eBook Chapters

Gladiolus is a fluoride pollution indicator plant, as it expresses the effects of fluorine at very low levels. Symptoms of scorching of the leaves look like drying of the tips of the leaves. A strong application of super phosphate is also associated with fluoride toxicity. By spraying 5 percent lime or Magnesium sulphate, it decreases

In grape growing areas in many parts of the world this illness is a very popular disorder. In this disorder, a bold beer is surrounded by shoot berries, and the name of the hen and of the chicken disorder is like a hen, as bold berry and chicken. The fruit has a sour taste. The signs are the death of rising tips, falling leaves and the fragility of new shoots. With the development of interveinal chlorosis between the edges, the leaves may be deformed, and this is particularly evident after fruiting.

Bronzing is a complex nutritional condition in guava (Psidium guajava L.). It manifests in the interveinal tissue of older leaves as bronze or copper colour development, while terminal leaves remain green. This is attributable to the inadequacy of elements P, K and Zn. Bad management and low soil fertility coupled with soil acidity are often due to it.

Physiological disorders are abnormalities in plants which are associated to non-pathogenic factors. A plant or its parts may show unusual growth, function or deformity. Such abnormalities are widely referred to as disorders. These may be incited by nutrients deficiency or excess, hormonal imbalance, abnormal growing conditions etc. Some commonly observed disorders have been dealt in here suitably.

Tip-burn is the marginal collapse and necrosis of rapidly spreading inner lettuce leaves, at or near the leaf margins. Typically, the condition occurs near harvest, when it may lead to complete crop failure. Early signs include discoloration of the veins and/or the growth of dark brown to black spots near or at the margins of the leaves. The necrotic areas coalesce as the disease progresses, creating a lesion up to several centimeters long.

Problems are low fruiting / non fruiting / irregular fruiting in the country’s litchi farming area. The potential of bear litchi has been identified as variety, although some of the bearing terminals in the present year will be more active in the next year (70-95 percent).

This is one of the most serious difficulties in mango farming since it makes mango agriculture less rewarding for farmers. In one year (a year) and very little or no harvest next year, mango trees appear to bear huge crops (off year). This bieniality is therefore also present in normal ranges (Singh, 1990). 

When the soil temperature stays at or below 20 0 C, seeds germinate poorly. During early spring-summer planting, this issue of seed germination occurs when seeds are to be sown at low temperature conditions.

Twitching is a condition occurring predominantly on the surface of the fruit which is exposed to direct sunlight; however, it is not well understood what the source of the disease is. Growth in immature fruits cannot be detected during later stages of fruit maturity. On cv. Golden Solo Party there are a few examples. This is termed the “frog skin” or “fox skin.” It shows on the fruit’s surface as the Dark Brown Flecks. 

Ordinarily, fruit bears a single crown, but fruit bears more than one in some cases. The top of the fruit will therefore be smooth and wide and the fruit will not be ideal for canning. These fruits have an insipid taste and are corky. It is intended to be an inherited character, often found in the Cayenne group to which the Kew variety belongs.

Pineapple, are well adapted crops for the farmers towards water economy due to its morphological, anatomical, and physiological characteristics. However, the plant contains rosette leaf structure can able to channels the light rainfalls and dew through stem and finally into the soil. It also have the ability to absorb water and nutrients through their waxy leaves and aerial roots and can capable to store water in specialized aquiferous leaf tissue; multicellular trichomes that cover the leaves and protect the plant from excessive transpiration by reflecting radiation; a thick cuticle covering the leaf epidermis that restricts water loss by evaporation, location of the stomata in furrows at the lower leaf surface where they also are covered by trichomes, limiting evapotranspiration; and its nocturnal carbon dioxide fixation via the crassulacean acid metabolism (CAM) carbon assimilation pathway, which results in stomatal opening primarily at night when evaporative demand is lowest (Reinhardt et al., 2018). The most common propagating material of pineapple is suckers or slips. Suckers are used to arise from the underground parts of the plant are used for propagation. Slips arise from the fruiting stem and the crown region on top of the fruit.

In this context, it is important to know the nutritional aspects of pineapples which are as attractive as their unique anatomy. “Pineapples contain high amounts of vitamin C and manganese,” said San Diego-based nutritionist Laura Flores. These tropical fruits are also important for the dietary fiber and bromelain (an enzyme). “As well as having high amounts of manganese, which is important for antioxidant defenses, pineapples also contain high amounts of thiamin, A, B vitamin that is involved in energy production,” Flores said. Pineapples are fat-free, cholesterol-free and low in sodium (Arpaia et al., 2004; De Costa, 2010). Side by side they contain sugars of about 14 grams per cup (www.livescience.com, 2019). In continuation with this, the chapter was focused on physiological disorder of pineapple caused by various reasons.

Basically, non-pathological conditions are the reasons of physiological disorders of any kind of crop plants; it includes poor light, adverse weather, water-logging, phytotoxic compounds or a lack of nutrients, which affects the normal functioning of the plant system. Sometimes physiological disorders may be initiated before harvest, continue their development after harvest, or appear after harvest. In was observed several times that physiological disorders are causative agent for the deterioration of horticultural commodities which leads to economic losses. An important commercialized fruit i.e., pineapple is also facing the same problem of different kind of physiological disorders; it includes multiple crowns, fruit and crown fasciation, collar of slips, dry fruit and bottle neck, sun-scald/ sunburn, blackheart etc.

Fruit cracking is a serious problem of pomegranate (Punica granatum L.) particularly in arid climate. Cracked fruits are sweet but unfit for long distance transportation. Incidence of cracked fruits varies from 10 to 70 % depending upon the prevailing environmental conditions. Longitudinal or radial splitting of rind surface occurs.

There is secondary elongating growth in the roots that gives a form of fork like structure to the root. This occurs in heavy soil due to soil compactness. An elongated radish root is encouraged by un-decomposed organic manure. It can be fixed by decreasing field moisture, balanced irrigation and also by sowing radish and carrot in sandy loam or light soil with loose and friable soil in nature.

The normal blooming stem on the greenhouse rose has fully developed sepals, petals and reproductive organs. The inability to build a bloom at the apical end of the stem is a typical phenomenon which in such shoots is termed blind. There are sepals and petals; however, they are not complete or aborted in the reproductive portions.

Blossom end rot is a very common problem on green and ripe tomatoes. It started with light tan, water-soaked lesion, and then increased to black and tough. Although blossom blight itself caused only local damage, secondary biological invasions frequently lesions caused fruit rot complete.

Symptoms of pale or yellow-green leaves (chlorosis) first occur in the older leaves. At the leaf margins reaching toward the midrib or central vein, reddish tints gradually emerge. The leaves are thin. Growth overall is markedly reduced. Deficiency results in rhizome yield loss.

In addition to pathogenic diseases, numerous abiotic disorders may also arise during growth, development and post-harvest storage of solanaceous vegetables. The physiological disorders of vegetables that have been included in this chapter are directly or indirectly associated with genetic, cultural, nutritional, physiological and environmental factors, and in most of the cases, the definite cause of disorder is not well understood due to the association of numerous factors together. These disorders may be related to colour, shape and form/condition of the produce. The genesis of physiological maladies was earlier poorly understand due to complexity in their characteristic symptoms but at present is relatively more transparent. The characteristic symptoms of abiotic disorders discussed below have not been attributed solely to a single agent or to a single cultural or environmental factor. The environmental factors correlated with the incidence of these disorders include high light intensities and low or high temperature of that growing area. For many abiotic disorders, very limited research work has been done, and the causes are poorly understood both in terms of why cultivars differ in susceptibility and why certain environmental factors predispose the plants or parts of the plant to the disorder. The growers feel concerned with the incidence of abiotic disorders as these cause huge economic loss. Therefore, the control of these abiotic disorders is essential for profitable production of solanaceous vegetable crops. In this chapter, emphasis has been given on practical aspects of diagnosis and potential control measures.

DEFINITION

Plant disease in which no pathogens or parasites is associated with the cause is known as Non-parasitic disease. They are also called as non-infectious or physiological disorders. When no pathogen is found, cultured from or transmitted from a diseased plant, then the disease is said to be caused by a non-living or environmental factor. These diseases occur because of disturbances in the plant system by the improper environmental conditions in the air or soil or by mechanical influences.

Introduction

The physiological disorder of a mineral nutrient is entirely contingent upon its function within the plant body. Inadequate or excessive supply of any essential element can result in metabolic disruptions, influencing the activities of enzymes, rates of metabolic reactions, and concentrations of metabolites. Alongside alterations in metabolic patterns, severe deficiencies of specific essential elements also give rise to distinctive effects in leaves, stems, roots, blossoms, and fruits.

A. Nitrogen

Functions: Nitrogen is essential for plants, playing crucial roles in protein synthesis, nucleic acid formation, and chlorophyll synthesis. It is a key component of enzymes, contributing to various metabolic processes. Nitrogen also supports root development, cell structure, and the synthesis of secondary metabolites. Striking a balance in nitrogen levels is vital for maintaining plant health and ensuring optimal growth and productivity. Effective nitrogen management is essential for sustainable agriculture and overall ecosystem well-being.

Harvesting is one of the agronomic management practices that require technical knowledge on maturation of the crops. This knowledge is much important in seed production than in commercial production.

Physiological maturation

• It is the stage of accumulation of maximum dry matter within the seeds. The moisture content of the seed at this stage will be in decreasing order (25-30%) and is expressed with maximum dry weigh of seed, germination and vigour potential. The physiological maturation is represented for individual seed and this maturation will not be the same for the population, due to differential flowering habit.
• The attainment of physiological maturation is represented by sigmoid curve of growth pattern. The physiological maturation can be represented both as duration and visible symptoms.

Introduction

In the past few decades, persistent change in climatic variables coupled with global warming lead to the genesis of climatic stress. Currently climatic stress is considered as the most serious ultimatum to livestock’s growth, development, production and reproduction in tropics and subtropics including India. Livestock’s in tropical countries are most commonly affected by the menace of climatic stress. It has been shown that, climatic stress upsets animal’s body homeostasis resulting in grievous decline in livestock’s production and productivity across the world. In general, livestock adapt to the climatic insults via behavioural, physiological, biochemical, metabolic, endocrine and molecular responses. Despite of these thermal adaptation mechanisms, livestock’s witnesses the perils of climatic stress thereby incur major loss in their production and productivity. Therefore, in this changing climatic scenario, it is imperative to rigorously understand and explore the precise mechanism of thermal adaptation to generate climate resilient species which could upsurge the socio-economic status of the farmers as well as the country.

Stress is force per unit area. When matter is subjected to stress; it may undergo changes in size, shape and displacement. Plants are grown in open environment and are likely to experience stress due to environmental conditions or when subjected to pests and diseases. The stress experienced by plants due to environmental conditions is called abiotic stresses. These include stresses caused by weather factors and climatic conditions and include moisture stress and thermal stress. The plants may also experience stress due to strong winds, dryness and as well as humid conditions (Fig.8.1).
The plants are generally classified into three types depending upon the ability to cope up with moisture stress as exhibited by-
• Drought resistance
• Drought tolerance
• Drought adaptations
The moisture stress may be to shortage of Water Compared to its requirements for evapotranspiration and metabolic activities. The plants may also suffer moisture

Introduction: N metabolism

Nitrogen is one of the three essential macronutrients for plant growth and yield (Su et al., 2005) and most crucial elements for root growth also (Fageria, 2014). Most macromolecules and a variety of secondary and signalling substances, such as proteins, nucleic acids, cell wall components, hormones, and vitamins, contain nitrogen (N), an important element. In order to assimilate nitrogen, nitrate must be reduced to ammonium, and then ammonium must be converted into amino acids. Perez et al. (1973) pointed out that the rice genotype with high protein yield translocated N from leaf blade to the developing grains more efficiently than the low protein genotype. This was reported due to a high concentration of free amino acids in the sap translocated to the developing grains rather than to differences in translocation rates. Therefore, proper understanding of N metabolism and amino acid translocation are prerequisite to comprehend higher grain protein in high yielding rice genotypes. Use of N by plants involves several steps including uptake, assimilation, translocation and remobilization; and recycling and remobilization when the plant is ageing (Fig. 1). The enzyme nitrate reductase (NR) assimilates nitrate, the main form of nitrogen available to agricultural plants in the field. This enzyme and the nitrogen status of various higher plant systems have a strong positive link, and growth, yield, or protein content can occasionally be connected to this enzyme’s level in seeds or leaves. Nitrate intake occurs at the root level, and it has been demonstrated that plants have two nitrate transport systems that work together to cohabit, absorb, and distribute nitrate from the soil solution throughout the entire plant. (Srivastava 1980) Following NO3- uptake by NO3- transporters and reduction of NO3- to NO2- by nitrate reductase (NR) in the cytoplasm, the process of NO3- assimilation commences (Lea and Miflin, 1974).

Introduction

The life cycle of a plant passes through biotic and abiotic stresses and plants are being attacked at different stages of growth by a number of disease causing organisms. These organism including bacteria, fungi, viruses, and nematodes attacks plants. These pathogens caused large crop losses and probably since the beginning of agriculture have contributed to human hunger and malnutrition. The control of plant diseases is thus of fundamental importance and is a major objective of plant breeding and pathology programme and agriculture chemical industry. Plants resists pathogens attack both with preformed defenses such as antimicrobial secondary compounds and by inducing defense responses (Hammond and Jones, 2000, Heath, 2000). Inducible defenses can be activated upon recognition of general elicitor such as bacterial flagellin and even host cell fragments released by pathogens damage (Gomez and Boller, 2000, Hammond and Jones, 2000). However, plants also involved sophisticated recognition systems to detect proteins produced during infection by specific races of pathogens (Martin et al., 2003).

Fruit ripening is a phenomena during which horticulture produce undergoes a series of complex physical and biochemical changes initiated through a series of hormones (Ethylene, auxin, abscisic acid (ABA), gibberellins, jasmonic acid, etc.) to attain maximum physiological maturity and favourable organoleptic properties. These changes lead to alterations in colour, texture, aroma, flavour and nutrient composition. In a nut shell, ripening involves increase in pulp to peel ratio, solubilisation of pectic substances, degradation of complex carbohydrates, organic acids and chlorophyll, accumulation sugars, flavour volatiles, polyphenolic compounds and pigments (carotenoids, xanthophylls and anthocynanins). The extent of these changes guide harvesting, readiness for processing and consumption decisions, with physic-chemical alterations serving as indicators of optimum ripeness. Respiration rate, ethylene and ABA are key regulators of fruit ripening in climacteric and non-climacteric fruits, respectively. In climacteric fruits, ABA interacts with ethylene, influencing the synthesis of ethylene itself. Although there is ample documentation on the involvement of hormones in fruit development and ripening, our understanding of the functions of various hormones throughout growth, maturation, and specific ripening processes remains incomplete.

Perennial fruit trees build their woody architecture with some building blocks, i.e. modular units, known as metamer or phytomer (White 1979; Room et al., 1992; Hare Krishna, 2012). It consists of meristems initially an apex. When a meristem faces periods of dormancy during low temperature or pruning, later it appears as bud, whenever active, as such bud produces a growing point with sequence of meristematic tissues simultaneously called a sprout, i.e. extension unit or growth unit (Halle et al., 1978; Bell, 1991). The driving mechanism behind the pattern appears to be auxin production (and basipetal transport) when new shoots and leaves developed and are exposed to light (Sterck, 2005). Other feature of trees are to produce more xylems relative to phloem, accumulate xylem over time and may thus produce thick woody branches and stems. Further, attaining reproductive phase and reproduction processes compete with vegetative functions, depleting resources necessary for maintenance and growth (Fakhri et al., 1987).

The idea that reproduction, growth and defence interact within the individual and compete for limited resource is now considered an established principle. Because there are trade-offs between a plant’s various functions and the concept of source, and sink helps to explain allocation patterns at both the physiological and evolutionary levels. Logical approaches have extended this hypothesis to an explicit as source and sink framework in which the effects of defence allocation on rates of consumption can be weighed against the effects on growth (Coley et al., 1985; Mooney and Gulmon, 1982; Fakhri et al., 1987). The allocation to vegetative structures has compounding interest for plant growth, as plant life-cycles begins with pure vegetative growth (Abrahamson, 1979), also consistent with the idea that perennials must forego some reproductive expenditure to retain sufficient resources for perennation.

Introduction
Ageing, a multifaceted and intricate process, is characterized by a series of transformations that occur at various levels of biological hierarchy, ultimately culminating in death. This phenomenon, marked by its complexity, involves numerous factors that interact simultaneously and operate across different levels of functional organization. The diversity of ageing phenotypes among individuals of the same species and the disparities in longevity
among different species underscore the significant roles of both genetic and environmental influences in shaping the lifespan.At its core, ageing is an ontogenic journey—a process of growing old that encompasses all physiological, genetic, and molecular changes occurring from fertilization to death. The biology of ageing pertains to the progressive accumulation of random molecular defects within tissues and cells, leading to age-related functional impairments in tissues and organs. This relentless, deleterious, and intrinsic phenomenon was famously described by Medawar in 1952 as an “unsolved problem in biology.” Despite the enduring mystery of the ageing process, research has advanced significantly since Medawar’s time, expanding our understanding of this intricate biological conundrum.
Goldberger et al. (2002) define senescence as the progressive deterioration of bodily functions over time, noting that normal human ageing is associated with a loss of complexity in various physiological processes and anatomical structures. Although ageing and senescence are often used interchangeably, they encompass distinct concepts. Senescence refers to a post-maturational process that leads to diminished homeostasis and increased vulnerability to death, while ageing encompasses any time-related process that begins at conception and continues until death. The mechanisms driving ageing are partially intrinsic, influenced by genetic and epigenetic factors, and partially extrinsic, shaped by environmental factors such as nutrition, radiation, temperature, and stress. Genetic factors account for approximately 25% of the variance in human lifespan, with the remainder determined by nutritional and environmental influences. 

Most of the plants undergo a period of rest, and in this period, the growth activities temporarily halt. The whole plant looses its aerial parts and undergoes a rest period in the form of rhizome, corm, or tuber. Researchers who study fruit trees use the term rest for dormancy (Samish, 1954). This period is sometimes called as quiescence. The term rest and quiescence can be included under common category dormancy. Some workers differentiate the term dormancy and rest period (Burton, 1964). Wareing and Co-workers (Robinson and Wareing, 1964; Wareing et al., 1964) isolated dormancy inducing substance in sycamore seedlings (Acer pseudoplatanus) which was named as dormin. Further, analysis of this substance by Cornforth et al. (1965) reveals that dormin was identical to Abscisin-II (a substance speeding the abscission of the young flowers of Lupinus luteus and have antiauxin effect).

Dormancy can be defined as an arrest in development of buds, seeds, embryos, or spores under conditions otherwise suited for growth (Taylorson and Hendricks, 1977). It is a survival strategy (exhibited by many plant species), which enables them to survive in climates where part of the year such as winter or dry seasons is unsuitable for growth. The dormancy may be due to the factors within the dormant organ or seed itself and it is called spontaneous dormancy. This type of dormancy is found in seeds, buds and perenating organs like tubers, bulbs, bulbils, corms and rhizomes. In some weeds, dormancy is caused by high or low temperature and this type of dormancy is called as imposed dormancy. Seeds normally germinate in darkness but are inhibited by light are considered to become dormant after exposure to light (Bewley and Black, 1982; 1985). Seeds that require light for germination are said to be photo dormant.

In general terms, dormancy can be defined as a period during the biological cycle of the plant in which growth of the whole organism (seed) or a plant organ (bud, tuber, corm etc.) is suspended eventhough the environmental conditions for growth may be favourable. More specifically, dormancy refers to a condition in which growth is inhibited by a restriction of essential metabolic processes, such as water uptake, gas exchange and cell division, either as a result of endogenous dormancy-controlling factors or in response to exogenous factors such as changes in the environment. It is distinct from a transient state of quiescence or rest imposed by an unfavourable environment in that dormancy persists even when the environment becomes favourable for growth whereas quiescence ceases.

For wild plants, dormancy has evolved as a means of enabling the plant to endure periods of stress due to drought or low temperatures and is therefore critical for the survival of the species. In cultivated arable or vegetable crops, breeding has generally led to a loss of dormancy or a reduction in the length of the dormant period. In arboreal crops of temperate climates, however, bud dormancy is still an essential feature of the annual growth cycle of the tree.

1. The word physiology was first used by Greeks around 600BC to describe a philosophical enquiry into natural things.

2. The word "physis" meaning nature.

3. The discovery of blood circulation by William Harvey in 1628.

4. C.Bernad (181378) who is considered as one of the founder of physiology.

5. The process of transport of an oxygen from outside air into the cells within tissues are called as Respiration.

6. STPD is abbreviated as standard pressure dry.

7. The gill arch along with the filaments is called as gill.

8. Haemoglobin is abbreviated as Hb or Hgb.

9. Cephalopods use haemocyanin- a copper containing protein for oxygen transportation.

10. Protobranch - the gill structure tends to occur in primitive groups and appears as a small leaf like structure.

Flowering is the most important phenological event in the phyotogerontology, as it is the key factor contributing to fruit production and profitability to the orchardists. Under favourable growth conditions the timing and intensity of flowering greatly determine the quantum of production. However, several times there are very contrasting florigenic events where despite prolific flowering, resultant fruit set remains low leading to low yields. Therefore understanding of the various external and internal factors involved in flower induction in mango is crucial for developing suitable orchard management practices to achieve regular and high yield.

Abstract

The availability of the quality seed is the first and the most important requirement which is of great relevance in tree improvement programme. Unlike agriculture, the forestry seeds have great variation in size, shape, dormancy, viability, moisture content, etc. It needs special techniques for collection, handling, processing and storage of the seeds of the large number of forest species. A strong commitment to improving tree seed technology is required for full utilization of seed supplies with the help of recent advances in seed physiology. Substantial improvements have occurred as a result of seed technology research offering the potential for major advances in traditional seed production and distribution systems.

Growth: Growth involve cell division subsequently cell elongation. Increase in volume that is associated with fruit growth largely result of cell division or cell elongation or both. In some fruit such as apple, extension of intercellular space may also contribute the growth. Generally growth by cell division in early stage whereas, cell elongation during later stage.

Two distinct type of growth curve are observed when increase in such variable such as fresh weight, volume and dry weight of fruit.

1. Single sigmoid curve
2. Double sigmoid curve

In case of single sigmoid growth curve firstly there is rapid increase in size then after decline so there is only one rapid growth is observed e.g. Apple, pear, tomato, cucumber and strawberry.

In case of double sigmoid two rapid growth period are separated by an intermediate period that is less growth or no increasing growth curve. Double sigmoid growth curve can be used as two successive sigmoid curve thus there are three clearly define stage of growth.

Fruit ripening is a highly coordinated, genetically programmed and an irreversible phenomenon involving a series of physiological, biochemical and organoleptic changes which finally lead to the development of a soft edible ripe fruit with desirable quality attributes. Ripening is the process where changes take place in the fleshy fruit and make it edible. It represents the unique coordination of developmental and biochemical pathways leading to changes in colour, texture, aroma and nutritional quality of mature seed-bearing plant organs (Barry and Giovannoni, 2007). Physiologically mature fruit is transformed from an unfavourable state of firmness, texture, colour, flavour and aroma to favourable state for consumption. It is the final phase in the development of fruit and involves major metabolic changes and it is normally an irreversible event. The ripening phase does not start until the fruit has developed considerably from the tissues present at anthesis and it is difficult to stimulate ripening before it attains maturity. The ripening changes which are common during softening are accumulation of pigments and changes in cell wall.

Fruits provide a suitable environment for seed maturation and often a mechanism for the dispersal of mature seeds. By anatomical definition, fruit is a mature ovary, and therefore, includes carpel tissues in part or in whole. However, many fleshy fruit species develop mature fruit tissues by including extra-carpellary floral components. The examples include strawberry, pineapple, mulberry and pome fruit (apple, pear, etc.) in which the receptacle, bracts, calyx and floral tube (the fused base of floral organs), respectively constitute majority of mature fruit tissues. Even species with fruit derived from carpel tissue exclusively can display a range of developmental programs, spanning the relatively uniform single expanded carpel or drupe of stone fruit to the differentiated carpel tissues, giving rise to the peel (flavedo) and multi-carpel flesh as observed in citrus and banana. Although genetic selection of agriculturally valuable fruits is being done since centuries but most of the information about how fruits develop, how this development is coordinated with embryonic development and seed formation and the molecular, cellular and physiological events that control fruit growth and differentiation are still lacking. In the following sections, the various aspects controlling fruit setting and development have been discussed.

Introduction
The genetic code and protein synthesis are fundamental processes that underlie the
expression of genetic information within all living organisms. These processes are integral
to understanding how DNA, the hereditary material, dictates the production of proteins,
which are essential molecules that carry out various functions in the body, from structural
support to catalyzing biochemical reactions.
Genetic Code
The genetic code consists of rules that guide the translation of information stored in
DNA or RNA sequences into proteins within living cells. It is nearly universal across
all organisms, underscoring the shared evolutionary origins of life. The genetic code is
composed of codons, which are sequences of three nucleotides in mRNA (messenger
RNA) that correspond to specific amino acids or stop signals during protein synthesis.
Each of the 20 amino acids used in protein synthesis is encoded by one or more codons.
For instance, the codon AUG not only codes for the amino acid methionine but also serves
as the start signal for translation, marking the beginning of a protein-coding sequence. The
redundancy of the genetic code, where multiple codons can specify the same amino acid,
provides a protective mechanism against mutations, as some changes in the nucleotide
sequence do not alter the resulting protein.
Protein Synthesis
Protein synthesis is the process by which cells construct proteins based on the instructions
encoded in mRNA. This process takes place in two primary stages: transcription and
translation.
Transcription: Transcription is the first step of gene expression, where a particular segment
of DNA is copied into RNA by the enzyme RNA polymerase. During transcription, one
of the two DNA strands serves as a template for the formation of a complementary RNA
strand, This newly synthesized RNA strand, known as pre-mRNA, undergoes further
processing, including splicing, capping, and addition of a poly-A tail, to become mature
mRNA, which is then exported from the nucleus to the cytoplasm in eukaryotic cells. In
contrast, in prokaryotes, both transcription and translation occur within the cytoplasm.

Most food legumes have a long history of domestication almost as long as cereals, and during this time they have been subjected to conscious and unconscious selections for better adaptation to environmental condition as well as better seed yield. In general, crops during their ontogeny faces a number of abiotic stress viz., excessive and/or low soil water stress, soil salinity stress, high as well as low temperature stress. It has been well documented that crop yields would be greater in many cropping regions if more water were available. 
Availability of water for agriculture is being challenged increasingly because of growing demand for water from other sectors such as industry, urban use, and for social and environmental purposes. Water stress may conceivably arise either from an insufficient or from an excessive water activity in the plant’s environment. Many physiological characteristics are correlated with the water potential of mesophyll tissue but the correlations are species specific. There is a general hierarchy of sensitivities among general physiological activities. Most sensitive are cell expansion, cell wall synthesis, protochlorophyll formation, and nitrate reduction. Generally turgor pressure is still accepted as the best indicator of water stress in plants. The specific mechanism by which turgor regulate physiological function probably relate to cell walls and membranes. Cell membrane structure, and spatial arrangement of enzyme, transport channels, cellulose synthesis rosettes, and receptor proteins may be dependent on turgor pressure.

Introduction
Cell Cycle: Growth at the cellular level involves the cell cycle, which includes phases of growth (G1), DNA replication (S), and cell division (M). During these phases, cells prepare for and execute division to increase cell numbers. Mitosis and Meiosis: Mitosis results in two identical daughter cells, crucial for tissue growth and repair. Meiosis, on the other hand, is essential for producing gametes (sperm and eggs) and ensures genetic diversity.
Hormonal Regulation
Growth Hormone (GH): Secreted by the pituitary gland, GH stimulates liver cells toproduce insulin-like growth factor 1 (IGF-1), which promotes cell growth and division throughout the body.
Thyroid Hormones: Thyroxine (T4) and triiodothyronine (T3) from the thyroid gland regulate metabolic rate and are vital for normal growth and development, particularly in the nervous system.
Sex Hormones: Estrogens and androgens influence the growth of secondary sexual characteristics and contribute to the final stages of skeletal growth during puberty.
Nutritional Factors
Proteins: Amino acids from dietary proteins are necessary for the synthesis of new proteins and enzymes, which are crucial for cell growth and repair.
Vitamins: Vitamins such as A, C, and D are essential for various growth processes. For instance, vitamin D is vital for bone growth and calcium absorption.
Minerals: Calcium and phosphorus are key for bone development, while zinc and iron are important for cellular functions and overall growth.
Genetic Factors
Genetic Blueprint: Growth patterns and potential are largely determined by genetic factors. Genes influence growth rates, final height, and the development of various body structures.
Growth Disorders: Genetic mutations or abnormalities can lead to growth disorders such as dwarfism or gigantism, illustrating the role of genetics in growth regulation.

Introduction
Intracellular transport of molecules plays a crucial role in maintaining cellular function and organization. The genetic and biochemical processes that regulate membrane trafficking, such as membrane bending, budding, fusion, and fission, ensure the efficient movement of molecules within cells. Despite substantial advances in understanding the molecular aspects of these processes, the broader, or “supramolecular,” regulation of membrane trafficking, which coordinates the overall balance and response to environmental changes, remains less explored. This involves the transport and exchange of membranes and proteins betweenorganelles in a highly organized manner, critical for maintaining cellular homeostasis.
Membrane Trafficking Pathways
Membrane trafficking consists of well-defined pathways connecting cellular compartments like the endoplasmic reticulum (ER), the Golgi apparatus, and the plasma membrane (PM). Proteins and lipids are transferred from the ER to the Golgi and then directed either to the PM or other intracellular destinations. These pathways must be tightly regulated to maintain cellular balance, as any disruptions in membrane flow can lead to cellular dysfunction. In addition to routine cellular maintenance, these pathways must adapt to signals from the environment, ensuring that cells respond appropriately to external stimuli.

Many horticultural and forestry plants don’t come true-to-type when propagated by seed owing to cross pollination and highly heterogeneous nature of fruit crops, in general. As a result, when such plants are grown, the individuals differ in morphological as well as fruit characteristics as compared to mother plant. Though, it was a common practice in old days to establish new orchards with seedling plants, but now with the development and standardization of different vegetative propagation techniques, such plantings are avoided. In modern system of crop production, instead of a single tree derived from seed, use of composite plants (consist of usually scion and rootstock, joined together by budding or grating) is in vogue. This could have been possible by growing interest of mankind in vegetative means of plant propagation.  In asexual propagation, vegetative parts of the plant are used for propagation.  It is practicable because all the living cells of a plant have a capacity to regenerate into a full plant under favourable environmental conditions.

Selye, H (1936), the pioneer in stress physiology, defined stressors as noxious stimuli that increase adrenocorticotropic hormone and clubbed these stimuli under the term stress. Rivier and Rivest (1991) and Chrousos and Gold (1992) defined stress as “a state of disharmony, or threatened homeostasis.” Stress challenges homeostasis, but does not disrupt it, in an adapting organism. McEwen (2000) defined stress as a “real or interpreted threat to physiological or psychological integrity that results in physiological and/or behavioral responses.” The following are the various stressors:

Domestic animals including chicken and mammals, belong to the category of homeotherms, as opposed to poikilotherms. Homeotherms or warm blooded animals are those which are able to maintain constant body temperature in the face of varying environmental temperature. The poikilotherms or the cold blooded animals change their body temperature according to the temperature of the surroundings. Most invertebrates and lower vertebrates belong to the category of poikilotherms.

Why do animals have to maintain constant body temperature? As we are aware that enzymatic reactions in the body are temperature sensitive. In fact, a 10 degree centigrade increase in temperature can result in doubling of the reaction rates. In order to maintain optimum functioning of the enzymatic reactions in the body a constant temperature is required. This constant body temperature is not very constant in the sense that it varies somewhat during exercise and also when the animal is exposed to extremes of temperature of the surroundings. That means that the temperature regulation mechanisms in the body are not 100 percent perfect.

At this stage it is desirable to clarify the distinction between surface temperature and core temperature. The surface temperature, in contrast to the core temperature rises and falls with the temperature of the surroundings. It is the temperature of the deep tissues or internal organs which remains constant. The temperature of the rectum is usually taken as a useful indicator of core temperature because of the ease of measurement. The rectal temperature of several domestic animals is given in Table 1.

Domestic animals –including chicken and mammals, belong to the category of homeotherms, as opposed to poikilotherms. Homeotherms or warm blooded animals are those which are able to maintain constant body temperature in the face of varying environmental temperature. The poikilotherms or the cold blooded animals change their body temperature according to the temperature of the surroundings.

Presently, potato (Solanum tuberosum L.) is the world’s third most important crop, after wheat and rice. Tubers of the potato plant have been used as a primary nutritional staple and a carbohydrate source in many diets and as the basis for a variety of processed products throughout the world. Owing to climate change, potato production is expected to fall in the coming decades, predictions asserting that global potato yields will decrease by 9–18% in most parts of the world. Availability of new varieties less sensitive to these environmental cues is thus crucial to overcome the negative effects of global warming. Of various developmental phases, tuberization is the most sensitive stage in potato limiting its climate associated geographical distribution and actual yield.  Hence, understanding the tuberization process becomes even more important in the face of changing global climate. The induction of tuber formation is a key developmental transition for the production of potatoes.  Understanding the regulation of tuber induction is essential to devise strategies to improve tuber yield and quality.

Physiotherapy may be defined as the use of physical techniques like massage, exercise, heat, cold, sound waves, electric current etc for the treatment of injuries and movement dysfunction. Physiotherapy deals with the treatment of diseases by physical methods. It is used for treating injuries, strain, spasm, painful conditions, sprain of tendons, paralysis, postoperative trauma etc. It improves functioning of nerve, muscles and bones. The aim of physical therapy is the restoration of function and promotion of tissue healing by assisting normal physiological processes. The physiological response to physical therapy is its effect on the vascular supply; this in turn reproduces similar changes in deeper tissues.

Mycotoxins are naturally occurring toxic secondary metabolites produced by molds. More than 25% of world’s food crops are contaminated with mycotoxins (Eskola et al., 2020). Like other environmental pollutants, mycotoxins also harm the health and productivity of animals and poultry. Mycotoxin development typically occurs in the field, during feed processing and storage under unfavourable conditions. Factors such as temperature changes, storage time, and conditions play a crucial role in fungal growth and aflatoxin synthesis.

Introduction
Aquaculture has grown into a significant business and is the fastest-growing agricultural production sector in the world, taking new, intense, and diverse directions (Villa-cruz et al., 2009). Aquaculture has experienced intensification in recent years attributable to escalating stocking densities and excessive feed utilization, which have imposed stress on aquatic organisms and ultimately inhibited their growth and immune functionality. Chemotherapy remains a principal approach for the treatment and prevention of aquatic diseases. Nevertheless, a plethora of scholarly articles have indicated that chemical therapeutics exert adverse effects on both human health and ecological systems. The aquatic environment is adversely affected by antibiotics and their residuals, as a significant proportion of bacterial strains are developing resistance to these pharmaceuticals within the ecosystem. Consequently, there has been a concerted emphasis on the exploration of environmentallysustainable alternatives (Kumar et al., 2020). The public increasingly recommend natural compounds, while the utilization of synthetic chemicals, hormones, and antibiotics is increasingly becoming impractical owing to consumer apprehensions and stringent regulatory frameworks in numerous nations (Chakarborty et al., 2014).
Phytobiotics can be conceptualized as products originating from plants that are incorporated into animal feed to optimize performance in aquatic species. Predominantly, leaves, roots, tubers, or fruits of various herbs, spices, and other botanical sources may be utilized as phytobiotics (Arts and Hollman, 2005). These substances are typically employed to promote enhanced growth performance in the cultivation of shrimp and fish. Based on their processing characteristics, phytobiotics are divided into categories:

The poultry industry in India is experiencing rapid growth, with meat production and egg production increasing by 5.13% and 6.77%, respectively, in 2022-2023 compared to the previous year (BAHS, 2023). Numerous factors and challenges impact poultry production on a global scale, such as intense international competition, evolving consumer attitudes toward food safety, animal welfare, and environmental conservation. Poultry commonly harbor infectious diseases that can also affect humans, with many of these zoonotic diseases having reservoirs in mammalian species other than humans, adding complexity to their management.

Phytobiotics are plant derivatives such as herbs, plant extracts or spices and have a wide range of activities such as stimulation of feed intake, growth and endogenous secretions in the gut. They act as immunomodulators resulting in decreased mortality and also have coccidiostatic, anti microbial, anthelminthic and anti-inf lammatory activities. Phytobiotics also possess hepatoprotective and hepatogenic properties, which tone up liver resulting in increased nutrient utilization and better performance. Herbs like Achyranthes aspera (Prickly Chaff Flower, Devil’s Horsewhip, Apamarga), Andrographis paniculata (Green chirayta, King of bitters, Kalamegha), Azadirachta indica (Neem), Boerhaavia diffusa (Spreading Hogweed, Punarnava), Eclipta alba (False Daisy, Bhringaraj), Ichnocarpus frutescens (Black creeper, Utpalagopa), Terminalia chebula (Black myrobalan, Haritaki). These herbs have hepatostimulant, hepato-protective, immunomodulatory and antioxidant activities (Sadekar et al., 1998; Manu and Kuttan, 2009; Michels et al., 2011, Dash et al., 2007). Further, they optimize digestion and metabolism resulting in better protein utilization, improved mucosal function and reduced cost of metabolic deamination. Andrographolide and 14-deoxy-11, 12-didehydro-andrographolide isolated from Andrographis paniculata inhibits free radical activities and lipid peroxidation. Inhibition of lipid peroxidation in meat prevents free radical production thereby preserving meat composition, colour and improvement in shelf life. In addition, it has been studied that a herb Terminalia chebula helps to reduce stress (Selvakumar et al., 2007).