eChapters

1. Microscope

The microscope is a precious instrument. There are many small objects or details of objects which cannot be seen by the unaided human eye.
 
A microscope (from Greek: mikrós, means “small” and skopeîn, means “to look”) is an instrument used to see objects that are too small for the naked eye.  In another word microscope is an optical instrument that uses a lens or a combination of lenses to produce magnified images of small objects, especially of objects too small to be seen by the unaided eye.

Tissue culture consists of growing plants cells as relatively on organized masses of cells on an agar medium (callus culture) or as a suspension of free cells and small cell masses in a liquid medium (suspension culture). In other words, In plant cell culture, plant tissues and organs are developed in vitro on artificial media, under aseptic and controlled environment. The procedure depends mainly on the concept of totipotentiality of plant cells (Haberlandt, 1902) which refers to the ability of a single cell to express the full genome by cell division.

Newer technologies involve fermentation by specific strains of lactic acid bacteria which bring specific fermentation under controlled conditions to a specific fermented product with enhanced organoleptic, nutritional and therapeutic qualities. Today health is of primary concern. It is important to have nutritionally balanced food with good bacteria. For this, probiotic foods top the list. The functional food concept was initially developed in Japan in 1990‘s as there were many side effects of allopathic medicines. A regulatory system has been initiated by the ministry of health and welfare to approve certain foods to improve health. These are now recognized as Foods for specialized health use (FOSHU). According to American dietic association (ADA) these foods are potential healthful food or food ingredients that may provide health benefits beyond the traditional nutrients. Probiotics are beneficial microorganisms. Probiotic foods as yogurt and sauerkraut are very well known. Fermentation increases the nutrient content and taste with the shelf life.

There are potential beneficial medicinal uses of probiotics for which research is limited and only preliminary results are available. Recent research on the molecular biology and genomics of Lactobacillus has focused on the interaction with the immune system, anti-cancer potential, and potential as a biotherapeutic agent in case of antibiotic-associated diarrhoea, traveller‘s diarrhoea, pediatric diarrhoea, inflammatory bowel diseases and irritable bowel syndrome (Ljungh et al., 2009). Studies of some probiotics tested in vitro on human epithelial cell lines have shown that they could block the adhesion of shiga toxin producing E. coli (Sherman et al., 2005). These are claimed to be health promoting and/ or disease preventing beyond the basic function of supplying nutrients. Probiotic foods are emerging as an important category of food supplements. Earlier workers have shown the inhibition of diarrhea caused by E.coli using probiotic lactic acid bacteria and yeast (Yan and Polk, 2006). Ratledge et al. (2002) have studied the biochemistry and molecular biology of lipid accumulation in oleaginous microorganisms.

LAB constitutes a group of gram positive bacteria. They are nonsporulating, nonrespiring but aerotolerant cocci or rods, which produce lactic acid as one of the main fermentation products of carbohydrates, they do not have cytochromes. They belong to the phylum Firmicuttes, class Bacilli and order Lactobacillaceae. The group includes several genera such as Lactobacillus, Lactococcus, Bifidobacterium, Pediococcus, Enterobacter, Corynebacterium, Streptococcus, Leuconostoc etc.

4a. Intestinal Disorders
 
History of health claims
 
According to Bottazzi (1983) it was in 76 BC that the Roman historian Plinius recommended the use of fermented milk for treating gastroenteritis. Metchnikoff claimed that the intake of fermented milk containing Lactobacilli reduces the toxin producing bacteria, thereby increasing the longetivity of the host (Metchnikoff, 1908). Tissier (1905) showed that there was an increase in the Bifidobacteria in breast fed-infants, thus claiming that the administration of Bifidobacteria to infants suffering from diarrhea was very beneficial as they supersede the putrefactive bacteria that causes the disease. Intestinal beneficial microfloras are responsible to resist the disease (Bohnhoff et al., 1954).

The lack of mechanistic understanding of probiotic activity is a major drawback for the prediction of safety of probiotic intervention. The complex gut-associated microbial ecosystem and nutritionally related factors are the most important environmental triggers for the development and modification of chronic degenerative diseases including immune and metabolic pathologies. In fact, the interaction between the gut microbial ecosystem and the host is considered to be a critical factor in overall health or disease. Whether probiotics will exert protective, harmful, immune-stimulating or immune-suppressing effects on a host is dependent on the interaction between the microbial signals, the genetic make-up of the host and the effects by the environment. Many studies have revealed that certain probiotic bacteria stimulate immune cell proliferation and activity as evidenced by the production of cytokines and antibodies, thereby enhancing the effectiveness of the immune response against pathogens. Ng et al. (2009)

Probiotic Fermented food products
 
An individual requires adequate nutrients like proteins, carbohydrates, vitamins, and minerals to maintain diet. There has been an explosion of the consumer interest in the role of enhancing the health by some specific foods or physiologically active food components, so called functional foods (Hasler, 1998). The concept of functional foods evolved in the year 1990 in Japan.

Antibiotic Resistance and Gene transfer
 
It is important that probiotic strains should be assessed for their phenotypical antibiotic resistance and potential to transfer resistance gene as otherwise they cannot be used in food (BgVV, 2000; Vankerckhoven et al., 2008). It is vital to do research on characterization of acquired resistance mechanisms and transferability of resistance genes and on methods for determining transferability.

Probiotics are measured in colony forming units (cfu). CFUs are generally measured in the millions or billions per serving. Probiotics are most commonly beneficial bacteria, but can also be friendly fungal or other organisms, that are typically freeze dried to stabilize them in an inert state during storage and production. Then their continued stability and viability, as measured by CFU counts when cultured, is dependent on limiting their exposure to stimulating environmental conditions such as temperature and moisture. Besides refrigeration, this protection can be done by packaging in glass or by adding freshness packets that helps to absorb and reduce moisture in the package.

What new research is needed, what trials and how will the ultimate consumer and Industry benefit?
 
In Brazil, the sales of functional foods amounts to US $ 500 million per year representing about 1% of the total sale of the Brazilian food processing industry. According to a report the interests are mainly for dairy products, nutraceuticals and soy-based products. ABIA forecasts a substantial growth of 4.5-5% for this segment of the market (Stanton et al., 2001). In order to exert the health benefits beyond inherent basic nutrition, it is necessary that the activity of the probiotic culture should be maintained at very high levels during the shelf life of the product.

In spite of the problems with dosage and viability of probiotic strains, a lot more work is required for industry standardization and safety issues. However, it is noted that probiotics have considerable potential against many pathogenic and other diseases. A wide range of clinical trials are still needed to standardize and optimize the conditions. Ongoing basic research will continue to identify and characterize existing strains of probiotics, identifying strain-specific outcomes, determine optimal doses needed for certain results and assess their stability through processing and digestion.

Today it has been understood that yeasts have great potentials as novel probiotics (Nayak, 2011). They have been found to be safe for human consumption in traditional fermented foods (Jakobsen and Narvhus 1996). Yeasts have a great physiological importance inside the gastrointestinal (GI) tract (Czerucka et al., 2007; Gatesoupe, 2007). Jespersen (2003) has mentioned the role of consuming fermented foods and the health benefits attributed with it.Yeasts are known for prevention of table olive (Arroyo lopez et al., 2012). Bonatsau et al. (2015) have shown multi-functional property of yeast as starters.

The shift from vegetative to reproductive phase in plants is the result of multiple gene cascades in response to photoperiodic and temperature dependent pathways, gibberellic acid pathway, vernalization pathway and autonomous pathway. The environmental cues are initially detected in the leaves and the mRNA of the flowering signal integrator FT gene, moving to the shoot apical meristem, acts as a long-distance signal for floral meristem identity. At SAM, FT-FD protein complex, based on signals from above said pathways in association with the signals from age-dependent and miRNA pathways, leads to the activation of master regulator gene of flowering AP1. The activation of genes involved in ABCDE model of floral organ differentiation, based on the directions of various cadastral genes lead to the development of floral organs. Thus, the sequential action of floral meristem identity genes, floral organ developmental genes, floral meristem size and organ number genes, floral organ pattern genes and cadastral genes leads to the flower development. This chapter sums up the gene interactions happening in leaf and SAM, leading to the development of a complete flower.

Endophytic Microorganisms

Endophytes (‘endo’, inside; ‘phyte’, plant) include microorganisms that thrive inside the plant tissues without any obvious adverse effects on the host, and they include mainly bacteria and fungi (Hallmann et al., 1997; Bacon et al., 2002; Hardoim, 2015). Endophytic microorganisms share an intimate association with the host adding essential and functional capabilities. Therefore, plant may be considered as a superorganism composed of an amalgam of both selected symbiont microbiota and host cells (Hardoim, 2015) with the new concept of holobiome, i.e., plant together with the associated microorganisms collectively governing the plant activities (Hardoim et al., 2015; Vandenkoornhuys et al., 2015).

The scientific community working in the field of crop protection is experiencing an increasing academic and industrial interest in the discovery and development of new bio-insecticides as environmentally friendly pest control tools to be integrated, in combination or rotation, with chemicals in pest management programmes. In this context, Entomopathogenic nematodes (EPNs) as a bio-control agent have proven successful and are now commercially mass produced in six of the seven continents to treat pest problem in agriculture, horticulture and forest crops. They actively search for the host, including those in cryptic habitat stages of insect pests in soil environment. They can be considered as good candidates for integrated pest management in ustainable agriculture due to plants and mammals which are not adversely affected and have ease of mass production. We present a general overview on the current state of knowledge of EPN and their mutualistically associated bacteria and their utilization as biological control agent against insect pests in world and India are briefly presented in this chapter.

“Standards are to Industry as Culture is to Society” said Shri C. Rajagopalachari, the first Governor General of India. Shri C. Rajagopalachari was inaugurating a conference on Standardization and Quality Control in February 1948. The great statesman has beautifully summed up the importance of standardization.

The basic principles on which procedures and practices are based had their origin in the United Kingdom, where the first national standardization movement started as early as 1901. Thereafter, procedures have been continuously developed, modified and improved till considerable similarity is achieved.

Every research in agriculture aims at developing a promising new technology or refines an age old technology that can help addressing the improvement in crop yield. This is a worldwide scenario to meet up with the food needs of the growing population and reducing agricultural land resources. Many traditions in the world are associated with vast knowledge of cultivating the food crops, vegetables, fruits etc using selected methods that are modified based on the needs, climatic conditions and the resources available in the place of settlements. Soil based agriculture is the most popular method of growing plants since soil is considered as the main source of nutrients and water required for the healthy growth of crops. Generally it includes 3 major steps, ploughing, sowing and harvesting.

Labour is one of the biggest input costs for vegetable growers. Vegetable farming is labor intensive and time consuming. Frequently, it is associated with low yield and poor quality production. The constraints are high labor requirements for land clearing, ploughing, bed forming, mulch laying, seeding, transplanting, harvesting and transporting. Mechanization is interjection of improved tools, implements, machines and other equipments between man and materials (soil, water, environment, seed, fertilizer, pesticides, growth regulators, irrigation water, agricultural produce and by-products such as fruits, vegetables, and seeds, etc.)

The vegetables and fruits are largely consumed fresh and day by day, their market demand is increasing due to nutritious quality. However, market supply is not sufficient to meet public demand throughout the year as production is inadequate because crop production has not increased substantially in recent years due to climatic changes. Another important reason for low production is the economic losses incurred due to damages of insect pests and plant diseases.

Since ancient times, reduction in pest and disease incidence is sought by spraying of pesticides including conventional preparations such as tobacco decoction, Bordeaux mixture, neem leaf extract etc. During the green revolution years, the synthetic pesticides were greatly recommended for pest and disease control and thereby increasing crop yields many-fold. Having experienced the spectacular improvement in both yield and quality of marketable produce, farmers were solely dependent on synthetics and ultimately abandoned other control measures.

Pesticides are an undeniable part of modern life, used to protect everything from flower gardens to agricultural crops from specific pests. Pesticides have contributed significantly to improving quality of life and safeguarding the environment. Some 20 to 40 percent of the world’s potential crop production is already lost annually because of the effects of weeds, pests and diseases (according to the FAO reports) (www.CropLifeAmerica.mht). In addition to increasing crop yields, crop protection products used in stored products can also prolong the viable life of products, prevent huge post-harvest losses from pests and diseases and protect food safety for eating.

Soybean, a source of 40 per cent good quality protein, 20 per cent oil and other nutrients has great potential in meeting nutritional requirements and extending health benefits through soy based food products to Indian population. Soy foods are nutritious, economical and good for health. Regular food use of about 10 per cent processed soybean flour with cereal flours or 25-30 g properly processed soybean per day in a diet entitles the consumer to derive maximum nutritional and health benefits at a relatively low-price. Soy food products like fullfatsoyflour, soy-based bakery products and dairy analogs (soy milk, soy paneer (tofu), curd (dahi), soyshrikhand, soy amrakhand), being the products of acceptable type to Indian population, have good scope. Different organizations have given input in R&D work on soybean processing. SPU Centre at ICAR-CIAE, Bhopal has been involved in development of number of soybased food products, technology and equipment for preparation of those. To make available the properly processed soy food products to our population, the centre is actively engaged in capacity building of upcoming entrepreneurs and entreprise development for soybean processing for food uses. Around 500 cottage scale soy food enterprises have been established in different states of the country.

Centuries before Greece and Rome were discovered, sailing ships carried Indian spices, perfumes and textiles to Mesopotamia, Arabia and Egypt. It was the lure of these that brought many seafarers to the shores of India. Emperors, kings, senators and the aristocracy transformed spices into the mostly highly prized commodities of ancient trade routes The story of Indian Spices is more than 7000 years old. By the 1400s, when navigational equipment had improved to the point that long-haul sailing became possible, European rulers set out to change the balance of world trade by funding spice-hunting missions of their own. Christopher Columbus who, in searching for a quick route to India, reached the Americas. Vasco de Gama was the first to surround Africa, and with a crew led by Ferdinand Magellan, fully circumnavigated the globe.

Spices play important roles in daily life and India is a rich repository of spices. Various biotechnological approaches like micropropagation, somaclonal variation, in vitro conservation, synseed technology, protoplast fusion, production of flavor and coloring components, and development of novel transgenics have great significance in conservation, utilization and increasing the production and productivity of spices. Protocols for micropropagation and production of disease free planting materials are available for many spices. Efficient plant regeneration protocols are also available for exploiting somaclonal variation ,where the available natural variability is relatively low. Technologies for isolation and culture of protoplasts were reported in a few spices. Development of transgenics for disease resistance is gaining momentum. Synseed and Micro-rhizome technology are also available for many spices for safe propagation, conservation, movement, and exchange of germplasm. In vitro and cryo preservation technologies for conservation of spices germplasm are available for many spices.

Mango (Mangifera indica L.) is one of the most important tropical fruits of the world and is commonly known as the ‘King of fruits’ for its high quality fruits which are very popular among the Indians (Sharma et al., 2008). It is the oldest and extensively cultivated fruit crop in India having high socio-economic significance. India is the home of more than 1000 mango varieties, which originated in the Indo-Burma region (Mukherjee, 1958). India is the largest producer of mango, grown in about 2.3 million hectares with an annual production of 15.02 million tones. However, its productivity is only 6.5 tones per ha against 30 tones per ha in Israel (Bijay Jumar, 2010). Improvement of productivity in mango continues to be the foremost issue in mango production (Sauco, 1993). Of late, all the mango importing countries are considering the India as a source of quality mangoes due to its varietal wealth and availability. Hence, it is imperative to improve the productivity and quality of Indian mangoes to meet the global need (Balamohan et al., 2014).

The word Cymbidium has been derived from a Greek word ‘Kumbos’ meaning ‘hole or cavity’ referring to the structure of the base of the lip. The genus consists of 44 known evergreen species in the family Orchidaceae, subfamily Vandoideae, tribe Cymbidieae and sub-tribe Cryptopodiinae. It is distributed from northwestern India to China, Japan, south through the Malay Archipelago to the north and east Australia. (DuPuy and Cribb, 1988). Cymbidiums have been for over hundred years one of the most famous orchids in commerce.

The orchids are commercially important group of flowering plants and their flowers are affluent in uniqueness in their shape, size and colour, exquisitely attractive, remain fresh condition for long period of time in comparison to other flowers. Orchidaceae is the second largest family among floriculture; about 25000 to 35000 species of orchids have been reported over the world (Rampal and Nagrare, 2006). India accounts for nearly 7 per cent of world’s orchids genetic diversity contributed 1300 species under 184 genera (Arora, 1983; Rampal and Nagrare, 2006) and 1150 species belonging to 164 genera (Satish Kumar, 1994) of which about 800 species are found in the North Eastern region of the country (Nagaraju et al., 2006) and many more are discovered year after year because of the prevailing congenial climatic conditions, diverse terrain and altitudinal variations, which provide suitable habitat for orchids.

Methylene-cyclo-propyl-glycine (MCPG), is a cyclopropyl derivative, grouped into the amino acids that have been isolated from the higher plants (Fowden, 1960). MCPG was identified to be closely related to two other cyclopropyl derivatives (Fig. 1), 1-aminocyclopropane – 1 – carboxylic acid from Vacciniumvitis-idaea and perry pears (Vahatalo and Viertanen, 1957; Burroughs, 1957) and â- methylenecyclopropyl alanine (MCPA or Hypoglycin A) from Blighia sapida (Hassall and Rayle, 1955; Anderson et al., 1958; Ellington, Hassall and Plimmer, 1958).

Mango (Mangifera indica L), the king of fruits, is cultivated throughout a wide range of frost-free climates (Litz 1998). It is commercially the most important fruit crop of India, accounting for more than 54% of the total mango production worldwide. The fruit of mango (Mangifera indica L.) is exceptional for its juicy, succulent, thick fruit pulp and nutrient abundance in terms of wide range of amino acids, sugars, organic acids, minerals including Ca, P, Fe, and K and vitamins. Out of several diseases which attack mango crop, mango malformation disease is a serious threat to its cultivation since it causes gross deformation of the vegetative and floral tissues (Ploetz et al., 2002; Kumar et al., 2011). Floral malformation is a major problem in mango, rendering mango cultivation unproductive in northern India and other regions of the world (Pandey et al., 1977; Ram, 1991).

Tomato (Solanum lycopersicum L.) is one of the most important vegetable crops cultivated in the world. It is used as raw in salads and also used as cooked vegetable in the preparation of curries. Processed items such as tomato puree, ketchup, pickle, chutney, whole peeled tomatoes and tomato powder are also consumed considerably. It is a rich source of Vitamins A & C. Lycopene and other flavonoids in tomato serve as good source of antioxidants. Tomato occupies 5 million hectares with a productivity of 34t/ha. in the world. In India it is cultivated in an area of 0.88 million hectares with productivity of 21 t/ha.

Mango occupies a pre-eminent place amongst the fruit crops grown in India and is acknowledged as the ‘King of Fruits’. Mango is the pride of the garden and one of the choicest fruits known to mankind. Mango possesses unique nutritional and medicinal qualities apart from being a rich source of vitamins A and C. Young and unripe fruits are utilized for culinary purposes, preparing pickles, chutneys because of their acidic taste as well as for extraction of tannin and other astringent products. Ripe fruits are a delicacy for the table and are utilized in preparing squash, juices, nectar, jam, cereal flakes, custard powder, baby food, mango leather and toffee. Canned mango slices and pulp are indeed very popular. The inside kernel of the stone being rich in carbohydrates, calcium and fat, can be used as a source of food for certain industrial purposes.

Citrus is the world’s leading tree fruit crop, comprising of mandarins, sweet oranges, grape fruit, limes and lemons. It is one of the most important fruit crops grown under varying agroclimatic conditions in India except in the high hilly temperature regions. Mandarin orange (Citrus reticulata) is the most important commercial citrus in India followed by sweet oranges and acid limes. Citrus fruits are not only delicious and refreshing but also they provide vitamins, minerals and other substances. Different species of Citrus have different chemical composition. In sweet oranges, principal constituents of edible portions are sugars (glucose + sucrose) and acids (primarily citric acid and a little of malic acid), the fruits of acid groups contain primarily acids in fruit juice. Rind of citrus fruits is rich in pectin and contains essential oils and glucosides (hesperidin, naringin). Citrus fruits are a good source of vitamin C (ascorbic acid - 25 to 85 mg/100 ml juice), besides vitamin B, A and D. World-wide demand of orange is as fresh fruits, but orange marmalade is an important product and is one of the main uses of sour and sweet oranges. Grape fruit and mandarins are also taken as fresh fruits. Citrus fruit can be utilized in a number of other ways as salads, juices, squashes, cocktails, syrup, concentrates and pickles. Peel of thick-rinded fruits can also be made to delicious candy. Lemon is used in many culinary purposes. Grape fruit is utilized in preparation of wines and brandies and also for flavour and in perfumery.

Tomato, the ‘Apple of Love’ or ‘Golden Apple’ is one of the most popular, widely grown and highly praised vegetable in the world. In India, commonly referred as ‘Poor Man’s Orange’, has wider coverage in comparison to other vegetables. Tomato universally treated as ‘Protective Food’, is eaten raw or cooked or in processed form (soup, juice, ketchup, puree, paste and powder, green tomato - pickles and preserves) or it supplies vitamin C and adds variety of colours and flavours to food. It is a very good source of income to small and marginal farmers and contributes to nutrition of consumers. Tomato seed contains 24% oil used as salad oil and in manufacture of margarine. By virtue of its many attributes, it is considered as a favourite crop for research in physiology and cytogenetics, all over the world. Tomato is also rich in medicinal value. The pulp and juice are digestible, mild aperient, a promoter of gastric secretion and blood purifier. Tomato, a primary source of lycopene, showed significant association with low prostate cancer risk and cancers of digestive tract. It is one of the best vegetables which keeps our stomach and intestine in good condition. Tomato juice has become an exceedingly popular appetizer and beverage.

Onion is one of the most important commercial vegetable crops grown all over India. Onions are bulbous, biennial, herbaceous and are typically grown as annual, which give off a distinctive and pungent odour when the tissues are crushed. Characteristic pungency and flavour in onion are due to a volatile sulphur compound, allyl-propyl disulphide. This organo sulphur compound has potential for anticarcinogenic secondary metabolites. Pungency varies with cultivar, growing condition, stage of maturity and storage conditions.

It is such a unique vegetable, used throughout the year in the form of salad or condiment or for cooking with other vegetables. Onions are used for flavour, aroma and taste in preparation of vegetables and used in the form of dehydrated, freezing, canning and pickling. Onion salt is prepared by dehydration and used in flavouring.

Coconut is the most important palm of the wet tropics as a  major source of vegetable oil which also provides food, health drink, medicine, shelter, fuel, timber and fibre.  Because of its versatile nature, it is eulogised as ’Tree of Heaven’, ‘Tree of Life’, Kalpavriksha, Tree of Abundance, Natures supermarket and king of palms.  Oil is extracted from dried endosperm  which is called ‘copra’. The unopened flowering spathe, on tapping process, yields a delicious sap (Coconut Inflorescence Sap) rich in sugars and vitamin B, is called toddy from which sugar syrup and many products can be extracted.  An intoxicating drink called arrack can be prepared by distilling fermented toddy. The hard endocarps of fruits supply fuel and charcoal and mesocarp yields fibre for coir industry. Leaves are used for thatching houses.  Young unopened leaves are used to decorate festive places.

Black pepper is popularly known as ‘King of spices’, it is the dried berry of the pepper vine, so important in the International Trade Market. The crop has its origin in the tropical rain forests of Western Ghats of India.  Kerala is the leading State in the production of black pepper with the ubiquitous presence of this crop in coconut, arecanut and coffee plantations. Chief pepper producing countries are Indonesia, Brazil, Malaysia, Cambodia, Sri Lanka and Vietnam.

Even since, the man adopted plant cultivation; he attempted various methods of propagation. In ancient time, the only source of plant multiplication was by seeds. Hence, techniques for higher seed germination, improved seed vigour were developed by giving pre-treatment. However, as the knowledge advanced and demands for having true to type plants was realized to man shifted his cultivation practices for some plants from seed to vegetative propagation such as cutting, layering and grafting. The use of cuttings, corm, bulbs, tubers  for multiplication were known to ancient peoples as mentioned in old literature. This method also gave an edge to conserve the genetic gain once developed in a cultivar, since all vegetatively multiplied plants will have some genome and will produce true to type plants. Thus, the development of vegetative propagation method because it is easy method to multiply plants on large scale and develop uniform quality produce.

Plant propagation is the science of generating new plants. Basically, in plant kingdom, the plants multiply themselves either asexually or by sexual means. In asexual propagation methods, plants use any of the vegetative part of the plant to produce offspring such as stem, root, buds, etc. The plants thus produced are having exactly the same genetic blueprint as that of the parent plant. However, in the sexual method of propagation, the specialized parts of the plants which have undergone meiosis takes parts such as pollen and ovule to produce seed which on germination produces the plants having characters encoded on its genome. Such plants may have a blend of characters of both the parents. The seed production is a complex phenomenon which takes place after fertilization (Bhatnagar and Johri, 1972).

In global competitive agriculture market, the need of the hour is to provide uniform and quality agricultural produce which can compete in market and give remunerative returns. For this, the agriculture production needs to be addressed on more scientific grounds and full package of practices are to be adopted to produce quality produce for global market. Earlier, the orchards were established using seedling material where uniformity of the produce was not guaranteed. Thus, in recent years more emphasis is being paid on scientific establishment of orchards which requires true to type planting material from which uniform produce is expected. This true to type planting material can only be produced by vegetative methods. Thus, standardization of vegetative propagation in horticultural crops, particularly in perennial crops has gained much importance. Some references are available on propagation of plants which shows that vegetative propagation  methods were also practiced in ancient time as mentioned in old treaties literature viz. Upvan vinod,  Ain-e-akbari, etc.

Micropropagation refers to the production of plants from very small plant parts, tissues or cells, grown aseptically in a test tube or containers under controlled nutritional, environmental and aseptic conditions. It is also called as in vitro propagation, which implies clonal, true-to-type propagation of plants by a variety of tissue and cell culture methods and is considered as the most efficient and commercial method of plant propagation. Tissue culture or in vitro culture is two broadly used terms for micropropagation, which basically include aseptic culture of various plant parts. Micropropagation was developed as the result of accidental findings of French Professor G. Morel in 1958, when he was attempting to obtain virus-free plants through meristem culture in dahlia and orchids. All the biological principles of micropropagation technique are based on the phenomenon of totipotency of cell, in which a cell of a plant has the capacity to regenerate in to a full-fledged plant having different organs. German plant physiologist, Haberlandt (1902) is known as the father of tissue culture technique, who for the first time coined the term totipotency.

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.

The classical idea of the existence of a hormone as a chemical  messenger was first reported by Darwin and Darwin (1880). However, Boysen-Jensen (1911) was first who actually demonstrated their prescence by a grafting experiment. Evidence  exist to show that early mankinds often  used these phytohormones  for rooting of cuttings, flower  induction, control of flower drop etc. The  modern age of phyto-hormones began in 1926 when  F.W.Went isolated  an active substance from oat coleoptile  tip which later on proved as IAA (Indole Acetic Acid) or auxin. A dramatic revolution in this field started after the discovery that a chemical  different in structure to IAA could exhibit auxin like activity such as rooting of cuttings (Zimmermann and Wilcoxon,1935) and by 1940,the use of synthetic auxins was well established with the progress in this field, the first generation phytohormones have been replaced with superior product and new crops are being added to take the advantages of its beneficial effects.

Besides edapho-climatic constraints in the arid region, availability of genuine planting materials at the doorsteps of the farmer’s is one of the major challenges that come in the way of horticultural development at commercial venture. Though, establishment of nursery is considered as remunerative farming enterprise if managed properly, in arid region it is still confined in the vicinity of big cities. It is also interesting to reveal that in the state like Rajasthan, most of the private nursery men are not producing planting materials in their nurseries except for the fruits like ber, lasoda and  kinnow instead they are purchasing planting materials from the other states in bulk and selling them on higher rate to the farmers of the state. The main reasons for poor development of nursery in the arid region are; unfavorable edapho-climatic conditions and poor knowledge about innovations made in recent past for nursery management. Keeping these facts in view, there is a need to develop a long chain of hitech-nurseries coupled with Human Resource Development for mass multiplication of quality planting materials for fulfilling the demand of end users. Production of quality planting material is directly link with productivity of fruit crops (Bose et al., 1998; Brison and Adriance, 2000).

Ber (Ziziphus mauritiana Lamk. ) is one of the ancient and common fruits of the country. It is a drought hardy fruit tree and can grow successfully even under harsh climatic conditions. Ber is well known for its ability to thrive under adverse conditions of salinity, drought and poor marginal soils. However, for good tree’s growth and yield, deep sandy loam soils with neutral or slightly alkaline reaction and good drainage are most suitable. It is grown throughout the country especially in arid and semi- arid parts. However, it is mainly grown in western parts of Rajasthan where rainfall is less and erratic (Pareek et al, 2002). In addition to Rajasthan state, it is cultivated in other states like U.P., Karnataka, Maharashtra, Tamil Nadu, A.P., Gujarat, M.P., Chhatisgarh, Haryana, Punjab and Bihar.

Pomegranate  (Punica granatum L.)  also  known as anar, dalim  is   an ancient  fruit and cultivated in semi-arid to arid regions of the country. However, pomegranate plants are found throughout the country from temperate to tropical climate. It has enjoyed a reputation for its healthy dietetic and medicinal properties. Pomegranate has versatile adaptability, drought tolerance, high value fruits, steady and high yields of the crop (Vishalnath et al., 2007). The pomegranate fruit has therapeutic value (Julie Jurenka, 2008); good keeping quality, high export potential and is mainly grown for table purpose, though several value added products are also available.

Date palm (Phoenix dactylifera L.) known as Khajoor, Kharek is an important fruit tree of semi-arid and arid regions of the world. It grows well under poor desertic soils due to its hardy plant characteristics and deep root system.  It is also one of the most suitable fruit plant, which can be easily grown under saline irrigation conditions. It is well known fact for date palm that its feet in the water and its head in sun. It requires dry hot climate for growth and development of fruits. In arid region, crop production is risky preposition, where date palm cultivation contributes in achieving food security, high nutritive value food, crop diversification, desertification control, income generation and foreign exchange earnings. It can be grown at such areas where adequate irrigation facilities are available besides other climatic requirements (Chandra et al., 1992; Sharma and Singh, 2013).

Indian gooseberry or aonla (Emblica officinalis Gaertn.), is an important fruit crop of 21st century and it has been regarded as ‘Amritphal’ in ancient literature, and has been identified as an ideal plant for various kinds of wastelands viz, moisture stress, eroded, ravines, upland, riverbed and the areas with undulated topography (Korwar et al., 2006) as it possesses some specific characters like intensive and deeper root system, summer dormancy of zygote, reduced leaf area, synchronization of fruit growth and development with moisture availability period and selective absorption of cations and anions which enable it to grow in fragile agro-climatic conditions. India is principal aonla growing country and Uttar Pradesh is the leading state and Pratap garh district, U.P. is well known for aonla cultivation throughout the country. Aonla is a deciduous tree, small to medium in size and distributed in tropical and sub-tropical forests in India. Looking to its high demand and value added products, now, it is being commercially cultivated in different parts of country. It can tolerate alkalinity and salinity and can be grown in wide range of soils.

Bael (Aegle marmelos Correa.) also known as Shri Phal, Baelpatra, Bengal quince, Beel, Bel is a nutritious and medicinal fruit plant, which is most suitable for water scarce areas of the country. It is indigenous tree to India and known since ancient time. Bael fruit is mentioned in ancient literature viz., Vedas, Ramayana, Upavan Vinod,  Brihat Samhita (Singh and Roy, 1984). Methods of ripening of the bael fruit are also given in Buddhist and Jain literature 800 BC – 325 BC.  During the Ramayana period, it has been mentioned that bael trees were found growing in the Chitrakut hills and Panchvati. The bael is grown throughout the country and main bael growing states are Uttar Pradesh, Bihar, Madhya Pradesh, West Bengal, Odisha and Rajasthan. It is found growing in neighboring countries like Nepal, Sri Lanka, Pakistan, Bangladesh, Myanmar, Thailand and most of the Southeast Asian countries. Besides systematic orchard, bael can also be grown in parks, temple gardens, roadsides etc. The bael plant is sacred to the Hindus and is of common occurrence in temples of ‘Lord Shiva’ because of its mythological significance.

Karonda (Carissa carandas L.) is found growing throughout India, mainly in the semi-arid  and arid regions. It is widely cultivated in the home gardens, farmer’s fields and orchards as hedge plant. Karonda is commonly used as a condiment or additive to Indian pickles and spices. Karonda is one of the few fruits indigenous to India while 30 species of genus Carissa have been reported; many species are found growing wildly in India while other species came from Malaysia and South Africa (Hayes, 1957). It is cultivated throughout India in tropical and sub-tropical areas for fruits (Rai and Gupta, 1996). In India Carissa are found growing most widely in plains and  Siwalik hills and grow wild in Deccan Peninsula, Maharashtra along the western ghats, parts of Gujarat, Punjab, lower ranges of J & K, U.P., Uttarakhand, Chhattisgarh M.P. and Aravalli hills, Mount Abu (Rajasthan). It also cultivated in other countries like Bangladesh, South Africa, U.S.A., Denmark, Ghana, Israel, Nepal and Pakistan.  It is also grows in the Sri Lanka lowland rain forests. It can be grown in any type of soil however; it is most suitable for planting in marginal lands (Sharma and Badiyala, 2002). It is a very hardy, drought-tolerant plant that thrives well in a wide range of soils. However, it is susceptible to very low temperature/frost under hot arid conditions (Singh et al., 2012).

Fig (Ficus carica  Linn.)  also called ‘Anjeer’ is a nutritive and delicious fruit. Its tree is native to western Asia. It is rich in calories (269), protein, and calcium (higher than milk), iron and fibre content. The small deciduous plants of fig are grown in different parts of the country. Fig has been cultivated since ancient period (4000 BC.) and well known through out the world. It is originated in Middle East and naturalized in many parts of the world. Fig tree plantations cover 426,244 ha. area in the world with an overall yield 1070676million tones. The largest fig growing countries are Turkey, Egypt, Iran, Greece and Algeria (Pasqual and Ferreira, 2007). It is also grown in some parts of Australia, California, New- Zealand and Argentina.