# Pea Seed Priming with Pluronic P85-Grafted Single-Walled Carbon Nanotubes Affects Photosynthetic Gas Exchange but Not Photosynthetic Light Reactions

## TL;DR

Treating pea seeds with carbon nanotubes changes gas exchange but not light reactions in photosynthesis, possibly improving drought resistance.

## Contribution

New insights into how carbon nanotubes affect photosynthesis and plant development in primed pea seeds.

## Key findings

- P85-SWCNT seed priming alters seed surface and reduces shoot emergence by 10–19%.
- No changes in photosynthetic apparatus structure or function in 14-day-old plants.
- Reduced stomatal conductance and increased water use efficiency suggest improved drought tolerance.

## Abstract

Nanotechnology is rapidly advancing towards the development of applications for sustainable plant growth and photosynthesis optimization. The nanomaterial/plant interaction has been intensively investigated; however, there is still a gap in knowledge regarding their effect on crop seed development and photosynthetic performance. In the present work, we apply a priming procedure with 10 and 50 mg/L Pluronic-P85-grafted single-walled carbon nanotubes (P85-SWCNT) on garden pea seeds and examine the germination, development, and photosynthetic activity of young seedlings grown on soil substrate. The applied treatments result in a distorted topology of the seed surface and suppressed (by 10–19%) shoot emergence. No priming-induced alterations in the structural and functional features of the photosynthetic apparatus in 14-day-old plants are found. However, photosynthetic gas exchange measurements reveal reduced stomatal conductance (by up to 15%) and increased intrinsic water use efficiency (by 12–15%), as compared to hydro-primed variants, suggesting the better ability of plants to cope with drought stress—an assumption that needs further verification. Our study prompts further research on the stomatal behavior and dark reactions of photosynthesis in order to gain new insights into the effect of carbon nanotubes on plant performance.