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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.

Plant propagation is one of the important fundamental aspects since the time of Rigveda (1400 B.C.) in the horticulture industry. It refers to the multiplication or perpetuation of individual or group of plants having specific value. Agriculture began, when ancient people started domestication of certain plants by growing around them and now these are cultivated in much improved form due to continuous selection and maintenance of better plant types. During the process of civilization; many plant types were selected for food and other purposes and are classified as food crops, fodder crops, fruit crops, vegetable crops, spices and condiments, aromatic and medicinal plants, etc. Now due modern plant sciences; newer and better plant types came into commercialization for cultivation. However, to maintain their qualities; it needs their propagation to keep their original form. Thus, it indicates that plant propagation has paramount importance in the horticulture industry to supply true-to-type sapling to farmers.

Plant propagation: Plant propagation means multiplication of plant by sexual or asexual method.

There are two type of plant propagation

1.    Sexual propagation

2.    Asexual propagation 

A. Sexual propagation: Sexual propagation means multiplication of the plant by seed. It is also known as seed propagation.

Advantages of sexual propagation

1.    This is the easier and cheaper method.

2.    Some of the plant does not response well by asexual method (Papaya) this type of plant only propagated by sexual propagation.

3.    Sexually raised plant are long lived have extensive root system and bear heavily as compare to asexually propagated plants.

4.    Hybrid can develop only by seed propagation.

5.    Seed can be store for longer duration.

ABSTRACT

Young buds of ginger (Zingiber officinale Rosc.) were isolated and cultured on MS media with BA 3 mg l^-1 induced shoot organogenesis. Young buds from aseptically grown cultures were evaluated for the effectiveness on embryogenic callus production on different concentration of auxin in combination with cytokinin. Among the plant growth hormones tested a combination of 2, 4-D 1 mg l^-1 and BA 0.5 mg l^-1 was most effective in inducing and maintaining embryogenic cultures. The somatic embryo germinated on half strength MS medium supplemented with 3 per cent w/v sucrose and 3 mg l^-1 BA.

ABSTRACT

Protoplast isolation in orchids is considered to be a valuable tool for introduction of desirable traits through somatic cell fusion. The present work on the protoplast in Dendrobium var.sonia is undertaken with a view to standardize protocol for isolation and regeneration. Tender leaf mesophyll tissues of one-month-old Dendrobium var.sonia were used as explant for protoplast isolation. The leaf tissues were treated with enzyme mixture of cellulase 1per cent (Onozuka -R from Trichoderma viride) and macerase 0.25per cent (from Aspergillus niger) for 16 hours. Protoplast from the Dendrobium var. sonia was successfully isolated and regeneration of shoots and roots were obtained in MS medium containing BA 5mg l^-1+NAA 1mg l^-1.The plantlets were hardened in a span of five months.

The productivity of a crop is result of genetic make-up (heredity) and environment (climate) and their interaction. The components of crop environment or climate or microclimate are light, temperature, air compositions and the nature growing medium or soil. In open fields, only manipulation of nature of the soil or root medium by tillage, irrigation and fertilizer application is possible. Under greenhouse structure control of any one or more of the components of the micro climate is manipulated.

Light

The visible light of the solar radiation is a source of energy for plants. Light energy, carbon dioxide (Co2) and water all enter in to the process of photosynthesis through which carbohydrates are formed. The production of carbohydrates from carbon dioxide and water in the presence of chlorophyll, using light energy is responsible for plant growth and reproduction. The rate of photosynthesis is governed by available fertilizer elements, water, carbon dioxide, light and temperature. The photosynthesis reaction can be represented as follows

For plant analysis to be meaningful, collection of particular plant part(tissue) at the right stage of growth is very important. A research worker in soil fertility is generally interested in finding out the nutrient uptake by crop at different stages. The stage at which nutrient uptake is to be studied will vary with different crops. One may also be interested in collecting a plant sample when some abnormality is observed in the plants and a nutrient deficiency or toxicity is suspected. In such cases no time should be lost in collecting the sample otherwise secondary reactions that often take place in the mineral content of plants will conceal the real cause of deficiency or toxicity. In such cases only the affected plants are to be sampled as compared to general sampling technique described below.

For research projects each plot receiving differential fertilizer or some other treatment is to be sampled separately. For general advisory purposes one sample would be good enough for the entire field (not exceeding 2 hectares). One should, however, take care that the sample comes from a field or a part there of having a uniform stand. If a field is patchy and differences in stand and plant growth are obvious, each such area should be sampled separately.

Plant tissue culture is the cultivation of plant cells, tissues, or organs on specially formulated nutrients media under the right environmental conditions. A whole plant can be regenerated from a single cell. The history of plant tissue culture has been long and started with Haberlandt in 1902 when he proposed the culture of single plant cells, his experimentation never resulted in success. White (1943) became successful in culturing plant cells for the first time, however, Morel (1960) at the Institut National Recherche Agronomique in Versailles near Paris was first to demonstrate meristem culture technology. He successfully introduced tissue culture technology to the orchid industry and produced disease-free plants of grape. By the 1970s, plant tissue culture had become a formidable technology. Plant tissue culture technique has been around for more than 30 years and considered as an important straightforward technology for the production of disease-free high quality planting material and the rapid production of many uniform plants. Its application requires a sterile workplace, nursery, greenhouse and trained manpower.

Plant tissue culturing techniques have been especially important in the agricultural community over the past many years. During this time, plant tissue culture has effectively moved from the confines of small laboratories and has taken its place among broad scale techniques employed by agricultural industry.

Introduction

Tissue culture refers to the technique of growing cells, tissues, or organs under controlled, artificial conditions. This allows propagation of tissues from a small sample of cells/tissues under sterile conditions. Plant tissue culture is widely used for various purposes, including the production of disease-free plants, rapid multiplication of plants with desirable traits, genetic modification, conservation of rare or endangered species, etc. Tissue culture is a valuable technique because it enables consistent and large-scale production of plants, ensures genetic uniformity, and allows manipulation of plant biology at cellular level. In this chapter, we will discuss about the major types of tissue culture techniques and their advantages, disadvantages, as well as applications in brief.

Different Types of Tissue Culture

Callus culture involves induction and growing of unorganized, undifferentiated cell masses from an explant on a nutrient/culture medium. The part of plant used to induce callus is called explant which can be tissue, organ or part of a plant.

Organ culture is used to maintain or grow an entire organ or a part of organ in vitro. It preserves the structure and function of the organ for studies or transplantation.

Embryo culture involves isolating and growing embryos from seeds or ovules in a nutrient medium. It is used to bypass seed dormancy or rescue embryos from hybrid crosses that may not develop naturally.

Cell suspension culture involves growing dispersed cells or small cell clusters in a liquid medium under continuous shaking. This is used for large-scale production of cells, secondary metabolites, and studying cell biology..

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.

Introduction

Plantation crops are high value industrial crops with great economic importance and play vital role in trade. It contributes to environment protection and sustains a large number of agrobased industries. It has great potential for utilization of waste lands in varied agro-ecosystems like rainfed, dryland, hilly, arid and coastal, providing higher employment opportunities, nutritional security, eco-friendly, high potential for foreign exchange earnings and above all providing livelihood security to people. They contribute 25% of AGDP. Major plantation crops grown in India are coconut,cardamom,cinchona, arecanut, oilpalm, cashew, palmyra, rubber, cocoa, tea and coffee. These crops grown between 20° N and 20° S of equator occupy nearly 3.2 million ha with a production of 9.8 million tonnes. All these crops are perennial in nature and demand  labour round the year. All plantation crops enter international trade and all of them have a long juvenile period. Coconut, arecanut and cashew are cultivated by individual land  owners who are not organized to the same extent as  planters of tea, coffee and rubber.

These crops are cultivated in an extensive scale in large contiguous areas, owned and managed by an individual or a company and whose produce is utilized only after processing e.g. Coffee, Tea, Rubber, Coconut, Cocoa, etc.

Purpose: It is important that the plants occupy the same position where the pegs were placed in the field. At the time of planting the tree the peg is removed first followed by pit making to receive the plant. The plant may be with the ball of earth or without the ball of earth. While planting the tree in the pit there is every possibility that plant may not occupy the same position where the pegs were originally placed. In order to overcome this problem planting board is used. Use of a planting board ensures the planting of the plant in the correct position.

Materials and equipments: Spade, khurpi, planting board, wooden pegs and chain.

9.1 INTRODUCTION

Establishment of an orchard incurs long term investment for which it needs a very critical planning. As it is a long-term investment, plants planted in the orchard should suit to the prevailing climatic condition of that area. The land remains occupied as long as 40 to 50 years. Any mistake committed during initial year is hard to rectify later on. Proper layout of the orchard ensures optimum utilisation of land and resources for successive economic production. It becomes easy for different inter-cultural operations, harvesting and transportation of the produces. Uniform distribution of plants in the selected land in various systems of planting is done after proper layout.

9.2 LAYOUT

The proper layout of orchard aims at accommodating maximum number of trees per unit land area, maintaining adequate space for proper development of the trees and convenient orchard management practices.

Planting System

Main objective of layout is maximum number of plant accommodated in per unit area without affecting the efficiency of production. If more than one fruit is included in the orchard plan, each kind should be grouped into individual block. Similarly fruit ripened in particular season should be grouped to facilitate convenience in watch and ward, harvest and post harvest handling. Some kind of fruit trees need pollinators/pollinisers for improving the fruit set.

Layout plan- Main objective of layout is maximum number of plant accommodated in per unit area without affecting the efficiency of production. If more than one fruit is included in the orchard plan, each kind should be grouped into individual block. Similarly fruit ripened in particular season should be grouped to facilitate convenience in watch and ward, harvest and post harvest handling. Some kind of fruit trees need pollinators/pollinisers for improving the fruit set.

The system of planting to be adopted is selected after considering the slope of land, planting density, purpose of utilizing the orchard space, convenience, etc. Traditionally, six systems of planting are recommended for fruit trees. However, with the popularity of high density planting, there are some advances inplanting, especially in fruit crops.

1. Square system: This system is considered to be the simplest of all planting systems and adopted widely. In this system, the plot is divided into number of squares as per plant spacing and trees are planted at the four corners of each square, in straight rows running at right angle. Under this system, intercultural operations, spraying, harvesting, etc. can be done conveniently and easily. Cultivation and irrigation can be done in two directions. In this system, plant to plant and row to row distance is the same. e.g. 5x5m, 4x4m, 10x10m, etc.

   While laying out the plot, a base line is first drawn parallel to the road, fence or adjacent orchard at a distance equal to half the spacing to be maintained between the trees. Wooden pegs are fixed on this line at the desired distance. At both the ends of the baseline, right angles are drawn by following the simple carpenter’s 3,4,5 meter system. After the formation of three lines, it is easy to fix all the other pages to mark the tree locations at the required spacing by using ropes connecting the pages of the lines in opposite directions.

   Area occupied per plant = row to row distance X plant to plant distance

ABSTRACT

In vitro culture induced genetic variation constitutes an important source of variability for the improvement in ginger (Zingiber officinale Rosc.). Hence attempts were made to standardize indirect method of in vitro plantlet regeneration in ginger using various explants like sprouted bud, shoot tip, leaf and pseudo stem. Explants from two cultivars of ginger viz. Maran and Rio-de-janeiro were cultured in Murashige and Skoog (MS) medium supplemented with various levels of 2,4-D and in combination with different levels of BA. Cultures were incubated under two different culture conditions viz. light and dark. Callusing was observed in all the explants except mature leaf in MS medium supplemented with 2,4- D alone (1 - 2 mg l^-1) and in combination with BAP (0.5 - 3.0 mg l^-1). Shoot morphogenesis was achieved from one month old calli in MS medium supplemented with BAP (3.0 mg l^-1). Regenerated shoots were subcultured to medium of same composition for further shoot proliferation and rooting. Plantlets produced were hardened and planted out. From the present investigation, highly efficient protocol for indirect organogenesis in ginger could be developed and the response of two cultivars at various stages of morphogenesis could be studied in detail.

The use of natural dyes lost ground together with the old traditional dye methods towards the end of 19th century soon after the synthetic dyes came to the market (Gilbert and Cooke 2001). Only artisans, craftsmen, and green–minded companies continued dyeing with natural dyes (Hartl 1997). The first recorded synthetic dye is picric acid produced in 1770’s from the interaction of indigo and nitric acid. The synthetic dye industry is considered to have started when Perkins synthesised mauveine (mauve) in 1856 in the UK (Hancock 1997). With the passage of time, it was observed that synthetic dyes used by the textile industry are a source of environmental pollution (Seker et al. 2007) and they produce allergic, carcinogenic and detrimental effects on the health of humans (Singh and Singh 2002, Mahanta and Tiwari 2005). The synthetic dyes were preferred by the industry because of their simpilicity in the use and all colors could be produced easily, but the problem was the waste deposition which is a major cause of environmental pollution. The solvents used during dying reduce the problem to some extent but the waste water purification needs extra effort and money (Shreve and Brink 1985). As against this, the natural dyes are not only harmless to the humans but also cause far less environmental pollution, and have distinctive washing and sunlight fade–resistant characteristics (Mert et al. 1992, Angelini et al. 1997, Kim and Park 2006). For this purpose, the textile industries have started rethinking about the natural dyes and are trying to find sustainable as well as non–toxic alternatives to synthetic dyes for a growing textile market.