**1. Introduction**

Food is one of the basic needs of every organism including human being to survive hence its importance cannot be exaggerated. Beyond the need to quench appetite, food is extremely essential for optimal functioning of the entire body physiology and metabolism. All requirements meet out by a balanced diet that comprise essential macro and micro nutrients available in several types of food ingredients (i.e., carbohydrates, proteins, lipids, mineral and vitamins, and dietary fibers) consumed as daily meal [1]. Among all the necessary food ingredients, carbohydrates are the key ingredients occurring in balanced diets as a primary source of energy required to perform routine workout and other physical actions. Most of the carbohydrates are supplied by cereal grains of the grassy crops [2]. Cereals which include; rice, wheat, corn, sorghum, pearl millet and small millets have been grown since time immemorial for food, fodder and fuel in crop-livestock based agricultural systems around the world [3]. Most of the cereals have predominantly been considered as a staple foods in every agro-ecology and promoted as a healthy food in body weight management, however each cereal contribute in different ways. Plant based foods in various forms are an essential components in human diets which contain essential ingredients. For instance, millets are high-quality alternative to major cereals (rice, wheat, and maize) owing to their greater minerals and proteins contents. In addition, statistical studies have shown that half of the total percentage of calories consumed by human population comes from cereals which are the most traded agricultural commodity in international markets [4].

Global cereal growing area is projected to increase by 14 million hectares between 2020 and 2030 and harvested area over developed countries projected to grow by 4 million hectares, in Russia, Ukraine and Australia, as well as in developing countries using about 10 million hectares, mainly in Asian and Latin American countries. Arable land area under wheat and corn is expected to be raised by ~3% and 4%, however other areas under coarse grains and rice expected to remain unchanged. As land expansion is constrained by limited arable land accessibility compared to the previous decade, resulting restrictions placed on the conversion of forests or pastures to cropland, and continued urbanization, worldwide production growth is predictable to be driven mostly by intensification. Yield growth due to improved cultivation technology and methods, particularly in developing countries, is predicted to support prospect cereal production. Thus, the upward trend in cereal production observed in recent decades is indicative of the progress made in the agricultural sector around the world (**Figure 1**). Global yields are expected to increase between the base period and 2030 by approx 9% for wheat and other coarse grains, 10% for corn and 12% for rice. World wheat production is anticipated to hike by 87 million tons to 840 million tons by 2030, a moderate pace in relative terms compared to the past decade. India is the world's third-largest wheat producer, expected to provide the largest share of additional wheat supplies, boosting production by 18 million tonnes by 2030 and expanding acreage in response to a national policy to increase self-sufficiency in wheat. Nevertheless, consumption of the cereal grains is greater than the production; hence a higher cereal production with improved nutritional values will need to meet out increasing demands due the burgeoning population. Global cereal production predicted to be lesser than consumption requirements in future due to several environmental stresses in the wake of climate change that may lead to drawdown in cereal stock globally.

Among all the cereal, rice (*Oryza sativa*) is major staple food grain belongs to family *Poaceae* worldwide and has extensive economic importance. Rice provides feed *Achieving Salinity-Tolerance in Cereal Crops: Major Insights into Genomics-Assisted Breeding… DOI: http://dx.doi.org/10.5772/intechopen.112570*

#### **Figure 1.**

*Bar diagram illustrating the year wise production and consumption of cereal grains globally.*

to more than 50% of world's population predominantly in Asia where the population is expected to rise from 4.3 to 5.2 billion by 2050. Wheat (*Triticum aestivum L.)* is the second most important staple cereal crop grown all over the world contributing substantially to the world's food and nutritional security world [5]. About 20–30% daily calorie intake [6] and 55% of carbohydrates are provided by wheat worldwide [7]. Wheat bread has high vitamins B, thiamine, and B2-riboflavin content with other several minor nutrients [8]. Worldwide estimated annual production of wheat is about 768.90 million metric tons whereas; India's contribution is about 107.6 million metric tons [9]. Maize (*Zea mays*) is a cereal grain belongs to family Poaceae, cultivated throughout the world. The maize production globally in the year 2020–2021 was 1.2 billion tonnes led by India with 30.2 million metric tonnes [9]. Maize is a staple food plays an important role in food and nutritional security worldwide. Sorghum (*Sorghum bicolar*) is a cereal crop used for grain, fiber and fodder. Sorghum is cultivated in warmer climates worldwide and nutritional profile includes several minerals like phosphorous, iron zinc and copper it is also a good source of b-complex and vitamins. It estimated that the world sorghum production in year 2021–2022 was 60.32 million tons whereas; India's contribution in total production was 4.7 million tons. Pearl millet (*Pennisetum glaucum L*.) has been widely grown in Sub-Saharan Africa, South Asia and Indian subcontinent. Archeological proof and modern genome sequence analysis showed that pearl millet originated and domesticated about 4000 to 5000 years ago in West Africa [10]. The global millet production in the year 2020– 2021 was 30.5 million metric tonnes led by India with 41% (12.5) million metric tons [11]. Pearl millet is one the most important eco-friendly field crop in conventional farming system, plays an important role in food and nutritional security [3].

However, multiple types of environmental stresses (abiotic and biotic) are affecting holistic growth and plant health which ultimately leads to low crop productivity globally. Among the abiotic stresses, soil salinity or salt stress is one the most brutal environmental stresses adversely affecting sustainable crop yield and productivity globally. Hence, a comprehensive research on abiotic stresses in cereals has been experienced to cope with such a crucial salinity problem and related breakthroughs have been conducted and proved to be as one of the key activities to obtain higher genetic gains in terms of adaptability in changing climatic scenarios. Salinity adversely impacts on plant growth and development by exerting ion cytotoxicity, osmotic shock, nutrient imbalance, and oxidative stress [12]. The influence of soil salinity leads to impaired plant physiology, biochemistry and metabolism, hormonal imbalance, and regulatory pathways at cellular or entire plant structure. Plants response to the access salt stress comprised of several physiological and molecular approaches operates in cells in a coordinated fashion to cope with ion toxicity and hyperosmolarity [13]. A plenty of conventional as well as advanced molecular approaches have been developed and employed to breed the salinity tolerant varieties of the different cereal crops [14].
