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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.

Ajowan is a profusely branched winter annual herb, seed oil of which is a major source of thymol, being present to extent of 35-60%. Ajowan oil is aromatic, stimulant and carminative.  It possesses antimicrobial activity. Ajowan seeds are employed either alone or in combination with spices and condiments. It is used in pickles, confectionery and beverages.  It is a good remedy for indigestion.  A paste of crushed fruit is applied externally for relieving colic pains.  It is also used in lotions and ointments.

Camphor plant is valued for presence of camphor in its wood and leaves. Camphor is chiefly a pharmaceutical product though it is used in preparation of artificial essential oils like lavender and lavendin.  It is used as incense and in balms of various kinds.  It is employed as a masking agent in perfumery and sometimes used to achieve lift in perfume blends. Redistilled brown oil is used directly in soap perfumes for a masking effect. Oil is a source of safrole which is a starting material for production of various perfumery chemicals. In 13th century, Marco Polo noted that camphor oil was highly valued by Chinese as a medicine, scent, and embalming fluid.

“The way to health is the way to have an aromatic bath and a scented massage everyday”                        Hippocrates

Aromatherapy is the art and science of using fragrant volatile plant oils and herbs including essential oils, for psychological and physical well-being of man by promoting natural healing and health. It is an emerging art of healing through essential oil, which has got therapeutic effect on body, mind and soul.  Essential oils give calmness, emotional and hormonal balance, stress relief and rejuvenation. Medicinal and spiritual properties of scented herbs were noted by ancient Egyptians and Babylonians. Embalming of body of Egyptian Pharaohs was a practice to purify body for afterlife, whereas Egyptian priests used oils and incense as healers. Books were written in ancient Arabia indicating uses and benefits of certain aromas. Perfumed mortar was used by Babylonians to build temples and mosques, for premises cleaning and cleansing aromas. Ancient Greek believed sweet smells were of divine origin and they used to take aromatic bath to drench them in purity. Aromatic bath and scented massage were ways to health for Romans.

Essential oils are products of secondary metabolism and are secreted by specialized cells located in specified parts of most plants. By virtue of certain characteristic properties, they have wide spread use in perfumery, flavouring and medicine. Essential oils are variable mixtures of terpenoids. Since these oils are produced by plants, composition varies with species and variety of plant besides geography, climate and cultivation practices. Since, chemical components are highly reactive, physical and chemical environment to which oil is subjected to during the processes of its extraction, processing and storage have a great influence on final composition. Entire chain of activities from cultivation, extraction, processing, storage to packing has to be perfectly standardized and regulated to assure end product consistency. Being a valuable item of trade, this is important from the point of view of delivering desired activity as well as safety to consumer.

Essential, volatile or ethereal oils are mixtures composed of volatile liquid and solid compounds which vary widely in regard to their composition and boiling points. Plants owe their fragrance to presence of traces of essential oils in different parts. Numerous fragrance materials are present in roots, stems, barks, leaves, flowers, fruits and heartwoods.     
Several processes like distillation, enfleurage, maceration, expression, solvent extraction and fluid extraction are available for extraction of aroma principles. Application of these processes, either singly or in combination depends upon nature of material and essential oil or absolute intended to be recovered.

Though more than 1500 species contain volatile aromatic principles, only around 50 species serve as commercial source of essential oil and aroma-chemicals. Among these, aromatic crops under large-scale cultivation hardly exceeds two dozens. Important aromatic plants of world are classified according to economic part used, growth habit, habitat, crop duration and propagation method besides usual botanical classification.

Aromatic plants synthesise and preserve a variety of biochemical products, many of which are extractable and useful as chemical feed stocks or as raw materials for various scientific investigations. Many secondary metabolites of plants are commercially important and find use in a number of perfumery, flavouring and pharmaceutical compounds. The characteristic property of the plant is due to a variety of complex chemical compounds and hence aromatic plants are generally referred to as ‘natural bio-chemical factories’ or ‘chemical goldmines’.  Not all these natural chemicals can be synthesised in laboratory. Aromatic plants possess odorous volatile substances, which occur as essential oil, green exudate, balsam and oleoresin in one or more parts, namely, root, wood, stem, foliage, flower and fruit.  The term essential oil is concomitant to fragrance or perfumes because these fragrances are oily in nature and they represent the essence or active constituents of plants. They are called volatile or ethereal oils as they evaporate when exposed to air at ordinary temperatures.