Drought stress‐induced changes in the composition and physical state of phospholipids in wheat

Abstract

Seedlings of winter wheat (Triticum aestivum L. cv. Jubilejnaja 50) were grown under normal and dry conditions. Frost resistance (LT50) of 10‐day‐old control seedlings was −6°C. LT50 of the subsequently drought‐stressed leaves shifted to −16°C. In plants of the same physiological age (28 days) but grown without stress, LT50 was −12°C. Phosphatidylcholine accumulated and phosphatidylethanolamine decreased in drought‐stressed leaves. Fatty acid unsaturation of these phospholipids increased with leaf age, independently of water supply. Both ageing and drought stress produced a decrease in the apparent phase separation temperature of isolated total phospholipids as determined by electron spin resonance. The possible role of dehydration‐induced structural changes in the bilayer matrix in triggering adaptive alterations in membrane composition, similar to those observed during cold hardening, is discussed.

Acclimation Changes of Flavonoids in Needles of Conifers during Heat and Drought Stress 2015

“…This finding coincided with a weakening of nuclear membranes by drought damaged phospholipids of wheat [22]. Environmental factors, such as high temperatures above 32˝C were found to promote ageing as well as disordered membrane structures [23].…”

Cryopreservation of spores of vesicular–arbuscular mycorrhizal fungi*

“…Evidently, more than dehydration is occurring as spores are exposed to slowly drying soil which prepares them for freezing. Perhaps metabolic processes which result in the maintenance of the fluidity of membranes, such as increased unsaturation of fatty acids (Levitt, 1980, p. 196), increase in phospholipids (Vigh et al, 1986;Borochov et al, 1987;Lynch & Steponkus, 1987), the maintenance of permeability to water (Mazur, 1969;Levitt, 1980, p. 126), and lipid-sugar interactions (Caflfrey, Fonseca & Leopold, 1988) occur as the soil slowly dries, but not in osmotically active cryoprotectants.…”

Desiccation Tolerance of Papaver dubium L. Pollen during Its Development in the Anther

“…The primary focus of these studies is the behavior of membranes during drought stress, particularly the changes in composition of phospholipids as regulatory to the physical properties of the membrane, and the functioning of enzymes. There are several reports on the similarities between desiccation and freezing tolerance, in that exposure to desiccation stress improves tolerance for freezing (16,29).Sucrose levels have been found to increase during both cold hardening (1,24) and desiccation stress (2). After an initial attention to sucrose as a depressant of the freezing point, researchers lost interest because the elevated sucrose levels could not account for the considerable freezing tolerance found in coldhardened plants.…”

“…The primary focus of these studies is the behavior of membranes during drought stress, particularly the changes in composition of phospholipids as regulatory to the physical properties of the membrane, and the functioning of enzymes. There are several reports on the similarities between desiccation and freezing tolerance, in that exposure to desiccation stress improves tolerance for freezing (16,29).…”