Determining the scale at which variation in a single gene changes population yields
Abstract
Plant trait diversity is known to influence population yield, but the scale at which this happens remains unknown: divergent individuals might change yields of immediate neighbors (neighbor scale) or of plants across a population (population scale). We use Nicotiana attenuata plants silenced in mitogen-activated protein kinase 4 (irMPK4) – with low water-use efficiency (WUE) – to study the scale at which water-use traits alter intraspecific population yields. In the field and glasshouse, we observed overyielding in populations with low percentages of irMPK4 plants, unrelated to water-use phenotypes. Paired-plant experiments excluded the occurrence of overyielding effects at the neighbor scale. Experimentally altering field arbuscular mycorrhizal fungal associations by silencing the Sym-pathway gene NaCCaMK did not affect reproductive overyielding, implicating an effect independent of belowground AMF interactions. Additionally, micro-grafting experiments revealed dependence on shoot-expressed MPK4 for N. attenuata to vary its yield per neighbor presence. We find that variation in a single-gene, MPK4, is responsible for population overyielding through a mechanism, independent of irMPK4's WUE phenotype, at the aboveground, population scale.
Data availability
The datasets used in the final fittings of our linear (LM), generlized least-squares (GLS), or linear mixed effects (LME/R) models, from which statistical significances were extracted, are included as "Source Data" files in our submission. Each Source Data file refers to the figure in which the corresponding data/results are displayed.
Article and author information
Author details
Funding
Max-Planck-Gesellschaft
- Erica McGale
- Henrique Valim
- Deepika Mittal
- Jesús Morales Jimenez
- Rayko Halitschke
- Meredith C Schuman
- Ian T Baldwin
European Research Council (Advanced Grant 293926)
- Henrique Valim
- Meredith C Schuman
- Ian T Baldwin
iDiv
- Erica McGale
- Henrique Valim
- Meredith C Schuman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, McGale et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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