Water Deficit Irrigation Impacts on Antioxidant Metabolism Associated with Freezing Tolerance in Creeping Bentgrass

Abstract

<jats:p>Soil water deficit impacts cold acclimation and freezing tolerance in creeping bentgrass (<jats:italic>Agrostis stolonifera</jats:italic> L.), but the mechanisms underlying have not been well understood. The objectives of this study were to investigate the effects of deficit irrigation before and during cold acclimation on osmoprotectants, antioxidant metabolism, and freezing tolerance in creeping bentgrass. The grass was subjected to three-soil moisture levels: well-watered [100% container capacity (CC)], deficit irrigation induced-mild drought stress (60% CC), and severe drought stress (30% CC) for 35 days including 14 days at 24/20 °C (day/night) and then 21 days under cold acclimation treatment (2 °C) in growth chambers. Leaf proline and total soluble sugar (TSS) levels were higher in the grass under mild drought stress relative to that under severe drought stress. Superoxide (O<jats:sub>2</jats:sub><jats:sup>−·</jats:sup>), hydrogen peroxide (H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub>), and malondialdehyde (MDA) content were higher in the grass under severe drought relative to that under well-watered and mild drought stress at day 35. Mild drought stress increased catalase (CAT) and guaiacol peroxidase (POD) activity, induced new isoforms and increased band intensities of superoxide dismutase (SOD), CAT, and POD during cold acclimation (days 14 to 35). No differences in osmoprotectants, antioxidant metabolism, and freezing tolerance were found between mild drought and well-watered treatments. The results of this study suggest deficit irrigation-induced mild drought stress in late fall and winter could induce accumulation of osmoprotectants and improve antioxidant metabolism, and freezing tolerance, but severe drought stress could reduce freezing tolerance of creeping bentgrass in the region with limited precipitation.</jats:p>

Plastic response of Medicago sativa L. root system traits and cold resistance to simulated rainfall events

“…2 ). Simultaneously, the cross acclimation of drought and low temperature has been confirmed in creeping bentgrass ( Agrostis stolonifera L.) ( Zhang et al, 2015 ) and alfalfa ( Xu et al, 2020b ), which provides theoretical support for improving cold resistance of alfalfa by water management. To further understand the relationship between water and cold resistance, we conducted a PCA analysis among root system traits and semi-lethal temperature ( Fig.…”

“…Starch can be hydrolyzed into soluble sugar to improve the cold tolerance of alfalfa (Sengupta et al, 2015). In phase 2, the Pro and soluble sugar content of D 8 was still higher than that of the other two cultivars, which indicated that cold acclimation would maximize the cold resistance of alfalfa, but also that a longer irrigation interval can accelerate this process (Xu et al, 2020a;Zhang et al, 2015).…”

“…Appropriate cultivation measures are also an effective way to improve cold resistance. Water plays an important role in the winter hardiness of alfalfa because freezing injury is mainly caused by cell dehydration ( Xu et al, 2020a ; 2020b ; Zhang et al, 2015 ). Water can not only affect the cold resistance of alfalfa by changing the morphology and spatial distribution of the root system, but also protect cells from low-temperature damage through physiological metabolic pathways ( Castonguay et al, 2006 ).…”

PacBio single-molecule long-read sequencing shed new light on the complexity of the Carex breviculmis transcriptome

“…Proline content was examined using the 5-sulfosalicylic acid method, as described in a previous report [40]. Soluble sugar content was measured by the anthrone sulphuric acid method [45]. Photochemical efficiency, including Pn, Ci, Cd, and Tr was estimated using the 6400XT system (Li-Cor, Lincoln, USA) according to the instructions provided by the manufacturer.…”

Drip Irrigation Depth Alters Root Morphology and Architecture and Cold Resistance of Alfalfa

“…Water is a crucial factor that affects the success of alfalfa overwintering because changes in soil moisture content have a greater impact on herbaceous plants [4,5]. On the one hand, sufficient water during the growth period promotes root development and storage of substances for energy; on the other hand, lower intracellular water content in winter reduces the freezing point [6], and freezing injury is mainly caused by cell dehydration [7,8]. Water not only affects the cold resistance of alfalfa by changing the root morphology and architecture, but also protects cells from low-temperature damage through physiological and metabolic pathways [9].…”