Use of Nitric Oxide and Hydrogen Peroxide for Better Yield of Wheat (Triticum aestivum L.) under Water Deficit Conditions: Growth, Osmoregulation, and Antioxidative Defense Mechanism.

Noman Habib,Muhammad Rizwan Shahid,Muhammad Zulqurnain Haider,Rashida Perveen,Amr Elkelish,May Bin-Jumah,Mohamed M Abdel-Daim,Muhammad Tariq Javed,Shafaqat Ali,Qasim Ali,Muhammad Rizwan

doi:10.3390/plants9020285

Abstract

The present experiment was carried out to study the influences of exogenously-applied nitric oxide (NO) donor sodium nitroprusside (SNP) and hydrogen peroxide (H2O2) as seed primers on growth and yield in relation with different physio-biochemical parameters, antioxidant activities, and osmolyte accumulation in wheat plants grown under control (100% field capacity) and water stress (60% field capacity) conditions. During soaking, the seeds were covered and kept in completely dark. Drought stress markedly reduced the plant growth, grain yield, leaf photosynthetic pigments, total phenolic content (TPC), total soluble proteins (TSP), leaf water potential (Ψw), leaf turgor potential (Ψp), osmotic potential (Ψs), and leaf relative water content (LRWC), while it increased the activities of enzymatic antioxidants and the accumulation of leaf ascorbic acid (AsA), proline (Pro), glycine betaine (GB), malondialdehyde (MDA), and H2O2. However, seed priming with SNP and H2O2 alone and in combination mitigated the deleterious effects of water stress on growth and yield by improving the Ψw, Ψs, Ψp, photosynthetic pigments, osmolytes accumulation (GB and Pro), TSP, and the antioxidative defense mechanism. Furthermore, the application of NO and H2O2 as seed primers also reduced the accumulation of H2O2 and MDA contents. The effectiveness was treatment-specific and the combined application was also found to be effective. The results revealed that exogenous application of NO and H2O2 was effective in increasing the tolerance of wheat plants under drought stress in terms of growth and grain yield by regulating plant–water relations, the antioxidative defense mechanism, and accumulation of osmolytes, and by reducing the membrane lipid peroxidation.

Highlights

Wheat is one of the major cereals in the world, being a main source of calories and protein in most parts of the world
Seed priming with sodium nitroprusside (SNP) and H2 O2 separately, as well as their combined application (SNP + H2 O2 ), significantly improved the fresh and dry weights, as well as the lengths of shoots and roots of wheat plants of both cultivars; slightly more improvement was found in plants of cv
H2 O2 seed priming was more effective as compared with other treatments in improving the root fresh and dry biomass and root lengths, while maximum improvement in shoot length was recorded in plants grown from seeds primed with combined application (SNP + H2 O2 ) (Figure 1A,B,E,F; Table 1)

Summary

Introduction

Wheat is one of the major cereals in the world, being a main source of calories and protein in most parts of the world. Water-stress-induced excessive production of reactive oxygen species (ROS), such as singlet oxygen (1 O2 ), hydrogen peroxide (H2 O2 ), superoxide anions (O2 − ), and hydroxyl radical (OH− ), are the important ones that damage the lipids, proteins, photosynthetic pigments, and nucleic acids [4]. Under severe stress, these damages eventually lead to death of cells, and of the plant [5]. Chloroplasts, vacuoles, microbodies, and mitochondria are the organelles or sites for production of ROS [6]

Methods

Results

Conclusion