eChapters

Computer-Aided Design (CAD) is the use of Computer Technology for the design of objects which are real or virtual. CAD involves more than just shapes. As in the manual drafting of technical and engineering drawings, the output of CAD must convey information such as materials, processes, dimensions, and tolerances according to application-specific conventions. CAD may be used to design curves and figures in two-dimensional (2D) space; or curves, surfaces, and solids in three-dimensional (3D) objects.

Lawn is an integral part of any garden and it gives pleasure while sitting during evening in summer and one can enjoy good sunshine during winter. Hence, it is often referred as “heart of the garden”. It is covered with perennial grass and provides open landscape to the house and adds aesthetic beauty to the surroundings. Good lawn is essential to have in a good garden. It is permanent feature, which occupies 60% share of total garden area. Here in this chapter lawn is divided into two parts. There are approximately 620 genera and 10,000 species of grasses worldwide. Grasses are used extensively used throughout the world for their beauty and utility. Grasses are found from temperate to tropical to arid semi arid regions and suits in most extreme climatic conditions and have adapted to a worldwide climate and zones. Grasses are used as fodder, food, medicinal and for aesthetics purpose and it belongs to family Gramineae.

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

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

The green buildings are the needs of present day in India as well in the world. The easy availability of most of the green materials and equipments in the country has made it easier for designers to adopt local materials to a very large extent in the construction of green buildings. Now, there is an imminent need for service providers, who would be required in large number, not in hundreds but in thousands, as the movement is heading to reach greater heights. The green building movement is here to stay for the benefit of individuals, society and the country at large in the era of climate change.

With increase in the urbanization and industrialization, there is more pressure on available land and natural resources. In coming era, there will be only limited space available for city dwellers. In buildings one can grow a wide range of flowering and foliage plants. Plants not necessarily one confined to the outdoor only but bed room, kitchen, staircases, patios, windows and other locations can be made green with suitable plants. Indian Council of Green Building (ICGB) has developed the rating system.

Green Building in Santiago, Chile

A large amount of materials are used and energy consumed in construction and operation of average building. Many steps have been taken to reduce consumption of energy by developing new types of vehicle, energy sources, recycled materials and designing environment friendly buildings. These buildings are also known as green buildings or green construction or sustainable building.

Mans’ progress in this universe is posing a threat to the environment, we live in. If we do not treat the environment well, nature will have its own repercussions and we will inevitably have to bear the consequences. We have already begun to suffer for not taking care of mother earth in the past. The earth is warming up each year and this rise in temperature will have its effects on the earths’ inhabitants. Pollution, global warming, acid rain, deforestation, extinction of species, depletion of ozone layer, soil erosion and floods are some of the commonly heard problems of the environment and they are seem to be inter related. The objective of ornamental horticulture is the functional and aesthetic integration of people, building and site, using plants and space as its main tools. The necessity of it in landscape architecture is for positive control of the fast changing landscape for the future. Landscape architecture can help a major way to alleviate the earths’ problems. The landscape which includes urban, agricultural forests and other lands becomes a component of nature and thus ensuring that our landscapes are healthy in the first step towards this goal. The landscape gardener is a necessity because very a few people are capable of selecting the right kind of plants for their grounds; they cannot imagine a landscape picture in terms of varieties and groups, the way an expert can. Planning a piece of land with ornamental plants and features transforming it into a beautiful garden requires experience, patience and knowledge about land topography, soils and climatic factors.

The vividity of the garden depends on its design, features and the most vitally on plants, the key elements which make the garden enliven. Selection of variety of ornamentals is done in order to exhibit different form of growth, flowering time, leaf and stem texture, flower colour etc. Therefore trees, shrubs, climbers, annuals, bulbous plants and ornamental grasses usually find place in the garden along with other secondary groups. Plants play a pivotal role in the protection of our environment as well as improving human life. Apart from their physical characteristics, plants aid in cleaning the environment and reducing some of the harsher effects of heat, sound, wind, air and also serves as complementor, attractor, emphasizer, diverter, indicators and provide aesthetic function by creating attractiveness for human activities.

Landscape models focus on both the integrated master landscape planning of a home gardening and specific garden design. The people should be educated to realize the importance of gardening, by providing good parks and gardens in cities for a large population to relax and enjoy the beauty of nature. The plants used in the landscape designing of gardens are directly or indirectly involved in increasing the aesthetic value of the city, changing microclimate, social behaviour of the people, checking pollution etc. The importance of landscape gardening in human welfare cannot be overlooked. Even in an under-developed country as India, people do not live by bread alone. They also need some finer things of life. The models described in this chapter are very basic features of any garden.

Garden Walls

A garden lover will never like to block the view of his garden by putting a wall along periphery of the garden. A garden as it is enjoyed from inside should also be visible from outside but sometimes, it is necessary from safety and beauty point of view to obscure the ugly sight of an open drain. A compromise is to have a low brick wall of say 60-90 cm height and to put over it some grills, so that the view is not totally obstructed from outside. Alternatively, walls from 1.80 to 5.0 m may also be erected based upon the size of the garden.

Landscaping combines elements of art and science to create a functional, aesthetically pleasing extension of indoor living to the outdoors. One initial purpose of landscape design is to blend mans’ technology (house or building) into the natural surroundings. To work towards a desirable landscape design, the landscape horticulturist must have a working knowledge of art elements and design principles.

The “art” is always changing as the plants grow, environmental conditions change and people use the space. For this reason, landscape designers use a design process that systematically considers all aspects of the land, the environment, the growing plants, and needs of user to ensure a visually pleasing, functional, and ecologically healthy design. The design process begins by determining the needs and desires of the user and the conditions of the site. With this information, the designer then organizes the plants and hardscape materials, which are collectively referred to as the features. The features can be physically described by the visual qualities of line, form, color, texture and visual weight—the elements of design. The principles are the fundamental concepts of composition—proportion, order, repetition and unity—that serve as guidelines to arrange or organize the features to create an aesthetically pleasing or beautiful landscape. Knowledge of the elements and principles of design are essential to designing a landscape and working through the design process.

Seed Health Testing

Science of determining the presence or absence of disease causing agents such as fungi, bacteria and viruses and insects in the seed samples.

Seed Borne disease

The seed primordial or the maturing seed may be infected either (i) directly from the infected plant through the flower or fruit stalk and the seed stalk or directly from the seed surface, or (ii)infection from outside may be introduced through stigma or ovary wall or pericarp, and the flower or fruit stalk, and later through the seed coat. A pathogen may penetrate several of these parts of the seed and in turn infect them. The infestation /contamination of the seed may occur during harvesting, threshing and processing. Visualizing the importance of seed borne diseases the Central Seed Certification board has prescribed certification standards for foundation and certified seed for several diseases.

The pathogen may carry with the seeds in three ways.

• Admixture: Pathogens are independent of seeds but accompany them. They are mixed with health seeds during threshing.
• External:The pathogen may be present on seed surface as spores, oospores and chlamydospores.
• Internal: Pathogens establish within the seed with definite relationship with seed parts.

Post-harvest deterioration primarily means the loss of commodity after harvest. It is one of the serious problems for producers, distributors and consumers. Post-harvest deterioration of perishables is the spoilage of fruits and vegetables after harvesting. Perishables are the feed commodities with moisture content between 50 and 90%. Fruits with the size of 5 g to 5 kg or more, high to very high rate of respiration, high generation of heat, soft texture, easily damageable nature and shorter shelf life are more prone to the microbial damage. The post-harvest losses are caused either by pathological, physiological and mechanical means or combination of all these. These perishables because of having minerals, vitamins, and photochemicals (essentially required for the human health) become victim to the several biotic and abiotic factors easily. Once these fruits are detached from the plant are deprived of essential ingredients as hormones, nutrients, water and other requisites. These biotic and abiotic factors apart from rendering the produce unfit for human consumption reduce the aesthetic value, substantial decrease in food value and also organoleptic quality of the vegetables. The fleshy produce are prone to the exogenous agencies such as fungi, bacteria, etc. as well as other endogenous factors such as respiration, senescence, etc. which may lead to poor quality of the produce and also affect market quality. These perishables continue to respire and may carry out various biochemical activities, leading to ripening subsequently to senescence and making them more susceptible to microbial damage. In addition, tropical conditions prevailing in India, which are characterized by high temperature conditions, are optimal for fungal and bacterial infections. In India, the post-harvest losses of fresh fruits and vegetables are estimated to be about 30%. The post-harvest losses have been recorded are 5-20% at farmer’s field due to pre-harvest infection and sorting, 15-20% due to faulty packaging, 30-40% during transportation and 30-40% during marketing.

Plant viruses, like all other viruses, are obligate intracellular parasites that do not have the molecular machinery to replicate without the host. The plant viruses are defined as viruses pathogenic to higher plants. The discovery of plant viruses causing disease is accredited to Beijerinck who determined in 1898 that the plant sap obtained from tobacco leaves with the mosaic disease remained infectious even after passing through a filter. This was in contrast to bacteria, which were retained by the filter. Beijerinck referred to the infectious filtrate as a contagium vivum fluidum, thus, he used modern term virus.

Viruses occasionally cause significant problems in vegetable crops. However, the prevalence and severity of viral diseases differ from year to year. Aphids spread many of the viral diseases observed in vegetables. There are two types of viral transmission by aphids, i.e., persistent and non-persistent transmission. It is important to understand the difference between these two because persistent and non-persistent viruses differ both in their uptake and behaviour within the insect vector, consiquently, tactics used to limit their and spread vary considerably. In persistent transmission, the aphid usually carries the virus for life. Uptake of virus requires extended feeding and after an incubation period of several hours or days, the virus replicates and circulates within the insect. Because of the time required for feeding before acquisition by an insect vector, the spread of persistent virus is favoured by colonizing aphid species that spend time in the crop. Controlling the aphid vectors with insecticides can reduce the spread of persistent plant virus significantly. In contrast, aphids can acquire non-persistent viruses (NPV) within a few seconds after sampling an infected plant. Winged migratory aphids can move quickly from infected plants onto healthy ones, transmitting the virus in the process. Aphids rapidly lose the virus particles from their mouthparts, which are cleaned when they feed on the next available plant and are unable to transmit disease to additional plants. Because of the speed in which aphids acquire and transmit non-persistent viruses, insecticides are not usually effective in controlling their spread. One of the most common viruses found in many vegetable crops is cucumber mosaic virus (CMV). This is transmitted by several aphid species in a non-persistent manner. There are several strains of CMV that can infect over 775 different plant species in 85 families including snap bean, peppers, tomato, lettuce, tobacco and sugar beets. Symptoms vary depending upon the plant species infected but range may be from yellow-green mottling on leaves and fruits to severe stunting of plants. The viral diseases affecting different vegetable crops are being discussed below:

Vegetables being good source of carbohydrates, proteins, minerals, vitamins and dietary fibers constitute important component of human diet. These are the cheapest source of natural protective food and increase the palatability. India is the second largest producer of vegetables next to China. Diseases are inherent component of agro-ecosystem, which must be dealt with continuous and knowledgeable basis. Diseases in the standing crop from the seedling stage until harvest and spoilage caused by microorganisms during transit, storage and marketing are major constraints in increasing production and availability of vegetables. At different stages of vegetable production, disease management requires several approaches, and it is more successful, if it is integrated into crop production system. Since vegetables are mostly grown year after year in the same fields especially near towns and cities, therefore, concerted efforts are required to manage the diseases. More than 300 diseases have been reported to occur on vegetable crops and it is beyond the scope of this chapter to discuss all the diseases. However, brief description of etiology, diagnostic symptoms and management practices being adopted are presented here for the economically important fungal and bacterial diseases of vegetable crops.

Seed viability tests

Only two methods, the Topographical tetrazolium (TZ) test and the embryo excision test were previously accepted by the International Seed Testing Association as official methods for some species of seeds. ISTA has recently accepted the X-ray method as a valid alternative to the cutting test for the detection of empty and insect-damaged seeds. The following tests can be applied depending on the circumstances.

Introduction

Agricultural soils harbour a rich variety of nematode fauna, where they coexist with a myriad of other microorganisms. It has been estimated that one cubic meter soil of highly fertile field may contain as many as 3×10¹⁴ bacterial cells (300 g), 5×10⁸ protozoa (39 g), 1×10⁷ nematodes (12 g) and fungi (400 g), besides other organisms. The nemic fauna comprises of free-living (saprophagous and microbivorous), predatory forms and plant parasites (phytophagous). In addition, certain animal and insect parasitic forms may spend a part of their life cycle in soil. Plant parasitic nematodes (PPNs) exist in poly-specific communities and attack all types of plants- cultivated or wild. They possess a needle-like stylet or spear at their anterior end, which is used to puncture the plant cells and ingest the cell contents. Majority of PPNs dwell in soil and draw their nutrition from plant roots. Only a few forms attack the above ground plant parts such as stem, leaves, inflorescence and seeds. PPNs may be ectoparasites (feed from outside and do not enter plant tissues) or endoparasites (enter inside the plant tissues). The endoparasites spend a part of their life cycle in soil or may come out into the soil to re-infect the other roots. These may be further categorized into migratory or sedentary types. The migratory forms keep on moving, feeding and laying eggs that are scattered in soil or plant tissues. The sedentary nematodes are more harmful and a particular stage of their life cycle infects the plant and establishes a feeding site by modifying plant tissues by their enzymatic secretions. The females of sedentary nematodes usually attain swollen shapes upon maturity and lay hundreds of eggs in clusters.

Plant parasitic nematodes are ubiquitous, and so far, more than 1800 species have been recorded. They are obligate parasites and must feed upon plant hosts, thus, debilitating the plants to some extent. The extent of direct damage by the nematodes to plants depends on several factors viz., nematode density in soil, nature of parasitism (ectoparasite or endoparasite), host susceptibility, cropping pattern, edaphic factors (mainly soil texture and moisture) and ambient climatic conditions (like temperature and relative humidity). Nematodes, by themselves, rarely kill the plants to ensure their own survival. Nematodes also inflict considerable indirect damage to crops by interacting with other plant pathogens (fungi, bacteria and viruses) to cause disease complexes in which nematodes act as incitants, aggravators, or vectors.

India is contributing about 10% of the world’s vegetables, and in terms of production, the country stands second after China. The existing area under vegetable cultivation in India is around 6.89 million hectare with a production of about 96.54 million tonnes. There will be a demand of 151-193 million tonnes of vegetables in India by 2030 (Dhaliwal et al., 2006). There are extensive crop losses in vegetable crops due to increased insect infestations. Since vegetables are grown round the year, there is carry over of insect-pests across the seasons and also from sowing until harvesting. Vegetables also invite more pest problems because of their cultivation under high fertility conditions leading to high plant succulence. High yielding varieties and hybrids are further more prone to the attack of insect-pests. Insect infestation affects the quality and market value of vegetables adversely and it is estimated that 30-40% of the total production is lost due to the attack of pests (Lal et al., 2004). A large number of pesticides are being used repeatedly to manage the insect-pests in India. Indiscriminate use of pesticides has led to many problems like toxic residues in edible parts of the vegetables, adverse effects on non-target organisms and beneficial insects, resurgence of secondary pests and development of resistance in major pests to pesticides and also environmental pollution. Therefore, latest approach has been to minimize the use of highly toxic insecticides by integrating different strategies of pest control like use of biological control agents, pesticides of plant origin, insect resistant varieties and other cultural practices. In this chapter, efforts have been made to highlight the distribution, host range, identifying characters, biology and nature of damage of important insect-pests of vegetables and also the methods of their management crop or pest wise.

Seed germination

It is defined as the emergence and development from the seed embryo, of those essential structures, for the kind of seed in question, indicates its ability to produce a normal plant under favourable conditions. The seedlings devoid of an essential structure; showing weak or unbalanced development; decay or damage affecting the normal development of seedling are not considered in calculating the germination percentage.

Concern for improvement of nutritional quality of vegetables has arisen in the context of providing nutritional security to our ever-increasing population. Nutritional security denotes the consumption and physiological use of adequate quantities of safe and nutritious food by every member of the family and encompasses the process of equitable distribution among members of household and communities (Nandi and Bhattacharjee, 2002). This would entail the need to ensure a varied food intake, comprising all the essential macro-and micronutrients (protein, carbohydrates, minerals and vitamins), plant pigments (lycopene, beta-carotene, anthocianin, lutein, capsanthin, zeaxanthin, etc.) and other functional phytochemicals (secondary metabolites, like flavonoids, isothiocyanates, glucosinolates, etc.) through a diversified diet. In this regard, production and consumption of vegetables that are the valuable source of micronutrients, beneficial phytonutrients and highly functional phytochemicals hold the key in assuring nutritional security.

Implication of vegetables in diet has been well conceived among the high-income group in the world since human health in recent years has assumed an unprecedently important status. Increased interests in nutrition, fitness and beauty have exaggerated concerns over diet and human health. A new diet-health paradigm is evolving which places more emphasis on the positive aspects of diet. Foods have now assumed the status of functional foods, which should be capable of providing additional physiological benefits, such as preventing or delaying the onset of chronic diseases as well as meeting basic nutritional requirements so with high-income elasticity, the demand for vegetables and perception of diversified diet have been growing steadily, hence, both access and consumption of vegetables have been increasing in the urban and peri-urban population groups. However, meeting the requirements for macro- and micronutrients for most of the population groups in households and communities of South Asia, Latin America and African countries seems far off because of meager presence of vegetables in the diet. In south Asia where meat intake is low, ascorbic acid emerges as one of the most important enhancers of iron absorption. This is attributed to the fact that foods containing vegetables may provide an optimal mix of minerals, vitamins, antioxidants, dietary fibers and other non-nutrients bioactive compounds.

Diseases of plants are produced by a variety of organisms from plant and animal kingdoms viz., fungi, bacteria, viruses, nematodes and insects. The diseases reduce total biomass (dry matter) production and consequently yield of the crop by general stunting, damage to the leaf tissues, fruits and seeds or by killing the plants. The degree of damage would depend upon the intensity of infection but both need not be proportional. One serious effect of disease is the disappearance from cultivation of otherwise excellent but susceptible varieties.

Vegetable crops have been found to be highly susceptible to biotic stresses from the disease causing microorganisms and insects-pests. The ability of pathogen and insect-pests to attack and proliferate in the host plant is highly specific. There are wide differences in the host plants in response to the attack by pathogens and insects. Although control of the diseases and insects by the use of chemicals is possible to certain extent but indiscriminate use of fungicides or insecticides over the crop has several disadvantages. Besides increasing cost involved in chemical control, residual toxicity of the chemicals such as fungicides, antibiotics and insecticides in food chain and development of resistance against pathogens and insect-pests to different chemicals are serious problems.

Genetic improvement of host plants conferring resistance to diseases and insect-pests is considered to be the best approach in the management of diseases and insect-pests, and this is more particularly true in case of vegetable crops. Indiscriminate use of chemicals in the vegetable sector has led to health hazard. This has resulted in switching towards organic vegetables. However, cost of production of organic vegetables naturally will not permit the common people to consume these products. Therefore, the best option is to induce resistance in the host varieties. The resistant varieties could in turn be an important component in the organic vegetable farming, thereby reducing cost of production to certain extent.

Purity analysis

Purity of a seed lot indicates in percentage how large a fraction is made up of pure seeds of the species in question, and how much is made up of inert matter and other seeds. Impurities may be any non seed material (leaf, flower, fruit fractions, soil etc.), small fractions of seeds of the actual species, as well as seeds of other species. Pure seed may include both dead and empty seed, plus damaged seed, purity does not tell anything about viability. The purity analysis of a seed sample in the seed testing laboratory refers to the determination of the different components of the purity viz., pure seeds, other crop seeds, weed seeds and inert matter. Each component is reported as a percentage of total weight. The objective of the purity analysis is to determine whether the submitted sample conforms to the prescribed physical quality standards with regard to physical components. Large seeds are generally easy to clean and purity analyses are therefore often omitted. However, for smaller seeds contamination with other seeds may occur e.g., during processing.

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

Vegetables have always been looked upon as an essential part of diet and are necessary for human health and well-being. Vegetables supply many kinds of nutrients, e.g., carbohydrates, proteins, minerals, vitamins, fibers, phytochemicals, etc. and also add flavour, colour and crispness to foodstuffs. For developing modern day vegetables, breeders have utilized an understanding of genetic principles and applied them for the improvement of these crops. They often make crosses (hybridization) between a crop plant and a related or wild species (a wide cross) enabling valuable genes to be used for genetic improvement of the crops. Over the last few decades, molecular breeding is supplementing plant breeder’s efforts for accelerated genetic enhancement bringing about a revolution in this area. This approach demands efficient procedures for the routine introduction of foreign DNA into plant genomes and utilizing them for the production of novel types of vegetable. In this chapter, attempts have been made to review most of the available molecular breeding techniques, which can routinely be employed in various aspects of vegetable improvement.

Cultivars are developed by selecting for desired traits or by removing undesirable traits that are controlled by genes (the blueprint for all characteristics in living organisms) from existing varieties or breeding lines. The plant species, varieties and clones are identified or selected by their physical features since olden times. However, these traits would change with respect to environmental and climatic conditions. The biochemical parameters like enzymes, proteins, alkaloids, etc. are also likely to change due to the stages of development of plant tissue. Successful selection strategies are dependent on the breeder’s ability to distinguish genetic effects from environmental effects on a visible or measurable trait. Therefore, the scientists resorted to use ‘genetic marker’, i.e., any stable and inheritable variation that can be measured or detected by a suitable method and can be used subsequently to detect the presence of a specific genotype or phenotype, which otherwise is very difficult to detect. Presently, the breeders and scientists all over the world are pursuing mostly DNA or molecular markers.