Influence of osmoregulators on plant tolerance to water stress

Abstract

CitationDawood MG. 2016. Influence of osmoregulators on plant tolerance to water stress, 13 (1), 42-58. Retrieved from www.pscipub.com (DOI: 10.15192/PSCP. SA.2016.13.1.4258) This article highlights on some recent researches, which studied the impact of osmoregulator compounds and their application on the plant in order to increase the plant tolerance to water stress. Water stress limits the growth, productivity and quality of agricultural crops in the world. Water Stress is not only due to the scarcity of water but also due other factors such as salinity, high temperatures and severe cold that make plants not able to absorb enough water from soil to grow well and this is called physiological drought that leads to a series of disorders in physiological and biochemical processes mainly due to lack of osmotic (internal water content of the plant deficiency), and the toxicity of salt ions. One way to overcome the negative impact of water stress on plants is the use of osmoregulators compounds formed by the plant when exposed to stress such as glycinebetaine, proline and trehalose. Osmoregulator compounds mainly regulate osmotic pressure within the plant to be able to absorb water and also have influential and effective roles on a lot of vital processes in the plant. they protect membranes of chloroplasts and thus increase the photosynthesis efficiency and have the ability to protect cell walls and membranes, which leads to stability and the organization of permeability and play an important role in scavenging the free radicals thus lead to mitigate the adverse impact of stress and improve growth, productivity and quality of plants. It can be concluded from this article that the best material used to increase plant tolerance to water stress is glycinebetaine where it can be obtained in large quantities and at low prices, making use it appropriately in economic terms as well as effective impact on increasing the tolerance of plants to water stress and reflected in increasing crop quantity and quality. Moreover, the use of proline has also an influential and effective role in increasing plant tolerance to water stress, but more expensive than glycinebetaine. Trehalose is an efficient protectant against water deficit conditions, and it is also effective in reducing oxidative stress but trehalose considered the most expensive, until now. We must intensify efforts to study and understand more of the physiological and biochemical changes played by these substances within the plant under stress conditions to improve plant productivity under water stress with modest economic cost.

The role of exogenous glycinebetaine on some antioxidant activity of non-T and T tobacco (Nicotiana tabacum L.) under in vitro salt stress

“…Similar to our findings, the reduction of MDA and H 2 O 2 contents were also observed in some plants using GB(El-Samad et al, 2011;Nawaz & Ashraf, 2007;Yamada et al, 2009). It was observed that compatible solutes such as Pro and GB had an important role in osmotic adjustment and protection of proteins, mitochondria, and chloroplast membranes under salt stress (Dawood, 2016;Takabe et al, 2006). Therefore, modification of negative effects of salinity by GB might be due to its protective role and antioxidant capacity against oxidative stress (Park et al, 2004).…”

Tissue Tolerance Coupled With Ionic Discrimination Can Potentially Minimize the Energy Cost of Salinity Tolerance in Rice

“…Synthesis of such osmolytes via complex biosynthetic pathways not only utilizes huge C-skeleton but also incurs high energy cost. From ATP utilization's point of view, biosynthesis of GB is the least-energy-intensive process, whereas biosynthesis of trehalose requires maximum energy (Dawood, 2016). Interestingly, under saline condition, elemental sodium itself can serve as an osmolyte and aid in maintaining the osmotic potential (Yeo and Flowers, 1986;Glenn et al, 1999;Chakraborty et al, 2016b).…”

Rhizobacteria-induced systemic tolerance against drought stress in Sorghum bicolor (L.) Moench

“…The phenolic compounds that were upregulated in S. bicolor plants under drought stress post treatment with each of the five selected rhizobacterial isolates included the hydroxycinnamic acids and -conjugates: caffeoylshikimate, caffeoylquinate, coumaroylquinate, hesperetin, hydroxyflavone, luteolin, naringenin, 1-Osinapoyl-beta-D-glucose and shikimic acid; the flavonoids quercetin, hesperetin, hydroxyflavone, luteolin and naringenin; the terpenoids loganin and secologanin; and the terpenoid quinones menaquinol, benzoquinol and ubiquinone (Karuppanapandian et al, 2011;Martinez et al, 2016). The group of osmolytes that were upregulated in primed S. bicolor plants included the amino acids proline (Szabados and Savouré, 2010), glutamic acid (Tari et al, 2013); and the amine choline (Dawood, 2016). Choline plays a critical role in plant stress resistance, mainly for enhancing glycine betaine synthesis and accumulation and improved leaf RWC.…”