eChapters

Definition: Ground covers are low growing plants which are useful for covering large areas in the landscape Or Ground cover refers to any plant that grows over an area of ground, used to provide protection from erosion and drought and to improve its aesthetic appearance. An ideal ground cover must be easily established.

Ground covers are living plants or non-living materials used to cover areas. In general, plant related ground covers have a creeping or prostrate growth habit and grow no taller than 60 cm. A good ground cover should be evergreen and provide a permanent covering. Effects that cannot be achieved with turf grass or other plantings are possible with ground covers. Ground covers provide variation in plant height, texture and colour.

This chapter introduces environmental management and automation in greenhouse production. It explains how temperature, light, humidity, carbon dioxide and root-zone conditions influence plant growth and flower quality. The chapter discusses ventilation, evaporative cooling, supplemental lighting, sensors, automation systems, solar greenhouses and retractable greenhouses. It also introduces government support and guidelines for protected cultivation, including MIDH assistance. The chapter emphasizes precision environmental control, resource-use efficiency and technology-enabled production.

Growth and development are two important stages in a plant. Plant growth and development are under the control of both intrinsic and extrinsic factors. Growth is one of the fundamental characteristics of all living things. Even in Plants, the growth is visible but not measurable easily. Development in plants is actually a sum of two processes i.e. growth and differentiation.

Principles involved in plant growth and development: The various principles involved in plant growth and development are discussed below.

1. Totiopotency: Living plant cell has the potential to reproduce all the characteristics of the plant since it possesses all the genetic information.
2. Competence: It is the potential of cells or tissue to develop in a particular direction. Development of competency into a particular kind of cell(s), tissue or organ also may require special signals. These may originate internally within the plant or may originate externally as an environment signal, e.g. Internal change in type of growing point such as vegetative to flowering or initiation of adventitious roots on cuttings may be associated with a shift in the activity of specific hormones, external parameters i.e. application of growth regulators, or environment. It is mainly internal potential of meristem that gradually shifts from a vegetative shoot to one that produces flowers.

The term growth refers to an irreversible increase in size and weight of the plant. It normally reflects an increase in protoplasm, which may occur through increase in size of the cell and number of cells. Hence, the process of cell elongation and cell division provides the basis for growth. Cell division and enlargement are complicated processes involving synthesis of many organic compounds such as protein, cellulose and nucleic acid, besides the physical force required, which results in cell enlargement. The growth of the whole plant is compartmentalized into areas called ‘meristem’ where cell division and cell elongation are localized. The meristem cells such as shoot apex, root apex, cambium and the intercalary zones undergo repeated mitosis resulting in replication of DNA and nuclear material and finally the cell mass increases. Adjacent to this area of meristematic activity is the region of cell elongation, which phases in to the region of differentiation and maturation.

The increase in protoplasm (occurring in cell division and elongation) is brought about through a series of events in which water, carbon - di-oxide and inorganic salts are transformed into living materials. These events include (a) photosynthesis (production of carbohydrates) (b) nutrient absorption and translocation (uptake of water, nitrogen and other mineral elements) and (3) anabolism (synthesis of various materials produced in plant from the carbon fragments produced by photosynthesis and from the inorganic nutrients and water absorbed from the soil). The energy required for all these processes is provided by a catabolic process viz., respiration (degradation of sugars and fats to release energy). The net balance of anabolism and catabolism results in growth of the plant.

11.1 INTRODUCTION

Plant growth regulators have remained an important component in horticulture from time immemorial because they were effective means of quantitative as well as qualitative improvement in growth and development of crops. Plant Growth Regulators (PGR) are diverse group of organic compounds other than nutrients, produced artificially or by plants which in low concentrations promote, inhibit or modify the physiological process in plant. The term includes both naturally occurring phytohormones as well as synthetic compounds. These are produced naturally in higher plants, controlling growth or other physiological functions at a site remote from its place of production and active in minute amounts. Plant Growth Regulators are used in different forms like liquid, powder, paste etc. “Hormone” is Greek word derived from “hormao”, which means to stimulate. Thimone (1948) suggested the use of term ‘phytohormones’ as the organic substance, which are produced naturally in plants, synthesised in one Part And usually translocated to other part wherein every small quantity affects the growth and other physiological function of the plants. To distinguish them from the animal hormones they are termed as phytohormones. Auxin was the first hormone to be discovered in plants and at one time considered to be only naturally occurring plant growth hormone. The role of plant growth regulators in various physiological processes such as seed germination, f lowering, fruiting, seed development, fruit ripening and yield etc. in different crop plants is well established (Kiran et al., 2011). There are five classical phytohormones: auxins, gibberellins, cytokinins, ethylene and abscisic acid. Besides classical phytohormones a variety of other compounds that play roles in plant growth and development have also been identified, including jasmonic acid, salicylic acid, brassinosteroids and polyamines (Basra, 2000). The application of plant growth regulators in agriculture has started in 1930 in the United States. Ethylene, a naturally occurring substance, is one of the first plant growth regulators being discovered and used successfully for enhancing f lower production in pineapple (Fishel, 2006). Its toxic effects to human beings are low.

Guava is one of the most common fruits grown widely throughout the tropical and subtropical regions of the world. Guava is hardy in nature, prolific bearing and highly remunerative even without much care (Mitra and Bose, 1990). Because of its excellent adaptability and exceptional performance in the tropics, it is regarded as the ‘apple of tropics’.

In India, guava is the fifth most important fruit crop in terms of area and production. It is cultivated over 1.51 lakh ha area with a total production of 18.0 lakh tones (Chadha, 2001). It is rich in pectin and used for jelly making. It is useful as table fruit and also for processing purpose.

It is known by different names viz., madhuri (Assamese), peyara (Bengali), phanas (Gujrati), amrood (Hindi), sebe (Kannad), soh-priya (Khasi-Meghalaya), komperam (Garo-Meghalaya), pera (Malayalam), peru (Marathi), pijuli (Oriya), amrud (Punjabi), koyya (Tamil) and jama (Telugu).

Gypsophila is herbacaeous annual or perennial flowering plant belongs to family Caryophyllaceae. It contains several ornamental species of which Gypsophila paniculataL. is the only species used as a cut flower (Zvi et al., 2008) and it is applied as filler in flower arrangements (Jones, 1995 and Rehman, 2002). Gypsophila derived from “gypson” meaning chalk and “phylos” meaning lover, an etymology which alludes to its preference for calcareous soils (Vettory et al., 2013). Mainly found in temperate or warm-temperate regions in the Northern Hemisphere, best developed in the Mediterranean region and Near East (Ataslar et al., 2009 and Cronquist, 1981). It is a perennial plant often grown commercially as an annual crop. Root is rich source of triterpine saponins (Henry, 1993, Hostettmann, 1995 and Gevrenova et al., 2010) which are used for commercially in medicines, detergents, adjuvents and cosmetics (Hostettmann, 1995, Tschesche and Wulff, 1973 and Gevrenova et al., 2010). G. paniculata is one of the ten best selling cut flower species worldwide and thus becomes for the genetic improvement and selection of new varieties of commercial interest. Main regions of gypsophila production are Italy, Israel, Belgium, Germany and Holland while currently its cultivation is spreading across to other countries such as Ecuador, Egypt and Kenya due to lower labour costs. Infact, Gypsophila is among one of the most important varieties of cut flowers in Israel, where it is grown in more than 200 hectares of greenhouses and is almost entirely exported. For these reasons, the competition has increased dramatically, making the world market increasingly difficult for companies which feel the need to introduce new varieties that respond better to characteristics desired by consumers and florists.

Introduction
Genus Curcuma belongs to the Zingiberaceae family, and containing of about 122 species. These are grown profusely in Asian countries including, India, China, and Southeast Asia, Northern Australia and New Guinea. Like ginger, it is also the popular herb of this family for the utilization of its underground rhizomatous stem by human beings. Botanically it is named as Curcuma longa L. Its bright yellow spicy powder is got from the dried rhizome is termed turmeric powder, which is the final product of this herb. In addition to this curcumin bio-active compound is also extracted by cursing rhizomes of turmeric. The plants turmeric are considered to be a hybrid and sterile leaving vegetative propagation from rhizome as the single mode of propagation. India is recognized as the power house of turmeric production. Along with us, our neighbours in South East and Eastern region, including Malaysia, Thailand, Bangladesh, Cambodia, Philippines, Indonesia and even China are considered major producers.
Floral Biology
All species of Curcuma genus have almost alike flowering spikes that mainly originate from the topmost region of the rhizome (pseudo-stem) or sometimes on a separate stem directly from the rhizome. These two stems differ onlyin the inner portion of rhizome, which differ in colour, i.e., creamy, white, orange, yellow, bluish-green, blue, and sometime black also. The rhizomes exhibit commercial value as a medicine as well as food spice. Curcuma longa L. (Syn. Curcuma domestica Val.), is the common turmeric. It is the top ranking herb based on its economic potential among all the members of this genus and cultivated in India about 150,000 hectares.

India is predominantly an agriculture based country and 65% of the Indians depend on agriculture. To meet the ever increasing nutritional demands of Indian population, production and productivity of vegetables have to be increased manifold within the limited available land and other resources. Seed is the basic and critical input in which the expected dividends from all other inputs depend and it plays a crucial role for enhancing the stability of productivity. With the ever increasing demands for a mechanized, energy efficient type of agriculture, each seed is expected to produce a vigorous plant, which would develop. uniformly under a wide range of environmental conditions.

Seed enhancement technologies have historical basis dating back hundreds to thousands of years. Seed coating was being practiced by ancient Chinese farmers who coated seeds of rice with mud balls to anchor the seeds in water saturated soil . The Greeks presoaked the cucumber seeds in milk or water to make them germinate quicker. Keeping the seeds in moist cloth or soaking in water prior to sowing was a common practice among the farmers of India from time immemorial.

Introduction

Use of acid/base is common in laboratories for experiments like titration and proper safety in their handling laboratory is necessary. In this chapter we will briefly discuss about the safety measures necessary to be adopted while using acids/bases in laboratory for any experiment.

Handling of Strong Acid/Base

There are four major points that need to be taken care of while working with strong acids or bases that might be quite harmful if any accident happens.

1. Protect Yourself

Wear a lab-coat and acid-resistant gloves: Always use lab-coat/apron and make it sure that the sleeves properly cover your arms. More importantly, use gloves made of acid-resistant materials and also wear shoes to protect your feet while wearing long-pants/jeans. Female with long hair, must tie her hair properly (with rubber band) to avoid any disturbance caused by appearance in between.

Wear safety goggles: It is important to wear safety goggles to protect your eyes using larger and fitting goggles that cover front as well as sides of your eyes. Always use properly fitting and adjustable goggles because smaller/ loose goggles may not protect the areas around your eyes against accidental acid spills and it may fall down from your face, if it is too loose.

Locate emergency wash area: There must be an emergency washing area nearby the work place or laboratory containing lab spill management kits. All the workers in the laboratory must be aware of using the kits and emergency plans.

Neutralize acid: Don’t panic even if an acid or chemical spill happens. Stay calm and act as quickly as possible. In case an acid spills, neutralize it by using sodium bicarbonate so that they can be cleaned and disposed safely. If acid comes in contact of skin, wash it off under running tap water but do not use/ apply sodium bicarbonate on skin.

Introduction

For proper and efficient experiment to be conducted, experimenters need so many chemicals to deal with. This includes different acids, base, salt, different kind of indicators and so on. Some of these chemicals are safe for health, but some of them are dangerous to health when come in close proximity to our body while some of the chemicals cause health issues on inhaling. These may cause improper functioning of some of our physiological activities. Acids and bases are very dangerous for our tissues when come in our contact. These may cause serious respiratory problem in addition to injuries on coming to our contact. Some chemicals are exploratory yet they may cause even death of the person working with them in laboratory. Therefore, mere use of the chemicals in laboratory is not only the objective of the experimenter. The person working in laboratory should also be concerned about the proper use and handing of the chemical while working with it. Thus, every researcher of an institution who has to work with chemicals in a laboratory should be made aware about the chemicals to be used in the laboratory and the consequences if any mishandling of a laboratory chemical occurs. Not only these, suitable precautionary measures should also be known to the researcher along with ensuring the availability of the required safety equipment/installations. Hence, a proper understanding of the ways of handling of chemicals in a laboratory is of prime importance for the personals like you who are working or have to work in laboratory.

Safe Handling of Chemicals in Laboratory

Safe use/handling of chemicals in laboratory include minimized exposure to chemicals, maintaining safety data sheets, proper labelling, storage, segregation, and transport of chemicals for personal hygiene.

Introduction

We come across a variety of chemicals every day in a laboratory. While some of them are relatively safer, others are extremely hazardous. Thus, it is very important to know the potential hazards that can be caused by the chemicals present in the laboratory and the safety measures needed to be followed to avoid the hazards. Additionally, we should also be aware of the steps necessary to be taken on such hazardous situations. According to IUPAC, a hazardous chemical mean the chemical which has the potential to cause damage in various ways. In a laboratory, there are chemicals that might be irritant, carcinogen, respiratory fibrogen, systemic poison, asphyxiant, flammable, etc. which have the potential to cause hazard to the workers or environment. Therefore, it is important to use appropriate procedure to reduce the risk and protect the health/safety of laboratory personnel, the public and the environment.

Types of Hazards Associated with Chemicals

Chemical hazards: The hazards caused by chemicals can be broadly classified into three categories.

1. Health hazard: This is also known as toxic effects of chemical. The risk associated with a chemical in laboratory depends on the extent of exposure and the inherent toxicity of the chemical. Many chemical reactions form the product that might be much more toxic than the reacting chemicals. For example, inadvertent mixing of formaldehyde (a common tissue fixative) and hydrogen chloride results in the generation of bis(chloromethyl) ether, a potent human carcinogen. For most of the chemicals, the route of exposure (through skin, eyes, gastrointestinal tract, or respiratory tract) is more important (Figure 17.1) that must be considered during risk assessment.

Cities or urban conglomerations are fast developing and where the rate of land availability has infinitesimally small; vertical expansion and taller buildings have emerged and are defining the city skyline. Though this may speak well of the economic development, but the increase in hard paved areas and roads may spell trouble for the environment as urban heat island (UHI) effect. The causes of Urban Heat Island are primarily due to the absorption of solar radiation (Short wave) by building/urban materials that is subsequently re-radiated (long wave) to the surroundings. In addition, heat generated from the use of air- conditioning coupled with the greenhouse effect of pollutants also contribute to the increase in temperature. Such increase in temperature with the presence of air pollutants can result in the accumulation of smog, damages the natural environment and jeopardizes human health. It also costs consumers more money because it takes more energy to cool buildings. Who can forget the regular news of Beijing repeatedly topping the list of most polluted cities and fresh air is available in cans!

Fresh air cans are in no means a firm solution. Plants are atmosphere cleansers, can serve to filter carbon dioxide and other toxins in environment, cool the air by transpiration and also provide cooling shade. Research work shows the benefits of using light colour roofs and roof gardens to minimize the heat gain inside the buildings. This would in turn reduce the energy consumption of air conditioning in buildings. Rooftops, balconies and terraces have often been referred to as the “last urban frontier” of cities, in the sense that they represent the last significant remaining space to be exploited to create a green oasis and an area of relative peace and privacy away from the urban bustle. Given the social, economic and environmental contributions of urban greenery to the quality of life in cities and the realization that cities more often than not lack sufficient greenery, greening of rooftops, balconies and terraces is therefore a logical, effective and high impact way to re-inject the much needed greenery in urban settings thus reinventing the concept of hanging gardens.

Energy and food are the two main requirements for human civilization; however the demands for these two resources are increasing in a fast rate. Development of any region is reflected in its quantum of energy consumption. In this context, the situation in arid region is difficult. People burn firewood, agricultural waste and cow dung cake for cooking food causing damages to the fragile eco-system of arid zone. There is inadequate electrical power supply and hence villagers of remote arid areas are unable to derive general benefits. The kerosene is used for lighting and fast depleting diesel oil is used for running agricultural machinery including pumps. In this context solar energy is considered to be one of the promising sources in India.

About 12% of electricity production capacity in India is met through renewable energy sources. In India, national solar mission was launched in November 2009 with a target of 4000 MW grid and 1000 MW off-grid electricity generation from solar energy by the end of phase II (2013-2017), whereas these targets are 20,000 MW and 2000 MW, respectively by 2022. The target has been revised in 2015 to a total grid connected solar power generation of 1,00,000 MW comprising of 40,000 MW roof top generation and 60,000 MW grid connected solar power plants (Resolution of MNRE, Govt of India, No. 30/80/ 2014-15/NSM dated 1^st July 2015).

Kewda plant occurs wild in the entire coastal belt of Odisha , but abundant in Chhatrapur and Keluapalli areas of Ganjam district. There were about 3-4 lakhs trees of kewda in Ganjam district (Deshaprabhu, 1966). Main season of flowering starts from July-August and lasts for 2-3 months and a few flowers also come during November-December and March-May (Haines, 1961). Averagely, a plant produces 15-20 flowers per season depending on branching of the tree (Plate 32). A fully matured tree bears 30-40 spadices in a year (Deshaprabhu, 1966). Flowering is also dependant on rainfall, being better in years of high rainfall. Size of flower is bigger during rainy season. The spadices take a fortnight to mature, depending upon the weather condition. Ripe spadices, creamy in colour, give higher yield of perfume and of better quality than immature ones (Plate 33). The kewda flower of Ganjam district is also registered under the geographical indications (GI) of goods (Registration and Protection) act (Panigrahy, 2019).

4.1 Dry Flower Garden

Contrary to popular assumptions, the area required for producing large quantity of dried flower material need not also be large. However, the garden should be planned so as to harvest dry flowers all year round by planting evergreens, deciduous plants, annuals and perennials. Rows of flowering plants should be planted in the dry flower garden. Herbs are easy to grow, and can be planted in pots and window boxes. They are useful in transforming simple cooking into gourmet dishes, while also lending their delicate scents to a room when dried and for use in wreaths, pot pourri and arrangements. Gardens for dry flower production should include a wide selection of weeds, grains, seed-heads and pods. Flowers such as hydrangeas, zinnias, roses, dahlias and sunflowers and a selection of line flowers such as golden rods, statice, gladiolus, larkspur and delphinium can also be grown as these will provide a greater variety of flowers needed in flower arrangements.

It is not just enough to produce fruit and ornamental plants in a nursery, but it is also very much important to consider the post production management practices like harvesting, packing, storage and marketing of nursery plants for successful industry.

Harvesting: Harvesting is one of the important factors considered, when nurserymen are producing seeds, bulbs, etc. The seeds or bulbs should be harvested at proper maturity stages depending on the plant species.

Seeds are generally harvested when they are fully ripe. In some of the annuals and perennials, seeds are likely to fall from the plant at ripening either due to bursting of the fruit/ capsule or due to wind. (calendula, balsam). In such cases, it is better to cover with muslin cloth or butter paper bags. Bulbs, corms and tubers are carefully dug out without injury, along with cormels or bulblets.

Packaging: The package should provide a convenient mode used for marketing and distribution. It protects the contents from undue damage during distribution. It is important that appropriate packaging should be used to preserve quality of material along with maximum survival during transit. Proper packaging of plant material (fruit plants/ ornamental plants/seeds) ensures quality during storage, distribution and transport.

6.1 Introduction

Greenhouses play an essential role in modern agriculture and horticulture by providing a regulated environment for plant development. To ensure optimal growing conditions and maximum yields, it’s crucial to maintain the temperature inside these structures effectively. This leads us to the fascinating subject of “Heating and Cooling of Greenhouses,” where we investigate the delicate balance between temperature, humidity, and ventilation to promote plant health and production. With greenhouses, growing seasons can be extended, a broader range of crops can be grown, and even plants that would not do well in the local environment can thrive.

Hedge

Hedge is an important garden feature both for beautification and functional purposes. When a selected plant species is planted together at close distance, in single or multiple rows, later pruned to retain a definite shape and height is known as hedge. These are actually live fence used for demarcating road, paths and sometimes for providing physical barrier, screening and several other purposes.

Selection of Plants

Before selection of plants for developing hedge, the purpose of planting hedge is to be considered first. If the purpose is protective fence, the height and width are to be decided. Accordingly, selection of plant species is to be made. For developing low height and ornamental hedge along the passage and inner roads, selection of plants will be different. In this case, plants having colourful leaves is preferred. Final selection of plant species, however, should be done considering location, availability of sunlight and the type of garden. Plants selected for developing hedge should response well to pruning and, at the same time, acquire a definite shape on repeated pruning. Both foliage type and flowering plants are used for developing hedge.

Hedge

When shrub is planted on boundary for fencing, it is also called as hedge. In other word shrubs or trees planted at regular intervals to form a continuous screen is called a hedge. It may be ornamental or protective or both. Hedge also become an important feature of formal layout to serve various function as screening of the area out building, tennis court, vegetable garden, hardening of unwanted place etc. All the shrubs cannot be planted for making an ideal hedge due to different nature of growth.

Heliconias are tropical plants of princely dimensions grown for their attractive foliage and brilliant flower spikes. They are some of the most unusual flora of the tropics. Strikingly elegant flower heads rise from banana like clumps of oval leaves, which are sometimes rather slender and, with a few varieties, extremely large. They are found naturally in the tropical forests world wide and in moderate climates. A popular landscape plant and cut flower in tropical and subtropical areas of the world, heliconias are native to Central and South America, the Caribbean Islands and some of the islands of the South Pacific. Their easy cultivation and spectacular presence have made them favourite garden subjects throughout the world. Heliconias have several common names including lobster’s claw’s, ‘parrot’s flower’, ‘parrot plantain’ and false plantain. Depending on variety, heliconias will range in height from 60 to 700 cm, often with extensive rhizomatous growth. The flower or inflorescence of heliconia is nearly always terminal and may last from several days to several months. They are particularly desirable as cut flowers because of their long lasting characteristics. 

Heliconia belongs to family Heliconiaceae is popular as ornamental plants and cut flowers because of their brilliant colours and exotic appearance. The genus name “Heliconia” is derived from “Helicon”, a mountain in southern Greece regarded by the ancient Greeks as the home of the Muses, thus suggesting the relationship between these plants and the bananas, genus Musa (Berry and Kress, 1991). Unique features of the Heliconiaceae are (1) medium to large erect herbs rising from underground rhizomes;(2) each erect shoot is composed of a stem and leaves, whereas the stem is made up of an axis covered by overlapping sheathing leaf bases, technically called a pseudostem;(3) inverted flowers and (4) the presence of a single staminode. Heliconia has long been popular horticulturally because of their showy inflorescences. It was so attractive that early explorers of the tropics returned to Europe with several species that became prized green house specimens. Heliconia, grown in nearly all of the tropical regions of the world, including Africa and Asia. In India, heliconia is grown in North-East region and Kerala.

ORIGIN AND DISTRIBUTION

Heliconias are native only to Central and South America and some of the islands of the South Pacific, for horticultural and commercial popularity. Berry and Kress (1991) stated that they are native from Tropical America and found at different altitudes, from sea level up to 2,000 meters in Central and South America, and up to 500 meters in the South Pacific Islands (Criley and Broschat, 1992).

Most of the Heliconia species are distributed primarily in Neotropical areas from the North of Mexico to the South of Brazil (Santos, 1978, Dahlgren et al., 1985 and Kress, 1990). A small Paleotropical group, about eight species, occurs in islands of the South Pacific (Tomlinson, 1969 and Kress, 1985). There are approximately 40 Brazilian species with two primary areas of distribution: the Amazon basin and the Atlantic coastal forest (Kress, 1990). About 100 or more species, native mainly to tropical and subtropical South and Central America (Cronquist, 1981).

Several attempts have been made over the years to sort out the taxonomy of the Old World Heliconia. Baker (1893), followed by Schumann (1900) and Winkler (1930), dealt with the problem of identity and origin of these taxa by assigning them to the neotropical species Heliconia bihai L. Others such as Ridley (1908a, b), Backer (1920) and Green (1969) recognized the distinctive and endemic features of the paleotropical taxa that separated them from the neotropical species. This ornamental rhizomatous herbaceous plant from the Heliconia genus, belongs to the Musaceae family, now constitutes the Heliconiaceae family in the Zingiberales order. The various species of Heliconia are subdivided into five subgenera: Heliconia, Taeniostrobus, Stenochlamys, Heliconiopsis and Griggisia; and 28 sections (Kress et al., 1993).

This chapter introduces Heliconia as an exotic tropical ornamental crop valued for its brilliant colours, distinctive inflorescences and excellent postharvest longevity. It examines origin, distribution, genetics and botanical characteristics and discusses important commercial species and varieties. Protected cultivation practices, nutrition, irrigation, planting, pruning, plant growth regulators, pest and disease management, harvesting and postharvest handling are presented. The chapter highlights the potential of Heliconia as a premium cut flower and its suitability for tropical and subtropical regions of India.

Henna or Mehandi (Lawsonia inermis L.) a perennial shrub belongs to family Lythraceae. It is commonly cultivated as a commercial dye crop possess natural dyeing properties and are used for hair dyeing and for staining of palm, feet and other body parts since times immemorial. The plant finds their importance due to presence of orange red dye in its leaves and essential oil in its flower. Oil extracted from leaves and flower called ‘Otto of henna’ which is utilized as perfume (Jaimini et al., 2005). It can grow well in harsh climate of arid and semiarid regions. In India, over 90 percent of the henna production comes from Sojat region of Pali district of Rajasthan and Sojat is only center for its processing and trading in India. In India it occupies about 40,000 ha area out of which 35,000 ha alone is in Pali district (Sojat and adjoining tehsils).

Geographical distribution

It occurs naturally in North Africa mainly in countries of Algeria, Cyprus, Egypt, Eritrea, Ethiopia, Indonesia, Iraq, Iran, Jordan, Kenya, Kuwait, Lebanon, Libya, Malaysia, Morocco, Oman, Philippines, Qatar, Saudi Arabia, Syrian Arab Republic, Tanzania, Tunisia, Turkey, Sahara and Yemen. It is naturally occurring in many of these countries along the water courses and semi-arid regions where it can with stand dryness as well as drought. It has been introduced into countries like Australia, Benin, Burkina Faso, Cameroon, Central Africa, Chad, Congo, China, Gabon, Gambia, Ghana, Guinea, India, Liberia, Mali, Mauritania, Niger, Nigeria, Pakistan, Senegal, Sierra Leone, Spain, Sudan, Togo and Zanzibar (Suresh Kumar et al., 2005).

Distribution

Several countries grow henna on a commercial scale for its dye-bearing leaves, notably India, Egypt, Iran, Niger, Sudan and Pakistan. In India, it was once grown extensively in Punjab and Gujarat. However, gradually the major cultivation has shifted to the arid fringes of Rajasthan, with Pali district having the maximum area under henna. It is taken as an annual Ratoon crop under rainfed conditions. Presently over 39,000 ha of henna plantations in the district with nearly 70 per cent occurring in the Sojat area produce around 20,000 t dry leaves worth Rs. 40 crores. Besides this, leaf cuttings are also collected from existing farms and field boundary plantations in Gujarat and Madhya Pradesh. In Uttar Pradesh henna is grown for its scented flowers used in the essence industry. Kannauj, Lucknow, and Varanasi in Uttar Pradesh are reputed centres for the commercial extraction of mehndi oil from flowers and its use in traditional essence. Since henna is grown as a dryland crop under limited moisture conditions greater use of available moisture by the plants is possible.

The state of Jammu and Kashmir is highly mountainous except for a short belt joining the Punjab plains. Geographically, the state of Jammu and Kashmir is divided into three regions -alpine desert of Ladakh, subtropical region of Jammu and predominantly temperate region of Kashmir valley. The valley is rich in herbaceous flora with huge potential for landscape use, however, many of which are still not exploited much for the purpose. Plants which live and bloom year after year are known as perennials which have an importance of their own and are backbone of any well-planned garden. The stems of herbaceous perennials die at the ground level each winter. They comprise a vast group of plants widely differing in size, leaf texture, flower color and are found in all the gardening countries of the world. The monotonous spread of concrete and glass in cities can have a dehumanizing effect. Growing colourful flowers in the house compound and in the parks will greatly enhance the beauty of surroundings in the countryside, the towns and cities. Flowers also bring happiness to life and boast the sagging spirits. The assemblage and display of colourful and attractive herbaceous perennials can achieve very significant and telling effects on the environment particularly in the landscaping of the house compounds, gardens, parks, health resorts and hotels. Now a day herbaceous plants are also used therapeutically to cure several problems related to humans. Judicious selection of native and introduced herbaceous perennials should camouflage with the type of habitation, building pattern, colour of the countryside etc. These plants should occupy only well thought of position in the landscape. There are always a number of shady spots in our lawns/gardens especially towards north-east side of a structure where lawn grass fails to grow or show poor growth. These spots can be converted into perennial herbaceous border of foliage plants.

Trees and shrubs are often the most dominant plants in landscapes but ground covers and vines play an important role too. The low spreading form of ground covers can connect and unify major planting areas and even serve as a focal point when the plants are flowering. In contrast to annuals, perennials provide savings in time, labour and expenses each year because where adapted to a specific climate zone, they can successfully over come winter and re- establish for more than a single growing season. Perennials are probably the most diverse plant group, providing a huge variety of shape, form, colour, texture and scent with which to design a planting. Since there is an increasing trend and awareness of planned landscaping in the public and in view of its value in preserving the environment, there is an urgent need to identify and select the appropriate native, naturalized and exotic planting material for specific sites /locations. Information regarding herbaceous perennials surveyed and identified in Kashmir Valley with prospective use in landscaping are given as under:

14.1 Herbarium and Its Limitations
A collection of dried and pressed plants arranged according to a classification system and available for study or reference is known as herbarium (plural, herbaria), a name first applied by Linnaeus.
Plant specimens are usually mounted on a sheet of high quality paper. Properly dried, pressed and identified plant specimens are placed in thin paper folders (species covers) which are kept together in thicker paper folders (genus covers), and finally they are incorporated into the herbarium cupboards in their proper position. Some fleshy members (e.g. Cactaceae) are preserved in liquid preservatives instead of being pressed and dried. Bulky plant parts (e.g. dry fruits, cones of several gymnosperms, etc.) are dried without pressing and are stored in special bags.
A herbarium may contain a few hundred locally collected plant specimens kept in a small place, or it may contain millions of them collected from different parts of the world and housed in a very big building. Herbaria in different countries remain associated with colleges, universities, scientific societies, research institutes, botanical gardens or flora of a district, state, country, continent or several continents. There are also private herbaria.

13.1 Introduction

F₁ plants produced by crossing two parents with contrasting characters are called hybrids. Hybrids generally exhibit increased vigour and fitness over the parents. This phenomenon is called hybrid vigour or heterosis. Thus, heterosis is the phenomenon in which the hybrid of two genetically dissimilar parents shows increased vigour at least over the mid-parental value. Heterosis is just the reverse of inbreeding depression, which results after selfing the plants of the cross-pollinated crops. Kolreuter (1761-66) was the first to report hybrid vigour in the hybrids of tobacco, Datura, etc. Most of the early plant hybridizers including Mendel (1865) had noticed this phenomenon. Shull (1914) coined the term heterosis from two Greek words, hetero (different) and osis (condition), to replace his own earlier word ‘stimulus of heterozygosis’. In current usage, heterosis and hybrid vigour are used as synonyms and interchangeable.

13.2 Types of Heterosis

Depending on the nature, origin, adaptability, reproducibility and non-reproducibility, heterosis can be categorized into two: (1) euheterosis (true heterosis) and (2) pseudo-heterosis (false heterosis, i.e., luxuriance).

20.1 Introduction

A hybrid cultivar (also called hybrid) is the F₁ progeny of a planned cross between inbreds, cultivars, clones or populations. Depending upon the breeding approach, the hybrid cultivar may involve two or more parents. A critical requirement of hybrid production is that the parents are divergent. This divergence is the cause of superior performance of hybrids. The outstanding performance of crops is due to the exploitation of the phenomenon of heterosis (hybrid vigour) which is high when parents are divergent. Much of what we know about heterosis breeding (also called hybrid breeding) came from the work on maize hybrid cultivar development. However, commercial hybrids are now available in many crops including self-pollinated crops.

INTRODUCTION

Heterosis has contributed significantly towards increased crop production and it has become the basis of multibillion dollar agro-businesses in the world (Phillips, 1999). Hybridization is the important way that can create genetic variability and make new options. The F1 population is obtained from the crossing of two homozygous but genetically dissimilar gametes or individuals (purelines in self pollinated crops or inbred lines in cross pollinated crops) that shows increased or decreased vigour over the better or mid parent value. Heterosis is maximum in F1, generation which diminishes gradually in later generations. Hence, production of F₁, hybrid seeds of different flower crops is considered as the extreme focused area in floriculture industry.

INTRODUCTION

Heterosis has contributed significantly towards increased crop production and it has become the basis of multibillion dollar agro-businesses in the world (Phillips, 1999). Hybridization is the important way that can create genetic variability and make new options. The F₁ population is obtained from the crossing of two homozygous but genetically dissimilar gametes or individuals (purelines in self pollinated crops or inbred lines in cross pollinated crops) that shows increased or decreased vigour over the better or mid parent value. Heterosis is maximum in F₁, generation which diminishes gradually in later generations. Hence, production of F₁, hybrid seeds of different flower crops is considered as the extreme focused area in floriculture industry.

Production of F₁ hybrids in ornamental crops was carried out even before Shull’s classical theory of hybrid vigour which was reported in 1971 for the first time in plant breeding. Benary Seed Company in Germany released F₁ hybrid in begonia (Begonia semperflorens) in the name of Prima Donna in 1909 (Reimann-Philip, 1983). But that time it did not attract the attention of plant breeders. It was during Second World War in 1942, when flower breeders were attracted towards heterosis breeding and started systematic F₁ hybrids. From 1950 onwards, numerous outstanding hybrids have been developed in many other flower crops in several countries like USA, The Netherlands, Denmark, Germany, United Kingdom and Japan, etc. First hybrid in single geranium was produced in 1960, in other flower crops like antirrhinum, pansy, marigold and zinnia in 1965, ageratum in 1966, geranium double in 1970, dianthus, begonia, impatiens and portulaca in 1976-77, gerbera in 1980 and carnation in 1981. In the present scenario of developed floriculture industry, in many countries F₁, hybrids are available in a number of annual flowers like ageratum, antirrhinum, anemones, calceolaria, dianthus, hollyhock, gazania, marigold, flowering tobacco, pansy, portulaca, stock, wall flower, zinnia, etc.

As emasculation is having the maximum share in cost of hybrid seed production, researchers have found several techniques in different flower crops as the alternative of emasculation and that can help in reducing the cost of hybrid seed production. The list of techniques being utilized commercially in different flower crops (Janakiram, 2004) is as follows:

Hybrid vigour is used as a synonymous of heterosis. In 1910, the term heterosis was first used by Shull who defined this phenomenon as the stimulus of heterozygous, and in his word, it has been the “interpretation of increased vigour, size, fruitfulness, speed of development, resistance to insect-pests and diseases or to the climatic rigors of any kind manifested by the out breeding organism as compared with corresponding inbreds as a specific result of the unlikeliness in the constitution of uniting parental gametes”. This definition is often interpreted as not implying a genetic basis for heterosis, because the definition basically describes the phenotypes that result from the crossing of two different inbred lines. Generally, heterosis is manifested as an increase in vigour, size, growth rate, yield, or some other characteristics but in some cases, the hybrid may be inferior to the weaker parent. This also represents as heterosis (average heterosis), and if heterosis is estimated over the superior parent, such an estimate is sometimes referred to as heterobeltiosis, hence, authors feel “heterosis refers a biological phenomenon in which the F₁ population obtained by crossing of the two genetically dissimilar gametes or individual shows increased or decreased vigour over better parent or over the mid-parental value. Earlier, Power (1944)also suggested that the term heterosis should be used only when the hybrid is either superior or inferior to both the parents. Other situation should be regarded as partial or complete dominance. It can be easily explained with the help of Table 5.1.

Introduction

Flowers speak millions of unspoken words. Presenting a bouquet and making arrangements with flowers in most of the drawing rooms, offices, hotels and hospitals have become the style of the day in the fast – moving modern world where there is hardly any time for exchange of sweet memories. Since time immemorial, the importance of such a delicate creation of nature has always been appreciated. Tamil Nadu ranks first among the flower producing states of India, contributing 25% of the country’s flower production with an area of 31, 970 ha under flowers. Of this, around 700 ha are under protected cut flower cultivation. In Nilgiri district alone, it has an area of around 70 ha under protected cut flower production which is inclusive of around 11.2 ha of lilium.

The genus Lilium (Lilium spp.) is a herbaceous flowering plant normally grown from bulbs, about 110 species world over belongs to lily family Liliaceae. It is native of the northern temperate regions. The species in this genus are the true lilies while the other plants with lily in the common name are related to the other groups of plants. Lilies are usually erect leafy stemmed herbs. The majority of species form tunicless scaly underground bulbs from which they produce flowers. The large flowers have three petals along with three sepals, look like petals.

Introduction

Rose, acclaimed as the “Queen of Flowers”, is one of the most popular cut flowers in the global floriculture trade. Popularly referred to as ‘Dutch rose’ in the international market, cut rose occupies a prominent place among the cut flowers owing to its exquisite form, size and attractive colours. Apart from cut flower it is used for making various value added products such as rose oil, rose water, garland, gulkhand, rose attar etc and also in landscaping as pot plant and garden plant. The present day rose (Rosa hybrida) combines all desirable qualities such as, productivity, attractiveness of buds, a variety of colours and forms of the typical species of Rosa.

The major cut rose producing countries of the world are the Netherlands, Colombia, Kenya, Israel, Italy, United States, and Japan. In India, roses are mostly grown under cover (poly house) in Nasik, Pune, Hosur, Kalimpong, Darjeeling, Bangalore, Solan, Palampur, Shimla, Srinagar, Delhi, Ludhiana and Calcutta. The roses grown for export should be popular varieties of that region and maintain high quality standards with respect to bud size and stem length and should have lush green leaves and be free of pests and diseases. These high quality standards can be achieved and maintained only when grown inside poly house or greenhouse, which gives protection against inclement weather conditions and pests and diseases.

Malvaceae, the mallow family, carries herbs, shrubs or trees comprising about 75 genera and perhaps as many as 1,500 species. Hibiscus and Abelmoschus are two important genuses under this plant family. Several species of plants of potential uses come under these two genera about which limited publications are available. 

Hibiscus

Hibiscus is a large genus of about 200-220 species of flowering plants in  Malvaceae, native to warm temperate, subtropical and tropical regions throughout the world. The genus includes both annual and perennial herbaceous plants and woody shrubs and small trees. The leaves are alternate, simple, ovate to lanceolate, often with a toothed or lobed margin. The flowers are large, conspicuous, trumpet-shaped, with five petals, ranging from white to pink, red, purple or yellow, and from 4-15 cm broad. The fruit is a dry five-lobed capsule, containing several seeds in each lobe, which are released when the capsule splits open at maturity.

Hibiscus a well known member of the family Malvaceae, grows as an evergreen shrub plant. The plant is extensively cultivated as an ornamental plant that bears large flowers on the bushy hedges. These enormous flowers are usually dark red in colour and are not usually fragrant. The huge size and the reddish colour and hues attract humming birds (Kumar and Singh, 2012). The generic name is derived from the Greek word “hibiskos” which was the name Pedanius Dioscorides gave to Althaea officinalis. Hibiscus rosa-sinensis was named by Carolus Linnaeus. The Latin term “rosa-sinensis” literally means “rose of China”, though it is not closely related to the true roses. Member species are often noted for their showy flowers and are commonly known simply as hibiscus, or less widely known as rose mallow. The hibiscus is used as an offering to goddess Kali and Lord Ganesha in Hindu worship. Hibiscus is an important flowering and garden plant. It has various medicinal values (Chopra et al., 1996 and Sayed et al., 2012).

Hibiscus a well known member of the family Malvaceae, grows as an evergreen shrub plant. The plant is extensively cultivated as an ornamental plant that bears large flowers on the bushy hedges. These enormous flowers are usually dark red in colour and are not usually fragrant. The huge size and the reddish colour and hues attract humming birds (Kumar and Singh, 2012). The generic name is derived from the Greek word “hibiskos” which was the name Pedanius Dioscorides gave to Althaea officinalis. Hibiscus rosa-sinensis was named by Carolus Linnaeus. The Latin term “rosa-sinensis” literally means “rose of China”, though it is not closely related to the true roses. Member species are often noted for their showy flowers and are commonly known simply as hibiscus, or less widely known as rose mallow. The hibiscus is used as an offering to goddess Kali and Lord Ganesha in Hindu worship. Hibiscus is an important flowering and garden plant. It has various medicinal values (Chopra et al., 1996 and Sayed et al., 2012).

ORIGIN AND DISTRIBUTION

The ancestors of the modern exotic hibiscus were originally native to Mauritius, Madagascar, Fiji, Hawaii, China and India. Ornamentally most important species is Hibiscus rosa-sinensis. There is no known record of the history of the domestication of Hibiscus rosa-sinensis. In one view it is believed that the species is a native to China and was first cultivated by the Chinese for its showy flowers (Kimbrough, 1997). No extant wild populations of the species have however, been reported from that country. Another view holds that the species is a native of the South Indian Ocean islands of which Madagascar, the Mascarene Islands and the Rodriguez Islands are a part (Borssum Waalkes, 1966). This view is strengthened by the fact that three Hibiscus species genetically compatible with H. rosa-sinensis are native to this area (Singh and Khoshoo, 1989). It is thought that the species was collected and domesticated on these islands by far easterner during their westward migration.

Abstract: Ornamental hibiscus (shoe flower) is native of Asia, probably China, but now conspicuous in all warm countries. Hibiscus is cross pollinating, evergreen shrub and progeny can segregate widely for traits due to heterozygosity. High polyploid constitution of species predominant vegetative reproduction and rampant hybridization irrespective of chromosome number are features of this crop. The important traits for continuous crop improvement include plant with good growth habit, floriferous nature, desirable flower colour, size, shape and good keeping quality. A variety of flower forms, flower colours and growth forms exist. Very little genetic information and trait heritability has been established for this crop. Use of somatic hybridization, mutation breeding and marker assisted breeding are discussed. The continuous use of these techniques will ensure creation of new phenotypes for the market.

Hibiscus (Hibiscus rosa-sinensis) is a vigorous tropical evergreen flowering shrub valued for its large, colourful and attractive blooms. In India, its flowers are widely used for religious offerings, particularly in temple worship, as well as for ornamental and loose flower purposes. The chapter introduces its origin, distribution, genetics, botanical characteristics and important varieties. It also highlights the crop’s medicinal and food-related importance, including the use of hibiscus products in herbal beverages and processed foods. Detailed production practices cover climate, soil, propagation, field preparation, nutrient management, irrigation and cultural operations. Major pests and diseases, harvesting, postharvest management and yield are also included for commercial cultivation.

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.

With the culmination of green revolution, the yield in agriculture is almost static with the use of even great deal of inputs and resources with appearing decadence in nature. The agriculture, if continuous on with same trend, will no longer productive and sustainable. Heterogenity being vested with best survival and sustenance, attempt is underway towards crop diversification deploying remunerative crops and techniques so as to keep pace with rising demand of mankind. Added to this, dwindling land : man ratio (0.13 ha during 1990s), harvesting more return from a unit area of land, disguised unemployment, improper availability of fruits and vegetables (40 g and 120 g respectively as against 120 g and 280 g for fruits and vegetables, respectively), generating employment (143 man-days/ha in cereals, 860 man-days/ha in fruit production and 1000-2500 man-days/ha in cultural intensive fruit crops), are major concerns for high density planting (HDP). It is a holistic production system which helps in promoting and preserving dynamic agro-ecosystem. HDP is also an aid to biodiversity, biological cycles and organic farming. As an alternative to raise production and productivity especially to compete global trade, HDP is worth adoption.

India is regarded as a horticulture paradise due to growing of tropical, subtropical and temperate fruit crops in varied soil and climatic conditions. However, increasing pressure on land owing to diversion of orchard lands to various other obvious reasons as well as rising energy and land-costs, together with mounting demand for fruits have made HDP imperative to achieve higher productivity from limited space.

There is a shift in farmers’ perception from production to productivity and profitability, which can be achieved through high density planting. India is the second largest producer of fruits in the world. However, the average productivity of various fruit crops in the country is quite less. Low productivity can be attributed to many reasons such as old and senile orchards, lack of canopy management practices, planting of poor yielding varieties, low or no adoption of recommended package of practices by the farmer leading to poor orchard management, etc.

• Harmony is the principle of landscaping.

• Texture is an important element of landscaping.

• Blue is a primary colour.

• Green in a secondary colour.

• Garden furniture is a tangible item.

Social civilization of the Neolithic settlements of primitive human communities contributes substantial initiation of cultivation and an approach towards conservation of useful plant species for sustainable food habits. Several archaeological attestations confirm that Homo sapiens at the end of the Paleolithic period had knowledge on many useful plants derived from food gathering techniques. Growth of human populations beyond the size that hardly supports hunting and gathering for food materials may perhaps be the probable reason that forced the Neolithic primitive nomadic communities for settlement and emergence of crude forms of cultivation.

Introduction

‘Protected cultivation’ is a method of cultivation of plants or crops in artificial environment (Polyhouse/ Greenhouse/Glasshouse) to protect the plants or crops from the natural calamities viz. wind, hailstorm, excessive radiation, temperature extremes, insect-pests and diseases. For matching ever growing needs of human population in the country, it has become imperative to provide the not just cereals but also fruits, vegetables, flowers and other horticultural products to fulfill their requirements. In the present scenario of perpetual demand of horticultural produce in order to increase their production round the year and shrinking landholdings drastically, protected cultivation is the best alternative and drugery- less approach for using land and other resources more effeciently.Protected cultivation comprised of selection of crop and media, climate control,marketing, post harvest technology, plant protection and irrigation/ fertigation.

In India, states like Karnataka, Andra Pradesh, Maharashtra and Tamil Nadu are the best suited for protected cultivation of horticultural crops due to their pleasent climatic conditions. Apart from these states, Himachal Pradesh, Uttar Pradesh, Jammu and Kashmir, West Bengal, Delhi and Jharkhand are also fore runners in adopting protected cultivation. Protected cultivation is a key for sustainable production in the country due to its various ecological regions viz., Western Himalayan region, North eastern Himalayas, Eastern Plateau hill regions, Central Plateau hill regions, Western Plateau hill regions, Southern Plateau hill zone, East coast hill zone, West coast hill regions and Gujarat hill regions (Gupta et al., 2003). Control of light through polycover has become a significant part of horticulture technology because quality, intensity and duration of light is involved in many physiological processes of the plants. A plastic film or fibre glass covering over a green house acts like selective radiation filter which allows solar radiation to pass through but traps radiation emitted by the plants inside the greenhouse which is known as ‘Greenhouse effect’. Carbon dioxide released by the plants at night also trapped, this raises the level of CO₂ there by enhances the photosynthetic activity (Ahmed, 1996).

Growing of flowers in gardens was patronized by the rulers themselves earlier. Commercial production of flowers gathered momentum globally, efforts to breed new varieties of flower crops intensified in the 70s, and 80s primarily due to their high commercial value. With the advent of WTO followed by the Plant Breeder’s Rights, the commercial breeding efforts got intensified further. Domestication, introduction, selection, hybridization, mutation, and polyploidy breeding have played a major role in the evolution of the present day ornamental plants.

4.1 Brief historical account

Flowers have long been associated with each civilization and culture in the world. Numerous cultures have incorporated flowers into their everyday lives expressions of beauty and art. Flowers are used to celebrate major life events and to decorate graves, expressing emotions in ways that words are deficient.

In the beginning, human kind selected some of the useful wild flowers and brought them into gardens for domestication. They were used for their floral and other values. According to Theophrastus (372-287 BC), carnation was grown in Greece during 300 BC. It was used for medicinal purpose in France. Romans prepared dye from calendula flowers. During early days, Bells of Ireland (Moluccella laevis) was used as a vegetable, but now after much improvement, it is used as a cut flower. The rose, which is an important flower today, has long history, perhaps older than man. Orchids were known for their attractive appearance and fragrance in China about 2500 years ago as mentioned by Confucius. Man’s interest in cultivating and growing orchids developed during the 19^th century in Europe. Chrysanthemum is the one of the oldest flower grown in China as early as 500 BC. Most of garden flowers were introduced into Europe from their wild habitats between 16^th and 19^th century. Ornamental annuals constitute an amazing group of plants widely grown in the parks and gardens in different seasons. The enchanting beauty of colour, shades, form and fragrance have made them an obvious choice for every garden. No other plant can influence the general landscape in such an incredible manner by riot of colours.

Bioinformatics encompases the use of tools and techniques from three separate disciplines; molecular biology (the source of the data to be analyzed), computer science (supplies the hardware for running analysis and the networks to communicate the results), and the data analysis algorithms, which strictly define bioinformatics. So the list below incorporates events from these areas into a brief history of the field.