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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

studied to determine the contribution of various sRNAs in salt tolerance, as

well as the molecular basis of salt stress regulation in plants. Advancement of

computational Biology and innovation of various tools of Bioinformatics also

accelerates the genome-wide identification of these sRNAs, as well as their

targets. Various researchers are trying to use the sRNAs mediated RNA inter­

ference approach for the development of resistant varieties of various crops

for combating soil salinity as well as other abiotic stresses. In this chapter, the

authors have presented the fundamental and applied aspects of small RNA

and RNA interference technology in developing salt-resistant plants.

9.1 INTRODUCTION

Organisms have evolved with a gamut of diverse and sophisticated mecha­

nisms for survival and growth during stressful situations caused by several

biotic and abiotic environmental factors. Plants are primarily sessile organ­

isms, and so they set up multiple layers of protective measures to respond

and resist the surrounding adverse environment (Zhang & Hong, 2019). The

stress response of plants to abiotic and biotic variables has been addressed

in recent decades by employing certain traditional as well as contemporary

breeding methods, which has resulted in crop improvement to some extent.

Extensive understanding of adaptive reactions in the plant to stressful situa­

tions will expedite the development of novel approaches for improving plant

tolerance against stresses (Kumar, 2014). It is well accepted that most of the

plants activate reprogramming of gene expression through regulation at the

transcriptional level or translational level to stimulate defensive mechanisms

for survival under abiotic stress conditions. Among these abiotic variables,

soil salinity is regarded as one of the most detrimental due to its proclivity

to impose constraints on the majority of plants. Accumulation of salt in

the soil has resulted from some natural and anthropogenic activities that

limit the global productivity of crops, as it has been projected that 20% of

global cultivable land is highly affected by salts (Younis et al., 2010). Soil

salinity has a negative influence on growth and development, which can

lead to abnormalities or even early death. There is no doubt that the salt

tolerating cultivars of crop plants have high demand in international markets,

as the majority of the arable land worldwide is gradually getting saline and

dry. To overcome such conditions different research activities are being

carried out on various crop plants by using biotechnological approaches for

pointing out and characterization of different genes under salt stress as well