# Within‐Plant Leaf Maturity and Trichome Density Variation Shape the Elemental Composition Divergence in Desert Plant Sand Rice (Agriophyllum squarrosum)

## TL;DR

This study shows how leaf maturity and trichome density affect mineral composition in desert sand rice plants.

## Contribution

The study identifies how trichome density and leaf maturity influence elemental composition in desert sand rice.

## Key findings

- Trichome density declines with leaf maturity, affecting the distribution of 33 mineral elements.
- Sixteen key elements (e.g., S, Ca, Fe, Mn) are primary factors in elemental variance.
- Mineral composition differs between wild-type and trichomeless mutant genotypes and across leaf ages.

## Abstract

Subindividual variation in leaf elemental composition, driven by trichome density and leaf maturity, is critical for plant adaptation but poorly understood in desert species. Here, we reveal that sand rice (Agriophyllum squarrosum), a potential future food crop, exhibits obvious declines in leaf trichome density across developmental stages, significantly influencing the redistribution of 33 mineral elements. The concentrations of these elements varied between genotypes (wild type: Shapotou, SPT; trichomeless1 mutant: astcl1) and/or across leaf ages (top, middle, bottom). Sixteen key elements (e.g., S, Ca, Fe, Mn) were identified as primary factors of elemental variance. Our findings reveal a specific subindividual mineral composition of sand rice influenced by trichome density and leaf maturity, providing insights into adaptive trends in leaf nutrient traits and enhancing our understanding of the strategies plants employ to thrive in barren sandy environments.

The density and adhesion of trichomes vary across different developmental stages. The mineral element profiles also change between the two genotypes (wild‐type SPT and astcl1 mutant) and across different leaf ages, with 16 key elements identified as the main factors influencing these changes.