eChapters

Abstract: Gaillardia, commonly known as ‘Blanket flower’, is excellent for cut flower, mixed borders, edging and bedding plants. Huge quantum of variability exists in this crop in India. Currently, there are many interspecific hybrid cultivars and open pollinated varieties available in the market. Biparental inbreeding depression has complicated the progress of crop development. Traits of interest to flower breeders for crop transformation include, plant architecture, flower morphology (colour, size, quality), attractive seed heads and drought stress.

Abtract: Dahlia, tuberous flowering plant, is valued for potted flowering and garden crop worldwide. The genus contains ~85 species native to Mexico, central America and Columbia. Numerous phenotypes (star/ anemone/ paeony/ decorative/ pompon/ cactus/ water lily flowered) and cultivars (giant/ large/ small/ miniature/ ball/ pompon/ mignon single) are available on world market. Cultivated dahlias are allotetraploids with great diversity in flower colour/ forms. Limited genetic information and trait heritability has been established for this crop. Precise elucidation of the genes involved in the flavonoid biosynthesis pathway has enabled in the creation of new flower colours or modification of pigment production and expression discussed. Research succeeded in mutation breeding and interspecific hybridization and colourful dahlia varieties have been developed by individual enthusiasts, nurserymen and flower breeders. Complicated genetics, heterozygosity often pose significant challenges to breeders. Future crop ideotypes are proposed to continue transformation of this important crop during the next millennium.

Abstract: Crossandra, traditional flower crop of India, produce beautiful flowers in remarkable range of colours of almost all the year. Flowers are ideal for garland making and hair adornments. Only few species are cultivated across the world. Improvement is focused on drought tolerant ornamental types for landscape/ container use, better keeping quality, heavy yield and vivid range of flower colours, long spikes, earliness and big flower size. Breeders have created mutant cultivars and F₁ hybrids having valuable traits. Lack of fragrance and meager seed set require biotechnological interventions.

Abstract: Cosmos, popular as garden annual in many parts of the world, has its origin in Mexico. Cosmos is cross pollinating and progeny can segregate widely for traits due to heterozygosity. Self and cross incompatibility, self and intersterility, limited fertility, reproductive barriers and seed sterility often pose significant challenges to breeders. The breeding objectives include development of suitable indoor plants, less susceptible to powdery mildew and more tolerant to abiotic stress. The biotechnological skills can be attempted in breeding.

Keywords: Breeding, self incompatibility, sterility, hybrid seed production.

Abstract: Chrysanthemum, commonly known as Queen of East, is perhaps oldest flowering plant, commercially grown in different parts of the world in a wide range of floricultural product including potted plants, cut flowers and garden plant. Vast range of shapes and sizes of flowers, brilliance of colour tones, long lasting bloom, ease of production and cultivation all the year round, range of plant habits from pot mums to tall shrub, hardy nature, and versatility of use make this a versatile floriculture crop, wide range of polyploidy level (diploid to decaploid) is found in different cultivars and are almost exclusively asexually propagated. The crop arises from multiple species, its allopolyploid nature has complicated progress in crop development due to inbreeding depression, genetic load and aneuploidy. Precise genetic information and trait heritability has been established for this crop; plant breeding continues to produce new variants for commercial production. Currently, numerous varieties have been developed through complex interspecific crosses among elemental species, open pollination, indiscriminate Intervarietal hybridization, spontaneous and induced mutation, selection, and management of chimera. Number of traits targeted for genetic intervention have been presented and discussed. Crop idiotypes for product classes prescribe numerous traits for incorpotion by flower breeders and geneticists including compact framework to withstand bloom for pot mums, long lasting bloom colour with enhanced shelf life for cut flower and sweet scented blooms with extended blooming season for garland use.

Abstract: The most popular ornamental monotypic species chinensis, is an important annual flower, used commercially as cut flower for interior decoration, bedding, potting and landscape purpose. Currently, there are many interspecific hybrid cultivars from this species on the market. The influence of breeding methods on the selection criterion and selection procedures is discussed. Information on variability and correlation is included. Ample genetic information and trait heritability has been established for this crop. Traits of interest to flower breeders for crop transformation include plant architecture, flowering (colour, size, timings), attractive flower heads, extended bloom time, horizontal placement of flowers, floral longevity, earliness, healthy foliage or other morphological traits. Future crop ideotypes are proposed to continue transformation of this crop for large scale cultivation.

Abstract: Carnation, is one of the commercial flower crops of the world. There are many forms of carnations, which are excellent for cut flowers, bedding pots, edging and rock gardens. The history of crop improvement and development is highlighted. Their continued popularity has warranted extensive breeding and development of novel phenotypes particularly standards (Sims), sprays, midis, annual, picotees, perpetual, chabaud, malmaison, multiflora, microcarnations, etc. Continuous breeding and improvement of carnation focus on floral fragrance, floral doubleness, dwarf stature, high growth rate, floral colour, reduced calyx splitting, floral longevity and disease resistance. Ample genetic information and trait heritability has been established for this crop. Molecular genetics techniques are valuable tools aiding modern carnation breeders. Numerous genes have been identified and being used to create transformants. Wonderful results achieved through interspecific hybridization, mutation and polyploid breeding are discussed. Poor pollen production, inbreeding depression, linkage between traits, limited gene pool, inadequate seed production, reproductive barriers often pose significant challenges to breeders. Crop ideotypes prescribe numerous traits for incorporation by flower breeders and geneticists, including straight stem, symmetrical flower shape/ form, early/ uniform flowering with high productivity, enhanced shelf life and resistance to physiological disorders and various diseases.

Abstract: Zantedeschia, commonly known as calla lily, is one of the popular ornamental plant in the world. Zantedeschia are commonly associated with the New Zealand, even though they are native to South Africa. The vegetatively propagated crop is currently the most important rhizomatous geophyte in the world. Most cultivars are grown for cut flowers, variegated or spotted foliage for floral arrangements, flowering potted plants and landscaping. Continued breeding and improvement of Zantedeschia focused on disease resistance, improved floral longevity, novel spathe colour, better bloom quality, longer stems, more flowers/ rhizome and determinate growth habit. Intersectional/interspecific hybridization is hampered by post fertilization barriers, hybrid breakdown, albino hybrid embryo and F₁ sterility. Crossing barriers have been overcome with the use of in vitro embryo rescue. Haploidization and molecular techniques are being used to create homozygous plant and marker assisted selection, respectively.

Abstract: Bougainvilleas are morphologically diverse and admired for their ornamental value. The considerable diversity exists in bougainvillea species for leaf shape, degree of hairiness, bract colour, spine shape and blooming. These attributes have enabled the ornamental bougainvillea to be used as pot plants, hedge, pergola, standard and bonsai for display. Currently, there are many intra and interspecific hybrid cultivars and numerous mutations from numerous species in the market. Limited fertility, heterozygous nature, strong self incompatibility and seed sterility often pose significant challenge to breeders. Traits of interest to flower breeders for crop transformation include; plant architecture, flower timing, colour diversity, multibracts and multicolour in single variety, environmental adaptation to stressful condition (cold tolerance, heat tolerance, drought tolerance, etc.).

Abstract: Impatiens are popular seed and vegetatively propagated bedding plants with numerous series (Shadeglow, Firefly, Peach Ice, Circus, Hawaii, Pixie, Show Topper, Elfin, Shady Lady, Fanciful, Fantasia, Fiesta, Futura, Jewel, Minarette, etc.) and F₁ hybrid cultivars available on world market. The history of balsam development as a crop is highlighted. Continued domestication by flower breeders produced a wide range of flower colours and flower patterns. Ample genetic information and trait heritability has been established for this crop; plant breeding continues to produce new variants for commercial production. Continuous breeding and improvement of balsam focus on flower colour/ size/ pattern, double flowers, plant growth habit/ branching and disease resistance. Important traits for both production and landscape use include flower colour/ size and bloom time, larger flowers, resistance to biotic and abiotic stress and other valuable traits. Results achieved through interspecific hybridization and polyploid breeding are discussed. The chapter concludes with future prospective for research and breeding in the genus.

Abstract: Anthurium, popularly known as aristocrat of the plant world, is admired for its unique ornamental value. The Netherlands remains the world’s largest grower and primary source of new colours and cultivars to the international market; while Hawaii remains the epicenter for published research on various aspects of anthurium genetics, propagation and improvement. Flower breeders have created numerous genotypes during the millennia of breeding this crop, which has enabled its establishment as pot plant and cut flower industry. Continued breeding and improvement of anthurium focus on floral fragrance, disease resistance, new flower shapes/ colours and improved floral longevity. Wonderful results achieved through interspecific hybridization, multiway crosses, polyploidy breeding and molecular genetic techniques have been discussed. Cultivars are almost exclusively asexually propagated. Anthuriums are cross pollinating perennial shrubs and progeny can segregate widely for traits due to heterozygosity. Long life cycle of plants, slow seed formation and maturation, slow suckering often pose significant challenges to breeders. Biotechnology has created a new horizon in anthurium breeding. Increasing knowledge of the inheritance of traits and molecular genetics techniques are valuable tools aiding modern anthurium breeders. Future crop idiotype is proposed to continue transformation of this monocot aroid crop during the next millennium.

Hippeastrums, commonly known as Royal Dutch amaryllis/ Trumplet lily/ Belladonna lily, are bulbous ornamentals grown around the world for cut flowers, potted plants, window gardens and floral arrangements. The numerous hybrid phenotypes (miniature, orchid flowering, imbricated/ reginae, long trumpet/ belladonna type, etc.) are available in the world market. The history of its development and new trends of breeding are described as an aid for continued crop development. Tissue banks of cultivars are genetic evolutionary race history have been charted out for future improvement. Most cultivars are diploids and tetraploids cross incompatibility, sterility, reproductive barriers, self incompatibility often pose significant challenges to breeders. Little genetic information and trait heritability has been established for this crop, plant breeding continues to produce new variants for commercial production. The use of intra and interspecific hybridization, breeding for specific traits, polyploidy and mutation breeding are presented with a focus on creating novel transformations for this crop in the future.

An understanding of intellectual property rights for plant breeders has become increasingly important over the last few decades. It is also a confusing topic to many in the industry. Confusion is understandable when we are presented with various types of protection, many acronyms, terms used interchangeably and incorrectly, regulations that vary internationally and a lack of understanding or consistent interpretations of laws that govern these rights.

Plants are unique from other marketed products due to their complex nomenclature, ease of propagation and the many levels of distribution and promotion involved in their marketing. The protection is required for a plant cultivar needs to be considered in relation to all of these factors in order to be correctly implemented and maintained. Breeding and commercialization of new ornamental plant varieties is an economically important activity both for the industry and the well being of our society. Breeding or developing a new variety requires a long time. In horticultural crops, it takes 3-10 years from initial crossing of parent cultivars to develop a commercial variety. It is important to encourage development of new variety by providing incentives such as Plant Breeders’ Rights (PBR) over exclusive production and marketing of seed of an improved variety. When the new cultivar is introduced and commercialized, plant breeders finally begin to get paid for their years of hard work in the form of royalties. Legal protection for new plant varieties provides the means by which companies, institutions, and independent plant breeders can receive a return on their investments of time and money as well as justify their involvement in research and new plant development. In addition, legal protection enables plant breeders to be recognized for their craft and skill and encourages plant breeding as a profession. Plant variety protection provides an incentive for continued breeding and to ensure the availability of new varieties that meet future demands and keep the industry thriving.

Like in other crops, international research centres can contribute substantially towards solving the problems that limit ornamentals production because several research constraints are global in nature and need the research support by well staffed and adequately equipped research centres, which can make the work of national research programmes more efficient and accelerate the development of solutions. These international research centres can build a critical mass of scientists that is very important for effective research. It has almost established that successful research in individual crops has usually required the team efforts of specialists working in a range of disciplines like genetics, breeding, agronomy, physiology, pathology, entomology, economics, soils, statistics and chemistry, etc. These research centres are required to 1) Serve as catalyst for change 2) Collect, evaluate, maintain and utilize germplasm, 3) Generate and disseminate information 4) Provide training 5) Stimulate the formation of critical mass for research and 6) Assist national programmes achieving desired goals faster and more efficiently.

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.

Flowers are classified into three groups- self pollinated, often cross pollinated and cross pollinated- based on the extent of cross pollination which ranges from nil to 5 percent in self pollinated, 5-12 percent in often cross-pollinated and more than 12 percent in cross pollinated flowers. The information on extent of cross pollination is important to decide appropriate breeding methods to develop and improve the crop, to maintain genetic purity of seed, and to decide safe isolation distances from varieties, related species and related genera of the crop.

3.1 Autogamous (Self pollinated) flowers

When the egg in a flower gets fertilized by its own pollen, it is, referred to as autogamy. In statistical terms, it is, explained as the probability that egg gets fertilized by its own pollen as one. The coefficient of inbreeding which also measures the probability of selfing is also one in such crops. The genetic structure of autogamous flower is homozygous. The reasons for autogamy in flowers are essentially homomorphism, cleistogamy and chasmogamy. Homomorphism refers to uniformity in placement of essential floral parts, androecium and gynoecium e.g. Aster (double flowered), Balsam, Bells of Ireland, Carnation, Clianthus, Benghal dayflower (Commelina benghalensis), Gypsophila, Lupine, Salvia, Saponaria, Sweet pea and Sweet William. In autogamous ornamental crops, cross pollination in nature is almost negligible. Autogamous pollination may be of three types viz., autogamous selfing: refers to origin of pollen from anthers of the same flower; geitonogamous selfing refers to pollen from different flower on the same shoot or genet, and xenogamy, crossing refers to pollen from different flower on a shoot from another genet.

The concept of Centers of Origin given by Russian scientist N.I. Vavilov (1935) is based on his studies of vast collection of plants at the Institute of Plant Industry, Leningrad. According to him, crop plants evolved from wild species in the areas showing great diversity and termed them as primary Centers of Origin; but in some areas, certain crop species show considerable diversity of forms although they did not originate their, such areas are known as secondary Centers of Origin of these species. He identified 8 primary centers (Chinese, Indian, Inner Asiatic, Asia Minor, Mediterranean, Abyssinian, South Mexico, Central America and South America Andes Center) and three sub-centers (Indo-Malayan, Chilean and Brazilian-Paraguayan sub-center) of origin for crop plants. Basilevskaya (1960) first investigated the geographical origin of garden plants. Coats (1968) first stressed out the ornamental herbs whereas Hui-Lin-Li (1974) wrote about the introduction of woody plants. According to Tay (2007) survey of thirty common flowers and their related species show a similar pattern of concentrated occurrence of species in certain geographic regions.

Exploration and exploitation of gene centers need to be proceed with the systematic cooperation of taxonomists, geneticists and plant pathologists. The 17 centers of origin identified for different flower and ornamental crops are given (Table 2.1)

These centers coincide to a significant extent with the regions of the Conservation International’s Biodiversity Hot spots in the world. No one single country is self sufficient in all the germplasm of flowers. The centers of origin of ancient flowers from China and Turkey coincide with the Vavilov’s food crop centers of origin. Domestication of food crops might also lead to the domestication of those flowers. Flowers were part of crop weed complex from the beginning and those with beautiful flowers would have been selected for domestication.

Flowers, the aesthetic creations of God over the earth and symbolize beauty, purity, peace and love. Flowers have been associated with progress and prosperity from ancient times. They have long been associated with each civilization and culture in the world, and are integral part of traditional, religious ceremonies and rituals and no function, from birth till death, are complete without the use of flowers. They play a cardinal role in human behaviour and culture, bringing tranquility and peace of mind. Sensory elements of flowers like fragrance, colour, texture, softness, freshness, etc. influence human psyche in different manner.

From a symbol of love, flowers have transformed into an industry generating both income as well as employment. In the flower industry, significant changes are occurring in the competitive relationships worldwide due to increasing habit of “saying it with flowers” to celebrate major life events, expressing emotions in ways that words are deficient. Estimate of the annual consumption of commercially grown flower vary by source and range from 40-60 billion USD. Global exports over the last few years have grown by more than 10 per cent annually. Flower growing and its value addition viz., essential oils, natural dye extraction, dry flowers, floral ornaments, bouquets and artistic garlands, etc. is associated with variety of employment generation activities. Besides the traditional centres of production, new production centres are also developing.

In the beginning, human kind selected some of the useful wild flowers and brought them to gardens for decoration; mainly used for their floral and other values. The rose, which is an high value flower today, has long history, perhaps older than man. Carnation was grown in Greece during 300 B. C. Orchids were known for their attractive flowers and scent in China about 2500 years ago as mentioned by Confucius. Chrysanthemum is the another oldest flower grown in China as early as 500 B. C. At the time of Confucius, only a wild single-flowered type was known in chrysanthemum. Later on many new varieties arose and in Japan, the flower reached a high stage of development and popularity. From Japan, the chrysanthemum spread to Europe. Now some of the best known modern varieties have been developed in Europe, America, and Australia. Lotus, an aquatic ornamental flower, is native to India and is associated with religion, art and culture of Indian civilization. Eloquent references to the aesthetics of these ornaments are available from ancient literature and sculptures. Most of the garden flowers were introduced into Europe for cultivation from their wild habitats between 16^th and 19^th centuries.