eChapters

Micronutrients are those elements essential for green plants but required in very small quantity for their growth and development. There are altogether eight micronutrient elements in soil consisting of iron, manganese, zinc, copper, boron, molybdenum and chlorine with the recent addition of nickel. These together with large number of other elements usually present in plants with small concentrations are formed as trace elements. Another element, cobalt is known to be required for microorganisms concerned mainly with nitrogen fixation in legumes affects indirectly the growth of many higher plants, thus, may be considered to be included in the list of essential micronutrient element. Similarly, Vanadium and sodium although present as beneficiary elements for plant growth may also have the possibilities to be enlisted into this group of elements.

Nitrogen Content in Indian Soil Because of tropical and subtropical climates Indian soils have very low nitrogen content and in the majority of cultivated soil it varies from 0.02% to 0.13%. Low levels of N in Indian soil is primarily attributed to climate and secondarily to cropping. Climate plays the dominant role in determining the nitrogen content in soil through the effect of soil organic matter content. Generally heavy textured soils have higher N content than loamy or sandy soils. Other factors remaining the same, total N content in soil decreases with the increase in annual temperature at a given humidity level, on the other hand, it increases with increasing humidity level at a given annual temperature. Maximum N content in soil occurs in the surface layer of soils and decreases with depth in soil profile. The variation of distribution of N content in soil with depth is attributed by varying accumulation of organic matter in soil profile.

The living organisms in the terrestrial ecosystem have unique characteristics of taking up the substances from atmosphere and soil for the synthesis of their own cellular component or as a source of energy. The supply and absorption of chemical compounds required for the growth and metabolism of the organisms may be defined as nutrition and the compounds required by them are called nutrients. The process by which the nutrients are converted to cellular material is known as the metabolism. Out of 118 chemical elements so far detected in the modern periodic table, 92 elements from hydrogen to uranium are naturally occurring, a large portion (more than sixty) of such have been detected in the plant tissues. But, the elements which take part in the nutritional requirement and metabolic processes of the plant are said to be essential elements, others which do not participate in such processes are considered non-essential.

Soil acidity is most conveniently measured by pH of soil suspension with water. Pure water undergoes dissociation into hydrogen and hydroxyl ions and are in equilibrium with undissiociated water molecules Thus, H2 O ??? ??? H+ + OH- (1) and in presence of another H2 O molecule, H+ converts to H3 O+ H+ + H2 O ??? ??? H3 O+ (2) Since water is a weak electrolyte and dissociates as per Eqn. 1, the ionic product of water can be written as – KW = aH+ x aOH- = (CH+ x COH– ) x ( fH+ x fOH-) (3) where, a, C, and f represents the activities, concentrations and activity coefficients of respective ions. In pure water and in dilute solutions the activity coefficients are approximately unity thus the product of concentrations of H+ and OH-1 is the ionic product of water and at ordinary temperature (250 C) this has a constant value of 10-14 gm ions per litre so, Kw =(CH+ x COH–1) = 10-14 gm ion per litre (4) such that, CH+ = COH–1 = 107 gm ion per litre Therefore, if hydrogen ion concentration of an aqueous solution exceeds this value, (10-7gm ion per litre), the solution is said to be acidic then there will be a proportionate decrease of OH- concentration to maintain the constant value of ionic product.

Salt affected soils can be defined as the soils containing excess amount soluble salts in their profiles in a proportion that adversely affect to soil properties and ultimately on crop growth. The soluble salts present in these soils are composed primarily with calcium, magnesium and sodium as cationic and chlorides sulfates and carbonates as anionic constituents along with the presence of potassium, nitrate and others as minor quantities. All soils invariably contain some soluble salts, but they cause harmful effects on crop growth only when accumulates in excess amount in soil solution or increase their concentration in exchange complex of the soil. Based on the presence of sodium salts and the predominance of sodium in the exchange complex, salt affected soils are classified into main categories of 1) Saline soils – contain excess soluble sodium in soil solution with little or no sodium content in exchange complex, 2) Alkaline (Sodic) soils – contain appreciable quantity of sodium adsorbed in exchange complex of soil but may or may not contain soluble sodium salts in soil solution. These soils are also divided into following types –

Soil survey is essentially a systematic examination of morphological, a set of other variable soil characteristics, description, classification and mapping of soil in an area alongwith a report making an interpretation to predict their potentials for various uses particularly for crop production.

Activities of Soil Survey Soil survey is composed of the following activities –

1. Anticipation of soil variability - The initial activity of soil survey is obtained by classifying the surveyed data according to different land forms and existing land uses either through field traversing, or aerial photo or by satellite images of the concerned area.

2. Characterisation and classification – This is done on the basis of soil profile description supported with soil analytical data.

3. Soil mapping - This is performed by showing the distribution of types of soil or soil mapping units based on already classified soils with their landforms, and land uses or their combinations.

4. Interpretation - It is the process of making prediction about the potentials of soils for various uses like choice of farm practices – agriculture, horticulture, forestry, pastures etc. and their management practices.

Classification means the process of ordering or grouping of objects having large number of population and wide variations into shorter one in a systematic manner with selected characteristics. Soils being the natural objects have no exception with other objects to classify them in a best possible way. Thus, soil classification refers to the systematic categorization of soils into various groups, classes or any simpler form based on the similar properties and other distinguishing characteristics. The main purposes of soil classification are to organize knowledge, easy remembering of the soil properties for each group and better understanding about the components and the relationships among individuals and various groups of soils. Various soil classification systems have been evolved during the past for categorizing the soils into various groups but the Soil Taxonomy has been now accepted as most scientific system of classification.

The solid phase of a soil system makes up a mixture of inorganic and organic materials. The inorganic fraction of soil originated from the weathering of rocks and minerals consists of rock fragments and minerals of varying sizes and composition. Hence, this inorganic soil fraction composed by soil minerals also referred as mineral fraction of soil and is caused due to alteration of mineralogical composition of soil by bioclimatic factors. A great deal of attention is being paid to the composition of minerals in soils, their formation and distribution over the earth’s surface. Soil genesis or pedogenosis (a more useful term as soil belongs to pedosphere) deals with the processes of formation and development of soil. The branch of soil science that integrates the studies of genesis, morphology and classification of soils as natural body is called Pedology. The process of weathering of rocks, pedogenesis and development of soil profile are described successively in this chapter.

Temperature is the measure of the thermal state of a body with respect to its ability to transfer heat. Soil derives its heat almost entirely directly from the sun and losses much of it back into the atmosphere. The major processes for heat transfer in soil are: Radiation, Convection, Conduction and Latent heat exchanges between soil and atmosphere. The most important source of which is the incident radiation supplying almost all the heat energy for the biosphere and also determines the thermal regime of soil. Soil temperature or thermal regimes of soil is an extremely important property of soil as it regulates plant growth directly and influences moisture and aeration status in soil, soil structures, microbial activities and decomposition of plant residues and the availability of plant nutrients . It is controlled mainly by its thermal properties and radiation exchange over the surface and their variations within the soil. The quantity of incident solar radiation and heating the soil depends on the several factors such as exposure and latitude, albedo, soil colour, slope vegetation and composition of soil.

Water is absolute necessary constituents for the survival and growth of all the living substances on earth. It is the most essential ingredients for many of the physiological and metabolic process in plants, like photosynthesis to form sugars, translocation of cell constituents and maintenance of cell turgidity. Soil, being an adsorbent of water received from precipitation or rainfall acts as reservoir to meet requirement by plant during growing season. Water retained in the soil serves as solvent to dissolve salts and nutrients and as a carrier to translocate them for absorption by plants. It plays significant role in weathering reaction, soil forming processes and profile development. Water is also important for growth and activities of microorganisms influencing decomposition of organic matter, transformation of mineral nutrients and other physical, chemical and biological properties in soil. This chapter deals with the retention and movement of water in soils to obtain better understanding of soil-water-plant-atmosphere relationships.

The major components of soil consisting with mineral and organic matter, water and air produces a three phase systems of solid, liquid and gas. Many of the soil properties influencing crop growth and other uses depend mostly on the relative proportions of these components as well as the size, shape and arrangements of the solid matters. The physical properties of soil have strong significance in sustaining agricultural productivity. Fertiliser alone or in conjunction with suitable crop varieties and plant protection measures cannot be sufficient towards improving crop productivity unless the soil physical properties are maintained at satisfactory level. Improvement and restoration of physical properties in soil are necessary for protection of soil resources against degradation. The physical properties of soil discussed in this chapter includes soil densities, texture, structure, porosity and consistency of soils and colour of the soil.

Soil Colloids A colloid, also known as colloidal solution or colloidal system, is a mixture in which finely divided particles (less than 1µm in size) known as dispersed phase are suspended in a medium, called dispersion medium. The particles must be dispersed in a medium and both the dispersed phase and dispersion medium may be solid, liquid or gaseous which leads to numbers of possible colloidal systems. In soil, the clay fraction (< 2µm in size) together with finer fractions of some organic matter forms the composition in a state of colloidal nature, known as soil colloids. The soil solids as dispersed phase predominates in the dispersion medium (soil solution). As such, colloids in a soil are referred to as ‘sol’. Clay colloids display the most reactive fractions of soil governing their distinct properties such as adsorption and exchange of ions, zeta potential, flocculation and other electrokinetic phenomenon.

The organic constituents of soils or soil organic matter is the most essential components of soil consisting of plant and animal residues at various stages of decomposition, cells and tissues of living or nonliving organisms and the substances synthesized by their decomposition. Soil organic matter exerts profound effect on soil productivity as it acts as source and sink of plant nutrients especially nitrogen and sulphur. It also involves in major biochemical processes to transform or release of plant nutrients into their available forms. Thus, it plays vital role in soil fertility maintenance, through increasing cation exchange capacity and improving soil physical properties, such as bulk density, aggregation, water retention capacity and also supports all kinds of biological activities in soil. The soil organic matter mostly concerns only with dead organic fractions formed from the decomposition of original plant and animal residues using as a source of food and energy by the soil microorganisms. It can be distinguished into –

Soil is a dynamic natural body of the uppermost layer of earth’s crust produced by the transformation of mineral and organic substances on the earth’ s surface under the influence of environmental factors over a long period. It is the most basic of all natural resources upon which all living forms on the terrestrial ecosystem directly and indirectly depends. However, soil resources are finite, nonrenewable, fragile and heterogeneous in space and time. As a component of pedosphere, it occurs as interface between the lithosphere and atmosphere and strongly interacts with biosphere and hydrosphere (Figure 1 & 2).

Soil is a natural resource that exists on the planet much before the existence of mankind on it. The human relationship with soil throughout the history of mankind has marked its ability of crop production and influenced the success of civilisation. Such relationships also affirm soil as the foundation of agriculture and food security, supplying all the essential ingredients to plants, as fundamentals to life on planet, and support various biogeochemical cycles on earth’ s terrestrial ecosystem. Prosperity of human society depends on the utilisation of planet’ s resources in creative and productive ways. Of these resources, soil has gained much importance as it provides human to sustain themselves with their capacity to food production, to make significant contribution towards biodiversity and other ecosystem services that are vital for the functioning and resilience of earth’ s environment. Soil occupies a pivotal position in the environment to maintain its quality.

Introduction Rapid increase in world population in last few decades has challenged the food producing sector (Agriculture, poultry, dairying and aquaculture) massively to meet the global food demand. The population is expected to be 9.9 billion by 2050 which means the food producing sector have to increase production by 60% further more than the current production (FAO, 2020). According to FAO (2016) approximately 17% animal protein and 7% total protein consumed by humans were provided by fish. Accordingly, per capita fish consumption was gradually increasing worldwide at 1.5% rate annually from 9.0 kg in 1961 to 20.5 kg in 2017 (FAO, 2018; Fajardo et al., 2022). Aquaculture which accounts for 47% of total fish production is expected to overtake capture fisheries by 2024 and reach 52% by 2029 (FAO, 2020).

Introduction “Xenobiotics” are “foreign compounds,” which are alien to the organism and removed from their natural environment. Xenobiotics are substances that are either alien to an organism or do not form a natural part of its diet. Compounds including pharmaceuticals, food additives, & environmental toxins are examples of xenobiotics. Normally, these substances are removed from the body by being broken down into compounds and then being expelled through the kidney, bile and lungs. For the pharmaceutical business, enzymes that metabolize xenobiotics are crucial because they are in charge of breaking down medicines. Similarly, xenobiotic transporters influence how long medications remain in the body.

Introduction Feed is a major source of nutrition in semi-intensive and intensive culture systems. Fish fed with formulated feed is used for their growth, maintenance, and reproduction. Feed Energy utilized for maintenance is mainly for health and survivability. In intensive aquaculture, animals almost exclusively depend on an external supply of high protein feed (generally >20%), usually based on fishmeal (Beveridge and Little, 2002) because of its high protein content, better bioavailability of amino acids, palatability, and unknown growth factors. Hence fish fed with a fish meal-based diet exhibits better growth performance, feed conversion, and fish health than fish fed with other animal and plant-based protein sources (Hardy and Tacon, 2002; Pike and Barlow, 2002; Tacon, 2003; Cook et al., 1996). Still, Global fish meal production is annually decreasing since 1994 due to increased human utilization and increased use of fish residues and by-products, increasingly replacing whole fish for fish meal (FAO, 2020). Hence many scientists were passionate about replacing the fish meal with an alternative feed ingredient without compromising growth.

Introduction The ecological stability and food web of intertidal environments are significantly influenced by macroalgae. The majority of marine organisms, including macroalgae, coral reefs, sponges, and the organisms that they are associated with, are well known for producing secondary metabolites and bioactive compounds, which increase their value in a variety of industries, including food, neutraceuticals, pharmaceuticals, and others. Among them, seaweeds play a vital role in promoting health by offering a variety of phytochemicals with antioxidant, antibacterial, anticancer, and antiviral action (Ngo et al. 2012). Worldwide, there have been more than 20,000 macroalgal species identified. In South Asian nations including China, Japan, and Korea, it has been used as sea vegetables. India now has 841 macroalgal species identified,including 434, 191, and 216 species of red algae, brown algae, and green algae, respectively (Oza and Zaidi, 2001).

Introduction Fish oil is the major source of essential Fatty acids (EFA) for humans. Generally, Fish requires three long-chain highly unsaturated Fatty acids (HUFA) for their normal growth and development including reproduction like docosahexaenoic acid (DHA, 22:6n-3), eicosapentaenoic acid (EPA, 20:5n-3) and arachidonic acid (ARA, 20:4n-6) (Sargent et al. 1993a, 1995, 1997). Like the terrestrial mammals, DHA, EPA, and ARA are all involved in maintaining the cell membrane structure and function of fish but majorly EPA and DHA are considered. Moreover, the EPA and DHA are the major currency as fatty acid for the synthesis of phospholipids, Prostaglandins, and energy etc. However, the biosynthesis of EFA in fish changes in accordance with the relative bioconversion capacity of the PUFA (Linoleic acid and α-Linolenic acid) as shown in figure 01.

Introduction A genome marker or a genetic marker is words commonly used to refer to a marker, which is identical to the term “marker.” Genes, genetic variants, or random sequences can all be represented by markers. Markers act as milestones or signposts while creating DNA and genomic maps. Markers are DNA sequences that are frequently identified by their position in a genome. The transmission of traits or the risk of sickness within families can be tracked using markers. It is essential to the continued existence of the species and boosts an organism’s ability to adjust environmental conditions. In conjunction with other evolutionary forces like genetic drift and selection, genetic diversity inside an individual evolves, leading to divergence at the population/ communities, species, as well as higher order taxonomic levels (Askari et al., 2013). Numerous fields, including evolutionary research, resources management and conservation, and genomic improvement programmes, can benefit from the conclusion derived from genetic variety data (Liu and Cordes, 2004).

Introduction Shrimp farming is a lucrative sector in the food production industry. According to SOFIA (2020), 9.4 million tonnes of crustaceans were produced in 2020 worldwide, with 4.96 million tonnes coming from Penaeus vannamei. India is one of the largest global producer and exporter of farmed shrimp. In India, shrimp production increased significantly after introducing Pacific white leg shrimp, Penaeus vannamei, in 2009. Among the cultured shrimp species, Penaeus vannamei is the leading species under culture in India, with an estimated production of 7.12 lakh tonnes (MPEDA, 2020). Intensification of culture and diversification of species provoke the incidence of diseases making diseases the major constraint in aquaculture, leading to tremendous losses. Shrimp diseases are of viral, bacterial, fungal and parasitic origin.

Introduction Organ-On-a-Chip (OOC) is a developing trans-disciplinary technique that shares similarities with tissue engineering and lab-on-a-chip technologies. It has benefited from recent advancements in microtechnology (particularly microfluidics), cell biology, physiology, and tissue engineering and is motivated by the need for reliable, low-cost in vitro drug screening models. It can be characterized as a microfluidic-based perfusion device that facilitates an invitro cell (co-)culture and tries to reproduce certain structure(s), function(s), and important elements of human or animal metabolism of a particular tissue or organ in healthy and pathological physiology. Important features of live organs are such as extracellular microenvironments, spatiotemporal cell-cell interactions, and physiologically important tissue microarchitecture.

Introduction NGOs (Non-Governmental Organizations) are organisations with professional staff that work to lessen human suffering and advance developing nations. The number of Non-Governmental Organizations (NGOs) in India is close to 3.4 million, and they work in a range of sectors, from disaster relief to advocacy for underserved and neglected groups. It is a nonprofit organisation that operates without interference from any governmental body. It is taskoriented and organised by people with common interests in a local, national, or international setting. It performs a variety of services and charitable tasks. Particularly, some are structured around particular concerns, such as health, the environment, or human rights. These make up a sizeable portion of civil society and bring about quick social change. They have developed into a vital and vocal platform for civil society participation in public affairs (Desai, 2014.).

Introduction Fishermen of Gulf of Mannar coast were largely depending on traditional fishing gears, and they were mainly exploiting the coastal fishery resources before 1960’s. After the introduction of trawl gears and mechanized fishing boats during 1960’s fishermen were more comfortable with plenty of fish catch, especially the high-valued demersal shrimps. The fishing effort was also increased at a tremendous pace in this region with the addition of stern trawlers. Due to this increment in the fishing effort, the fishery resources and their life-supporting systems such as coral reefs and sea grass beds are seriouslydisturbed.

Introduction Hokersar wetland (34°06’ N latitude, 74°05’ E longitude), a Ramsar site and a protected wildlife reserve is located in the northwest Himalayan bio geographic province of Kashmir, back of the snow-draped Pir Panchal. The wetland shelters about two million migratory water-fowl during winter that migrate from Siberia and the Central Asian region. The wetland is fed by two inlet streams Doodhganga (from east) and Sukhnag Nalla (from west). It is the only site in Kashmir with remaining reed beds and serves as a migration route for specifically 68 waterfowl species from Siberia, China, Central Asia,and Northern Europe, including the Large Egret, Great Crested Grebe, Little Cormorant, Common Shelduck, Tufted Duck, and endangered White-eyed Pochard (Ramsar, 2021).

Introduction Technology is the application of knowledge and/or equipment in undertaking and accomplishing certain activity. Fisheries technology is a systematically organized knowledge and materials applicable to production problems to help to boost the present level of fish productivity and or extend the existing range of production. Fisheries technologies are wide range of importance; Technological innovation in aquaculture is leading an evolution in aquaculture practices, thereby reducing losses and increasing efficiency. Technology in aquaculture affects many areas of fishery, such as seed production, feed production and management, pest and diseases management, production, harvesting, marketing, processing, etc. Induced breeding technology in Indian Major Carps transformed the growth of aquaculture sector from traditional to intensive aquaculture practices and led to success of modern aquaculture industry. Mechanization in fishing increased the harvest with less time and minimal human drudgery. Fish processing technologies improved product shelf-life, reduced fish loss and added value to the products.

Climate Change - An overview The most studied topic in recent years was climate change, due to its increasing importance. Climate change refers to long-term shifts in temperatures and weather patterns. These shifts may be natural, such as through variations in the solar cycle or due to anthropogenic activities, since the 1800s, human activities have been the main driver of climate change, primarily due to burning fossil fuels like coal, oil and gas. The process of raising the earth’s temperature is known as global warming. Climate change is one result of global warming in different places on the planet. Many people think that climate change means only global warming or an increase in temperatures. But the rise in the temperature is only the beginning of the story. Because in the Earth system everything is connected to one another, changes in one area or in one aspect of the system can influence changes in other areas. The consequences of climate change include flooding, intense droughts, water scarcity, wildfires, rising sea levels, melting polar ice, catastrophic storms and declining biodiversity. Adapting to climate change consequences protects people, businesses, livelihoods, infrastructure and natural ecosystems. It covers current impacts and those likely in the future.

Introduction The increase in population has led to the demand for good quality food. Consumer food demand is a key factor in the development of many agricultural and food policy and high-quality food products with longer shelf lives is increasing all the time. Over recent years, Packaging has revolutionised the marketing and delivery of food goods, especially fishery products. The introduction of modern packaging technology and innovative packaging material processes paved the way for convenience products. In 2018, the value of fish and fish products exported was USD 164 billion because of improved chilling, packaging, and transportation technology has resulted in increased commerce in live, fresh, and chilled fish, which accounted for around 10% of global fish trade and 78% of the total amount shipped was for human consumption (Sofia 2020). When both fish and terrestrial meat exports for human consumption are considered, fish exports have been larger in value terms since 2016. (51% versus 49%). Furthermore, increased utilisation of fisheries and aquaculture products minimises loss and waste, which can assist reduce strain on fisheries resources and support sector sustainability.

Introduction PCR is an important molecular tool used widely in different applied research fields such as Infectious disease diagnosis, clinical medicine development and gene cloning etc., (Fang et al., 2008). Among different amplification methods, PCR was the first to be developed and has been the method of choice for its simplicity, easier methodology, extensively validated standard operating procedure and availability of reagents and equipment’s. However, it also has a good number of limitations such as advanced equipment, high cost, sensitivity to certain classes of contaminants and inhibitors requirement of thermal cycling etc. (Fakruddin, 2011). These limitations of PCR allowed to develop the alternative methods such as loop mediated isothermal amplification (LAMP) (Notomi et al., 2000), nucleic acid sequence-based amplification (NASBA) (Compton, 1991), self?sustained sequence replication (3SR) (Guatelli et al., 1990), rolling circle amplification (RCA) (Lizardi et al., 1998) etc., most of these techniques are isothermal that don’t require thermal cycler. These methods have many advantages over PCR in terms of speed, cost, scale or portability.

Introduction Surimi and surimi based seafoods are traditional products of Japan and occupy an important position in the dietary culture of the country. Today, the largest producers of surimi are the United States, Japan and Thailand. Surimi is also manufactured in China, Vietnam and Malaysia. The process of makingsurimi originated in Southeast Asia and was further developed in Japan in the 16th century. Surimi is a product of Japanese origin, derived from a traditional Japanese way of using and preserving fresh fish. The word ‘surimi’ comes from the Japanese words ‘suru’ meaning ‘to process’ and ‘mash/mi’ meaning ‘meat’. Technically, surimi is the stabilized myofibrillar protein which is obtained by mechanically deboned fish flesh, which is washed, mixed with cryoprotectants, and stored frozen. Washing not only removes fat and undesirable matters such as blood, pigments and odoriferous substances but also increases the concentration of myofibrillar protein. A fish-based product serving the raw material for preparation of analog of seafoods like crab, lobster, scallop & other shellfish.

Introduction Salmonella is a gram-negative, rod shaped bacteria, facultative anaerobe and non-spore forming. Motile by peritrichous flagella, except S. Gallinarum & S. Pullorum. Salmonella is a genus consists two species called S. enterica and S. bongori and six subspecies viz., enterica I, salamae II, arizonae IIIa, diarizonae IIIb, houtenae IV, indica VI and bongori V. the sub species were categorized into serotypes based on serological characters like somatic (O) - lipopolysaccharides (LPS) on the external surface of the bacterial outer membrane, flagellin (H) – globular protein peritrichous flagella and capsular (Vi) – polysaccharide - O acetylated α 1-4, linked N- acetyl galactosaminuronic acids occurs only in S. Typhi, S. Paratyphi and S. Dublin. Salmonella plays an important role in affecting the safety of foods as it survives in a wider range of environmental conditions (Finn et al., 2013). Seafood are often contaminated with Salmonella (Duran and Marshall, 2005) and their presence causes negative impact on seafood export. During 2020-21, India exported 1.15 MMT of seafood worth US$ 5.96 billion mainly to the USA, China and EU, which are the major importers of Indian seafood (MPEDA, 2022).

Background The Gulf of Mannar is one of the world’s richest marine biodiversity areas, as well as the first biosphere reserve in the region. The EEZ (Exclusive Economic Zone) of this region is around 15,000 square kilometres, with commercial fishing taking place in about 5,500 square kilometres (Arnold John M. 2017). Throughout the year, both mechanised trawlers and non-mechanized vessels fish in this area (Arnold John M 2001). Crustaceans are the most key members of the benthic organism strata and have a higher nutritional value for humans, and a large number of tiny species contribute to the complexity and sustainability of tropical ecosystems. (Hendrickx 1995). The Brachyuran crab is one of them, and it dominates many estuary regions where salinity and temperatures can vary substantially on a daily basis. (Ng et al. 2008). There are around seven hundred genera and five thousand to ten thousand species of brachyuran crabs in the globe.

Background The Enormous diversity of our planet harbors individuals of the sexually reproducing population that are unique and non-identical in nature. This unique nature is the source of this vast diversity. Taxonomy is critical for identification and classification. The oldest of the scientific disciplines, taxonomy, isdescribed as the theory and practice of classifying organisms (Mayr, 1982; Mayr and Ashlock, 1991). Taxonomy is a branch of systematics that deals with the idea and practice of classifying and describing diversity (Nelson, 2006). According to the global estimates of species (Mora et al., 2011; Costello et al., 2013), 1.2-1.5 million species are considered to be described and valid to date (Costello et al., 2013; Mora et al., 2011; Zhang et al., 2011). The enormous and intriguing variation among the species, as well as anatomical differences between species, developmental stages, and geographical ranges, make identification difficult. Rapid documenting of biodiversity should be a top priority before it is lost. This necessitates quick and accurate taxonomic expertise as well as enhanced identification methods, paving the way for the emergence of Integrative taxonomy (Dayrat, 2005), which combines all available data, whether morphological, behavioral, ecological, or molecular.

Introduction The Chilika lagoon situated in the eastern coast of India within 85º05' and 85º38' east longitude and 19º54' North latitude near Bay of Bengal and one of the biggest estuarine-style brackish water lagoon in Asia and the greatest migratory waterfowl wintering area on the Indian subcontinent (Suresh et al., 2018). In the monsoon & summer time, the lagoon's size varies between 1165 and 906 sq. km. The total catchment area of the lagoon is 4,406 sq km, of which 32% is made up of the Mahanadi delta and 68% is western catchment (Bengtsson et al., 2012). The lake has a distinctive combination of freshwater, brackish, and marine ecosystems with estuary characteristics. In 1981, Chilika Lake was chosen as the India's first "Ramsar site" and it considered as one of the biodiversity hotspots of the nation (Kumar et al., 2012). The lake is very productive and has abundant fisheries resources. Over 0.15 million fishermen live around the lagoon and rely on its productive fishing grounds for their livelihood (Suresh et al., 2018). The lake area is home to certain uncommon, endangered and IUCN threatened species.

Introduction The fish is an important source of protein as it constitute about 17 of the total animal protein (SOFIA, 2018) and the rising demand for fish has led to unsustainable exploitation of marine and inland water resources and fishstocks are getting overexploited, due to which the output from capture fisheries is uncertain. This has put difficulty for the management of our open water resources. It is now urgent to develop a management strategy for conservation of natural resources for future generation as our responsibility. Hilborn and Walters (1992) define stocks are arbitrary groups of fish large enough to be essentially self-reproducing, with members of each group having similar life history characteristics. Stock is defined as "a part of a fish population usually with a particular migration pattern, specific spawning grounds, and subject to a distinct fishery" by the International Council for the Exploration of the Seas. Understanding the importance of delineating the stocks and their boundaries which have become an essential part of fishery management and conservation.

Intoduction Cybertaxonomy is an abbreviation for "cyber-enabled taxonomy." It shares the traditional goals of taxonomy: to explore, discover, characterize, name, and classify species; to study their phylogenetic relationships; and to map their ecological associations and geographic distributions. To improve the speed with which we can help in providing taxonomic products and information, there is undoubtedly a requirement to move taxonomic endeavour into the digital era. Currently, the rate at which we record and maintain morphological information that enables species discovery is the primary constraint on taxonomic productivity (Lasalle, et al., 2009). Cybertaxonomy is one attempt to accomplish this complex goal. Cybertaxonomy employs a collection of electronic tools to assist and equip the science of taxonomy in accelerating species invention and the implementation of taxonomic expertise in biodiversity investigation.Cybertaxomy can yield results more quickly and efficiently than ever before thanks to adoption of digital technologies and cybertaxonomy.

Introduction A few decades back, no one would ever consider the potential danger posed by an ocean overrun with jellyfish? But many researchers around the world assure us that we can turn that danger into an asset with the help of scientific ideas and careful management. Gelatinous zooplankton like jellyfish are thought to have existed millions of years before the dinosaurs did. There are cases where these emotionless, mindless, bloodless organisms kill an adult human (Wilson, 1947). Despite being an annoyance, they could greatly benefit human society in many ways. The unfortunate truth is that even though they have 500 million years of history, they still appear to be an untapped opportunity. Jellyfish are not only edible, but also extremely nutritious due to their low calorie, fat, and protein/collagen content. Jellyfish are known for their refined taste, which can lean toward the salty side. The texture is more of a factor; it's not as gelatinous as one might think, falling somewhere between a summer squash and a glass noodle. According to the Intergovernmental Panel on Climate Change (IPCC) report published in 2019, human activities have had an impact on virtually all marine organisms, including corals, oysters, and other marine organisms. However, jellyfish are more resistant to the acidic effects of the world's oceans. This does not necessarily imply that these organisms are highly immune, but they are doing better than average. There are about hundred known venomous jellyfish species out of an estimated 10,000 worldwide.

Introduction The impact of COVID-19 on the fisheries and food industries of vary, and the situation is rapidly evolving. Fisheries products that are highly dependent on international trade suffered quite early in the development of the pandemic from the restrictions and closures of global markets, whereas fresh fish and shellfish supply chains were severely impacted by the closure of the food service sectors (e.g. hotels, restaurants and catering facilities, including school and work canteens). Although COVID-19 does not fish, the fisheries sector is still have indirect impact in the pandemic caused changing consumer demands, market access or logistical problems related to transportation and border restrictions (Purkait et al., 2020). This will in turn have a damaging the effect on fisheries and aquaculture farmers in livelihoods, as well as on their food security of the populations that rely heavily of the fish for protein and essential micronutrients. The processing sector also faced closures due to reduced/lost consumer demand. This has had a significant impact, especially on women, who form the majority of the workforce in the post-harvest sector (Avtar et al., 2021).

Introduction According to the United Nations Department of Economic and Social Affairs, the world population increase from 7.7 to 9.7 billion by 2050; therefore, a growing demand for seafood and the production gap is anticipated due to stagnating fish supply from capture fisheries. The production gap may be curtailed by intensification of aquaculture practices rather than horizontal expansion. Intensive farming practices such as cage and pen culture in open water have gained significant attention and are related to the efficient utilization of untapped potential water bodies and of existing resources.

Aquaculture production is promptly increasing all over the world. To increase the demand and for best management practices, we required additional technological innovations in various fisheries and aquaculture fields such as breeding, feeds, disease management, etc. The study of epigenetics provides a new way to comprehend ecofriendly-induced epigenetic markers linked to economically relevant features, disease resistance, and other qualities, allowing for the establishment of more suitable breeding conditions in aquaculture. CH Waddington invented the term “epigenetics” in 1942 to define the “study of the interactions between genes and their products that bring the phenotype into being,” which establishes the relationship between DNA segment and phenotype (Waddingto, 1942). Epigenetics is defined as processes or events that influence gene activity inheritance without relying on variations in DNA base sequences.

1. Introduction The chapter aims to bring out the potential benefits of radiation processing technology for value-addition of millets. How the radiation processing technology can be exploited for making millets as a popular staple food would be the central theme. The key focus is to establish if irradiation (the term generally used for radiation processing of any material) can be employed for making millets for different purposes relevant to farmers and consumers. In order to understand and prove, we would list out the challenges involved in developing the market for millets. The key points that need to be considered for this go-to-market strategy for millets are : a) Millet grains have a long shelf-life, much better than the popular grains e.g., rice and wheat, consumed worldwide, but millet flour shelf life is significantly much shorter.

1. Introduction According to the United Nations Food and Agriculture Organization, 780 million of the estimated 792.5 million malnourished people globally are in countries that are developing. Despite expanded agricultural production, “hidden hunger,” which is often caused by a shortage of vital micronutrients in daily meals, affects around 2 billion people worldwide. Majority of the population is relying on plant-based diets which are critical for sustaining nutritional security and are the primary source of nutrients required for optimal growth and development. Most of these diets are found deficit in major nutrients such as proteins, iron, calcium and Vitamin B12.However, a considerable number of Asian and African populations suffer from nutritional inadequacies as a result of consuming plant-based diets (Tripathi et al., 2019). Earlier, the main concern of farming systems was crop productivity and yield. However, there has been a shift in emphasis toward human health and well-being.

1. Introduction Ayurvedic texts like Charak Samhita and Sushruta Samhita, have described millets as the staple food useful in managing diabetes mellitus (Sachan Kumar, 2004). Based on the experience of eating these millets for time immemorial, there exists also a strong traditional knowledge about health benefits associated with them. For example, as per an adage in the state of Karnataka, India: “Those who eat rice will grow as a light weight; their body being just like that of a bird; those who eat Jowar will become as strong as a wolf but those who eat Ragi (millets) will be the strongest of them all, plus they would be free from illness (‘nirogi’ in Sanskrit)”! Certain studies from literature refer nutraceutical character of millets, especially, Kodo and Kutki, which in our opinion should help mankind in eradicating malnutrition and hunger while ensuring sustainable supply of food.

Millets have immense potential of providing nutritional security worldwide and play a pivotal role in food and nutrition economy. The nutritional aspects of millets are comparatively superior from the widely consumed cereals across the globe. With the presence of various essential macro nutrients millets are also enriched with the goodness of micro nutrients as minerals, vitamins and possess various bioactive compounds that portray several health benefits. The nutritional attributes of the millets are accompanied with several antinutritional factors such as tannins, phytates, saponins, trypsin and amylase inhibitors etc. that limit the bioavailability of the essential nutrients and minerals in these wonder grains upon consumption.

. Introduction Millets, once considered as humble and forgotten grains, have made a remarkable comeback owing to their numerous health benefits, sustainability, and resilience in diverse agroclimatic conditions. Millet consumption is gaining momentum globally and thus it becomes imperative to establish clear and comprehensive standards for these grains. The chapter gives an insight into the reasons why millet standards are necessary, the challenges associated with implementing such standards and advocacy for a concerted effort to promote these nutritious grains as staples in our diets.

1. Introduction Fonio (Digitaria exilis), also known as acha, hungry millets, and fundi in various regions, is a minor and underutilized millet with exceptionally small size (H. Sartelet et al., 1996; Bello et al., 2020). This ancient crop native to West Africa is considered one of the oldest cultivated millets for ensuring food security. Figure 1 illustrates the components and structure of fonio millets. In recent times, fonio millet has garnered increased attention due to its remarkable nutritional and functional properties (Zhu, 2020). Being gluten-free, it is rich in nutrients such as carbohydrates, fat, fiber, vitamins, and minerals (Fe, Cl, K, Mg) as well as essential sulphur-containing amino acids like methionine and cysteine, which also possess phenolic properties (Barikmo et al., 2004; Zhu, 2020).

1. Introduction Plants have played a crucial role in fulfilling human needs for centuries, and among the vast array of plant species, Job’s Tear (Coixlacryma-jobi L), also known as adlay, coix, and Chinese pearl barley, holds significant potential as a crop in the Poaceae family. There are four main varieties of Job’s Tear, including C. lacryma-jobi var. ma-yuen, C. lacryma-jobi var. Puellarum, C. lacryma-jobi var. lacryma-jobi, and C. lacryma-jobi var. Stenocarpa. The Indo-Maynmar region serves as the primary producing area for Job’s Tear millet, with other significant production countries being China, Japan, the Philippines, Myanmar, Thailand, Sri Lanka, and India (Laxmisha et al.,2022). The versatile crop has earned the status of a staple in many regions, not only ensuring food security but also improving the livelihoods of rural farmers. Beyond its nutritional significance, Job’s Tear has garnered recognition for its potential health benefits.

Browntop millet (Urochloaramosa) is a warm-season crop that produces seeds that are heavier than other millet varieties. This crop is cultivated in several types of soils and climates. Browntop millet is an introduced grass that originated in Southeast Asia. It is grown in Africa, western Asia, Arabia, China, and Australia. It was introduced to the United States from India in 1915. It is also useful for controlling erosion, producing hay, feeding wild animals, and producing grain for human use. In addition, it is also utilized as a crop for wild animal food. In dry and semi-arid regions, millets constitute the main food supply. Although India is the main producer of millet, output and use have fallen. Browntop millets are nutrient-dense. Browntop millet is a miracle crop for arid and rainfed areas. Nearly all of the necessary nutrients are found in browntop millets.

1. Introduction Millets are the oldest crops known to mankind. They are mostly cultivated for human consumption however; some are also used as animal fodder. Barnyard millet Echinochloa frumentacea is a multi-purpose crop belonging to the kingdom plantae, order-poales, family-poaceae, subfamily-panicoideae, genus-Echinochloa & species-E. frumentacea. It was domesticated about 4,000 years ago with two main species: Echinochloa esculenta (Japanese barnyard millet) and Echinochloa frumentacea (Indian barnyard millet). The former species is mainly grown in Japan, Korea, and northeastern China, while the latter is grown in Pakistan, India, and Nepal. In India, barnyard millet is grown in the Himalayan region from the north to the Deccan plateau in the south and is popularly known as jhangora or sawan millet.