Hydrogen Sulfide Enhances Plant Tolerance to Waterlogging Stress

Abstract

Hydrogen sulfide (H₂S) is considered the third gas signal molecule in recent years. A large number of studies have shown that H₂S not only played an important role in animals but also participated in the regulation of plant growth and development and responses to various environmental stresses. Waterlogging, as a kind of abiotic stress, poses a serious threat to land-based waterlogging-sensitive plants, and which H₂S plays an indispensable role in response to. In this review, we summarized that H₂S improves resistance to waterlogging stress by affecting lateral root development, photosynthetic efficiency, and cell fates. Here, we reviewed the roles of H₂S in plant resistance to waterlogging stress, focusing on the mechanism of its promotion to gained hypoxia tolerance. Finally, we raised relevant issues that needed to be addressed.

Keywords: gas signaling molecule; hydrogen sulfide; hypoxia tolerance; reactive oxygen species; waterlogging.

Figure 1

Synthesis of H₂S in plant cells [15]. APS: 5’-adenylylsulfate; SIR: sulfite reductase. OAS: O-acetyl serine; OAS-TL: O-acetyl-L-serine (mercaptan) lyase; ASE: acetate; Cys: cysteine.

Figure 2

H₂S plays a pivotal role in sulfur metabolism in plants. Sulfur elements needed for sulfur metabolism in plants are mainly absorbed by roots in the manner of SO₄²⁻ from the soil, which was transported to various parts of plants through microtubules to participate in the process of sulfur metabolism in plants. Another complementary pathway is the absorption of H₂S, carbonyl sulfide (COS), and SO₂ from the air through stomata on the leaves, thus immobilization of sulfur into the sulfur metabolic pathway in plants. CA: carbonic anhydrase, SiR: sulfite reductase.

Figure 3

Schematic diagram of H₂S enhancing the activity of antioxidant system to acquire the tolerance to waterlogging-induced hypoxia.

Figure 4

The role of H₂S in the regulation of waterlogging stress in plants.