leaves [ 144 ]. In the current study, we looked at O 3 responses right after exposure and through 22 h recovery, but O 3 exposure can have longer-term effects, including initiation of acclimation responses that improve plant tolerance to sustained mild chronic O 3 stress [ 145 , 146 ].…”

Wounding-Induced VOC Emissions in Five Tropical Agricultural Species

“…A quantitative analysis of lightweight oxygenated volatiles, fatty acid derived compounds, volatile isoprenoids, monoterpenes, and sesquiterpenes was performed to confirm the structure of the ions measured by PTR-TOF-MS. GC-MS was calibrated using authentic standards (Sigma-Aldrich, St. Louis, MO, USA) for key LOX, mono- and sesquiterpenes, and benzenoids, as described in detail in Kännaste et al [ 62 ]. The identification of compounds was done on the basis of authentic standards and compound retention times and mass spectra using NIST 14 spectral library using the open-access program OpenChrom ver 1.2.0 (Alder) (Lablicate GmbH, Hamburg, Germany) [ 36 ]. Three replicate measurements per plant species were conducted ( Table S1 ).…”

“…There is particularly limited information of VOC emissions in tropical agricultural plants and about their wounding responses, despite their high contribution to worldwide vegetation cover. Given the high physiological activity of agricultural plants, including high photosynthetic and growth rates, the rate and degree of induction of defences under different stresses such as wounding stress are expected to be particularly large in agricultural plants [ 36 ]. In contrast, long-living plants in natural communities invest more in structural and chemical constitutive defences and are expected to have greater stress tolerance [ 36 ].…”

“…Given the high physiological activity of agricultural plants, including high photosynthetic and growth rates, the rate and degree of induction of defences under different stresses such as wounding stress are expected to be particularly large in agricultural plants [ 36 ]. In contrast, long-living plants in natural communities invest more in structural and chemical constitutive defences and are expected to have greater stress tolerance [ 36 ]. Nevertheless, there is a wide range of variation in photosynthetic and structural traits in crops [ 37 , 38 , 39 ].…”

Global patterns of leaf construction traits and their covariation along climate and soil environmental gradients

“…As the severity of environmental stresses increases, the number and type of effective trait combinations becomes increasingly constrained by functional trade‐offs that result from constraints on plant growth and survival due to suboptimal temperature, precipitation, and/or soil Ca supply (Fig. 1b; Westoby & Wright, 2006; Delhaye et al ., 2020; Niinemets, 2020). Therefore, trait covariance associated with leaf structure may further constrain the number of available niches in communities exposed to long‐term environmental stresses.…”