Recovery of root growth and physiological characters in cotton after salt stress relief

Abstract

Crop growth in a saline environment depends on its tolerance to salt stress and capacity to recover after salt stress relief. To evaluate recovery mechanisms in cotton after salt stress relief, the changes of plants growth, root vigor, lipid peroxidation, antioxidant enzymes activity, organic solutes in root after salt stress relief were studied for two cotton (Gossypium hirsutum L.) cultivars (Lumianyan 37 and Sumian 22) grown under control (salt content of soil grown cotton was maintained at 0.2%), salt stressed (salt content of soil grown cotton was maintained at 0.5%) and salt recovered (salt content of soil grown cotton was reduced from 0.5% to 0.2% level at the 57 d after seeding) conditions. The results showed that root and shoot growth rate and root vigor significantly increased after salt stress relief, and the increase in growth rate and root vigor was more pronounced in 'Lumianyan 37'. In salt-recovered root, malondialdehyde (MDA) content decrease, the activities of superoxide dismutase (SOD) and peroxidase (POD) decreased, but catalase (CAT) activity increased compared with those in the salt-stressed root. For salt-recovered root, MDA content and POD activity of 'Lumianyan 37' was lower, while the SOD and CAT activities were higher. Salt-recovered cotton root showed a decrease in soluble sugar and free amino acid content compared with the salt-stressed root, especially in 'Lumianyan 37'. The results indicated that growth and root metabolism of cotton plants gradually recovered after salt stress relief, and the high capacity of cotton plants to recover after salt stress relief may be related to the high capacity of antioxidative system and the high utilization capacity of organic solutes as important nutritional components in root.

Comparative Analysis of Physiological, Enzymatic, and Transcriptomic Responses Revealed Mechanisms of Salt Tolerance and Recovery in Tritipyrum

“…These results were in accordance with those of Basal et al who observed a reduction in SDW and RDW with increasing salt levels in salt-tolerant and salt-sensitive cotton varieties (Basal et al, 2006). Moreover, the findings of Guo et al corroborate our results and state that under salt stress, the dry matter accumulation rate of cotton varieties decreases, but it can be resumed in the salt-tolerant varieties after recovery (Guo et al, 2015).…”

“…The growth of crops under salt stress depends on their salt tolerance and resilience after the recovery ( Guo et al, 2015 ). Our analysis of the growth indices indicated an inhibitory effect of salt stress in “CS” at the R2 stage, which was significantly less in “Y1805,” especially in roots ( Figure 3 ).…”

Seed Priming With Melatonin Promotes Seed Germination and Seedling Growth of Triticale hexaploide L. Under PEG-6000 Induced Drought Stress

“…Notably, 100 μM MT priming also increased the root growth rate and length in tomato ( Liu et al, 2015a ). Furthermore, MT has been shown to promote root development under abiotic stresses like salt stress ( Guo et al, 2015 ). In this study, MT treatment increased the root length, root projarea, root surface area, and root volume by 36.34, 28.52, 28.52, and 21.56%, respectively, compared with CK under DS (40–45%).…”

Sewage sludge application enhances soil properties and rice growth in a salt-affected mudflat soil

“…Other studies have found that the application of sewage sludge can increase the root vitality of rice 39 , and ryegrass 37 . The soluble sugar and amino acid contents in the bleeding sap of the plant roots are important indicators of the root penetration potential of the plant 40,41 . This study confirmed that the application of SS increased the soluble sugar and amino acid content in the bleeding sap of rice roots.…”