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Dahlia (Dahlia variabilis) belongs to the family Compositae and is a native of Mexico. Modern garden Dahlias with large blooms in wide array of colours are important flowering plant for Indian gardens. The range of forms, size and colours of the flowers is simply amazing. In the plains of India, Dahlias produce flower during winter season and usually grown as potted plants for display purpose. At suitable sunny locations, they are planted in beds also.

Classification

There is enormous variation in shape, size and flower colour of Dahlia. In addition, hundreds of cultivars are available for use in the garden. For having information on various groups having different flower structure, size etc., it is important to know classification. Garden Dahlias have been classified in the following major categories (based on the National Dahlia Society, United Kingdom).

Anemone - Flowers double having one or more rows of petals; disc florets tubular; ideal as cut flower for floral arrangement.

Ball - Flower head in ball-shape, fully double; petal tips ovate or round and rolled half length. There are large variation in the size of flower head and categorization.

INTRODUCTION

In the world of flower, together with lilies, gladioli, begonias; the dahlias are one of the most important and popular flowering bulbs. With the blast of different colours, shape and sizes, dahlias bring life and beauty back to the landscape in late summer and autumn. The diversity of dahlias allows their usage in many different aspects due to huge range of flower types available and fairly easy cultivation.

In modern garden, dahlias are extensively used for exhibition, garden display and decoration. It can be grown in any form in the garden; in beds, in borders or even in mixed borders alongwith other plants. It grows well in pots also. For border purpose dwarf growing type are preferred while in pots usually large flowering dahlias are grown. The long stemmed flowers of various forms and colours are used in flower arrangement. Dahlias make excellent cut flowers, which typically last about a week in the house and are also used in making garlands.

The tubers of dahlias contain appreciable amount of insulin and fructose and small quantities of phytin and benzoic acid which are of medicinal and nutritional value. Flavanone 3-hydroxylase, which catalyses the conversion of flavanones to dihydro flavonols, was detected in flower extracts of cyanic strains of dahlia.

Introduction

In modern garden, dahlias are extensively used for exhibition, garden display and decoration. It can be grown in any form in the garden; in beds, in borders or even in mixed borders along with other plants. It grows well in pot also. For border purpose dwarf growing type are preferred, while in pots usually large flowering dahlias are grown. The long stemmed flowers of various forms and colours are used in flower arrangement. Dahlias make excellent cut flowers, which typically last about a week in the house and are also used in making garlands.

The tubers of dahlias contain appreciable amount of insulin and fructose and small quantities of phytin and benzoic acid which are of medicinal and nutritional value.

Introduction
Among flowers, the rose enjoys the greatest adorable position over the world. In real sense, rose almost hypnotised the man most by its colour and fragrance. Apart from its aesthetic value, the roses are of high economic benefits, and religious significant. Besides, it finds it place in art and culture from times immemorial. The rose thus merits pride of place as the ‘Queen of flowers’.
Origin
The damask rose is originated in ancient Persia (now Iran), and later on spreading over Europe and Northern Africa. Further, widespread farming of R. damascena for rose oil manufacturing began in Turkey and Bulgaria. Many countries of the world grow scented roses for extraction of the volatile essential oil. The genus Rosa grows wild in many parts of the temperate and sub-temperate regions. The major growing countries are Bulgaria, France, Italy, Turkey, Russia, China and India. Bulgaria is the principle European country for supply of rose oil to the world market. Among different species, Rosa centifolia Linn. is largely grown in France and Italy, whereas Rosa
damascena Mill. in Turkey, Bulgaria, Russia and Persia. Rosa damascena Mill. was first introduced successfully in middle east countries during 1680, resulting in the establishment of entire area as ‘Valley of flowers’. It belongs to family rosaceae.

Introduction
Davana (Artemisia pallens Wall.) is one of the important aromatic herb found abundantly in humid habitats in the plains all over India. It is popularly known as sage brush, worm wood and mug word. The davana (Artemisia pallens) is a small to medium height; annual and herbaceous aromatic plant. This herb is erect, and grow up to 60 cm height. Its leaves are highly divided and bears small size yellow coloured flower. Its leaves and stem found protected with greyish-white tomentum. The leaves are lobed, alternate, and petiolate.
Origin & Distribution
It is native to southern India, where it is traditionally grown in Karnataka, Maharashtra, Kerala, T.N., and A.P, growing widely in tropical to subtropical
plains as Rabi season crop. It also found growing in wild form in the Himalayan region in the Simla, Kashmir valley, and Nainital hills. It is widely used by Ayurvedic healers to balance the three energies. It is an erect growing
plant up to 60 cm height. It does not grow wild, but grown as a garden plant in South India. It is a crop of irrigated conditions; and do well when planted in November-December, yielding significantly higher oil yield in comparison to crop planting in July-August. The crop should be harvested 2-3 inches above ground level during bright sunny days at 50 percent flowering stage to have high oil content and oil yield.

Flowers and various parts of the plant have been used for decoration and to commemorate various religious, festive, matrimonial and social gathering events in day to day life. The main drawback of fresh flowers and foliage is being highly perishable and delicate which cannot retain their beauty for longer durations. Moreover fresh flowers are not available round the year which can be overcome by the dehydration and drying techniques. Since ancient times, in Egyptian pyramids, fragrant dried flowers and herb garlands were encased along with mummified bodies. Japanese people created “Oshibana”, the “preserved flower art” of enduring designs to retain the exquisite beauty of the living plants centuries ago.

Later on, this craft making technique spread from Japanese to Victorian England because of their beautiful long lasting appearance. During middle ages monks dried flowers, foliage, and herbs for use in decorative motifs or for colouring their handprinted books.

Dried flower arrangements have been popular in Europe for centuries, and as early as 1700 AD, colonial Americans used dried flowers to brighten their homes, especially during the dark winter months.

Earlier botanists practiced dried flowers in the form of herbarium for the purpose of identification of various plant species. Though drying of flower was well known even in the past but for the first time the flowers were dried commercially in Germany (Sankari and Anand, 2014).

48.1. Aim

To conduct practical on drying of fruits

48.2. Theory

Drying generally refers to the method of removal of moisture from the food under natural condition such as sunlight and wind for example open sun drying, shade drying etc. Dehydration refers to a process of removal of moisture by application of artificial heat under controlled conditions of temperatures humidity and air flow. It also represents drying of agricultural commodity to dry state. For drying, single thin layer of fruit and vegetables, either whole or sliced after primary pre-treatments is spread on the trays which are then placed inside the dehydrator or in the open sun for drying. In the dehydrator initial temperature is generally kept at 43oC which is then gradually increased to 66-71oC for fruits.

49.1. Aim

To perform practical on drying/dehydration of different vegetables.

49.2. Theory

Drying refers to the method of removal of moisture content from the food to a level at which the activities of food spoilage and food poisoning micro-organism are inhibited. Therefore, reduction in water activity of the food is the main principal of preservation by drying. In the dehydrator initial temperature is generally kept at 43oC which is then gradually increased to 60-66oC for vegetables. The product shall be prepared from wholesome vegetables free from blight, insect infestation and fungal discoloration. Only edible portion of the vegetables shall be used and it shall be free from stalks, peels, stems, and extraneous matter. The dried/dehydrated vegetable may contain permitted preservative. The finished product shall be of good edible quality and shall reasonably reconstitute to its original shape and quality on boiling for 15 minutes to an hour. The finished product shall be free from visible mould, insect or larvae. Kind of dry vegetable shall be declared on the label. Acid insoluble ash shall not be more than 0.5%.

Demand-driven vegetable breeding emphasizes the development of new cultivars based on specific consumer preferences, market demands, and environmental conditions. This approach contrasts with traditional breeding methods that primarily focus on agronomic traits like yield or disease resistance. The importance of demand-driven breeding lies in its ability to align agricultural production with consumer needs and market trends. By directly responding to consumer preferences such as taste, appearance, nutritional content, and culinary characteristics, breeders can create vegetables that are not only commercially viable but also meet consumer expectations. This approach enhances market acceptance and profitability for growers, distributors, and retailers alike. Breeders prioritize demand-driven breeding to stay competitive in a rapidly evolving market where consumer preferences can shift quickly. By understanding and responding to these preferences, breeders can develop cultivars that offer distinct advantages over existing varieties, leading to increased market share and improved economic outcomes for stakeholders throughout the supply chain. This chapter provides an understanding on demand-driven vegetable breeding, particularly opportunities, and challenges.

Dendrobium is a huge genus of orchids. It was established by Olof Swartz in 1799. The name is from the Greek word “Dendron” means “tree” and “bios” means “life”; it means “one who lives on trees”, or essentially, “epiphyte”. The truly spectacular genus Dendrobium contains the largest diversity of horticulturally interesting specimens. More than 1,000 natural species make dendrobium the second-largest orchid genus. Dendrobiums are among the most commonly encountered orchids in the retail trade. Flowers are very long-lasting both on the plant and once cut, looking fresh for up to three weeks or more. Faded flowers on the bottom of the stem can be removed to encourage upper buds to open. Dendrobiums are sturdy orchids that can add a focal point to any room.

ORIGIN AND DISTRIBUTION

Dendrobiums are originally from Southeast Asia. The geographic distribution is from India through China, Japan, Malaysia, Philippines and the islands of the South Pacific with the largest diversity in New Guinea. Dendrobium species are either epiphytic or occasionally lithophytic. They have adapted to a wide variety of habitats from the high altitudes in the Himalayan mountains to lowland tropical forests and even to the dry climate of the Australian desert.

Sustainable development and efficient management of water is an increasingly complex challenge in India. Increasing population, growing urbanization and rapid industrialization combined with the need for raising agricultural production generates competing claims for water. Ground water has an important role in meeting the water requirements of agriculture, industrial and domestic sectors in India. About 85 percent of India’s rural domestic water requirements, 50 percent of its urban water requirements and more than 50 percent of its irrigation requirements are being met from ground water resources. Ground water is annually replenishable resource but its availability is non-uniform in space and time. Technically, the dynamic ground water refers to the quantity of ground water available in the zone of water level fluctuation, which is replenished annually. Hence, the sustainable development of ground water resources warrants precise quantitative assessment based on reasonably valid scientific principles. National Water Policy, 2012 has laid emphasis on periodic assessment of ground water resources on scientific basis. The trends in water availability due to various factors including climate change must also be assessed and accounted for during water resources planning. To meet the increasing demands of water, it advocates direct use of rainfall, desalination and avoidance of inadvertent evapo-transpiration for augmenting utilizable water resources. The National Water Policy, 2012 also states that safe water for drinking and sanitation should be considered as pre-emptive needs followed by high priority allocation for other domestic needs (including needs of animals), achieving food security, supporting sustenance agriculture and minimum eco-system needs. Available water, after meeting the above needs should be allocated in a manner to promote its conservation and efficient use.

1. Introduction

The Indian economy is heavily dependent on agriculture (employing 53 % population). Around 84 % of the holdings are less than 2 ha while approximately 67% of the farms have less than 1 ha of operational farmland (Government of India, 2013; Pandey and Suganthi, 2015). A large fraction of the farming population is mostly reliant on monsoon rains for irrigation. The condition of the farmers is found to be deteriorating year after year with the revelation that 27% of farmers did not consider farming as a profitable enterprise and 40% were ready to migrate to other avenues for employment (NSSO, 2005; Pandey and Suganthi, 2015). 

Introduction

Flowering plants (Angiosperms) are identified by their morphological characteristics like flower, fruit and seeds that help their taxonomic characterization into different species, genera, families and orders. The floral characters which are used for taxonomic characterization of plants include the type of inflorescences, perianth structure, floral symmetry, arrangement of floral leaves, type of androecium, stamens, gynoecium, carpel, ovule, etc. The type of fruit and seed also play important roles in taxonomic classification. In this chapter we will briefly discuss about various morphological features of flowering plants (in botanical terms) that are useful in taxonomy.

Nomenclature of Plant

Nomenclature of plant is the formal and scientific naming of plants. It is related to but distinct from taxonomy for grouping and classifying plants and provide botanical name.

The scientific/botanical nomenclature started with Species Plantarum by Carolus Linnaeus in 1753. Botanical nomenclature is governed by the International Code of Nomenclature for algae, fungi, and plants (ICN), which replaces the International Code of Botanical Nomenclature (ICBN).

ICBN and ICN

International Code of Botanical Nomenclature, (ICBN) was adopted by the VIIth International Botanical Congress held in Stockholm, July1950. While the International Code of Nomenclature for algae, fungi, and plants (ICN) was adopted by the XVIIIth International Botanical Congress held in Melbourne, Australia in July 2011.

Moniliformis means ‘like a string of beads’ signifying the arrangement of flowers on the spike. The tree is native of tropical Australia. It is valued for afforestation and beautification. It grows in warm climate under both dry and moist atmosphere. It is a medium-sized, thornless, quick growing, evergreen tree of 13 to 15 m height.

Leaves: True leaves are present only in early seedling stage. The apparent leaves are the modified midrib called phyllode, leathery, sickle-shaped, tapered at each end, up to 18 cm long and 6 cm broad; nerves parallel.

Annuals are the group of plants that complete their life cycle in one season or in one year during which they grow, flower and produce seed; and after this they wither out. A true annual (like zinnia) is a plant that will grow from seeds, flower, produce seeds and die in one season. Zinnias provide a succession of flowers for summer colour in any sunny location with good soil drainage.

Greenhouse refers to a structure which provide relatively better environment for plant growth. The goal is to create congenial temperature and relative humidity in desired range. The greenhouse covered with polythene sheet, also called as polyhouse, has polythene sheet (UV stabilized 200 micron LDPE sheet) as covering over a relatively rigid frame (made of GI pipes, angle iron, boomboo or wooden) which entraps the solar energy to increase the temperature and provide light for plant propagation. A normal greenhouse has four basic components: 1) frame made from rigid material like GI pipes, wood or bamboo; 2) glazing material, which is transparent to provide enough light for plant propagation; 3) climate control system, which may be natural ventilation or forced ventilation using fans with or without cooling pads, shading nets, pigment painting, etc. and 4) plant growing medium (soil or artificial media like cocopeats) with needful arrangement for supplying inputs (water, fertilizers, pesticides, etc.). The design of greenhouse involves structural design of frame with enough climate control mechanism. It mainly depends on shape, size, material of frame, local climatic conditions, wind pressure, and desired height from crop production point of view. Fabrication of greenhouse should be such that it provides enough structural stability with wind pressure and other factors, perfect joints, anchoring of polythene, and minimum hindrances in crop production practices.

4.1 Introduction

Experts predict that the global population will exceed 9.6 billion by 2050. This, coupled with the rise of urbanization, the scarcity of arable land, and the destructive effects of climate change, poses significant challenges for agriculture and food production worldwide. To combat these challenges, new horticultural research techniques must be implemented to enhance productivity and efficiency, improve nutrition, and ensure food security, especially during times of crisis like the COVID-19 pandemic. Greenhouse technology has made remarkable strides in recent years, allowing for the manipulation of internal growth elements like temperature, light intensity, and CO2 concentration to create optimal growing conditions

P rotected cultivation technology envisages immense promise, especially for high-value crops against various biotic and abiotic stresses. The climatic parameters stress conditions like unusually low and high temperature, humidity, solar radiation, wind velocity comes under abiotic stresses. The present climate change scenario dealing with various biotic and abiotic stress conditions poses serious threat to agricultural production throughout the world. It is estimated that due to one-degree rise in temperature during rabi season, wheat production declines by 4-5 million tonnes in India. Similarly due to prevailing low temperature and frost like conditions, especially in Northern India, several million tonnes of horticultural crops like tomato, brinjal etc. got wasted every year. Protected cultivation technology deals with following types of protected structures :

A greenhouse with all measures of climate control is one important component for integrated greenhouse crop production and protection. However, the growing period is very often limited to few months in the year, because of insufficient ventilation and cooling in summer as well as heating in winter. Structures and shapes of greenhouses are adapted insufficiently to climate conditions. Climate control and greenhouse structures have to be adapted and optimized with regard to outside climate, and growers must be trained in these adapted technologies. A greenhouse structure with light transmittance (through framework and cladding material), ventilation, heating, cooling, and protection from insect pests by screening, as well as all influences of management, irrigation, fertilization, water quality, physical and biological plant protection is an integrated system. Greenhouse structures should be designed according to the climate conditions and to the general design criteria, as well as to the locally available and cost-effective materials. The import of greenhouses from countries with a different climate fails very often, because they are not adapted to the local conditions. Even an appropriate greenhouse structure can fail if mounting and continuous maintenance are not guaranteed. Temperatures and global radiation allow open-air crop production throughout the year in many subtropical and tropical countries.

Vegetable and flower production are significantly influenced by the seasonality and weather conditions. The extent of their production causes considerable fluctuations in the prices and quality of vegetables. Striking a balance between all-season availability of vegetables and flowers with minimum environmental impact, and still to remain competitive, is a major challenge for the implementation of modern technology of crop production.

Every garden has got specific purpose and utility. Specialized gardens are planned gardens according to various locations and fulfilling specific needs. Therefore, these should be designed envisaging primary requirements depending upon the types. Features of these are specific including plants and planting pattern. So, these gardens need to be dealt separately so that planning and execution is done in more systematic way focusing utilitarian and ornamental purposes.

Home Garden

Basically it is a piece of land attached to the home, beautified with different features, ornamental and flowering plants. The main purpose of this type of garden is beautification round the year and utility for relaxation of the family. Accordingly, design and features should be selected to fulfill the same.