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The propagation of plants has been one of the fundamental occupations of mankind since civilization begins. Most of the selected plant would have lost or could have attained undesirable forms if they were not propagated under strict environment conditions. Growth, in all nature, result from the division of cells to form more similar cells. Thus bacteria reproduce by simple division, in higher plants and animals, a new individual is genetically formed only when cell division fallows the fusion of two cells. This is known as sexual reproduction. There are thus two methods of producing new plants, sexual and asexual or vegetative reproduction.

I. Sexual Propagation

Raising of plants by means of seeds is called sexual propagation. There are many plants raised for our garden from seeds. The plants produced through seeds are called seedlings. In sexual method, the sex organs of flower are involved in process like pollination and fertilization, resulting the formation of seeds. eg rootstocks plants of many fruit crops are grown through seed propagation.

Plant propagation by means of seed is called ________ propagation.

A. Sexual          B. Parthenocarpy

C. Asexual        D. Apomixis

The woody perennial shrubs have been the integral part of the traditional agro forestry system in arid region since ancient times. Inhabitants of the region rely on these species for food, fodder, fuel wood and other day-today requirements since long. Among woody perennials arid shrubs also have a major role in stabilization of drifting sands in the arid ecosystem. Out of about 682 species of Indian arid Zone (Bhandari, 1990), shrubs constitute 70% of the total flora in the Indian desert, yet they cover over 70-80% of desert landscape. Thus shrubs are less in variety, they are ecologically more successful biotypes in the desert environment.

The propagation of plants has been a fundamental occupation of mankind since civilization begins. Agriculture started some 10,000 years back when ancient people learned plants and grow kind of plants that fulfilled nutritional needs for themselves and their animals (Hartman et al., 1981). As civilization advanced, people added to the variety of plants cultivating not only for additional food crops but also those that provided fibres, medicine, recreational opportunities and beauty. From the great diversity and variation in plant life, it has been possible to select kinds of plants particularly useful to the welfare of humans and their animals. Bio-diversity has attracted the world wide attention because of growing awareness of its importance on the one hand, and the anticipated awareness depletion on the other. About 20 per cent of all species are expected to be lost within 30 years and 50 per cent or more by the end of 21st Century (Myers, 1993). India is one of the 12 mega-diversity countries globally recognized for its rich diversity, since its geographic position extends from sea level to the highest mountain ranges in the world.

Propagation

Definition: Multiplication of plant is termed as propagation.

Types of propagation

There are mainly two types of propagation

1. Sexual propagation
2. Asexual propagation

Seed spices, an important group of horticultural crops, are defined as vegetable products or mixture thereof, free from extraneous matter, primarily used for flavouring, seasoning and imparting aroma of foods item and beverages. Besides food industry, the seed spices have medicinal properties and thus are used in various pharmaceutical preparations and cosmetics (Malhotra and Vashishtha, 2008).  India is known as the home of spices and produces a wide variety of seed spices- coriander, cumin, fennel, fenugreek, ajowan, dill, nigella, celery, anise and caraway. Over the years a good number of high yielding varieties have been developed under AICRP on Spices of ICAR by SAU’s and National Research Centre on Seed Spices. India enjoys the status of largest producer of seed spices in the world but the productivity in the country is very low and is 25-30 % of the total potential of the crop varieties.

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.

Abstract

The studies were conducted during the years 2002 and 2003, to standardize the best method and time for summer budding in walnut. Four methods of summer budding viz. chip, annular, patch and shield were performed at 10 days interval from 15th May to 24th July. The results revealed that among the four methods of summer budding, chip budding was found to be highly superior to other methods of budding and gave 92% bud take success on 25th May and 87 per cent on 15th May also. Annular budding performed on 14th June was found next superior method and time of budding for walnut propagation when it resulted in 81% bud take success. Chip budded plants attained maximum height and radial growth as compared to annular and patch budded plants. The period from mid of May to first week of June was considered as optimum time for chip budding and mid June to end of June for annular and patch budding for walnut propagation under mid hill conditions of North-western Himalayas.

2.1 INTRODUCTION

Several propagation structures are helpful in propagation of horticultural crops. These structures are helpful for seed germination, rooting of cuttings, layering, grafting etc. and other hardening operations. The structures which facilitate propagation of plants are called propagation structures. Propagation structures are required for propagating plants by seed, cuttings and grafting.2.2

GREENHOUSE

Greenhouse is a structure covered with glass or polythene for protection against adverse climatic conditions as well as to provide optimum environment for growth of the plants. Greenhouse has been used long back by horticulturists as a means of forcing rapid growth of plants and extending the growing season particularly in colder areas. Plants are grown or cuttings are rooted in a greenhouse when the atmospheric condition does not permit for raising them in outdoor conditions. Modern greenhouses are equipped with regulatory mechanisms for controlling temperature, light intensity, air, humidity etc. Plants in green house are grown in the ground bed or bench type raised beds. The size of the greenhouses and dimensions of beds vary according to the need of propagators. Glass covered greenhouses are expensive but they have long life. However, for short-term benefits, plastic covered greenhouses can also be made. Plastic covered greenhouses are lighter than glass covered ones but there is increase in humidity is such houses, especially in winters, which results in undesirable water drops on the plants. It can however be overcome by making adequate ventilation. Polyvinyl chloride (PVC) has also been used in construction of greenhouses but it tends to darken pre-maturely in sunlight. In India, construction of temporarily low-cost poly houses is in fashion for raising nursery of fruit plant in off-season. Such low-cost greenhouses are constructed either on wood or metal framework and are covered with polyethylene sheet of 0.10 to 0.15mm thickness, which is resistant to ultra-violet rays. These houses are equipped with thermostat, cooler or an air conditioner or humidifier etc for rigid control on temperature and humidity. Greenhouses made from fibre glass sheet are more durable than the polythene houses, but are quite expensive. In greenhouses, two types of beds are used for raising seedlings. In greenhouses, the beds may either be prepared on ground itself or raised beds or bench type beds are used. Greenhouse structures vary from elementary home constructed to elaborate commercial installations.

1. DEFINITIONS

Propagation : Propagation of plants may be defined as the controlled reproduction of plants by man to perpetuate selected individual or groups of individual plants which have specific value to him or it is the perpetuation of plants as independent units by means of seeds, bulbs, layers, cuttings, or grafts.

• Seed: A seed has been defined as a young plant packed ready to start growing when required.
• Apomixis: Development of seeds without the complete sexual process is known as apomixes and seed produced in this manner is called apomictic seeds.
• Seed dormancy: The embryo of the seed remains in inactive stage from the time of its development to the time it germinates. This failure of the embryo is termed as dormancy of the seed.
• After-ripening: Some seeds germinate fully when freshly harvested, but they germinate after a period of dry storage. The change taking place in such seeds are known as after- ripening.
• Embryo dormancy: Conditions existing within the embryo.
• After-ripening dormancy: Seeds fail to germinate when freshly harvested, but they germinate after a period of dry storage. Such seeds are known as after-ripening dormant seeds. This is due to the physiological changes taking place in embryo.

Guava, Psidium guajava L., belongs to the family Myrtaceae, which comprises 3,000 species under 80 genera. It is well-distributed in the tropical and subtropical regions of the world, especially in South America, Asia and Australia. The genus Psidium has about 150 shrubs and P. guajava is wellknown and grown worldwide. The flower of guava is self-pollinated; cross pollination, however, is estimated to be around 35% and pollination mainly carried-out of by bees and other insects. Therefore, seed multiplication will result in genetic heterogeneity that can be observed in orchards and plants in the same orchard. Therefore, seed propagation in commercial orchards to increase productivity is not recommended. The methods of vegetative propagation have been studied for the purpose of the production chain. In addition to the propagation structure, the costs of new technologies must also be taken into account.
Progress in guava propagation has taken place in the last 100 years. It is important to know how to use the same methods of graftings and cutting. Detection of growth regulators, information on role of the juvenile stage in reproduction, advances in knowledge of chimeras, micro-propagation and application of vegetative propagation to prevent diseases caused by viruses and other pathogens. One can propagate guava by buddings, air layering, stoolings and inarching are not yet commercially feasible due to different success rates, the lack of a tap root system and burdensome processes. The purpose of this review is to discuss the diverse methods of propagating guava which are used commercially and the advancement made in recently.

Plant propagation techniques refer to the methods by which the plants are multiplied and increased in number.

Methods of Propagation

i) Sexual Method of Propagation - Seeds are used as propagating material.

ii) Asexual Methods of Propagation - Plant parts, other than seeds are used for plant propagation.

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).

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.

Kewda is exclusively propagated through ground suckers and leaf bearing terminal cuttings. In kewda growing areas, predominantly the terminal shoot cuttings are used in commercial plantations. However, the seeds are also capable to germinate and give rise to plants, but it is not in practice due to hard mesocarp and seed coat (Bailey, 1950, Deshaprabhu, 1966, Mott, 1975, Maharana and Jagadev, 1993).

Seed propagation

In kewda, the flowers develop into berries, which fuse to form a multiple fruit. The receptacle and bracts are included in the fruit. The seeds are deep seated and very difficult to extract, hence seeds are sown along with the fibrous drupes. Each drupe contains 2-9 seeds. Seeds collected from ripe fruits are sown during spring. The seeds normally, take about 3 months for germination due to the hard seed coat and impervious fibrous covering. Experimentally, it was observed that one hour sulphuric acid scarification treatment of the drupes reduced the germination period by about one month increasing the germination percentage as compared to direct sowing, however, scarification for more than one hour was deterimental (Table 14) (Maharana and Jagadev, 1993). Bailey (1950) reported that seed soaking in tepid water for 24 hours would aid the germination. The seed propagated plants (Plate-27) take about 2-3 years more for flowering as compared to vegetatively propagated plants.

As stated by Murashige’s definition, artificial seed (or synthetic/synseed) technology was initially restricted to species in which somatic embryogenesis was possible. Later, Bapat and co-workers (1987) proposed to broaden the technology to the encapsulation of various in vitro-derived propagules, and they used axillary buds of Morus indica as a first example of this new application. The new concept paved the way for the encapsulation of explants other than somatic embryos, and to the formulation of a new definition of artificial seeds (Aitken-Christie et al. 1995) as “artificially encapsulated somatic embryos, shoots, or other tissues which can be used for sowing under in vitro or ex vitro conditions”. In other words, the “new” artificial seed, lost the original bond of containing an embryo (zygotic or somatic), can now contain any kind of explant from tissue culture (such as axillary buds, shoot tips, nodal segments, bulblets, protocorms, callus samples, cells) which, following ‘germination’, will evolve into a plantlet or a shoot (artificial seed conversion) or will produce new cell proliferation (artificial seed regrowth).

Realization of synthetic seed technology requires manipulation of in vitro culture system for large-scale production of viable materials for preparation of synthetic seed, subsequently conversion into complete plants under in vitro as well as in vivo conditions. Somatic and gametic embryogenesis that enhanced axillary bud proliferation are the efficient techniques for rapid and large-scale multiplication of desirable plant species. Plant tissues such as somatic embryos, apical shoot tips, axillary shoot buds, embryogenic calli, and protocom-like bodies are potential micropropagules that have been considered for creating synthetic seeds. Encapsulations of somatic embryos, apical and axillary shoot buds, and regeneration of whole plants from them have been reported for a number of plant species (Redenbaug et al., 1986; Mathur et al., 1989; Ganapathi et al., 1992; Lulsdorf et al., 1993).

General Instructions

The monitor of ultrasound machine should be placed at the eye-level. The daylight should not be too bright. The setting of the machine should be done to obtain best picture on the screen. There are various knobs on the machine to set contrast and brightness. There are three other knobs that are used to set near gain, far gain and overall gain. There is also a brightness bar (help-bar) on the screen with different brightness areas. These knobs should be turned clockwise or anti-clockwise, so that all the areas on the help bar (brightness bar) are visible.

Transrectal Procedure

In cattle, trans-rectal ultrasonography is done in a way, similar to rectal examination done for palpation of genital organs. Following steps are suggested for proper procedure

1. Properly restrain the animal.

2. Evacuate the feces from the rectum.

3. Select a transducer of proper frequency (the linear array transducer of 5.0 MHz frequency is useful for general purpose in bovines, however for detailed examination of early conceptus and small follicles, a transducer of 7.5 MHz can also be used. Some transducers have range of these frequencies in single-equipment. Such transducers of switch-able frequency are found more useful.

Plant nutrients are naturally components of the soil orchestrated by weathering processes and that the abundance of these metals in our soil environment now-a-days is due to numerous anthropogenic activities. In the environment, heavy metals are partitioned among the various environmental compartments such as water, soil, suspended solids and biota. Processes such as dilution, dispersion, sedimentation, adsorption and desorption govern their distribution. They also exist in colloidal ionic particulate and dissolved phases,  have a high affinity for humic acids, organic colloids and oxides coated with organic matter. The soluble forms are generally ions or unionised organo metallic chelates or complexes. The solubility of metals in soil and groundwater is predominantly controlled by pH, amount of metal, cation exchange capacity, organic carbon content, the oxidation state of the mineral components and the redox potential of the system.

Physical Properties of Soil

Physical properties of soil have many important roles in the crop production. The basic requirements for germination, seedling emergence and root development are adequate moisture and aeration, optimum temperature and absence of mechanical hindrance. After germination the further development of plant is also governed by physical conditions of soil. Soil texture, soil structure, soil density, soil consistence, soil water, soil air, soil temperature and soil colour are main physical properties of soils also affecting mechanical behaviour of soils. These are described here.

1. Soil Texture

The weathering divides larger particles of rocks and minerals in to the smaller ones. This process goes continuously. Thus, particles of different sizes ranging from large fragments of rocks to the very fine clay minerals are found in soil. However, for texture particles less than 2mm diameter is considered. The relative amount of these particles indicates the soil type also. Such as sandy soils contain more amounts of coarse particles i.e., sand and clayey soils are rich in fine particles. The rock and mineral particles having diameter less than 2.0 mm and come between specifies size are called as soil separates. International society of soil science (ISSS) and United States Department of Agriculture (USDA) systems are Generally, followed to classify the soil separates. This classification is given in table 3.1.

Strength

Carbon nanotubes are the strongest and stiffest materials yet discovered in terms of tensile strength and elastic modulus respectively. This strength results from the covalent sp² bonds formed between the individual carbon atoms. In 2000, a multi-walled carbon nanotube was tested to have a tensile strength of 63 gigapascals (GPa). (This, for illustration, translates into the ability to endure tension of 6300 kg on a cable with cross-section of 1 mm².) Since carbon nanotubes have a low density for a solid of 1.3 to 1.4 g·cm”³, its specific strength of up to 48,000 kN·m·kg”¹ is the best of known materials, compared to high-carbon steel’s 154 kN·m·kg”¹. Under excessive tensile strain, the tubes will undergo plastic deformation, which means the deformation is permanent. This deformation begins at strains of approximately 5% and can increase the maximum strain the tubes undergo before fracture by releasing strain energy.