Introgression of halophytic salt stress-responsive genes for developing stress tolerance in crop plants.

Abstract

The world's population is increasing daily, with corresponding demands for sustainable food production, but about 800 million ha of land is affected by salt. Salinization is gradually increasing for several reasons, including scanty rainfall, poor irrigation practices, salt ingression and natural calamities. Salinity is considered a major abiotic stress that adversely affects the growth and productivity of crop plants. Commonly, crop plants are salt sensitive (glycophytes) and so cannot grow in the salt-affected areas. Some plants have natural ability to grow in the high saline areas and are known as halophytes. Halophytes require salt to complete their life cycle and are thus considered potential sources for salt-responsive genes and promoters. The salt-tolerance mechanism is a very complex process which is coordinated from stress perception to signal transduction, and thus provides stress endurance. Several potential salinity-stress responsive and tolerance genes have been isolated from halophytes, functionally characterized and explored for developing transgenic crop plants for sustainable agriculture in the salt-affected areas. About one-quarter of the entire Arabidopsis genome responds to salt stress, and so the search continues for promising stress-responsive genes that can modulate physiological traits and metabolic pathways without imposing yield penalties. This chapter focuses on the examination of halophytes for salt-responsive genes, their functional validation and further utilization to engineer crop plants.

Ion homeostasis for salinity tolerance in plants: a molecular approach

“…Activation of vacuolar H + ‐ATPases (Conde et al 2011) and H + pyrophosphatases (Dabbous et al 2017) acts as a driving force for ion extrusion from saline toxic cells. Similarly, VATPase transcripts are increased under saline stress conditions leading to entrapment of excess Na + inside the plant vacuoles (Jha et al 2019). The transporters HAK/KT/KUP are expressed in many salt stress‐tolerant plant species and are involved to enhance K + absorption and reducing Na + accumulation inside the cells (Basu et al 2020).…”

Plant growth promoting rhizobacterium Stenotrophomonas maltophilia BJ01 augments endurance against N2 starvation by modulating physiology and biochemical activities of Arachis hypogea

“…Salt interrupts the soil nutrient balance which ultimately affects the growth of plant [5]. Halophytes have the ability to grow under high saline areas and are considered a rich source of metabolites [6, 7], oligosaccharides [8], proteins [9], genes [10–22], promoters [23–25] and renewable energy [26].…”

Proteomics Revealed Distinct Responses to Salinity between the Halophytes Suaeda maritima (L.) Dumort and Salicornia brachiata (Roxb)

“…Numerous studies are being performed in diverse halophytes to understand and identify the genes responsible for salt tolerance [14,15]. Despite various salt stress-responsive genes have been reported, a complete understanding of salt tolerance mechanism still remains elusive.…”