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New varieties of bougainvillea have been developed in India at different research institutions, nurseries, botanical societies and also by individual efforts. Details have been mentioned above. New varieties developed at CSIR-NBRI need special mention. 

CSIR-NBRI has developed a number of new varieties by using various available breeding tools viz. through spontaneous mutation, classical breeding, chromosome manipulation and induced mutation (Banerji 2007, 2008, Banerji and Datta 1986, 1988, 1993, 1996, Banerji et al., 1987, Data and Banerji 1990, 1994a,b, Datta 1992b, 2004, Nath et al., 1983, Ohri 1995, Sharma 1996, Zadoo et al., 1975b, Jayanti et al., 2007, Roy et al., 2015).

World trade of fresh cut flower is increasing day by day. Fresh flowers lose their freshness and quality both during travel and also during and after arrangements due to flower specific short vase life. Such deficiencies can be ameliorated through application of nutrient additives to vase water. Use of preservative solutions has been known for many years to increase the vase life of cut flowers. Different methods like use of holding, pulsing and bud opening solution, growth regulators, gamma irradiation, pre-cooling, cold storage, packaging etc. are already in practice in the flower trade to ensure the garden fresh quality of flowers to consumers (Singh et al., 2001). The floral business is expanding in a big way, nationwide.  Sales of cut flowers are rising faster through retailers as every state has entered into development of supermarket chains. Cut flower sale through retailers is  a booming business. Retail growers and Wholesale growers are the major players in our country for domestic market. Retail market suffers from logistic bottlenecks. Retailers do not have any background scientific knowledge to increase the vase life of cut flowers. Flower buyers are very choosy and prefer quality bloom with longer vase life.

Floriculture has become very important industry as a result of science based techniques and steady supply of improved plant materials. One of the major constraints of floriculture industry is non availability of large scale quality planting materials. Conventional methods of propagation can not meet the increasing demand of propagating materials. Micropropagation is perhaps the most widely used biotechnology tool for large scale propagation of floricultural crops. This economic proposition has led to intensive practical research to evolve tissue culture techniques for mass propagation and production of virus-free plant material.  Since most of the ornamental crops are highly heterozygous, their seed progeny is not true-to-type. Conventionally in these plants vegetative reproduction method is followed to produce genetically identical plants at commercial scale. But the main constrain of this method is that only a limited number of plants can be raised in a year from a single mother plant and often fail to meet the market demand. Therefore, most of the modern floriculturists follow the micropropagation technique for rapid multiplication of ornamental plants.

Considering the economic importance of chlorophyll variegation in floriculture trade attempt was made for cytological, anatomical and biochemical analysis of chlorophyll variegated mutants for better and clear understanding of origin of chlorophyll variegation (Kirk and Tilney-Bassett 1967, Datta et al. 1995). Following chlorophyll variegated mutants and their respective original varieties were analysed –

‘Los Banos Beauty’ (LBB) : Original double bracted Bougainvillea with green leaf.

For crop improvement and more specifically to develop new varieties a number of plant breeding methods are available. CSIR-NBRI from very beginning selected all available techniques and standardized their practical application for all ornamental crops. All crop specific basic information was collected/generated for successful application of techniques for development of new varieties by creating genetic variability. Ornamental plant species fall into two main categories. In the first group the plants that are capable of sexual reproduction, but are commercially propagated vegetatively. The second group of plant species are the apomicts. In obligate apomicts hybridization fails to generate any variability. For development of new variety creation of genetic variability is pre-requisite. Breeder should have all up-to-date knowledge about all the available techniques and their merits and demerits for improvement and development of new varieties.

Cytogenetics helps in solving intricate problems of evolution of economic plants and their relationship with relevant wild ancestors. Ornamental plants provide very interesting material for evolutionary studies. Such a study would reveal the nature of the evolutionary steps and clarify the changes that the breeding system and chromosomes underwent. The genetic and cytogenetic reasons for the diversity in ornamentals would also be unraveled. Such a study also helps to chalk out a meaningful breeding methodology for genetic improvement. A systematic programme of genetics and plant breeding of ornamental plants was started at CSIR-NBRI. The objectives of the programme were both basic or creative (experimental analysis of the causes of variation and evolution) and applied or productive (experimental synthesis of new and novel variation with better putative parents). Evaluation of colchiploids of ornamentals with different genetic systems was being carried out at CSIR-NBRI, with a view to explore the possibility of their introduction in floriculture trade. Superiority of polyploid cultivars, in general, has been the main factor, which has induced gardeners to raise artificial tetraploids. Most of the garden forms are of hybrid origin, raised over a number of years and named differently by different workers and nurserymen. More often than not, there is no authentic record of their ancestory and they show a great deal of morphological and cytological polymorphism (Khoshoo 1968, 1990, Datta and Banerji (1995). 

Characterization of Germplasm / Hybrids, Varietal identification, mutants etc.

Accurate identification of plants is desired for patent protection of plant varieties. Accurate characterization is also necessary to trace out the parents of new varieties. Use of present day molecular markers in addition to the classical methods provides more positive identification of new cultivars. RAPD and other molecular techniques have been used in a variety of plant materials for such studies (Sneath and Sokal 1973, Saitou and Nei 1987, Demeke et al., 1992, Selvam and Rajasekaran  1993, 1994, Dubouzet, et al., 1997, 1998, Hallden, et al., 1994, Hu and Quiros 1991, Jain et al., 1994, Matsumoto and Fukui 1996, Williams et al., 1990, Wolff et al., 1995). RAPD technique has been used in the genus Bougainvillea. It is often difficult to distinguish both mutants and hybrids and sports having a common progenitor, or progenitors themselves. Therefore, the industry needs a DNA-based fingerprinting technique to distinguish mutants or cultivars reliably. Reports are available on investigation about the molecular systematics and genetic differences for better understanding of varietal relationships in bougainvillea (Chatterjee et al., 2007, Kumar et al., 2006, Kumar et al., 2014, Hammad 2009, Pavan Kumar et al., 2015). 

The bougainvillea varieties reported from India have been mentioned above. The exact origin of all the varieties are not available. Breeders, sometimes, do not disclose the origin of varieties. An attempt has been made to trace out the mode of origin of different varieties as per available information (Anonymous 1981, Sindhu 2015, Sindhu and Swaroop 2015, Singh 1999, Singh et al., 1999, Nirody 1932, Sharma 1961, 1962, 1963, 1964, 1968, Sharma 1969, Pancho 1963, 1967, Marigowda 1957, Pancho and Elisco 1959, Pancho and Capinpin 1961, Pancho et al., 1961). Information available is not complete in most cases. Following abbreviations have been used – Hybrid Seedling (HS), Bud Sport (BS), Induced Mutant (IM) :

Early reports are always path finders for future research. Earlier studies at CSIR-NBRI on characterization of bougainvillea is so important that it should be highlighted for researchers. Horto-taxonomical description of the leading Bougainvillea species/cultivars have been prepared according to their affinities to the species and hybrid seedlings (Sharma 1986a,b, 1996, Srinivas 1995, Khoshoo 1971a,b, Zadoo et al., 1975a, Jayanthi 1999). 
Abraham Kavoor : Bougainvillea x buttiana, tall, vigorous growth, young branches greenish-coppery, leaf blade ovate, green; thorn long, straight; bracts ovate, yellow-orange.
Abhimanyu : B. peruviana, bud sport of ‘Arjuna’, medium, drooping; branch greenish-coppery; leaves variegated, leaf elliptic, green; thorn long, straight, bracts elliptic, red-purple.
Aida : B. spectabilis, hybrid seedling of B. spectabilis (Lancaster 1940, Calcutta), tall, growth vigorous, young stem greenish coppery, tomentose, leaf blade ovate, base acute, apex acute to acuminate, coppery, old dark green, puberulent, thorn straight, bract young carmine changing to rose madder, elliptic, apex obtuse, profuse blooming, ideal as shrub, and pot culture.

While much has been written about the taxonomy of wild plants, the cultivated plants have always been looked at with suspicion by taxonomists. There might have feeling that cultivated plants are not natural and therefore fall outside the orbit of a taxonomist. It may be that taxonomy of cultivated plants is more difficult due to their extensive distribution needing wide sampling, rampant hybridization and high mutation rate, leading to diversity in their variation patterns. One of the principal advantages of the study of cultivated plants is that more often we know their genetic-evolutionary race history, together with its reasons and diversity. There is, therefore, a need to take up, what may be called as Hortorium Taxonomy, i.e. taxonomy of the cultivated plants so as to put the subject on a proper footing as a prelude to writing a ‘Flora of the Cultivated Plants of India’. The related wild species together with the elemental, basal or parental species of a cultivated species should be classified according to the rule of the International Code of Nomenclature for Cultivated plants based on the cultivar concept. A cultivar is not to be confused with a botanical variety.

Bougainvilleas is a multipurpose plant due to the variation in habit, growth and colour pattern of different cultivars and are grown as pot plants, standard, hedges, bush, climber, bonsai, landscape, as an espalier, factory gardens, institutional gardens, municipal gardens, terrace garden, wind curtain, topiary, pergola and various other multipurpose. Bougainvillea in an urban landscape trained as a “standard”. It is used as an accent plant, a specimen plant, in hanging baskets, in containers, and for bonsai. Bougainvillea is used to decorate all public, home gardens, play ground and office corridor. About 300 cultivars (150 of which were bred in India) have been derived from 4 species, viz. Bougainvillea peruviana, B. glabra, B. X buttiana and B. spectabilis,through hybridization and natural or induced mutation. Indian-raised cultivars are listed in categories for growing as climbers, bushes, hedges, standards and pot plants and are also grouped under bract colour  (Nagpal 1990, Singh 1990, Singh et al. 2015, Sharma et al. 2015, Kumar et al. 2007, Mathur 2000, 2001, 2007, 2015, Richard and Erin 2002, Simon 2005). It is tolerant to a number of adverse conditions like dry soil, saline soil, pollution etc. Bougainvilleas are sprawling climbers and shrubs. They naturally bloom in the spring and seem to bloom harder in drier years. It is very good plant for desert gardens. It can be used as vines, shaped into bushes, into ground cover. Most suitable for landscaping.  Bougainvillea plants can grow easily on walls. Internode length has a strong influence on bougainvillea growth habit and characteristics in the landscape. They are pollution and drought tolerant and very ideal for landscaping of industrial region as well as for road dividers. They are very hardy plants and specially suitable for growing in rocky and arid areas where other ornamental floweing plants do not  easily thrive well (Fig. 10).

Bougainvillea is relatively pest-free. Worms, aphids, and moths might be an issue. Sometimes it gets attacked by spiders which can be controlled by using miticide and by the fungus Phytophthora which is checked by spraying Blitox (copper oxychloride) (Sharma 1996, Banerji 2010). Although it is normally pest-free plants, but may suffer from worms, snails and aphids. The larvae of some Lepidoptera species also use them as food plants, for example the giant leopard moth (Hypercompe scribonia). Leaf spot disease caused by Cercosporidium bougainvillea has been reported in the U.S.A. (Sobers and Martinez 1966, Sobers and Seymour 1969). When compared to B. spectabilis, B. glabra has been reported to be resistant or only slightly susceptible to the leaf spot disease (Pal and Swarup 1974). Cercosporidium bougainvillea has been reported in Colombo by Pardo-Cardona (1998) and in Indonesia by Kobayashi and Oniki (1994). The disease can be controlled by spraying copper Carbendazim at the rate of 1 g/l at an interval of 10-15 days. Fusarium wilt caused by Fusarium oxysporum in bougainvillea has been reported in Italy (Polizzi et al., 2010). Bacterial leaf spot caused by Pseudomonas andropogonis has been reported in Brunei, Darussalam (Peregrine and Ahmad 1982, Sivapalan and Hamdan 1997) and U.S.A. (Walker 1991, Walker and Hodge 1991). This can be controlled by spraying copper oxychloride at the rate of 3 g/l at intervals of 10-15 days.

Bougainvillea can grow in almost all kinds of edaphic conditions except in the water lodged regions. They grow well in the degraded soils (black cotton soils, red soils, crevices of rocks, to some extent in sandy soils, water stress conditions, high and low pH soils). Open sunny location is most suitable for best performance. Full sunshine helps for producing brilliant colours in masses. But young plants must be protected from heat. Kuzmina-Medova (1986) estimated that Bougainvillea require more than 2000 lux light for satisfactory growth. Different floricultural crops are propagated/multiplied by different means like sexual propagation (by seeds), asexual propagation (cuttings, layering, grafting, budding) and micropropagation. Bougainvillea is mostly propagated by vegetative propagation i.e. hard wood cuttings but it can also be propagated by different conventional propagation methods (Watson and Criley 1973, Iredell 1994, Srinivas 1995, Sindhu and Dagar 2015, Rajan et al., 1998, Tavares et al., 1998, Criley 1997, Pertuit 1999, Gilman 1999, Hackett et al., 1972, Schoellhorn and Alvarez 2002, Hamilton and Midcap 2003).

As mentioned above, all the present day Bougainvillea cultivars being grown in India are either exotics introduced from abroad (Africa, USA, U.K., South Africa, Australia, Philippines, Sri Lanka, Jamaica, Canary Island, Singapore, Java, West Indis etc) or developed by concentrated efforts of nurserymen, individuals or scientific institutions. Bougainvillea are widely grown in Indian gardens. There are numerous varieties and cultivars that are important from floriculture point of view. Most of the present day varieties have arisen through bud sports, chance crossing and induced mutation. India is one of the major repository of wide range of genotypes of Bougainvillea and is perhaps the foremost among nations which have done appreciable good work on Bougainvillea. The genetic variation in plants is considered to be an unlimited resource. The main aim of germplasm collections are assemblies of genotypes or populations representative of cultivars, genetic stocks, wild species etc. which are maintained in forms such as plants, seeds and tissue cultures. The primitive cultivars and wild relatives of crop plants constitute a pool of genetic diversity.  The  germplasm collection and conservation of plant genetic resources provide the diverse raw materials for immediate or future breeding programme. Activities that relate to the conservation and use of plant genetic resources include : exploration and collection; characterization and evaluation; conservation; assessment of variation and identification of useful genes; and exchange and genetic enhancement. Germplasm are the basic raw materials, which after proper screening can be utilized either for direct commercial exploitation or can be used in breeding programme for developing new and novel varieties.

The genus Bougainvillea, although having broad range of adaptability along with diverging habitate is not rich in scientific literature. The available literature on description of elemental species and mode of origin and description of different sports (cultivated species) are very poor and all the literarture are not available at one place. On the basis of available literature (Philbert 1789, Humboldt and Bonpland 1808, Fitch 1854, Bailey 1914, Merril 1923, Standley  1931, Heimerl 1934, Hottes 1947, Bor and Raizada 1948, Preston 1950, MacSelf 1951, Sargeant 1951, Van 1951, Crane and Lawrence 1952, Holttum 1955a-d, 1957a,b, Pancho and Bardenas 1959, Marigowada 1961, Sharma 1962, Menninger 1970, Ramcharan et al., 1974, Zadoo et al., 1976, Linnaeus 1789, Swarup and Singh 1995, Willdenow 1798, McDaniells 1981, Rodale et al., 1997, Gordon 2002, Lopez and Galetto, 2002, Fatima et al., 2007, Kent et al., 2007, Kobayashi et al., 2007a,b, Hammad 2009, Lack, 2004, 2012) an attempts has been made to give a short description of elemental species and important role played by Bougainvillea cv. 

Bougainvilleas are widely grown in India for multipurpose uses.  There are numerous varieties and cultivars that are important from floriculture point of view. Bougainvillea profusely flowers almost all the year round except in rainy season and very severe winter. It has earned a pride place in the floriculture and landscaping due to its variegated foliage and colourful bracts. Bougainvillea belongs to the family Nyctaginacea and in the tribe Mirabileae. It is the only genus in the monotypic subtribe Bougainvilleineae (Gills 1976, Hammad 2009). The first generic name as Bouginvillea was published by A.L. de Jussieu (1789) in his work ‘Garden Plantarum’. The spelling of the generic name subsequently changed about half a dozen times. Finally as per International Code of Botanical Nomenclature, it was spelt as Bougainvillea as used by Spachs (1841) and published in the Index Kewensis (Suppl. 9 : 1931-1935; c.f. Sharma 1996). Heimerl (1900) recognized 10 species, three of which (B. spectabilis Wild., B. glabra Choisy and B. peruviana Humb. and Bonp.)

Bougainvillea plants are native of South America from Brazil west to Peru and south to southern Argentina (Chubut Province). A native to coastal Brazil, the bougainvillea was discovered in 1768 in Rio de Janeiro by French naturalist Dr. Philibert Commerçon (also sometimes spelled Commerson). The plant is named after his close friend and ship’s admiral Louis-Antoine de Bougainville, who commanded the ship La Boudeuse that sailed around the world between 1766-1769, and in which Commerçon was a passenger. Twenty years after Commerçon’s discovery, it was first published as ‘Buginvillea’ in Genera Plantarum by A.L. de Jusseau in 1789. The genus was subsequently spelt in several ways until it was finally corrected to ‘Bougainvillea’ in the Index Kewensis in the 1930s. Originally, B. spectabilis and B. glabra were hardly differentiated until the mid 1980s when botanists recognized them to be totally distinct species. Bougainvillea spectabilis Willd., a native of Brazil reported to be found wild in all provinces of that large country (Taillemite 1977, Forzza 2010). The oldest herbarium specimens of Bougainvillea spectabilis Willd. were collected during the brief stop of the Étoile in Rio de Janeiro. Two are kept in the General Herbarium of the Muséum National d’Histoire Naturelle in Paris (P 00169376, images in Monnier et al. 1993 : 176 and Jolinon 2004 : 79; P 00307018), and two in the Jussieu Herbarium conserved in the same institution (PJuss.; IDC 6206, No. 

Like many other beautiful plants, Bougainvillea has been chosen as the symbol of a host of countries, regions and municipalities. It is the National Flower of the Caribbean Nation of Granada and the United States territory of Guam. It is also the official flower of several counties in Taiwan and Malaysia. In the United States, Bougainvillea is the floral symbol of three California cities (Camarillo, Laguna Niguel and San Clemente). Bougainvillea spectabilis: Paper Flower; Common name: Bougainvillea; Scientific name: Bougainvillea spp.; Hindi: Baganvilas (Booganbel); Manipuri : Cherei; Bengali : Baganbilash; Marathi: Bougainvillea (Booganvel); Konkani: Bouganvila; Telegu: Bogam Malle (Kagithala Puvvu); Malaysia: Bunga kertas, buganvil, buginvila;  Indonesia: kembang kertas; China: Ye Zi Hua; Spain: Bouganvilla, Aka Buganvilla; Mexico and Philippines: Bugambilia; Honduras: Napoleon; Colombia, Nicaragua, El Salvador, Costa Rica and Panama: Veranera; Colombia, Cuba, Panama, Puerto Rico, Dominican Republic and Venezuela: Trinitaria; Argentina, Bolivia, Brazil, Paraguay and Uruguay: Santa Rita; Northern Peru: Papelillo.

Horticulture includes fruits, vegetables, floriculture, spices, tubers, plantation crops, medicinal and aromatic plants and mushrooms. The sector has established its importance in improving land use, promoting crop diversification, generating employment and above all providing nutritional security to the people. Even though India is the second largest producer of horticulture produces in the world, our per capita consumption of fruits and vegetables are very low.

Borer pests cause significant yield losses and are one of the most serious production constraints in tropical vegetable production. For instance, eggplant fruit and shoot borer (EFSB), Leucinodes orbonalis Guenée (Lepidoptera: Pyralidae) reduces yield as much as 70% (Dhandapani et al., 2003). Tomato fruit borer, Helicoverpa armigera Hubner (Lepidoptera: Noctuidae) causes about 5 to 55% loss in almost all the tomato producing areas in the world (Kashyap and Batra, 1987). Up to 80% yield losses have been reported in various vegetable and grain legumes due to legume pod borer (LPB), Maruca vitrata F. (Lepidoptera: Pyralidae) damage (Singh et al., 1990; Sharma, 1998; Gressel et al., 2004; Hammig et al., 2008; Zahid et al., 2008). Due to higher yield losses, growers tend to apply extremely high quantities of chemical pesticides to control borer pests on vegetable crops. Because the borer larvae are exposed on external plant parts only for a brief time after hatching, the window for effective pesticide application is very brief; vegetable farmers spray throughout the growing season, but without satisfactory results. A survey of pesticide use in Bangladesh indicated that farmers spray up to 180 times with chemical insecticides during a year to protect their eggplant crop against EFSB (SUSVEGAsia, 2007). Pesticide application often exceeded 50 sprays per tomato crop season in south India (Nagaraju et al., 2002). In Bangladesh, country bean (Lablab purpureus) is being sprayed at weekly or biweekly intervals—sometimes every day—to control LPB (Hoque et al., 2001). On average, farmers used 10-24 kg/ha of pesticides in cabbage and cauliflower in India to manage the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) and other pests (Weinberger and Srinivasan, 2009).

Ash gourd (syn:wax gourd, winter melon, white gourd, white pumpkin, ash pumpkin, Chinese preserving melon and hairy melon) is a vegetable belonging to family Cucurbitaceae and genus Benincasa with only one cultivated species, Benincasa hispida (Thunb.) Cogn. (2n=2x=24). Ash gourd is an important vegetable especially in the Indo-China region, which is also the major producer of ash gourd (Rubatzky and Yamaguchi, 1997), but it is also a potential crop of tropical Africa and America (Sirohiet al., 2005).

Spices are defined as a strongly flavored or aromatic substance of vegetable origin, obtained from tropical plants, commonly used as a condiment. India is known as ‘land of spices’. Chilli (Capsicum annuum L.) also known as hot peppers and Capsicums also referred as bell peppers or sweet peppers belong to the genus Capsicum which is a member of the Solanaceae family. The native home of chilli is considered to New Mexico with secondary origin at Guatemala. They are known from pre-historic remains of Peru. Chilli was introduced into India by Portuguese in 16th century. Chilli is considered as one of the major commercial crops of the world. Both green and dried chillies are the important components of our routine diet. Chilli also contains vitamin A, C and E. It will give the required pungency, colour, taste and flavour to our dishes. The presence of capsaicin in chilli is responsible for its pungency and it has medicinal value. The extracted capsaicin is used in pain balms, cosmetics and medicines related to heart diseases. Capsanthin, a pigment in chilli is used for natural colouration to Jams, Jellies and squashes, since it is a natural pigment and no harmful or side effects on human health. Oleoresin is used in pain balms, vapours, etc. Hence, there is lot of demand for chilli oleoresin in the world market. The largest producer of chillies in the world is India contributing 52 per cent of world production, accounting for 11.67 lakh tonnes of production from an area of 7.5 lakh ha with 1550 kg/ha of productivity followed by Nigeria (17%), China (16%), Peru and Bangladesh (6%). India exported 1.8 million tonnes of chilli during 2009 (Reddy, 2010).

Recently people are moving towards newer trends in food diversification for value addition. The beneficial effects could be either maintenance, promotion or well being of health or reduction of the risk of a pathogenic process or a disease. Genetically modified (GM) crops / foods, algae, mushrooms and probiotics are among the important functional foods which apart from improving health also protect against infections and/or stimulate immune systems. The interactive research between physiology, microbiology, food technology and molecular biology may produce many healthful, diversified value based food products for human consumption. The concept of value addition in food is changing significantly. Earlier the emphasis was on survival through hunger satisfaction but today it is aiming towards food safety and food sciences at developing foods which promote good health and reduce the risk of major diseases. With these efforts, these products have come into the market and are identified as functional foods. These include foods containing phytochemicals, dietary fibre, structural lipids, bioactive peptides, polyunsaturated fatty acids.

Recent awareness of consumers towards innovative probiotic fermented food products containing friendly bacteria and healthier foods has coined the term functional foods. Food development in the world is taking place mainly in three strategic directions as functional foods, organic foods and national foods. Every year the global demand is increasing at the rate of 15–20 %.

Fermentation by newer technologies involves specific strain of lactic acid bacteria. This brings specific fermentation under controlled conditions resulting in a specific fermented product with enhanced organoleptic, nutritional and therapeutic qualities.

Pomegranate is one of the oldest known edible fruits and is associated with ancient civilizations of the Middle East. From its origin in the area now occupied by Iran and Afghanistan, the pomegranate spread east to India and China and west to Mediterranean countries (Turkey, Egypt, Tunisia, Morocco, and Spain). Spanish missionaries brought the pomegranate to the Americas in the 1500s (Hodgson, 1917; LaRue, 1980). The primary commercial pomegranate growing regions of the world are the Near East, India and surrounding countries, and southern Europe. The fruit is consumed fresh or processed into juice, syrup, jams, or wine (Fig. 1) (LaRue, 1980; Adsule and Patil, 1995; Kumar, 1990; Patil and Karale, 2001; Roy and Wasker, 1997).

The potato (Solanum tuberosum L.) is one of the four most important food crops of the world, the other three being rice, wheat and maize. It is a high yielding and nutritive crop and produces highest dry matter, carbohydrates, edible protein, minerals and vitamin C and B per unit of area and time. In view of the shrinking cultivable land area and increasing population of India, the potato has a high potential to solve the problems of hunger and malnutrition in our country. But, potato is a perishable commodity and its harvest time (February/March) in Indo-Gangetic plains (which account for nearly 87% of the country’s potato production) coincides with steep rise in ambient temperatures. From April onwards, temperatures start shooting up and the produce has either to be consumed within a short period of time or is required to be preserved in the cold stores. Due to inadequate, expensive and unevenly distributed refrigerated storage facilities in the country, there have been frequent gluts in the market causing substantial economic losses to farmers and wastage of precious food. Such gluts occur every 3 to 5 years. The glut years are followed by a reduction in potato area and production leading to high potato prices in alternate years which again encourage farmers to increase potato area in subsequent years resulting again in a glut situation and price crashes. This boom and bust cycle has thus continued for long (Pandey et al., 2009).

Consumption of fruit and vegetables has dramatically increased globally during the past a few decades. These are living perishable biological entities which perform a number of metabolic functions and have a short life span. Once the fruit is harvested, respiration and transpiration continue, but only for as long as the fruit can draw on its own food reserves and moisture. It is this limited ability to continue vital metabolic functions which define fruit as perishable. It is also estimated that about 20% of all fruits and vegetables produced are lost each year due to spoilage. The process of the fruit spoilage is just the decomposition of the fruit itself. Once harvested, this begins to deteriorate until eventually it becomes unfit for consumption. This deterioration is known as decay and that leads to spoilage. Latter may be defined as “any sensory change (physical, visual, olfactory or flavour) which the consumer considers to be unacceptable. The gradual changes which cause deterioration and decay in fruits are due to certain organisms and chemicals present in the food and outside the food. Carbohydrates play a major role in the fruit spoilage process (Prasanna et al., 2007) by way of depolymerization leading to decreased molecular size with concomitant increase in the levels of ripening inducing specific enzymes, whose target differ from fruit to fruit. The major classes of cell wall polysaccharides that undergo modifications during ripening are pectins, cellulose, starch, and hemicelluloses (Hallet et al., 2005). The focus of this chapter is to provide information about carbohydrate metabolism during fruit spoilage.

Sustainability refers to productive performance of a system over time. It implies use of natural resources to meet the present needs without jeopardizing the future potential. The Technical Advisory Committee of the Consultative Group of International Agricultural Research has defined sustainability as “Successful management of resources for agriculture to satisfy changing human needs while maintaining or enhancing the quality of the environment and conserving natural resources” (TAC, 1989). A sustainable system must be sustainable both ecologically and economically.

During the past several decades, production of horticultural crops has undergone a tremendous change in both developed and developing countries due to the development and use of fertilizers, pesticides, mechanization, soil fumigation, container production in soil-less media, breeding, micropropagation, pathogen elimination and a number of other innovations for attaining its future stability and sustainability. Recently, in modern horticulture, enhanced productivity depends heavily on inputs of fertilizers and pesticides to maintain an economic level of productivity. On the other hand, social and economic pressures are demanding that agricultural/horticultural practices, that have a damaging impact on the environment and pose risk to health of mankind, be curtailed. Thus throughout the world, agriculture including horticulture is at crossroads in terms of its future stability and sustainability. The solution for the above lies in developing new technology with reduced use of fertilizer and pesticides besides maintaining a sustainable level of productivity. The increased concern about the sustainability and undesirable side-effects of chemistry-based agriculture is prompting many researchers to more seriously evaluate alternative approaches. One such effort was put forth in the management of microbes that live in the rhizosphere soil around the roots of nearly all terrestrial plants. It has been believed that the main orchestrators of microbial activity in the rhizosphere are mycorrhizal fungi.

The harmony between human beings and plants is one of the evergreen reasons that maintains and supports life on earth. This fact clearly explains why any hazard to the life of plants prominently affects man. One important feature distinguishing plants from other complex multicellular organisms is that plants are sessile and thus have to endure environmental challenges (Zhu, 2001).

Crop productivity is limited by stress factors. The stresses which pose major threats to survival of plants belong to two categories- abiotic and biotic stress. Drought, salinity, high or low temperatures, light, deficient or excess nutrients, heavy metals, pollutants etc., either individually or in combination causes abiotic stresses. Biotic stress refers to any stress provided by living organisms, be it unicellular or multicellular. Plants facing a variety of biotic and abiotic stresses are able to protect themselves by means of tolerance mechanisms which result from changes at the molecular level. They are often confronted by a multitude of stresses in their natural environment. To overcome this, plants have evolved various defence strategies, which involve comprehensive reprogramming of the cellular metabolism.

Understanding biology and genetics at molecular level has become very important for better understanding and manipulation of genome architecture and this creates new opportunities to streamline plant breeding. Breeding is simply defined as the selective mating of individuals of a population to isolate or combine desired morphological, physiological or genetic traits such as appearance, yield, and disease resistance. This is performed with the assistance of identifiable traits.

Molecular markers have contributed significantly in this respect and have been widely used in plant science in a number of ways, including genetic fingerprinting, diagnostics, identification of duplicates and selecting core collections, determination of genetic distances, genome analysis, identification of markers associated with desirable breeding traits which are useful in marker assisted breeding, genomics and development of transgenics. Use of these markers also significantly reduces breeding time and cycles required for crop improvement. This is reflected in the fact that complete molecular and genetic maps have now been constructed for at least 20 major crop species and many more have been characterized at less defined level and the genomes of a few model plant species were completely sequenced.

Climate Change: Understanding our Earth and Atmosphere

Our Mother Earth is the fifth largest planet in the solar system and the third from the sun. It is also the sole planet whose name comes from old English language only, and not from names of any other celestial bodies, whose names originated mostly from Greek/Roman mythology. Earth has a diameter of 6378 km, of which the earth crust (uppermost skin) is only 24 km. Earth is the only planet where water exists as liquid and 71% of its surface is covered by water. The earth’s atmosphere is made up mostly of nitrogen (77%) and oxygen (21%) gases. CO₂ consists of a very small (trace) fraction (0.03%) of atmosphere, but is most vital for the life cycle. When earth was created, it has got much higher CO₂ than today, and all of them have been sequestered in rocks as carbonates and dissolved in oceans and a negligible amount is distributed in plant communities. This extremely small quantity of CO₂ is keeping life on earth, by maintaining earth’s temperature at a comfortable 14°C (without CO₂, earth’s temperature would have been -21°C). This effect is called the ‘greenhouse effect’, revolving which all issues of climate change exist. It is also to be noted that water vapour is also an important greenhouse gas (GHG). It is to also to be noted that in spite of substantial increase in solar constant, earth’s average temperature has remained stable for billions of years. It is understood that this was possible through variation in CO₂, and it is the biological processes (Earth biosphere) that controlled the environment over years (Gaia hypothesis).

In this era of molecular markers in genetic studies, genome analysis encompasses several stages of increasing resolution and sophistication, leading to the generation of high resolution chromosome maps. Since the entire plant kingdom cannot be covered under sequencing projects, molecular markers and their correlation to phenotypes provide us with requisite landmarks for elucidation of genetic variation.

A molecular marker is a site of heterozygosity for some type of DNA variation. Such a DNA marker in mapping analysis is analogous to a conventional heterozygous allelic pair. When they are used for mapping the genome, the identity of this DNA fragment is not important, but is simply used as a reference point to arrange and order the genetic information along the length of a chromosome. The molecular markers provide landmarks along the length of chromosome that facilitate the manipulation of chromosome segments in breeding and chromosome engineering programs.

Delineating species boundaries correctly and also identifying species are crucial to the discovery of life’s diversity because it determines whether different individual organisms are members of the same entity or not (Dayrat, 2005). The identification of species depends on the knowledge held by taxonomists whose work cannot cover all taxon identification requested by non-specialists. To deal with these difficulties, the ‘DNA Barcode of Life’ project aims to develop a standardized, rapid and inexpensive species identification method accessible to non-taxonomists.

DNA barcoding is a technique in which species identification is performed by determining and comparing the sequences of several hundred base pairs of nucleotides from a small fragment of an identified gene, with the aim of contributing to a wide range of ecological and conservation studies in which traditional taxonomic identification is not practical (Krishnamurthy and Francis, 2012). The two main ambitions of DNA barcoding are to assign unknown specimens to species and to enhance the discovery of new species and facilitate identification, particularly in cryptic, microscopic and other organisms with complex or inaccessible morphology (Hebert et al., 2003a). Apart from these, identification of species previously defined by other criteria to also is an objective of barcoding. Another major objective could be the definition of operational units for ecological studies. This may also be used for forensic purposes by linking the specimens with already identified databases.

Ethylene is a primary plant hormone involved in the senescence of plant tissues including flowers and leaves. In carnation, inhibition of the synthesis or action of ethylene delays the onset of senescence symptoms and lengthens the vase life of flowers. Leaves of cut chrysanthemum of some cultivars frequently become yellow, sometimes prior to onset of flower senescence, in response to exogenous ethylene. Generation of transgenic plants with suppressed production or action of ethylene is an excellent way to lengthen the longevity of these ornamental plants. This paper reviews our studies on generation and characterization of carnations with reduced ethylene production and chrysanthemum with reduced sensitivity to ethylene.

Ethylene is a primary plant hormone involved in the senescence of cut flowers of many ornamentals such as carnation, sweetpea and delphinium. It is produced on a large amount at a later stage of flower senescence. The increased ethylene production accelerates withering and dropping of petals. Inhibition of synthesis or action of ethylene delays the onset of senescence symptoms and extends the vase life of flowers.

Years ago before becoming the food producers, humans, for years remained food gatherers and the food collected from wild was sufficient to satisfy the food needs of human on the earth. The ever increasing population demanded more food to quench their hunger which is mainly served by plants but plants have limited intrinsic potential or threshold limit upto which it can put on biomass which ultimately could be consumed as food. Though by making certain modifications in the genetic make-up of the plant, the output can be altered. Before attempting any modification in the genetic make-up, it is necessary to understand the genetics and genetic behavior of the targeted plant. So the aim of studying the genetics and genetic behavior of the plants is to improve the quality and quantity of the produce. The inferences of genetics cannot be directly applied to the improvement but the principles of genetics and the genetic behaviors are set into particular situations. This part of genetics which deals with the improvement of the quality and quantity of the produce with the aim of benefitting mankind is called plant breeding.

When a variety is grown under different environmental conditions, phenotype is the result of genotype+environment+genotype×environment interaction. Genotype×environment refers to the interaction effect of the genotype with different environments. Presence of this interaction leads to overestimation of genetical and biometrical parameters and thus may yield misleading results. This interaction also influences the varietal adaptation of new improved genotypes. Adaptation refers to certain varietal features (morphological and physiological) which promote survival under that environment. In production and breeding programmes adaptability is related to economic yield i.e. genotypes producing higher economic yield under different environmental conditions are comparatively more adaptive than those which produce low yield. Varietal adaptability refers to the capability of a genotype to grow normally and perform well in an environment or different environments. Adaptation of genotypes depends upon certain characters i.e. both morphological and physiological which promote survival under an environment. In natural conditions adaptation is brought by natural selection, but in artificial breeding, adaptation is induced by the breeders.

Hybridization is a potent technique to create variability for selection and breaking yield barriers, evolve varieties having built in high potential. The selection of suitable parents for hybridization is one of the most important step in hybridization program. Selection of parents on the basis of phenotypic performance alone is not a sound procedure since phenotypically superior lines may yield poor recombinations in the segregating generations. It is therefore essential that parents are chosen on the basis of their genetic value. Some of the commonly utilized techniques for assessing the genetic value of a genotype are:

Selection is an important activity in all the breeding programmes. Different types of selections i.e. mass selection, progeny selection and cyclic selection etc. are used depending on the mode of pollination of the crop species, the predominant gene action and the breeding objectives. The efficiency of selection largely depends on the extent of genetic variability present in the population and the heritability of the character. Selection is more effective for character with high heritability than those having low heritability. Breeding for higher or better yield is the breeding objective for most of the breeding programmes, but it has low heritability. Yield is considered to be complex or super character which is influenced by many components or contributing traits both in positive and in negative directions. Due to the fact that it has low heritability, selection is done for the yield contributing traits so that yield may be increased through selection. Prior to selection for yield contributing traits, it is always beneficial to study the extent and type of relationship between the character and yield. There are different procedures which aid in the isolation of superior yielding genotypes from genetically variable populations by providing information on indirect selection for yield. These methods are discussed in the following content.

Important breeding methods can be classified as follows:
    1.    Introduction
    2.    Selection
    a.    Mass selection: Done in self pollinated crops, cross pollinated crops and dioecious crops.
    b.    Individual plant selection: Done in self pollinated crops, cross pollinated crops (line breeding) without control of pollination, artificially self pollinated lines, dioecious plants and clonally propagated lines.
    3.    Hybridization
    a.    Crossing in self pollinated crops.
    b.    Single crosses, double crosses and synthesized varieties.
    c.    Varietal crosses.

Availability of genetic variability and exploitation of this variability are two basic requirements of successful crop breeding programmes. The presence of genetic variation in a character is a must for any improvement in that character. If all the individuals in a population are identical i.e. no variation is there, selection cannot be done, so no improvement will be done. In case of crops, if variation is not present or variation is very small, variations are created through hybridization, mutation, polyploidy etc. Selection is identification and isolation of desirable plants from a variable population. A population consists of large number of heterogenous individuals with different morphological expressions. This variability is contributed by three factors: 1. Genetic constitution of individual, 2. Environmental effect on the individual and 3. Interaction effect between gene and environment. These three factors contribute towards the phenotypic variability among the individuals of the population. Assessment of magnitude of variability present in a crop species is of utmost importance as it provides the evidence for effective selection. Phenotypic variation in a population arises due to genotypic and environmental effects.

Statistics involves procedures for collection, classification, analysis, interpretation and presentation of numerical data (Gupta, 1997). Statistical investigations involves four stages ie. collection of data, compilation of data, analysis of data and drawing inferences. For any statistical analysis, first step is data collection which constitutes the foundation for statistical analysis. The required data may be obtained either through survey or an experiment. Survey is the process of collecting data from a population but have no control over the factors which may affect the population characteristics under study, whereas in experiment, data is collected while control is exercised over the factors which may affect the population characteristics under study. Experiments always and almost provide better information than the survey but surveys are necessary in natural populations. When data is not available, it is collected by any of the two methods i.e. census or survey method. In census method, data are collected for each and every unit of the population whereas in sample method a representative sample is drawn from the population on the basis of which all the conclusions are drawn about the population from that sample.

The frequency distribution of the populations of M₂ and M₃ generation for each genotype was extracted according to Panse and Sukhatme (1961). Skewness and Kurtosis for all the characters were calculated as per the standard method. Skewness refers to the symmetry of the frequency distribution. A measure of skewness is obtained as making use of the second and their moments about the mean. It is defined as,

Polygenic characters exhibit a wide range of expression but the action of genes may be either additive or non-additive. According to Fisher et al. (1932), Smith (1936) Lush (1945), Panse (1946) and Mather (1949) the genetic advance can be achieved through selection of the heritable variation in only due to additive. So, selection for a particular character based on phenotypic variability without estimating the heritable part of it will not be successful. Heritability estimates along with genetic advance are normally more helpful in predicting the gain under selection than heritability estimates alone (Singh, 1997). Therefore, the heritability enters into every formula connected with breeding methods and many practical decisions are taken considering the heritability value.

Knowledge on genetic variability of the available population is very essential for any crop improvement programme, as it will positively enhance the efficiency of selection. The variability in quantitative characters increase considerably by treating the biological materials with different mutagenic agents. It is possible to identify mutants for different characteristics which can be useful in further programme. Variability is measured by different statistics viz., phenotypic coefficient of variation (PCV) and genotypic co-efficient of variation (GCV). GCV would be more useful for the assessment of inherent variability as it exhibits the heritable portion only.

Germination between M₁ and M₂ had a non-significant relationship in germination between M₁ and its corresponding M₁ progenies in M₂ (Table 27). Probably the reduction in the germination in M₁ might be very highly and significantly influenced by the conditions prevailing in germination and physiological disturbances that would be strictly associated in M₁ alone. Whereas the survival of the seedlings between M₁ and M₂ showed a strong positive relationship. The differential behaviour of the mutagens affecting germination and survival was also evident as discussed elsewhere.

However, seedling height on 10^th day sorted a differential relationship between M₁ and M₂. It was negative and non-significant. A non-significant relationship was exhibited for seedling height on 30^th day between M₁ and M₂ in all the doses. It may be interpreted that extent of physiological disturbances that occurred in the early stages and the extend of recovery mechanism that operated subsequently may be the major cause for this; not withstanding the haplontic and diplontic selection that operated in the biological system. Further the type of physiological disturbances happened, whether the enzyme systems affected or a substantial amount of toxic substances produced besides the genetical causes have not been studied in the present investigation. Moreover if the reduced growth was due to mitotic arrest in the meristamatic regions of the roots of M₁ plants, the disorder may not be completely inherited to its offspring’s (M₂ plants), in that sense selection at the cell level damages might occur in the M₁ itself and the selection for a cell with normal mitosis and extent of chromosomal damages that will be tolerated alone might be selected and hence the effect in M₁ need not be always related with M₂; it also depends upon the potency of the cell to recover from the mutagen induced damages. The ability of the cell in general, should be more in M₁ than in M₂ recover the disorder after several cell generations.

A detailed treatment on the concepts of mutagenic effectiveness and efficiency was given by Konzak et al. (1965). They proposed the term “effectiveness” as a measure of gene mutations in relation to the dose and “efficiency” as an estimate of the mutation rate in relation to other biological effects induced, such as lethality, injury or sterility. To obtain high efficiency, the mutagenic effect must greatly surpass other effects in the cell, such as chromosomal aberrations, and toxic effects which generally lead to damage

The induction of mutations in polygenes controlling quantitative characters can be detected by the estimation of mean and variance of progenies from normal looking mutagen treated populations. Induction of micromutations in different crop plants have been reviewed by various investigators like Gregory (1955, 1968) in peanut, Rawlings et al. (1958) in soybean, Oka et al. (1985) in rice, Brock and Latter (1961) in Trifolium, Borojevic (1966) and Scossiroli (1966) in wheat, Gaul (1961a, 1966), Astveit (1966) in barley and Brock (1967) in Arabidopsis.

Though more reliable results can be obtained from the study of quantitative variation in the advanced generations than in M₂ (Aastveit, 1968, and Scossiroli, 1977), an estimation of the extent of induced genetic variability in quantitative traits in M₂ itself will be valuable in providing information for future selection programme. It was therefore considered worthwhile to study the shift of mean values and to gather information on induced genotypic variance heritability and genetic advance for different quantitative traits from families of M₁ from different mutagenic treatments.

Macromutations were observed in the present set of experiments, under all the treatments (Table 12-14).

As the dosage of gamma rays increased, there was a decrease in their frequency. EB showed less mutation frequency than gamma rays and EMS. But in combination with gamma rays it produced more frequency of macromutations. As the dose increased the frequency also increased. EMS as single treatment produced macromutations like that of gamma rays, but in combination with gamma rays it produced more frequency than gamma rays as individual treatment. However, as the dosage increased the mutation frequency was also reduced. Medium dose combination produced more mutations than higher and lower dose combinations of gamma rays + EMS.

On M₂ plant basis, gamma rays in combination with EB produced the maximum viable mutation rate (4.04), whereas gamma rays individually induced a maximum rate of 2.23 and EB as a sole mutagen generated a maximum rate of 0.79. But EMS as a single treatment showed 1.69 as viable mutation rate, in combination with gamma rays it generated as much as 2.49. Combination treatment showed a less than synergistic effect.

Mutation in M₂

The output of mutations in M₂ and subsequent generations solely depends upon the complex interaction between many factors in the treated organism together with the specific modes of action of particular mutagen. These results are expressed quantitatively by the mutation rate and qualitatively by the mutation spectrum. The proportion of mutated plants to normal ones which is the mutation rate can be computed on the number of mutations per 100 M₁ plants (Gustafsson, 1940), number of mutations per 100 M₁ spikes (Stadler, 1928), and number of mutants per 100 M₂ plants (Gaul, 1960). After comparing the three indices, Gaul (1960) has concluded that mutants per 100 M₂ plants provided the best index, as it is proportional to the initial mutation rate and is independent of variations in progeny size and size of mutated sector. In Pisum, Blixt (1966) has confirmed this. Mohan Rao (1972) has reported that in barley, the M₂ seedling method determined the total induced mutation frequency. This method is also superior since it accounted for the components of induced mutation frequency viz., the frequency of mutated initials in each spike primordium and the frequency of spike primordia mutated.

The qualitative output of mutation in M₂ and later generations is expressed as the mutation spectrum which reflects the different frequencies of different mutations. Westergard (1960) found that the alkylating chemicals induced a higher proportion of less drastic mutations such as Viridis compared to extreme mutations such as Albina than those induced by radiations because of their apparent slight effect on chromosomes. Sidorova (1966) found a positive correlation between the spectrum of chlorophyll and the spectrum of morphological mutations.

Experimental mutagenesis is an important unconventional source to produce mutations in high frequencies in cultivated plants. It makes possible the achievement of desired breeding objectives or atleast decisive progress in this direction through selection of mutants. By establishing extensive collection of mutants based on productive varieties excellent sources of valuable material for theoretical studies and for breeding work can be provided. The induced mutagenesis helps in diversifying varieties and in internal rectification. The simultaneous realization of different breeding objectives may be possible through induced mutagenesis especially in leguminous crops.

Stubbe (1959) stated that mutation breeding as a modern method of plant breeding has proved its justification. It mutation breeding, basic information is a prerequisite on the type of spectrum of induced mutations and relative effectiveness and efficiency of different mutagens.