|LAHNER, BRET - Purdue University
|MICKELBART, MICHAEL - Purdue University
|SALT, DAVID - University Of Aberdeen
Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/27/2013
Publication Date: N/A
Interpretive Summary: The ionome, or elemental profile, of a maize kernel represents at least two distinct ideas. First, the collection of elements within the kernel are critical components of food, feed, and feedstocks for people, animals, and industrial processes, respectively. Second, the ionome of the kernel represents a readout of the genetic program of the plant, the environment that it grows in, and the interaction between them. The ability to understand how these factors interact can lead to new knowledge about how plants adapt to their soil environment, allowing for improvement in crop productivity with less fertilizer and on more land. Many chemical analysis methods rely on grinding of multiple kernels and analyzing the resulting powder, a time and labor intensive process. Using single, unground kernels as the sample has many advantages in terms of speed and the ability to automate procedures, but there have been concerns that this will introduce artifacts that obscure the relevant signals. We have shown that single kernel analysis is capable of detecting genetic and environmental effects on the maize kernel ionome and that potential artifacts, although detectable, are not large enough to prohibit analysis. This demonstrates that a high throughput elemental profiling platform based on single kernel analysis can be used for large genetics experiments in maize.
Technical Abstract: The ionome, or elemental profile, of a maize kernel represents at least two distinct ideas. First, the collection of elements within the kernel are food, feed and feedstocks for people, animals and industrial processes. Second, the ionome of the kernel represents a developmental end point that can summarize the life history of a plant, combining genetic programs and environmental interactions. We assert that single kernel based phenotyping of the ionome is an effective method of analysis, as it represents a reasonable compromise between accuracy, efficiency and power. Here we evaluate potential pitfalls of this sampling strategy using several field grown maize sample sets. We demonstrate that there is enough genetic diversity in elemental accumulation to overcome potential artifacts, and that environmental signals are also detectable. We conclude that using single seeds as the sampling unit is a valid approach for understanding genetic and environmental effects on the maize kernel ionome.