# Influence of Methyl Jasmonate and Short-Term Water Deficit on Growth, Redox System, Proline and Wheat Germ Agglutinin Contents of Roots of Wheat Seedlings

## TL;DR

This study shows that methyl jasmonate helps wheat seedlings tolerate drought by reducing oxidative stress and improving root health.

## Contribution

The novel finding is that methyl jasmonate pretreatment mitigates drought stress effects in wheat roots by regulating antioxidants, proline, and wheat germ agglutinin.

## Key findings

- Methyl jasmonate pretreatment reduces oxidative stress markers like O2•− and H2O2 in wheat roots under drought.
- MeJA increases antioxidant enzyme activity and decreases cell death and electrolyte leakage in stressed wheat roots.
- MeJA reduces proline exudation into the medium while maintaining wheat germ agglutinin at control levels during drought.

## Abstract

Drought is a serious environmental problem that limits the yield of wheat around the world. Using biochemical and microscopy methods, it was shown that methyl jasmonate (MeJA) has the ability to induce the oxidative stress tolerance in roots of wheat plants due to the regulation of antioxidant enzymes activity, proline (Pro), and wheat germ agglutinin (WGA) accumulation. During the first hours of 12% polyethylene glycol (PEG) exposure, stress increased the superoxide radical (O2•−) and the hydrogen peroxide (H2O2) accumulation, the activity of superoxide dismutase (SOD), total peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), the percent of dead cells (PDC), malondialdehyde accumulation (MDA), and electrolyte leakage (EL) of wheat roots as compared to the control. Stress enhanced proline (Pro) and wheat germ agglutinin (WGA) contents in roots and the plant’s nutrient medium, as well as decreased the mitotic index (MI) of cells of root tips in comparison to the control. During PEG exposure, 10−7 M MeJA pretreatment increased the parameter of MI, declined O2•− and H2O2 generation, PDC, MDA, and EL parameters as compared to MeJA-untreated stressed seedlings. During 1 day of drought, MeJA pretreatment additionally increased the activity of SOD, total POD, APX, CAT, Pro, and WGA accumulation in wheat roots in comparison to MeJA-untreated stressed plants. During stress, MeJA pretreatment caused a decrease in Pro exudation into the growth medium, while WGA content in the medium was at the control level.