Stress salinity

Ramagopal, S. (1987). Differential mRNA transcription during salinity stress in barley. Proceedings of the National Academy of Sciences, USA, 84, 94-8. 

Salinity is another major limiting factor in agriculture affecting a large area of cultivated land, and with increasing irrigation salinity stress has become more widespread. In recent years there has been increased interest... 

Cells exposed to saline stress encounter reduced water availability, ion toxicity and reduced availability of essential nutrients. These cellular level responses are also reflected at the whole-plant level. An understanding of these cellular responses will undoubtedly contribute to an understanding of the response of a plant growing in a saline environment. 

A frequently observed response of plant cells exposed to saline stress is the accumulation of proline. Two cell lines of tobacco, one resistant and the other sensitive to growth inhibition by NaCl, accumulated proline when exposed to 1.5% w/v NaCl in the growth media (Dix Pearce, 1981). The NaCl sensitive line accumulated proline more rapidly than did the resistant line, though the levels accumulated were not adequate to provide osmotic protection against salt stress. The authors suggested that proline accumulation may have a protective role other than osmoregulation and may be symptomatic of stress injury, the nature of which was not discussed. 

Aspinall, D. (1986). Metabolic effects of water and salinity stress in relation to expansion of the leaf surface. Australian Journal of Plant Physiology, 13, 59-73. 

Iraki, N.M., Singh, N., Bressan, R.A., and Carpita, N.C. (1989) Cell walls of tobacco cells and changes in composition associated with reduced growth upon adaption to water and saline stress. Plant Physiol. 91 48-53. 

Li, J., Steen, H., and Gygi, S.P. (2003) Protein profiling with cleavable isotope-coded affinity tag (cICAT) reagents. The yeast salinity stress response. Mol. Cell. Proteomics 2, 1198-1204. 

Weber, R.E., A. de Zwaan, and A. Bang. 1992. Interactive effects of ambient copper and anoxic, temperature and salinity stress on survival and hemolymph and muscle tissue osmotic effectors in Mytilus edulis. Jour. Exper. Mar. Biol. Ecol. 159 135-156. 

Environmentally mediated host predisposition to disease have been linked with obligate pathogen performance, and included exposure to cold (Schulz and Bateman, 1969), low light intensity, or short day lengths (Foster and Walker, 1947), salinity stress (MacDonald, 1982), high temperature (Edmunds, 1964), and drought or moisture stress (Boyer, 1995 Duniway, 1977). 

MacDonald, J.D. Effect of salinity stress on the development of Phytophthora root rot of chrysanthemum. Phytopathology 1982 72 214-19. 

Neumann, P. M., E. van Volkenburgh, and R. E. Cleland, 1988, Salinity stress inhibits bean leaf expansion by reducing turgor, not wall extensibility. Plant Physiol. 88 233-237. 

Possibility of molecular protection of photosynthesis under salinity stress... 

High concentrations of salts (e.g., Na, Cl, and other ions), i.e., salinity stress, have two modes of action, i.e., nonspecific osmotic stress caused by water deficit and specific ion effect resulting from the accumulation of Na and Cl ions, which disturb nutrient acquisition and induce cytotoxicity. Salinity could have several origins soils which lay on geologic marine deposits, proximity of a seashore, and improper water and fertilization management. It is well known that transpiration and evaporation take away water from the soil as vapour, concentrating the minerals in the soil solution. 

Figure 5. The growth response to salinity stress. The solid green line represents the change in the growth rate after the addition of NaCl. (a) The broken green line represents the hypothetical response of a plant with an increased tolerance to the osmotic component of stress, (b) The broken red line represents the response of a plant with an increased tolerance to the ionic component of stress, (c) The green-and-red line represents the response of a plant with increased tolerance to the osmotic and ionic components of stress [83].

Lauchli A., Grattan SR. Plant growth and development under salinity stress. Jenks MA, Hasegawa PM. Jain SM. (ed.) Advances in Molecular Breeding toward Drought and Salt Tolerant Crops. Dordrecht, Netherlands, Springer 2007,1-32. 

Essa TA. Effect of salinity stress on growth and nutrient composition of three soybean (Glycine max L. Merrill) cultivars. Journal of Agronomy and Crop Science 2002 188(20) 86-93. 

Schabes FI., Sigstad EE. Calorimetric studies of quinoa (Chenopodium quinoa Willd.) seed germination under saline stress conditions. Thermochimica Acta 2005 428 71-75. 

Shepard JL, Olsson B, Tedengren M, Bradley BP. Protein expression signatures identified in Mytilus edulis exposed to PCBs, copper and salinity stress. Mar Environ Res 2000 50(l-5) 337-40. 

Hirasawa, T., Nakakura, Y., Yoshikawa, K., Ashitani, K., Nagahisa, K., Furusawa, C., Katakura, Y., Shimizu, H., and Shioya, S. 2006. Comparative analysis of transcriptional responses to saline stress in the laboratory and brewing strains of Saccharomyces cerevisiae with DNA microarray. Appl. Microbiol. Biotechnol. 703,346-357. 

Brassinosteroids (BSs) represent a new group of plant hormones that possess a broad spectrum of physiological activities (1,2). A most Intriguing property of BSs Is their capacity to Increase stress resistance In plants, but the mechanism of such an antistress activity still remains unknown (1). As cell stress resistance Is usually associated with stress protein synthesis (3 4) our aim was to study the BS effect on protein synthesis and ultrastructure of wheat leaf cells at normal temperature and under heat shock conditions. We have also studied the Influence of BSs on mesophyll cell ultrastructure under saline stress. 

Figure 7. Protective effect of 10 M EB on nuclei ultrastructure in barley leaf mesophyll cells under saline stress (0.5 M NaCl). Leaf segments were incubated in Atwater, 26 h B-water, 2 h, +0.5 M NaCl, 24 h C-EB 10 m, 26 h D-EB,10 M, 2h. + ( EB. 10 M + 0.5M NaCI), 24 h. Scale bars, 5 mkm.

BSs protected cereal leaf cells from heat shock or saline stress. Leaf pre treatment with BSs decreased cell ultrastructure degradation from heat shock and high salt conditions. BSs increased HSG formation which is supposed to protect preformed mRNA in plant cells during heating. BSs enhanced heat shook resistance of the leaf protein-synthesizing system. The effect of BSs on RNA and protein synthesis was shown earlier (14). We observed protein synthesis activation in wheat leaves by BSs in normal and under stress conditions. Two-dimensional SDS-FAAGE of dS-methionine labeled proteins demonstrated BS-induced changes in the set of polypeptides synthesized in leaves and in the rate of their synthesis. 

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