eBook Chapters

Structure of matter: every structure is made up of elements. Elements can join together to make compounds. The smallest particle of a compound is a molecule. The periodic table gives details of all elements.

Nucleus: the center of atom containing protons and neutrons and hence almost whole mass of the atom. 

Atom: the smallest units of matter composed of electrons are negatively charged, protons have a positive charged and neutrons are neutral. If there are more electrons atom will be negatively charged, if there are more protons it will be positively charged. The total charge of electrons is equal to protons and hence the atom is electrically neutral.

Analytical Reagents

Chemical reagents are supplied in different grades and each grade has a distinct purpose and range of uses. The purest grade is analytical reagent (AR), the second is laboratory reagent (LR), the third is guaranteed reagent (GR) and fourth is technical grade. Second and third form of reagents have a lot of impurities. Therefore, for the determination of micronutrients, AR grade reagents should be used.

Distilled Water

Distilled water is always used in chemical analysis. The quality of distilled water varies from single distilled water to double or triple distilled water depending upon the requirement of analytical technique(s) e.g. double distilled water (glass distilled) is always recommended for micro nutrient and heavy metal analysis.

All control measures are directed to bring down the nematode population low enough to raise the crop successfully and profitably. The choice of control measures to be taken depends upon the nematode species to be tackled and the crops involved.

1. Cultural methods 
The objective of these methods is to adopt suitable land management practices, so as to bring down the nematode population in the field to a low level, which may not cause economic injury to the crop or to keep the field free from parasitic nematodes by adopting suitable preventive measures. Besides causing direct damage to the crops, several nematode species are known to transmit many fungal, bacterial and viral pathogens, which aggravate the extent of damage caused to the crops. Many of these pathogens gain access to the host plants only through mechanical injury caused by the nematodes. By controlling the nematode parasites, the incidence of diseases caused by such phytopathogens can also be avoided to a large extent. Cultural methods, though may not give spectacular results within a short span of time of a single season or year, as in the case of chemical control measures, if followed over a number of years is sure to give encouraging results. Cultural methods include crop rotation, fallowing, ploughing, flooding, trap cropping, use of organic amendments, selection of seeds and seed materials, use of resistant and tolerant varieties etc.

In most of the underdeveloped and developing countries, regional diets are monotonous, unbalanced and poor in quality having a high percentage of starchy components and inadequate proportion of protein. The long-term solution to the problem of protein malnutrition lies in the greater production and better distribution of a protein-rich diet. Fish offers protein in a cheap and alternative form. Probably due to this, man has exploited the hydrosphere for food and consequently the history of the development of pisciculture. As the fish perishes rapidly, methods have been devised to keep the fish fresh between the catch and consumption.

The development of fisheries in India has attained considerable progress in increasing the per hectare yield of carps by controlled breeding and rearing of the young ones. Keeping the pace of development, the culture of air-breathing fishes has attracted the attention of aqua-culturists. Many varieties of these fishes have been successfully bred using pituitary extract (Ramaswami and Sundararaj, 1957; Moitra et al, 1979; Thakur, 1976). The traditional methods of transport of spawn, fry, fingerlings and even brooders in various open and closed systems pose major problems due to their heavy mortality. The mortality of live fishes is high mostly due to stress during transportation. For a long, studies on different aspects of transportation of carps and their allies have been carried out by fishery scientists. Some of the works which need special mention are that of Khan (1939, 1946), Ganapati and Chako (1951), Ranade and Kewalramani (1956), Saha and Chowdhury (1956), Saha et al, (1956a and b), Ramchandran (1969), Singh (1977), Selvaraj et al, (1981) and Jha (1995) etc. In comparison to Indian major carps, consumption of air-breathing fish is not so popular although they are a rich source of protein. However, their demand is gradually increasing. Much has to be done to meet the increasing demand of air-breathing fishes to exploit the maximum available derelict water.

The two commercially important Indian air-breathing fishes, Anabas testudineus (Bloch) and Channa punctatus (Bloch) commonly known as climbing perch and snake-headed murrel belong to the order Perciformes and Channiformes respectively. They live in different trophic zones of swamps and derelict ponds and are highly predatory habits. In the present work, oxygen uptake has been observed in Anabas testudineus and Channa punctatus concerning their body weight and group size. The effect of anaesthetic on the oxygen uptake and the effect of ammonia on the structure and function of the gills in Channa punctatus have also been studied. The findings have been used to evaluate suitable methods for long-distance transportation of these fishes. As we surviving in the COVID-19 pandemic, proper sanitization of all the equipment and accessories is one of the essential steps for fish transportation.

The term ecology was first of all proposed by zoologist H. Pietir in 1865. It was derived from the Greek word ecologic means oikos = living place and logos = study and some definitions of ecology presented below:

1. According to Ernst Haeckel, 1869 “The total relations of the animal to both its organic and inorganic environment is called as ecology”.
2. E. Warming 1895 “Ecology is the study of animals and plants in relation to their environment”.
3. According to Odum 1963 “Study of structures and functions of nature is defined as ecology”.
4. Krebs 1985 says that the “Ecology is the scientific study of interaction that determine the distribution and abundance of organisms”.

The life of insects is dependent on the adaptability of the environment, if the environment is unfavourable then the insect population ceases and vice-versa. This insect move one place to another to get the favourable environment so that they can pull on their life activities properly. There is a deep relationship between the living community and non-living environment. Both are affecting each other greatly. This inter-relationship between living community and non-living environment is called as ecosystem. The term ecosystem was first used by A.G. Tansley as early as 1935 and he defined, “Ecosystem is the system of resulting from the interaction of all the living and non-living factors of the environment”.

1.1 Historical background of the Embryology

Embryology is a branch of Anatomy. It is the study of growth and differentiation undergone by an organism in the course of its development from a single fertilized egg cell into a highly complex and independent living being like its parents. It explains how one develops before he is born. Important changes also take place after birth and continue to occur even to adult stage. eg: Replacement of RbC and WbC is a continuous developmental process and reverting to activities seen in prenatal condition is seen in healing of wounds. So the term ‘Developmental Anatomy’ which includes prenatal and postnatal development is preferred over term embryology as Developmental Anatomy, includes prenatal and postnatal development and as the term embryology refers truly prenatal (Intra uterine) development.

Aristotle (384-332/322 BC) proposed two theories regarding origin of life

Q. 1 Choose the most appropriate word from the options given below to complete the following sentence:
His rather casual remarks on politics ………. his lack of seriousness about the subject.
(A) Masked        (B) Belied
(C) Betrayed       (D) Suppressed

Plant oils are obtained from their plant hosts through a variety of processes commonly called Extraction process. Essential oils are extracted from different parts of the plants. The quality and quantity of the oil is mainly depends on the method of extraction and the quantity of the raw materials used. For example, Lavender is extracted from its flowers, Orange from the rind of its fruit, Frankincense from the resin of its tree, Cinnamon from its bark, Pine from its needles, clove from flower buds and so on. Production of a good quality essential oil, the cultivation factors also play a vital role like soil quality, climatic and geographic conditions etc. As example, Jasmine flowers must be picked by hand at dawn on the very first day they open. A Sandalwood tree must be 30 years old and 30 feet high before it is ready to produce its best quality oil. Further the quantity of the plant materials are also matters for the price and quality of the essential oil. As an example, it takes roughly 12,000 Rose blossoms to produce 5 ml of Rose. Whereas it take 100 kilos of Lavender leaves to produce 3 liters of Lavender. As a result Rose is roughly 24 times more expensive than Lavender.

Horticulture word derived from Latin word: Hortus meaning ‘Garden’ and cultura means ‘cultivation’.

Father of horticulture: Thomas Andrew Knight, John Lindley, Liberty Hyde Bailey.

1^st artificial hybridization in fruit crop in world: T. A. Knight.

Father of vegetables: L. H. Bailey.

1^st book in horticulture: Fruit growing in India: W.B. Hayes (1945) & related to litchi.

Export growth of fresh fruits and vegetables in term of value is 14% and of processed fruits and vegetables is 16.27%.

Contribution of horticulture sector to agriculture GDP (2013-14): 29%.

India is largest producer of Coconut, Cashew, Tea and Spices.

Definition of farmer (National Policy for Farmers, 2001): A person actively engaged in the economic and/or livelihood activity of growing crops and producing other primary agricultural commodities and will include all agriculture operational holders, cultivators, agriculture labourers, share croppers, tenants, poultry and livestock rearers, fishers, beekeepers, gardeners, pastoralists, non-corporate planters and planting labours, as well as persons engaged in various farming related occupations such as sericulture, vermiculture, and agroforestry. It also includes tribal families/ persons engaged in shifting cultivation and in the collection, use and sale of minor and non-timber forest produce.

2.1. What is Greenhouse Technology?

Greenhouse technology involves primarily the structural design that can take care of climate control mechanisms to create proper micro-crop-climate and secondarily it involves the technology needed for optimum growth and production of crop grown under this structure. Combination of these two aspects may be expressed as ‘greenhouse technology’.

So the ‘greenhouse technology’ may be defined as “The technology required to built a structure, covered fully, partly or porously for manipulating the inside climatic conditions, under which crops/plants can be grown with special measures”.

Introduction
Project title:
Objective (S):

1. Proteins in solution absorb ultraviolet light with absorbance maxima at 280 and 200 nm. Amino acids with aromatic rings are the primary reason for the absorbance peak at 280 nm. Peptide bonds are primarily responsible for the peak at 200 nm.
2. Aromatic amino acids tyrosine and tryptophan give proteins their characteristic ultraviolet (UV) absorption at 280 nm, which is routinely used to estimate protein concentration. Phenylalanine and disulfide bonds also contribute to absorption at 280 nm, albeit slightly.

1.1. Introduction

The significance of milk as the most wholesome single food available in nature has never been debated. It is as ancient as mankind itself, as it is the substance created to feed the mammalian infant. All species of mammals, from the lowly rat to the mighty whale, produce milk for this purpose. Several centuries ago, perhaps as early as 6000-8000 BC, ancient man learned to domesticate species of animals for obtaining their milk for consumption. These included cows, buffalos, sheep, goats and camels, all of which are still used in various parts of the world for the production of milk for human use (Fig. 1.1 & 1.2).

Physiological plant disorder is caused by non-pathological conditions such as poor light, weather damage, waterlogging or lack of nutrients affect the operation of the system caused. Physiological condition selected from diseases caused by plant pathogens such as viruses or fungi to distinguish. Although the physiological disorder symptoms may occur such as disease, they can often be prevented by changes in environmental conditions. However, once the nutritional deficiencies of plants showing symptoms, is likely to return that season yield will be reduced.

Inland fisheries are important global contributors to food security, livelihoods, and ecosystem services. A report on the global snapshot of expert-perceived impacts of COVID-19 on inland fisheries has been submitted by Stokesa et al, (2020). They studied an online survey to determine perceptions of Inland fisheries pressures between June and July 2020. They also analysed pandemic impacts on inland fisheries, based on the responses analyzed against fish capture and human development index data.

Hypothesis become theories and theories attain rank of laws after withstanding rigorous experimental tests. Feasibility of a process is confirmed in the laboratory. Qualitative and quantitative analyses give complete chemical picture of the substance. It is with these considerations in mind we proceed to learn what is there in a laboratory.

Volumetric Analysis Precautions

1. Use Clean Glassware: Ensure all glassware, such as burettes, pipettes, and volumetric flasks, is thoroughly cleaned and rinsed with distilled water to avoid contamination and ensure accurate measurements.

2. Clean Glassware Properly: Before use, all glass apparatus should be thoroughly cleaned with a cleansing mixture of potassium dichromate (K2 Cr2 O7 ) and concentrated sulfuric acid (H2 SO4 ) to remove any residual contaminants. After cleaning, rinse the glassware thoroughly with distilled water to ensure no traces of the cleansing mixture remain.

3. Proper Calibration: Calibrate all measuring instruments, including burettes, pipettes, and balances, before use to maintain accuracy in measurements.

4. Avoid Parallax Error: When reading the meniscus level in a burette or volumetric flask, ensure the eye is at the same level as the meniscus to prevent parallax error.

5. Use Correct Indicators: Choose the appropriate indicator for the titration based on the type of reaction and the pH range of the endpoint to ensure precise determination of the endpoint.

Nature has made such a beautiful system that a fruit does not spoil unless its outer covering is removed and till it is there on the plant. For example banana will not spoil for long time if we do not remove its peel. Similar is the case with apple, guava, mango and many other fruits and vegetables. But as soon as the outer covering is removed the damage begins and the commodity is spoilt very soon.

Preservation is extending shelf life of fresh or processed food by using various methods and prevention or reduction of spoilage. Better the preservation, lesser the spoilage, more the spoilage poorer and inefficient is the preservation.

Therefore, in order to prevent or reduce the spoilage, we have to first identify and understand the causes of spoilage. There are chiefly 3 agencies that cause spoilage in fruits and vegetables i.e. (i) microorganisms, (ii) enzymes & chemical changes and (iii) man, animals, rodents, insects, etc. For effective preservation we have to check the growth and activity of these spoilage causing agencies. So, in order to prevent spoilage and preserve a perishable commodity for long time the following principles and methods are to be followed.

3.1. Introduction

Food preservation can be defined as the science which deals with the process of prevention of decay or spoilage of food thus allowing it to be stored in a safe condition for future use. Scientifically, preservation may be defined as a science which deals with the process for prevention of decay. All foods gradually undergo deterioration or spoilage from the time they are harvested or manufactured. Some commodities spoil rapidly, while others can keep for longer but limited periods. Spoilage in the food products may be caused due to some physical, chemical and microbial changes during storage. The preservation of these products can be resulted by controlling following physical, chemical and microbial changes.

Analytical Chemistry

The science involving the determination of the constituents in terms of elements and compounds is called Analytical Chemistry. It is used to identify the substances found in a material and to quantify the exact amount of substances in them.

The basic principles involved in Analytical Chemistry are changes takes place in the substances by the process of combination, decomposition, replacement and double decomposition.

Body Parts of Farm Animals

It is important to know about the various terms used to indicate different body parts of the animals so that whenever a description of the animal/body part is presented, one could specifically understand it. Some of the terms used to point out different body points of common livestock species have been shown in Figure 2.1.1-2.1.5. Terms which are more frequently used for different livestock species have been depicted in Table 2.1.1.

Introduction

The microorganisms exist as single cell or cluster of cells capable of orderly growth, metabolism and reproduction in two identical daughter cells. These includes cellular organisms {protozoa, algae and fungi (Eukaryotes), bacteria and archaea (Prokaryotes)} and viruses (non cellular entities). The study of microorganisms contribute to understanding of :

1. Basic biological sciences - It acts as a tool for providing the basic information for life processes. The discovery of DNA, RNA, proteins and enzyme functions all came from microbial study.
2. Applied biological sciences - Medicine, agriculture, industry, plant and animal pathology, immunology, plant and animal nutrition, biotechnology all have origin from the understanding of the cell function and metabolism of microorganisms.

A pH meter is very commonly used for the measurement of the reaction of a solution or a medium. The pH determination with the help of a pH meter is based on the measurement of the electromotive force (e.m.f) of a pH cell consisting of an electrode sensitive to W ions and a reference electrode.

Current Status of Seed Production

Organized seed production in the country became possible with the formation of National Seed Corporation (NSC) during 1963, which paved the way for a sound seed industry to come as a consequence of the introduction of hybrid technology during 1961-65. The release of high yielding dwarf varieties of wheat and rice by the 1960’s gave further impetus to the growth of the seed industry in the country. For the total area under cultivation of 26.7 m hac and 44.8 hac of wheat and rice respectively, the seed requirement for these two crops alone come to 32 lakh tones and 13 lakh tones respectively of which the varieties contribute about 98 per cent and the hybrids 2 per cent. Only about 10-15 per cent of the total requirement is met by the seed producers leaving the balance for the farmers to manage and the seed producers have to grab the opportunity to supply quality seed materials in order to increase the production.

Current Status of Seed Production

Organized seed production in India became possible with the formation of National Seed Corporation (NSC) during 1963, which paved the way for a sound seed industry to come as a consequence of the introduction of hybrid technology during 1961-65. The release of high yielding dwarf varieties of wheat and rice by the 1960’s gave further impetus to the growth of the seed industry in the country. For the total area under cultivation of 26.7 m ha and 65 per cent of the area) insect, disease and weeds (10-40 per cent loss) and also poor shelf-life. Hybrid technology have defined solution in several crop plants specially vegetables, cotton, rice etc. with the development of appropriate hybridization and seed production. In 1990-91, the area planted to ‘bought seed’ was about 10.35 per cent. The total ‘bought seed’ was estimated at around 5.91 lakh tonnes valued at Rs 679.80 crores. 

Pesticide poisoning occurs when a pesticide enters the body and interferes with the vital systems of the body. Symptoms can begin anything from 1/2 hour to 24 hours after exposure. The typical symptoms and signs of pesticide poisoning are:

Pesticide poisoning occurs when a pesticide penetrates the body and disrupts its essential systems. Symptoms can appear anywhere from a half hour to 24 hours following exposure. The common symptoms and indicators of pesticide poisoning are:

Initial symptoms may include

First Aid

First aid is the preliminary care of a person who has been exposed to pesticides before getting proper medical attention. The initial step is to remove the person from the source of the exposure by removing pesticide from their skin, removing contaminated clothing, or transporting them to fresh air. Be careful not to contaminate oneself throughout this process.

Pesticide on the Skin

• Remove any contaminated clothes.

 • Drench clothing and skin with plenty of water.

• Clean hair and skin with soap and water.

• Dry the victim and wrap them in clean clothes.

• Prevent the victim from being chilly or overheated.

INTRODUCTION

Plant pathogens induce diverse reactions in the body of their hosts. This result in creation of abnormalities which become visible on the plants. A visible or otherwise detectable expression of abnormal physiology, development, or behaviour in a plant resulting from disease is called symptoms. Normally, a distinction is made between symptoms and signs A symptom of disease is expressed as a reaction of the host to a causal agent, where as, a sign is evidence of disease other than that expressed by the host. Signs are usually the structures of the pathogen.A disease is first noticed by the presence of symptoms and /or signs, and recognition of specific type of symptoms or sign aid in the eventual diagnosis of the disease.

1 The changes in functioning at the cellular level and establishment of disease process is termed

a) Pathogenesis b) Virulence

c) Prognosis d) None of the above

The general systemic states are generalized in nature and involve whole body systems. They are common to many diseases and contribute to the pathogenesis
of the disease. Pathogenesis is defined as the changes in functioning at the cellular level and establishment of disease process. Hyperthermia,
hypothermia, fever, toxaemia, septicaemia, bacteraemia, shock, dehydration, acid-base imbalance, hyponatremia, hypokalemia etc. are some examples of
general systemic states.

Definitions

        Toxicology: Knowledge (or science) of poisons, including their chemical properties, identification, biological effects, and the treatment of conditions they cause.

        Poison: Any solid, liquid, or gas that, when introduced into or applied to the body, can interfere with the life processes of cells of the organism - by its own inherent chemical properties - without acting mechanically and regardless of temperature.

Definitions
 
    •    Toxicology: Knowledge (or science) of poisons, including their chemical properties, identification, biological effects, and the treatment of conditions they cause.

    •    Poison: Any solid, liquid, or gas that, when introduced into or applied to the body, can interfere with the life processes of cells of the organism - by its own inherent chemical properties - without acting mechanically and regardless of temperature.

    •    Poison = Toxicant: The term poison is now used less often. Reason: Historical application of the term (malicious) vs. a compound used as a feed additive, agricultural, or other chemical - manufactured to fulfill a perceived human need.

We may study the nutrient metabolism in a better way as explained in the following summarized form in Table 1.

Historical Development of Soil Science/Agriculture

Francis Bacon (1561-1624 A.D.): Found the water as nutrient of plants.

Van Helmont (1577-1644): Give the ideas about the role of soil as a simple source of water and minerals for the plants.

Section-A : Write True / False

Q.1 The moment generating function (m.g.f) of a random variable X (about origin having the probability function f (x) is defned as

Abstract

Rural women play a vital role in farming system operations and contribute substantially in the physical aspect of farming, livestock management, postharvest and allied activities. Around 43% of the agricultural labour force of developing countries is composed of women dependency. India has achieved self sufficiency in agricultural production, but a considerable amount of production gets spoiled in every year due to inadequate post-harvest management, processing, infrastructure and skill. To uplift the livelihood and economic conditions of the rural women there is an urgent need to impart trainings for skill development regarding the value addition of horticultural crops. This offers tremendous opportunities for women occupation but also inculcate entrepreneurial characteristics in them. Trainings and skill development are useful for rural women as they can add more value to the seasonal fruits and vegetables and generate varieties of products namely Pickle, Murabbaa, Chutney, Jam, Sharbat etc. These efforts enhance their family income by around 30-40 thousands per annum as they fetch more prices of raw produce after processing. Moreover during peak production times glut only promote produce and profit loss. Instead of direct marketing of their produce they can do value addition of their produce and then sell them in market, it not only increases the value of their products but the prices also enhance by many folds. After giving training to rural women, they are motivated to go for self marketing of their produce at domestic and village level. Similar way these trainings can transform the life style and income level of farming families comprehensively.

Introduction

Spectral signature: A spectral signature is the unique pattern of reflection and emission of a target at different wavelengths. This difference helps to classify remote sensing images based on the spectral signatures of different objects.

Electromagnetic (EM) spectrum: The EM spectrum is the range of all types of EM radiation. Some examples are visible light from a lamp, radio waves from a radio station, microwaves, infrared light, ultraviolet light, X-rays, and gamma rays.

Spectral response patterns: A spectral response pattern is the amount of energy that an object reflects or emits at different wavelengths. It shows how the object interacts with the EM radiation.

Generation system of seed multiplication is nothing but the production of a particular class of seed from specific class of seed up to certified seed stage. The choice of a proper seed multiplication model is the key to further success of a seed programme. This basically depends upon,

• The rate of genetic deterioration
• Seed multiplication ratio
• Total seed demand (Seed replacement rate)

ABSTRACT

Of the total production of the crop yield, only 63 per cent is available for human consumption. The remaining is lost in more or less equal proportions to weeds, pests and diseases. Prior to genetic engineering, the exchange of DNA material was possible only between individual organisms of the same species. In the field of agriculture for instance, farmers have continuously modified naturally occurring species through seed selection and controlled breeding. With the advent of the recombinant DNA technology, it has however been possible to identify specific genes associated with desirable traits in one organism and transfer those genes within and beyond the boundaries of species into other organisms.

1. Genes for herbicide resistance

Modern agriculture has developed a range of effective herbicides to tackle the effects of weeds on crop yield. Some of the most useful of these are broad-spectrum herbicides because they are active against a wide range of weeds. However, these can only be used at times when the crop is not itself vulnerable to herbicide action. The development of herbicide-resistant crops therefore offers the opportunity to spray crops at the most effective time to kill weed species without damaging the crop plants. By definition, herbicides are much more toxic to plants than to animals. Therefore, it is not surprising that they generally affect ‘plant-specific’ biological processes. The herbicidal activity of many herbicides has been found to result from the specific inhibition of a single enzyme/protein. The following are four distinct strategies for engineering herbicide resistance: i. Overexpression of the target protein, ii. Mutation of the target protein, iii. Detoxification of the herbicide, using a single gene from a foreign source and iv. Enhanced plant detoxification.

Random Mating

Random mating occurs when each female gamete has an equal chance of being fertilized by any male gamete of the same plant or with any other plant of the population and, furthermore, there is an equal chance for seed production. It is not possible to achieve true random mating in plant breeding because selection is involved. Consequently, it is more realistic to describe the system of mating as random mating with selection. Whereas true random mating does not change gene frequencies, existing variability in the population or genetic correlation between close relatives, random mating with selection changes gene frequencies and the mean of the population, with little or no effect on homozygosity, population variance, or genetic correlation between close relatives in a large population.

Acid soils are found in India in about 93 million hectares ( Table 1) and they occur in the Himalayan region, the great Indo-Gangetic and Brahmaputra plains, peninsular plateau and uplands and the coastal plains including island eco-systems under varying environmental conditions of landscape, geology, climate and vegetation. Conditions which are conducive for the formation of acid soils, such as high rainfall coupled with high temperature encouraging intense weathering and loss of alkali and alkaline earth metals with a simultaneous accumulation of iron and aluminium hydroxy compounds or the formation of free acidic substances in the humid forest foot hill regions, exist in some region or other in almost all the states in India.  A soil with pH less than 7.0 is deemed as an acid soil (Soil Survey Staff,1951). However, for characterization and classification, acid soils may be defined as those having pH less than 5.5 in 1:1 water extract (Soil Survey Staff, 1999).

Horticulture deals with the art, science, business and technology of cultivation and management of horticultural plants. The word Horticulture is derived from two Latin words viz. ‘Hortus’ (means garden) and ‘Culture’ (means growing). Horticulture is an aesthetic science that deals with cultivation of fruit, vegetable, spice, plantation, medicinal, aromatic and flower crops. There is a vast therapeutic use of horticulture wherein gardening and aroma therapy are used to deal with new age maladies like depression and various addictions.

In ancient times, huge gardening spaces to grow large number of fruits, vegetables and flowers were available and these areas were demarcated with the help of high walls. This enclosed area was referred to as garden. This led to the term garden culture. The land area is decreasing due to industrialization and population growth, at the same time, there is a drastic increase in demand for horticultural produce. To meet the increased demand for horticultural produce and to cope up with the space constraints, multitier cropping systems, vertical gardening and other intensive cultivation practices are being resorted to. Hence, horticulture may also be described as the “Practice of growing and manipulating plants in a relatively intensive manner”.

Presently, fruits, vegetables, flowers and ornamentals are grown not only within the home premises, but also in large quantities on a commercial scale. In other words, many horticultural crops throughout the world are grown primarily as business enterprises. Thus, horticulture has two aspects in general i.e., the amateur and the professional. In addition, with the establishment of horticultural experiment stations as an integral part of colleges and universities, comparatively a large amount of scientific information on the behaviour and cultivation of horticultural plants and products is freely available. This information or literature, constitutes the science of horticulture, and the application of this scientific information constitutes the “Technology of Horticulture.” Thus, present day horticulture may be defined as the science and technology of production, processing and merchandising of fruits, vegetables, flowers and ornamentals where each crop has its own science and technology. Consequently, horticulture may appear differently to different people. To a teacher, professor, research scientist, extension official and landscape architect, it is an applied science and a profession, while to a commercial producer, wholesaler, a retailer of horticultural products, or to the manufacturers or seller of horticultural products, it is a business. It is also a fascinating hobby for connoisscur.

The narrow sense heritability estimates were high for days to first flowering, plant height at first flowering, number of leaves at first flowering, plant height at maturity, productive tillers per plant, boot leaf area, 100 grain weight, grain length and grain L/B ratio. These characters may be controlled by additive genetic variance. This indicated that the individual genotype can be evaluated readily from their phenotypic expression. Simple selection would more effective in the sets of materials exhibiting greater additive genetic variability and desirable mean performance. Thus, it merit selection in the next generation. On the other hand, the remaining traits may largely be controlled by non-additive genetic variance or the number of genes controlling these traits may be more, or these traits may largely be influenced by a large number of modifiers or might be largely influenced by environment. As the effects of the environmental variance were generally low, the observed low heritability for the above traits might be due other factors other than environment. These traits are hard to improve by selection. It necessitates progeny testing.

The relative magnitude of different gene effects and an understanding of the mode of inheritance of complex quantitative traits have a direct bearing on the method of hybridization and selection which should be adopted in a specific breeding programme. Useful biometrical methods have been developed by the Birmingham group of scientists, to analyse the genetic architecture in organisms, through the use of first and second degree statistics obtainable from the true breeding inbreds, their first generation crosses and the different types of segregating progenies (Mather, 1949; Hayman, 1958; Gamble, 1962; Mather and Jinks, 1971). Since then this method has been widely used in the genetic analysis of various crops.

Generation of new genetic variability through recombination breeding followed by appropriate selection procedure is one of the key factor for crop improvement. Gain in selection is restricted by correlated response of agronomically desirable as well as undesirable characters. There is a host of examples in various crop species where genes for desirable agronomic traits have been found to be closely linked with those governing undesirable characters (Murthy, 1971; Clegg et al., 1972). Such close linkages delay the realization of the full recombination potential in many crops. The biparental mating or the disruptive mating scheme, finds its importance in the improvement of autgamous speice,s because it increases the probabilities of obtaining useful recombinants as compared to selection without intermating (Hanson, 1959; Jensen, 1970).

In contrast to classical pedigree breeding, random mating population could produce large amounts of variability. This variability can be maintained in the population by the use of recurrent intermating, while the population is improved by selection. According to the standard breeding methodology in self-pollinated crops selection for quantitative characters are generally taken up in early segregating generations. For characters like yield, selection is continued till the material becomes homozygous. Such characters are controlled by large number of genes and a very large population has to be raised to make selection effective. Since most plant breeders could never grow the theoretically required size of population, the recombination is highly restricted. It is likely that many of the valuable genes may be practically lost in the process of advancing the material by continued selfing the generations. Andrus (1963) suggested crossing of selected sibs in early generation for reassembling the genes capable of functioning in a balanced polygenic system.