Magnetopriming Actuates Nitric Oxide Synthesis to Regulate Phytohormones for Improving Germination of Soybean Seeds under Salt Stress

Sunita Kataria; Anjali Anand; Ritesh Kumar Raipuria; Sunil Kumar; Meeta Jain; Anshul Watts; Marian Brestic

doi:10.3390/cells11142174

Magnetopriming Actuates Nitric Oxide Synthesis to Regulate Phytohormones for Improving Germination of Soybean Seeds under Salt Stress

Cells. 2022 Jul 12;11(14):2174. doi: 10.3390/cells11142174.

Authors

Sunita Kataria¹, Anjali Anand², Ritesh Kumar Raipuria³, Sunil Kumar⁴, Meeta Jain¹, Anshul Watts³, Marian Brestic^{5

6}

Affiliations

¹ School of Biochemistry, Devi Ahilya Vishwavidyalaya, Khandwa Road, Indore 452001, India.
² Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.
³ ICAR-National Institute for Plant Biotechnology, New Delhi 110012, India.
⁴ Division of Seed Science and Technology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.
⁵ Institute of Plant and Environmental Sciences, Slovak University of Agriculture, A. Hlinku 2, 94976 Nitra, Slovakia.
⁶ Department of Botany and Plant Physiology, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, 16500 Prague, Czech Republic.

Abstract

In this study, the role of the signalling molecule nitric oxide (NO) in magnetopriming-mediated induction of salinity tolerance in soybean seeds is established. The cross-talk of NO with germination-related hormones gibberellic acid (GA), abscisic acid (ABA) and auxin (IAA) for their ability to reduce the Na⁺/K⁺ ratio in the seeds germinating under salinity is highlighted. Salt tolerance index was significantly high for seedlings emerging from magnetoprimed seeds and sodium nitroprusside (SNP, NO-donor) treatment. The NO and superoxide (O₂^•-) levels were also increased in both of these treatments under non-saline and saline conditions. NO generation through nitrate reductase (NR) and nitric oxide synthase-like (NOS-like) pathways indicated the major contribution of NO from the NR-catalysed reaction. The relative expression of genes involved in the NO biosynthetic pathways reiterated the indulgence of NR in NO in magnetoprimed seeds, as a 3.86-fold increase in expression was observed over unprimed seeds under salinity. A 23.26-fold increase in relative expression of NR genes by the NO donor (SNP) was observed under salinity, while the NR inhibitor (sodium tungstate, ST) caused maximum reduction in expression of NR genes as compared to other inhibitors [L-NAME (N(G)-nitro-L-arginine methyl ester; inhibitor of nitric oxide synthase-like enzyme) and DPI (diphenylene iodonium; NADPH oxidase inhibitor)]. The ratio of ABA/GA and IAA/GA decreased in magnetoprimed and NO donor-treated seeds, suggesting homeostasis amongst hormones during germination under salinity. The magnetoprimed seeds showed low Na⁺/K⁺ ratio in all treatments irrespective of NO inhibitors. Altogether, our results indicate that a balance of ABA, GA and IAA is maintained by the signalling molecule NO in magnetoprimed seeds which lowers the Na⁺/K⁺ ratio to offset the adverse effects of salinity in soybean seeds.

Keywords: germination; growth hormones; magnetopriming; nitric oxide; salt stress; tolerance.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Abscisic Acid / metabolism
Abscisic Acid / pharmacology
Glycine max*
Hormones / metabolism
Nitric Oxide / metabolism
Nitric Oxide Donors / pharmacology
Nitric Oxide Synthase / metabolism
Plant Growth Regulators* / metabolism
Plant Growth Regulators* / pharmacology
Salt Stress
Seeds / metabolism

Substances

Hormones
Nitric Oxide Donors
Plant Growth Regulators
Nitric Oxide
Abscisic Acid
Nitric Oxide Synthase

Grants and funding

The work was supported by the grant received by the first author under the Women Scientists Scheme-A (DST/SR/WOS-A/LS-17/2017) of Department of Science and Technology, New Delhi, India.