Journal Article

Hydrogel-based transparent soils for root phenotyping in vivo

Cademartiri, Ludovico, Ganapathysubramanian, Baskar, Shi, Yichao, Ma, Lin, Egner, Timothy K., Yuan, Bin, Venditti, Vincenzo, Lind, Kara R., Siemianowski, Oskar, Mirnezami, Seyed Vahid

2019

Overview

Root phenotypes are increasingly explored as predictors of crop performance but are still challenging to characterize. Media that mimic field conditions (e.g., soil, sand) are opaque to most forms of radiation, while transparent media do not provide field-relevant growing conditions and phenotypes. We describe here a “transparent soil” formed by the spherification of hydrogels of biopolymers. It is specifically designed to support root growth in the presence of air, water, and nutrients, and allows the time-resolved phenotyping of roots in vivo by both photography and microscopy. The roots developed by soybean plants in this medium are significantly more similar to those developed in real soil than those developed in hydroponic conditions and do not show signs of hypoxia. Lastly, we show that the granular nature and tunable properties of these hydrogel beads can be leveraged to investigate the response of roots to gradients in water availability and soil stiffness.

• Publisher: National Academy of Sciences
• Subject: air / Beads / Biological Sciences / Biopolymers / Culture Media / Engineering / Glycine max - physiology / Hydrogels / Hydrogels - chemistry / Hydroponics / Hypoxia / microscopy / Nutrients / Phenotype / Phenotypes / Phenotyping / Photography / Physical Sciences / Plant Biology / Plant growth / Plant Roots - classification / Plant Roots - physiology / root growth / Roots / sand / soil / Soil - chemistry / Soil conditions / Soil water / Soils / Soybeans / Stiffness / Tissue Culture Techniques / Water availability