Glutathione treatment suppresses the adverse effects of microplastics in rice

Oryza sativa is grown worldwide and exhibit sensitivity to different stresses. Exponential increase in microplastics in agroecosystems is damaging and demand pragmatic strategies to protect growth and yield losses. We evalu-ated exogenous application of different doses of glutathione (GSH) for mediation of physiological traits of rice plants experiencing two different MPs i.e. PET and HDPE in root zone. All the rice seedlings exhibited MP -induced significant (P <= 0.001) growth inhibition compared to the control plants. GSH application (T3) significantly increased the shoot fresh weight (8.80%), root fresh weight (19.22%), shoot dry weight (13.705%), root dry weight (25.52%), plant height (5.75%) and 100-grain weight (9.36%), compared to control plants. GSH treated plants (T4) showed a recovery mechanism by managing the marginal rate of reduction of all photosyn-thetic and gas exchange attributes by showing 34.44, 20.98, 34.83, 42.16, 39.70, and 51.38% reduction for Chl-a, Chl-b, total cholophyll, photosynthetic rate (A), transpiration rate (E), and stomatal conductance (Gs), respectively, compared to control plants. Under 5 mg L-1 HDPE and PET, rice seedlings without GSH treatment responded in terms of increase in total soluble sugar, total free amino acid, glutathione, glutathione disulfide contents, while total soluble protein and ascorbic acid contents decreased significantly, compared with control plants. Corrleation matrix revealed positive relationship between GSH and improvement in studied attributes. Moreover, exogenous GSH improved rice growth and productivity to counter the negative role of MPs. This unique study examined the effects of GSH on rice plants growing in MP-contaminated media and revealed how exogenous GSH helps plants survive MP-stress.

Automated summary

Oryza sativa is sensitive to different stresses and microplastic contamination in agroecosystems is increasing. This study found that the application of exogenous glutathione (GSH) can improve the physiological traits of rice plants under different microplastic pressures. GSH treatment enhances rice plant growth and productivity, counteracting the negative effects of microplastics.