Priming with a Seaweed Extract Strongly Improves Drought Tolerance in Arabidopsis.

Fiaz Rasul,Saurabh Gupta,Bernd Mueller-Roeber,Tsanko Gechev,Justyna Jadwiga Olas,Neerakkal Sujeeth

doi:10.3390/ijms22031469

Abstract

Drought represents a major threat to plants in natural ecosystems and agricultural settings. The biostimulant Super Fifty (SF), produced from the brown alga Ascophyllum nodosum, enables ecologically friendly stress mitigation. We investigated the physiological and whole-genome transcriptome responses of Arabidopsis thaliana to drought stress after a treatment with SF. SF strongly decreased drought-induced damage. Accumulation of reactive oxygen species (ROS), which typically stifle plant growth during drought, was reduced in SF-primed plants. Relative water content remained high in SF-treated plants, whilst ion leakage, a measure of cell damage, was reduced compared to controls. Plant growth requires a functional shoot apical meristem (SAM). Expression of a stress-responsive negative growth regulator, RESPONSIVE TO DESICCATION 26 (RD26), was repressed by SF treatment at the SAM, consistent with the model that SF priming maintains the function of the SAM during drought stress. Accordingly, expression of the cell cycle marker gene HISTONE H4 (HIS4) was maintained at the SAMs of SF-primed plants, revealing active cell cycle progression after SF priming during drought. In accordance with this, CYCP2;1, which promotes meristem cell division, was repressed by drought but enhanced by SF. SF also positively affected stomatal behavior to support the tolerance to drought stress. Collectively, our data show that SF priming mitigates multiple cellular processes that otherwise impair plant growth under drought stress, thereby providing a knowledge basis for future research on crops.

Highlights

Introduction iationsClimate change represents a major threat to food security and can negatively affect crop yields [1,2]
To determine whether pretreatment of plants with Super Fifty (SF) as a priming agent can induce tolerance against drought stress, a drought experiment was performed using Arabidopsis as a model, following the protocol shown in Supplementary Figure S1
Control plants started wilting after 8 days of continuous drought, and symptoms were more pronounced after 11 days of stress (Figure 1a)

Summary

Introduction

Climate change represents a major threat to food security and can negatively affect crop yields [1,2]. Environmental factors such as drought and heat significantly reduce terrestrial net primary production [3,4,5,6]. Global losses in crop production due to drought totaled approximately USD 29 billion between 2005 and 2015 [7]. A combination of bioengineering [8] and other sustainable treatment technologies is required to boost agricultural yields despite increased drought and water scarcity. Treatment technologies using “biostimulants” may potentially fine-tune drought response pathways while preserving yield in agriculture [9]. According to the European Biostimulants Industry Council (EBIC), a biostimulant, Licensee MDPI, Basel, Switzerland

Methods

Results

Conclusion