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Fruits and vegetables account for nearly 90% of total horticulture production in the country. India is the second largest producer of fruits and vegetables in the world and the leader in several horticultural crops namely Mango, Banana, Papaya, Cashewnut, Arecanut, Potato and Okra. However, the nature of horticultural crops being such that it’s not easy to make assessment of their production. These crops, especially vegetables are grown in small plots, fields or in the backyard of the houses; do not have single harvesting in most of the cases which makes their assessment difficult. Many horticultural crops have multiple pickings in a single season. Similarly many fruit trees are scattered, which do not count for assessment.

India has witnessed increase in horticulture production over the last few years. Significant progress has been made in area expansion resulting in higher production. Over the last decade, the area under horticulture grew by 2.6% per annum and annual production increased by 4.8%. During 2017-18, the production of horticulture crops was 311.71 Million Tonnes from an area of 25.43 Million Hectares. The production of vegetables has increased from 101.2 Million Tonnes to 184.40 Million Tonnes since 2004-05 to 2017-18 and production of fruits has increased from 50.9 Million Tonnes to 97.35 Million Tonnes since 2004-05 to 2017-18.

The world ‘‘Unfruitfulness’’ means a state or character of being unfruitful or barrenness. It is a vital constraint in so many fruit crops leading to a great loss to the farming community. In contrary, ‘Fruitfulness’ is the state where a fruit plant is not only having the ability of flowering and fruiting, but also carry on these fruits up to maturity. The inability of the plant to do so is known as ‘unfruitfulness’ or ‘barrenness’. Despite of profuse flowering, poor fruit retention in an orchard has been found owing to poor fruit setting at initial stage and subsequently abscission of the fruitlets. All the trees of an orchard do not bear flowers and fruits in the same extent or regularly and sometimes fail to bear flowers and fruits under similar conditions while other trees bears heavily. Such type of characteristics of trees may be attributed to unfruitfulness. Thus, all the problems affecting fruit retention upto final stage can be considered under unfruitfulness of a tree. Therefore, it is a very complex problem of an orchard and needs proper understanding for economical and effective management to maintain sustainable production of fruit crops.

CAUSES OF UNFRUITFULNESS

There are innumerable causes perceived behind unfruitfulness. Majorly, It may be due to poor root shoot ratio, lack of balance between vegetative and reproductive (fruiting) growth, heavy crop load which leads to restriction of fruit bud production and finally short of the crop in the following years.

Juvenility

Juvenility is referred to the phase of plant growth following germination from seed during which flowering does not occur and the bud meristem is not competent to respond to seasonal environmental inductive cues, and hence plant remains vegetative. The changes from juvenile to mature characteristics are well known as phase changes phenomenon. Plants are unable to initiate flowering after germination and have to undergo in a juvenile developmental phase. This transition period (phase) is a gradual and continuous process until the flowering takes place. The length of this phase varies considerably between different species. In annuals like Arabidopsis, the juvenile phase is typically very short, whereas in perennials like hybrid aspen, it is several years.

A plant is considered juvenile from the time it is at seedling stage until it is mature and capable of initiating flowering. Length of juvenile period in most of woody plants is still considered as a big problem. Indeed, it affects the plant breeding efficiency, plant propagation, and selection of new cultivars. In fact, juvenility is a complex phenomenon still not fully understood. Juvenility period extends from seed germination until the plant attains the ability to flower. Furthermore, all the stages namely seed germination, juvenile growth period and transition to the reproductive stage until fruitful inflorescence development are long and not always synchronous in the seedling population. It arrives at the age 30-40 years in Fagus sylvatica L., and at l0 years or even more in olives. Juvenile period is affected by both environmental and genetic factors. Attempts made in past to overcome juvenile period in most woody plants on the environmental level have shown very limited success.

Fertilizer is a substance of natural or synthetic origin, applied to soils or to plant tissues (usually leaves) for the supply of one or more nutrients essential to the plant. It is classified in two types, inorganic fertilizers and organic fertilizers. Both the fertilizers play major role to the crops if they are properly and appropriately applied. To obtain maximum benefits, it is important to apply fertilizers at an appropriate time, amount and in a precise manner. The method of fertilizer application should be selected appropriately taking into consideration the age and stage of crop plants, their root extensibility, type of orchard management, kind and amount of fertilizers to be applied. The fertilizers should be given over the area of crop plants, where their active roots are spread. In fruit trees, fertilizer should be given in restricted area i.e. in the surrounding area of about 1 to 1.5 m away from the trunk of the trees in active root zone.

When to apply the fertilizers?

Majority of the crops require nutrients at different stages like growth & development, flowering and fruit setting time. In fruit crops, stages like new flushes emergence, floral buds differentiation and fruit development require more nutrients. Time of application of fertilizers may also vary depending on types of fertilizers, need of the crops, soil and climate.

Irrigation is one facet of the inputs which need to be carefully managed so that profits are maximized. Irrigation plays a major role in any agriculture crop production. One should be aware of different types of irrigation adapted in orchards or crop cultivation to become a successful grower. Irrigation is very important component of crop cultivation as sufficient moisture must be maintained in the soil for obtaining the optimum growth and good quality yield. The aim of irrigating a plant should be to wet the entire root zone without allowing any wastage of water beyond the root zone. The irrigation systems have to be properly devised so that the water requirements of the trees are met at the minimum expenditure without any wastage of water. Irrigation practices can be improved if a range of important factors like crop type, crop water requirements, climatic conditions, soil type, water quality, method of irrigation are taken into account.

Crop type

The type of horticultural crops grown influences irrigation practices. Annual vegetable and melon crops have high water requirement, hence irrigation management is extremely critical to their productivity during their relatively short life span (10-20 weeks). Perennial fruit crops tend to require less water and management, although critical, is not generally as critical as for annual crops.

The high density planting (HDP) in fruit crops is one of the new concepts of increasing the productivity without affecting the quality of fruits. The concept of high density planting was pioneered in temperate fruits in Europe at the end of 1960, since then there is rise in establishment of commercial high density orchards throughout the world. Initially HDP was followed mostly in temperate fruits e.g., apple. HDP is defined as a method of planting wherein more numbers of plants are planted per unit area as compared to conventional planting density or it is a modern method of fruit cultivation involving planting of fruit trees densely, allowing small or dwarf trees with modified canopy for better light interception and distribution and ease of mechanised field operations. It is one of the important methods to achieve high productivity per unit area both in short duration and perennial fruit crops.

Now-a-days, new orchards of fruits are planted in this system with a view to produce higher fruit yield and increased profitably. In addition, there is also a need to feed the growing population and provide them nutritional security and land resources are shrinking simultaneously due to the industrialization, urbanization etc., hence it is required to develop the modern facilities to compete with the developed nation. The success of this technology in most of the fruit crops is dependent on the use of methods to control shoot growth so as to maximize light interception. The main aim of HDP is to obtain the twin prerequisites of productivity by maintaining a balance between vegetative and reproductive growth without sacrificing plant health and fruit quality.

The fruit trees are grown for optimum production of quality fruits that fulfill our requirement. Therefore, proper care and management of trees is mandatory to manipulate plant growth and plant environment. Training and pruning are important operations that provide not only the proper framework to the tree but also the favourable environment leading to desired plant growth and reduction in disease and pest attack.

Training

It is a physical manipulation technique that provides proper shape, size and direction to the plant in initial stage of growth. The techniques like tying, fastening, staking, supporting over a trellis or pergola in a certain fashion or pruning of some parts are are followed.

Objectives

• To improve physical appearance and usefulness of plant by providing appropriate shape and size to the plant and maintaining proper root-shoot balance.
• To facilitate easy cultural operations including canopy management, inter-cropping, plant protection and harvesting.
• To develop strong scaffold branches with better crotch angles in all directions that are capable of bearing heavy crops over the years without breakage of limbs.
• To provide adequate sunlight and air to the centre of the tree.

Layout of an orchard

Layout means the way by which something is arranged or laid out. The purpose of designing a layout for an rchard is to assign the actual position for trees/ plantations, roads, water channels, buildings etc. The layout should be planned very carefully and implemented properly to facilitate proper care and maintenance of an orchard. The plan should provide optimum number of trees per unit area as well as sufficient space to each of the tree for proper development and ease in various cultural operations of the orchard.

Materials required for layout

Measuring tape, rope, pegs, poles and planting board.

Based on agro-climatic conditions, the following system of planting are generally followed for planting of fruit trees:

1. Square
2. Rectangular

Plant Propagation is a technique through which multiplication or production of new individuals take place from selected propagules. The methods of propagation are broadly divided in two categories:

1. Sexual method
2. Asexual method

1. Sexual method of Propagation

In this method, plants are produced from seeds and such plants are called seedlings. Seed is considered as a dormant plant which develops into a complete plant if subjected to congenial environment.

Advantages

1. This is very simple, cheap and easy method of propagation.
2. Some species of fruits, ornamental annuals and vegetables which cannot be propagated by asexual means should be propagated by this method. e.g. papaya, marigold, tomato etc.
3. Hybrid seeds can be developed by this method.

A nursery is a place, where seedling, saplings, trees, shrubs, and other plant materials are grown and maintained until they are placed in a permanent place.

Advantages of Nursery

1. The area being small and compact, it is convenient and easy to grow large number of seedlings per unit area.
2. Management of favourable growing conditions becomes easy and feasible.
3. Easy management of pests and diseases in compact area.
4. Establishment of disease free and virus free scion bank.
5. Ensure optimum utilization of labour, water, nutrients and other inputs.
6. Ensure easy and cheap availability of plants.
7. Promotion of export through supply and processing of quality plant materials.

A seed (in some plants, referred to as a kernel) is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant. The formation of the seed completes the process of reproduction in seed plants (started with the development of flowers and pollination), with the embryo developed from the zygote and the seed coat from the integuments of the ovule. In broad sense, seed is a material which is used for planting or regeneration purpose. Seed technological point of view, seed may be sexually produced matured ovule consisting of an intact embryo, endosperm and or cotyledon with protective covering (seed coat). It also refers to propagating materials of healthy seedlings, tuber, bulbs, rhizome, roots, cuttings, sets, slips, all types of grafts and vegetatively propagating materials used for production purpose. Quality seed, therefore, can be defined as the seed which fulfills the minimum requirements of getentic and physical purity, seed germination and vigour freedom from weeds and other crop seeds and other relevant seed standards.

HORTICULTURAL CLASSIFICATION OF PLANTS

The Horticultural crops are majorly classified on the basis of its consumption and uses as fruits, vegetables, flowers, spices, medicinal, aromatic and plantation crops. Moreover, these crops have been further classified into various groups on the basis of their habitat, growth pattern, edapho-climatic requirements and uses. All branches of horticulture classified specifically as hereunder:

A Classification of fruits

1. Based on Climatic adaptability
   1. Tropical fruits: These fruit crops are grown in tropical climatic regions which are geographically located between the parallels of 23° 27' South (Tropic of Capricorn) and 23° 27' North (Tropic of the Cancer) of the equator. They are generally evergreen and very sensitive to cold. Eg. Mango, Pineapple, Banana, Papaya, Citrus, Sapota, Avocado etc.
   2. Sub-tropical fruits: Fruit crops are grown in between temperate and tropical climatic regions. They may be either deciduous or evergreen nature. Eg. Mango, guava, citrus, durian, jackfruit, bread fruit etc.

Horticulture has emerged as one of the potential agricultural enterprises in accelerating the growth of economy in India. It offers not only a wide range of options to the farmers for crop diversification, but also provides ample scope for sustaining large number of agro-industries which generate huge employment opportunities. Horticulture has been evolving in form of horticulture industry in our country owing to its significant role in nutritional security, poverty alleviation and employment generation. The production of fruits, vegetables and flowers has acquired much importance in recent times due to their increasing demand. India has a wide variety of climate and soil on which different horticultural crops such as fruits, vegetables, ornamentals, medicinal and aromatic plants, plantation crops and spices are cultivated successfully.

German Prof. Peter Laurenberg conceived first the word horticulture. The term “Horticulture” is known in written form first in seventeenth century in a book entitled “New World of Words” by Phillips.

Etymologically the word “Horticulture” is derived from two Latin words viz. ‘Hortus’ [garden or enclosure] and ‘Cultura’ [cultivation]. So, literally horticulture means ‘garden or enclosure culture’ or ‘cultivation of garden crops within protected enclosures’.

Garden: Garden is a broad term derived from the Latin word Gyrdan meaning “to enclose”.

DIVISIONS AND DEFINITION OF HORTICULTURE

Pomology: (pomum = fruits, logy = science) It is a branch of horticulture which deals with study or cultivation of fruit crops starting from raising of saplings and intercultural to harvesting operations. The ‘pomology’ term is derived from latin word pomum (means fruits) and greek word logy (means science).

1. Genus - Pythium (Type species - Pythium aphanidermatum)

‘Pythium’ is a large genus comprising of more than 200 species. Species of Pythium are either terrestrial or aquatic. They are found world wide and most of them are plant pathogens on many economically important cultivated crops, as well as wild plants. They are facultative saprophytes and can live saprophytically in the soil and plant debris for indefinite periods in the absence of suitable hosts. Pre-emergence and post-emergence damping off of seedlings of numerous angiospermic plants, root rot, rhizome rot and fruit rot are the most common diseases caused by species of Pythium.

Pythium debaryanum, Pythium aphanidermatum, Pythium myriotylum, Pythium indicum, Pythium vexans and Pythium graminicolum are some of the most important plant pathogens, that cause damping off, seed decay, soft rots and root rots of many economically important crops, such as chillies, eggplant, tobacco, tomato, castor, potato, ginger etc.

Life cycle of Pythium

The mycelium of the fungi consists of slender, hyaline, coenocytic hyphae. The hyphae grow both inter- and intra-cellularly. No haustoria are produced.

1. Ginger (Zingiber officinale)

‘Ginger’, which originated in Southeast Asia has a long history that goes back over 5000 years when the Indians and Ancient Chinese considered it as a tonic root for all ailments. At an early date it was exported to Ancient Rome from India and was used extensively by the Romans. Subsequently it was cultivated in several other countries for its medicinal value. Ginger is cultivated in most of the states of India. Kerala and Meghalaya are the major ginger growing states. India’s production of ginger constitutes about 50 per cent of the total world’s production.

Ginger is an erect, herbaceous , perennial, flowering plant, the rhizome of which is used as a spice. Ginger is an ancient spice and is a common ingredient in many Asian foods and is used in soups, curries, noodles, stews etc. It is widely used to flavor beverages, such as tea, coffee, lemonades, cocktails etc. In many places across the world ginger is used in sweets, alcoholic beverages, such as ginger beer and wine. Ginger has powerful anti-inflammatory properties. Further it has many other health related benefits, such as ability to help with arthritis, osteoarthritis, relieves nausea and pain, prevents cancer, improves respiratory conditions and reduces flatulence. It also boosts bone health, strengthens the immune system and increases appetite.

A ‘spice’ is a seed, fruit, root, bark, bulb, corm, rhizome or any other part of a plant primarily used for enhancing the taste, flavor or color of food. Some spices serve as preservative of food substances. Many spices have antimicrobial properties. Spices are sometimes used in medicines, religious rituals, cosmetics, perfumes etc. Spices are more commonly used in countries having warmer climates, especially in meat preparations. Many spices have substantial antioxidant property due to the presence of phenol compounds, particularly flavanoids.

India is the major producer of spices and contributes about 75 per cent of world’s spice production. Developing and under developed countries of the world supply about 55 per cent of spices to the global markets and the major markets in global spice trade are the United States of America, The European Union, Japan, Singapore, Saudi Arabia and Malaysia.

Objectives

1. To identify the morphological character of different spices and condiments.
2. To know the best variety of particular crop in that region.
3. To know the problems which are the main drawback of that region in the cultivation of spices and condiments.
4. To know the feedback of farmers.

General information of Institute

1. Name of Institute:
2. Address of the Institute:
3. Establishment year of the institute:
4. Director of the Institute:
5. Total area of the Institute:
6. Climatic condition of Institute:

Objectives

1. To know about value addition and its benefits.
2. To know the value added products of various spices and condiments.

Value addition: The maximum realization of the price of the product through processing, packaging and marketing.

Benefits of value added products over raw spices

1. Easy to carry
2. Long lasting flavours
3. More volume can be handled / per unit area
4. Easy to store, free from bacterial contamination.
5. Increases foreign exchange as they are used in food industry, preservatives and pharmaceutical industry.

Objectives

1. To know the methods of essential oil extraction of spices and condiments.
2. To know the various chemicals present in the essential oil of different spices and condiments.

Essential oil: Essential oils are the liquids that are isolated from plants when introduced to solvents. They are liquefied versions of the plants.

Extraction methods of essential oil

1. Steam Distillation
2. Solvent Extraction
   1. CO₂ Extraction
   2. Maceration
   3. Enfleurage
3. Water Distillation
4. Water and Steam Distillation

Objectives

1. To know the various steps involved in the processing of various spices and condiments.
2. To know the grade of some spices and condiments.

Processing: Perform a series of mechanical or chemical operations on (something) in order to change or preserve it.

Processing of some spices and condiments are given below

1. Black pepper

Processing involves the following steps:

1. The fresh berries are dipped in hot water for a minute which results in an attractive black colour and also reduces the drying time.
2. The berries are separated from the spikes and dried in the sun for 7-10 days.
3. When dried, the berries retain the characteristic wrinkled appearance of black pepper of commerce.

Objectives

1. To study the maturity indices of various spices and condiments.
2. To study the harvesting time and yield of various spices and condiments.

Maturity: A stage of attainment of final state of biological function beyond which growth and development ceases.

Maturity indices: An indication of appropriate stage of harvesting of the produce.

Harvesting: It is deliberate action to separate the plant product from its source of attachment.

Why harvesting at right stage for spices and condiments?

1. To avoid loss of flavour and volatile oils
2. Reduction in yield due to shattering
3. To get the higher yield
4. Recovery of more essential oil
5. Chances of attack of mycotoxigenic and storage pest

Objectives

1. To study the objectives and principles of training and pruning.
2. To study the methods of training and pruning.

Training: It refers to judicious removal of part to develop a proper shape of plant capable of bearing heavy crop load.

Objectives of Training

1. To admit more light and air to the centre of the tree to expose maximum leaf surface to the sun
2. To direct the growth of the tree so that various cultural operations such as spraying, ploughing, harvesting can be performed easily and at lower cost.
3. To protect the tree from sun burn and wind damage.
4. To secure a balanced distribution of fruit bearing parts of the tree.

Objectives

1. To study the weeds and its control.
2. To study the herbicides, their types, timing and methods of application.

Weed: A wild plant growing where it is not wanted and in competition with cultivated plants.

Or

Weed is such undesirable plant grown in association with crop which snatches major parts of nutrients, water, light, place and CO₂ available to the crop.

Due to tough competition crop suffers adversely and the production is reduced.

Objective

1. To know the different types of fertilizer application methods applied in spices and condiments.

Methods of fertilizer application: The different methods of fertilizer application are as follows:

a) Broadcasting

1. It refers to spreading fertilizers uniformly all over the field.
2. Suitable for crops with dense stand, the plant roots permeate the whole volume of the soil, large doses of fertilizers are applied and insoluble phosphatic fertilizers such as rock phosphate are used.

Broadcasting of fertilizers is of two types

1. Broadcasting at sowing or planting (Basal application): The main objectives of broadcasting the fertilizers at sowing time are to uniformly distribute the fertilizer over the entire field and to mix it with soil.

Objective

To know about the production practices used in spices and condiments.

1. Mulching: Mulch is a layer of material applied to the surface of soil.

Benefits of Mulching

1. Conservation of soil moisture
2. Improving fertility and health of the soil
3. Reducing weed growth
4. Enhancing the visual appeal of the area

Types of Mulching

1. Organic mulching: Organic mulches include bark nuggets, grass clippings, straw or salt marsh hay, compost and chopped leaves.
2. Inorganic mulching: Inorganic mulches include gravel, polythene and landscape fabric

Objectives

1. To know the layout methods.
2. To know the planting techniques of various spices and condiments.

Layout: Systematic arrangements of plants

Some spices and condiments just like clove, cardamom is perennial in nature. Being perennial in nature any mistake committed during initial year, on the part of planning, is hard to rectify. Hence, all the factors having bearing on growth, production and overall performance of the plant should be given top priority.

Systems of planting

1. Square system: In this system row to row distance and plant to plant distance is kept similar.

Objectives

1. To know about the seed treatment of spices and condiments.
2. To know the sowing method and time of spices and condiments.

Seed treatments or seed dressing: Seed treatment refers to the application of fungicide, insecticide, or a combination of both, to seeds so as to disinfect and disinfect them from seed-borne or soil-borne pathogenic organisms and storage insects. It also refers to the subjecting of seeds to solar energy exposure, immersion in conditioned water, etc. The seed treatment is done to achieve the following benefits.

Advantages of seed treatment

1. Protects germinating seeds and seedlings against soil and seed borne pathogens/insects.
2. Seed germination enhancement.
3. Early and uniform establishment and growth
4. Enhances nodulation in legume crop.
5. Better than soil and foliar application.
6. Uniform crop stand, even in adverse conditions (less/high moisture)

Objectives

1. To know the propagation and its methods.
2. To know the propagation methods of various spices and condiments.

Propagation of plants

The process of increasing plant numbers is called propagation

Or

Multiplication of plants is known as propagation

Plants are propagated either by

1. Sexual (Seed) or
2. Asexual (vegetative) methods.

Objective

1. To know the morphology of different spices and condiments.

Materials: The crop of spices and condiments available at Horticulture research farm

Method of observation: Identification of various spices and condiments plants by carefully observing the root, stem, leaves, inflorescence, flower, fruit and seeds of the plants.

General

1. Habitat: A habitat is an ecological or environmental area that is inhabited by a particular species of plant. The term typically refers to the zone in which the plant lives and where it can find food, shelter, protection and mates for reproduction It is the natural home of a plant. Each habitat has its own particular type of climate like:
   1. Tropical Spices: These are grown at 1800 m - 3500 m height from ground level eg. clove, nutmeg, cinnamon, konkam, galangal, small cardamom, vanilla, black pepper, ginger, turmeric.
   2. Subtropical Spices: These are grown at 300 m - 900 m height from ground level eg. cumin, dill, fennel, coriander, fenugreek, onion, garlic
   3. Temperate Spices: These are grown at 900 m - 1800 m height from ground level eg. saffron, asafetida, caraway seed, celery seed, savoy, caper, balm, origanum, calamus, thyme etc.

Objective

To study the salient features of important varieties of spices and condiments.

1. Cardamom

Table 3.1: Released/Recommended Cardamom Selections- Estimated Yield and Source of Variability.

2. Black pepper

Table 3.2: Improved varieties of black pepper and their character

Objectives

1. To know the botanical and other names of spices and condiments.
2. To identify the family, plant habit and plant part used of spices and condiments.

Objective

1. To classify the various spices and condiments.

Types of classification: spices and condiments are classified on the following basis:

1. Classification on the basis of economic importance
2. Classification on the basis of parts used
3. Classification on the basis of climatic requirements
4. Classification on the basis of life cycle
5. Classification on the basis of taxonomy
6. Botanical classification

Essential oil is a concentrated hydrophobic oily fragrance liquid extracted from plants, containing easily evapourated chemical compounds at room temperature. Essential oils are extracted from the different plant parts including the flowers, leaves, stem, bark, and roots, and they are extracted from different techniques. The most preferable method of extraction is hydro distillation which is easy to use and cheap. Essential oils are used in every field of life, used in aromatherapy, and act as antifungal, antioxidant, anxiety, pain relievers, and depression.

Anthocyanins are members of the flavonoid group of phytochemicals, a group predominant in teas, honey, wines, fruits, vegetables, nuts, olive oil, cocoa and cereals. The primary players in this group include the anthocyanins (eg, cyanidin, pelargonidin, petunidin), flavonols (quercetin, kaempferol), flavones (luteolin, apigenin), flavanones (myricetin, naringin, hesperetin, naringenin), flavan-3-ols (catechin, epicatechin, gallocatechin), and although sometimes classified separately, the isoflavones (genistein, daidzein) (Skibola and Smith, 2000).

Phenolic compounds constitute a major class of plant secondary metabolites that are widely distributed in the Plant Kingdom. Plant phenolics are biosynthesized through the shikimate/phenylpropanoid pathway leading to different compound classes. They may occur in their natural sources in free forms, as glycosylated or acylated derivatives, and as oligomeric and polymerized structures, such as hydrolyzable and condensed tannins, phlorotannins or lignins. They may also be found linked to plant matrix components such as cell walls, carbohydrates or proteins. It should be indicated that although the terms “plant phenolics” and “polyphenols” are indistinguishably used by some authors, they are not synonymous.

Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. Alkaloids showed quite diverse medicinal properties (Rates, 2001). Many of them possess local anesthetic properties, but their practical use is limited for clinical purposes (Hesse, 2002). Morphine is one of the most known alkaloids isolated from Papaver somniferum (opium poppy), which had been used and still is for medical purposes. This alkaloid is a powerful narcotic which is used for the relief of pain, but its usefulness is limited because of its addictive properties.

The following plants have been worked out in the laboratory of Prof. N. Raaman: Cynodon dactylon, Artemisia pallens, Leptadenia reticulata, Clausena dentata, Tylophora indica, Aristolochia bracteolata, A. indica, Cissus quadrangularis, Hypericum mysorense. and Solanum trilobatum. Out of some of the data of these plants have been included in the previous chapters. In this chapter, compound isolation (CD1) from Clausena dentata (worked by Dr. R. Kamaraj) and characterization of the compound are given in detail.

Phytochemicals are the individual chemicals from which the plants are made. Phytochemical is simply a word that means plant chemicals. Plants have the ability to synthesize mixtures of structurally diverse bioactive compounds with multiple and mutually potential therapeutic effects. The plants have the capacity of manufacturing the secondary products. Phytochemicals with antioxidant properties tend to be brightly colored because they contain chromophores, ie, a series of alternating single-bonded and double-bonded carbons. Isoprene is often the building block of such units. The darkest green vegetables contain the most chlorophyll, and vegetables with the most chlorophyll require the most antioxidants.

After isolation and purification of the compound, it has to be identified. It is necessary to find out the class of the compound first and then to find out the specific compound within the class. The class of compound is usually determined from the colour tests, solubility, Rf properties and UV spectral characteristics of the compound. Further identification within the class depends on measuring physical properties and spectral measurements and then comparing these data with those in the literature.

For qualitative and quantitative analysis of phytochemicals, chromatography can be used. Gas chromatography is a powerful means of performing qualitative and quantitative measurements of complex mixtures of volatile substances, which are vaporizable without decomposition.Gas Chromatography-Mass Spectrometry (GCMS) system is a widely used instrument for qualitative and quantitative analysis of solid, liquid, and gaseous samples. Samples are converted into gaseous ions and then separated on the basis of their mass-tocharge ratio. 

All separation procedures depend mainly on some physical characteristics of the compounds. It is relatively easy to separate compounds that have significantly different physical characteristics by simple techniques such as solvent extraction. If the various compounds are similar to each other in their molecular size, any slight difference in any one of their physical properties is exploited to achieve separation. 

The different qualitative chemical tests can be performed for establishing profile of given extract for its chemical composition. The following tests may be performed on extracts to detect various phytoconstituents present in them.

Extraction is a process whereby the desired constituents of a plant are removed using a solvent. The primary ways for extraction of organic molecules of interest to biologists and medical investigators involve breaking open the cells. Cell rupturing is carried out in a variety of ways. The method used depends on the type of tissue used. For plant cells grown in cell suspension culture or for plant callus tissue, a French press or a sonicator can be used to break open the cell.

Phytochemicals from various parts of a plant or tree such as the leaves, the flowers, the seeds, the barks, the roots and the shrubs can be isolated. Once one comes in from collecting plants in the field, it is good idea to freeze them immediately in a freezer at – 20°C or a commercial freezer held at – 80°C (Kaufman et al., 1999). According to Harborne (1984, 1998), fresh plant tissues should be used for phytochemical analysis and the material should be plunged into boiling alcohol within minutes of its collection. Alternatively, plants may be dried before extraction.

Dietary supplements from plant sources are sometimes referred to as phytopharmaceuticals. They are produced from fresh, dried or otherwise preserved plants or parts of plants. The active ingredients are usually not completely isolated but rather are obtained along with other naturally occurring components of the plant. These other components are often believed to influence the efficacy of the active ingredient. Sometimes the active ingredients are concentrated, and undesirable substances such as chlorophyll, tannins, or resins, are removed.

Plants are used as medicine since time immemorial. One of the area of Ethnobotany, Ethnopharmacology is considered as the scientific evaluation of traditional medicinal plants (Cotton, 1996). Cox (1994) has suggested that the ethno-directed sampling is most likely to succeed in identifying drugs used in the treatment of gastrointestinal, inflammatory and dermatological complaints. The Plant kingdom is a virtual goldmine of potential drug targets and other active molecules awaiting to be discovered. It has been estimated that only 10 - 15 per cent of the 7,50,000 existing species of higher plants have been surveyed for biologically active compounds.

About 25% of worldís total food production is lost due to insects, bacteria and rodents after harvesting.

Indiaís exports of Processed Food was Rs. 31563.43 Crores in 2014-15, which includes products like Mango pulp (Rs. 841.39 Crores), Dried and Preserved vegetable (Rs. 847.11 Crores), Other Processed Fruit and Vegetable (Rs. 2,569.93 Crores), Pulses (Rs. 1,209.51 Crores), Groundnuts (Rs. 4,675.35 Crores), Guargum (Rs. 9,480.00 Crores), Jaggery and Confectionary (Rs. 1,161.81 Crores), Cocoa Products (Rs. 848.62 Crores), Cereal preparations (Rs. 3,038.79 Crores), Alcoholic and Nonalcoholic beverages (Rs. 2,231.58 Crores) and Miscellaneous preparations (Rs. 2,437.77 Crores).

Medicinal plants are non-food non-plantation crops.

These are rich in secondary metabolites viz. alkaloids, glycosides, coumarins, flavonoides and steroids, etc.

Union government of India has started a project on 'Traditional Knowledge Digital Library' under which it is documenting all Ayurvedic formulations in a digital form to avert patent threats from companies in the developed world

Spices: It is defined as vegetable products (non-leafy parts) or mixture thereof, used for flavouring, seasoning and imparting aroma in food. It may be whole form or in ground form e.g. Pepper, Cardamom, Clove, Cinnamon, etc.