Differential plasticity to water and nutrients between crops and their wild progenitors

• Published in: Environmental and experimental botany 2018-01, Vol.145, p.54-63
• Main Authors: Matesanz, Silvia, Milla, Rubén
• Format: Article
• Language: English
• Subjects: Breeding; Crops; Domestication; Functional traits; Norms of reaction; Phenotypic plasticity
• ISSN: 0098-8472; 1873-7307
• DOI: 10.1016/j.envexpbot.2017.10.014

•We compared norms of reaction of functional traits of crops and their wild progenitors.•Domestication effects on phenotypic plasticity to nutrients and water were found.•Domesticated plants decreased performance more under drought than wild plants.•The greater phenotypic homeostasis of wild plants may be a target for future breeding. Crop domestication has resulted in relevant phenotypic divergences between crop plants and wild progenitors, but domestication effects on phenotypic plasticity are poorly known. We grew plants of domesticated and wild progenitor accessions of seven taxonomically-diverse crops in three experimental glasshouse treatments differing in soil water and nutrient availabilities, and measured growth, morphological and physiological traits that are key in plant responses to water and nutrient limitations. We compared growth performance, trait means, and norms of reaction between domestication statuses and crop species. Phenotypes were significantly affected by the experimental treatments. Under low water and low nutrient availabilities, plants decreased specific leaf area to produce smaller and thicker leaves, and decreased stomatal conductance. Plasticity to changes in water availability was more pronounced than to varying nutrient supply. Domesticated and wild accessions significantly differed in plasticity patterns to limiting water for several key traits (maximum height, total leaf area, plant-level photosynthetic rate and growth performance traits). Our results thus provide initial insight into generalized domestication effects on phenotypic plasticity. Importantly, crop plants outperformed wild plants in favorable conditions, but suffered a higher loss of performance under water stress, which contrasts with studies suggesting that selection for high performance in optimum conditions might also improve it in stressful environments. We propose that the greater phenotypic homeostasis of the wild progenitors may be a target for future breeding focused on selection for adaptive norms of reaction in heterogeneous environments.