Roles of glycine betaine in mitigating deleterious effect of salt stress on lettuce (Lactuca sativa L.)

• Published in: Archiv für Acker- und Pflanzenbau und Bodenkunde Vol. 61; no. 12; pp. 1673 - 1689
• Main Authors: Yildirim, Ertan, Ekinci, Melek, Turan, Metin, Dursun, Atilla, Kul, Raziye, Parlakova, Fazilet
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 02.12.2015; Taylor & Francis Ltd
• Subjects: Acetic acid; glycine betaine; growth; hormone; Hydrogen peroxide; Lactuca sativa; Leaves; Peroxidation; Salinity; salt stress; Salts; Sodium chloride; soluble sugars; Stomatal conductance; Vegetables; Water content
• ISSN: 0365-0340; 1476-3567
• DOI: 10.1080/03650340.2015.1030611

This study was conducted to evaluate the roles of glycine betaine (GB) in mitigating deleterious effect of salt stress on lettuce. Lettuce plants were subjected to two salinity (0 and 100 mmol l −1 NaCl) and four GB levels (0, 5, 10, 25 mmol l −1 ). Salinity resulted in a remarkable decrease in growth parameters, relative leaf water content and stomatal conductance. Plants subjected to salt stress exhibited an increase in membrane permeability (MP), lipid peroxidation (MDA), leaf chlorophyll reading value, H 2 O 2 and sugar content. Exogenous foliar applications of GB reduced MP, MDA and H 2 O 2 content in salt-stressed lettuce plants. Salt stress increased Na and generally decreased other nutrient elements. GB reduced Na accumulation, but significantly increased other element contents under salinity conditions. The study showed that gibberellic acid (GA) and salicylic acid (SA) content in salt-stressed plants were lower than those of nonstressed plants. However, salinity conditions generally increased the abscisic acid content. GB treatments elevated the concentrations of GA, SA and indole acetic acid (IAA) at especially 10 and 25 mmol l −1 GB under salt stress conditions. It could be concluded that exogenous GB applications could ameliorate the harmful effects of salt stress in lettuce.