Long-term fertilization determines different metabolomic profiles and responses in saplings of three rainforest tree species with different adult canopy position

Abstract

BackgroundTropical rainforests are frequently limited by soil nutrient availability. However, the response of the metabolic phenotypic plasticity of trees to an increase of soil nutrient availabilities is poorly understood. We expected that increases in the ability of a nutrient that limits some plant processes should be detected by corresponding changes in plant metabolome profile related to such processes.Methodology/Principal findingsWe studied the foliar metabolome of saplings of three abundant tree species in a 15 year field NPK fertilization experiment in a Panamanian rainforest. The largest differences were among species and explained 75% of overall metabolome variation. The saplings of the large canopy species, Tetragastris panamensis, had the lowest concentrations of all identified amino acids and the highest concentrations of most identified secondary compounds. The saplings of the “mid canopy” species, Alseis blackiana, had the highest concentrations of amino acids coming from the biosynthesis pathways of glycerate-3P, oxaloacetate and α-ketoglutarate, and the saplings of the low canopy species, Heisteria concinna, had the highest concentrations of amino acids coming from the pyruvate synthesis pathways.Conclusions/SignificanceThe changes in metabolome provided strong evidence that different nutrients limit different species in different ways. With increasing P availability, the two canopy species shifted their metabolome towards larger investment in protection mechanisms, whereas with increasing N availability, the sub-canopy species increased its primary metabolism. The results highlighted the proportional distinct use of different nutrients by different species and the resulting different metabolome profiles in this high diversity community are consistent with the ecological niche theory.

Different “metabolomic niches” of the highly diverse tree species of the French Guiana rainforests

“…Our results clearly indicate that species specificity could explain most of the variance of a metabolomic profile, despite the environmental differences involved in this study (season, site micro-conditions, and topography). A previous study in a Panamanian rainforest also reported differences in metabolomic profiles of sympatric dominant tree species 20 . However, to the best of our knowledge, our study analyses for the first time a broad set of tropical-forest tree species growing in different sites, topographic conditions, and across seasons.…”

“…The classical way to estimate this functional niche is to focus on morphological and functional traits linked to the species strategy that are easier to measure in the field conditions (such as specific leaf area, foliar toughness, …). Numerous studies have combined this conceptual framework with functional foliar traits measurements to explain species coexistence, niche overlap level and thus the competition intensity [17][18][19][20][21][22][23][24] .…”

“…Environmental metabolomics is one of the most recent "omic" technologies and is one of the most important recent developments in the study of plant ecophysiology 31,32 . It allows understanding how much variation in the metabolome is influenced by inherent genetic (constitutive) information and/or by external environmental factors 20,21,[33][34][35] . Environmental metabolomics thus facilitates the understanding of plant processes, from phenotypic plasticity of each species population and thus adaptation capacity to shifts in community composition 36 .…”

Roles of metabolic regulation in developing Quercus variabilis acorns at contrasting geologically-derived phosphorus sites in subtropical China

“…Christian and Oliver [61] showed that Chlamydomonas reinhardtii developed highly distinctive metabolite pro les under N, P, S, or Fe de ciency conditions. Gargallogarriga et al [62] revealed that increased P availability could lead to shifts in the metabolome through higher investments in the protection mechanisms of plants.…”

Microcosm Experiment to Assess the Capacity of a Poplar Clone to Grow in a PCB-Contaminated Soil

“…The selection of plant species for remediation purposes has to take into consideration not only the success of previous studies about the same clone, but also the site-specific conditions, which can influence the effectiveness of the strategy. Plant species can adapt to a specific environment and/or respond to some soil threats by using different strategies, including ecophysiological, structural and biochemical responses Moreover, some soil threats such as contamination, nutrient deficiencies, flooding and warming may alter plant morphology, physiology and biochemistry [24][25][26]. For instance, it is known that hypoxic conditions may lead to a decrease in photosynthetic performance [27][28][29][30] and that the extent of this decrease depends on a species' tolerance to soil hypoxia.…”