Wheat seed germination response to novel agar/ι-carrageenan blended hydrogel coating
under drought stress
Maya Hotta1,2, James Kennedy1,3, Clement Higginbotham1 and Noreen Morris1,2
1
Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland
Department of Life and Physical Sciences, Athlone Institute of Technology, Athlone, Ireland
3
Mazars, Harcourt Road, Dublin 2, Ireland
2
Corresponding author: [email protected]
Extreme climate events have increased the frequency and severity of drought in recent years
which has caused extensive crop failures throughout the world. Much research has been carried
out to mitigate drought stress and improve crop productivity by searching drought tolerant
species and developing seed coating materials. ι-Carrageenan is a material extracted from
seaweed that is known to act as a plant growth stimulant1. It also forms a water-absorbent
material (hydrogel) that can retain/release water to alleviate drought stress in plants. A novel
hydrogel seed coating based on a blend of ι-carrageenan and agar was developed in this
project2-4, and assessed as a biodegradable and environmentally friendly coating agent to
enhance seedling growth in drought simulated conditions. This study revealed that the hydrogel
coating on Durum wheat seeds (T. durum) improved speed of germination and overall seed
vigour in comparison to the uncoated seeds. This novel agar/ι-carrageenan blended hydrogel
has shown the potential to work as a natural, non-toxic seed coating material that can enhance
seedling development under less than ideal growth conditions. It is anticipated that this natural
hydrogel seed coating can be applied to different variety of seeds and contribute to future
agriculture and food sustainability.
References:
1. Castro, J., Vera, J., (2012) Oligo-carrageenans stimulate growth by enhancing photosynthesis, basal
metabolism, and cell cycle in Tobacco plants (var. Burley), Journal of Plant Growth Regulation,
31(2): 173–185.
2. Hotta, M., Kennedy, J., Higginbotham, C., Morris, N. (2016) Durum wheat seed germination
response to hydrogel coatings and moisture under drought stress, American Journal of Agricultural
and Biological Sciences, 11(2): 67–75.
3. Hotta, M., Kennedy, J., Higginbotham, C., Morris, N. (2016) Development of seed coating agent
with ι-carrageenan hydrogel for sustainable agriculture, Journal of the Institute of Chemistry of
Ireland, July(3): 36–37.
4. Hotta, M., Kennedy, J., Higginbotham, C., Morris, N. (2014) Synthesis and characterisation of
novel ι-carrageenan hydrogel blends for agricultural seed coating application, Applied Mechanics
and Materials, 679: 81–91.
Pictures:
Uncoated (left) and hydrogel coated (right) Durum wheat seeds. Photographs: © Maya
Hotta
Dry hydrogel (left) swollen after 24 hrs in distilled water (right). Photographs: © Maya
Hotta
Acknowledgements: