Response characteristics of highland barley under freeze-thaw, drought and artemisinin stresses

Abstract

The freeze-thaw of early spring in China’s Qinghai-Tibet Plateau is often accompanied by severe droughts. Artemisia annua, widely distributed in China, releases allelopathic substances, mainly artemisinin, to the environment and exerts a wide range of effects on crops. This paper studied the physiological effects of highland barley under freeze-thaw, drought, and artemisinin stress through indoor simulation experiments. The physiological response characteristics of superoxide dismutase (SOD) activity, catalase (POD) activity, net photosynthetic rate, relative water content (RWC), relative electrical conductivity, malondialdehyde (MDA) content, and soluble protein content in highland barley were analyzed. The results showed that artemisinin and drought contributed to the increase of SOD activity and the decrease of POD activity. Under the freeze-thaw stress, the SOD and POD activities both decreased firstly and then increased, but the effect of compound stress on POD was more complicated. Either artemisinin, drought, or low temperature could reduce the net photosynthetic rate of highland barley. Low temperature had more significant impacts on photosynthesis, and compound stress would show a single stress superimposed effect. Artemisinin, drought, and low temperature could reduce the RWC of highland barley, and increase the relative electrical conductivity and the concentration of soluble protein (except for low temperature stress above zero, which reduces the concentration of soluble protein). However, the effect of compound stress on soluble protein is more complex. The single stress of artemisinin and drought had no obvious effect on MDA content, while the MDA content was increased significantly under the freeze-thaw stress and the compound stress of artemisinin and drought, and the MDA content reached its peak at T1. The results are helpful to explore the effects of freeze-thaw, drought and artemisinin stress on the growth of highland barley under the background of the aridification of the Qinghai-Tibet Plateau, and provide ideas for rational agricultural management.

Transcriptome Profiling of Stem-Differentiating Xylem in Response to Abiotic Stresses Based on Hybrid Sequencing in Cunninghamia lanceolata

“…Plants constantly monitor and cope with fluctuating environments, such as drought, cold, salinity stress, and so on [51]. Drought contributed to the increase in soluble protein and SOD activity and the decrease in POD activity but had no obvious effect on MDA content in highland barley [52]. In this study, the PEG treatment decreased the soluble protein content and SOD, and increased POD after eight hours (Figure 1).…”

“…Brassica napus [55] and highland barley [52] have their own specific response characteristics of physiological tolerance in different climatic regions with different temperatures. In C. lanceolata, the short-term cold treatment did not cause any significant changes in the soluble protein content, MDA, and POD, and only significantly increased SOD at 8 h of cold treatment (Figure 1).…”

Genome-wide characterization of LEA gene family reveals a positive role of BnaA.LEA6.a in freezing tolerance in rapeseed (Brassica napus L.)

“…The phenotypic change of B. napus were photographed, and the survival rate was counted. The relative electrical conductivity contents were detected by the method according to provious study [ 36 ]. Three replicates were performed for each sample.…”

Enhancing Drought Tolerance and Fruit Characteristics in Tomato through Exogenous Melatonin Application

“…Under drought stress, tomato seedlings quickly developed a lot of reactive oxygen species, and the accumulation of reactive oxygen species was intensified, the degree of membrane lipid peroxidation was increased, membrane permeability was changed, cell physiological function was disturbed, and, finally, cell death was caused [49]. Relative conductivity and MDA can be utilized to assess the degree of membrane peroxidation and damage [50]. In this study, melatonin reduced reactive oxygen species, relative conductivity, and malondialdehyde content under drought stress, indicating that melatonin alleviated membrane damage in seedlings.…”