eChapters

Among angiosperms, there are about 18 families which have more than 30 genera which produce tubers. Most genera have many species which are tuberizing, most of which are unknown to man even now. The history, origin and distribution of only a few species which are economically important root and tuber crops and which are commonly used by men for edible as well as medicinal purpose are elucidated in this chapter.

1. Sweet Potato

Exact centre of origin of sweet potato (Ipomoea batatas), and the routes and times for its dispersal to some of its present locations, are still in dispute and are likely to remain so until further archaeological or ethnobotanical evidence is available (O’Brien, 1972).

Hog-plum also known as wild mango (Spondias pinnata), is native to tropical Asia. A small, aromatic deciduous tree, up to 27m height and 2.5m in girth, with a clear bole of 16m, is found wild or cultivated almost throughout India, ascending up to an altitude of 1500m in the Himalayas; also found in the Andamans. Bark thick, aromatic, smooth, grey; leaves imparipinnate, 20-60cm long, leaflets 5-11, 22-28cm long, ovate-oblong, elliptic or elliptic-oblong, more or less oblique with mango-like smell; flowers whitish or greenish white, polygamous, in large, terminal panicles; fruits in terminal clusters of 10-15, drupes yellow-green or rich olive-green, mottled with yellow and black, smooth, ovoid, 4-7cm long; seeds 1-3, one being perfect, oblong-elliptic. Fruit is extremely sour, even when completely ripe.

A kitchen garden/ nutrition garden is a vegetable garden where the vegetable crops are grown in the backyard of a house or any available space in compound or rooftop of the house, to meet the daily requirement of the family. All the members of the family are collectively involved in a kitchen garden.

For a balanced diet, 300 g of vegetables are to be included in our daily food. But on an average, Indians take only 160 g per day. Hence to fill up the gap, vegetable cultivation not only in farmers’ holdings but also in the home gardens is encouraged.

Even while the world is ageing, it is not prepared for it. There are 962 million people over 60 in the world as of 2017 with 310.0 million of them living in wealthy countries and 652.2 million in developing ones, according to data from the UN's Department of Economic and Social Affairs (DESA-UN 2017). According to projections, there would be 2.1 billion seniors worldwide by the year 2050 (rich countries: 421.4 million, developing countries: 1670.5 million). By 2030, 80% of the old people in the globe will live in developing countries (DESA-UN, 2015). Elderly individuals in rural developing countries confront challenges such as the lack of pension coverage, work difficulty and high medical costs. Their poor diets and deteriorating poverty raise their risk of chronic illnesses like diabetes, heart disease and cancer (Marshall et al., 2001). 

ABSTRACT

The Cry2A proteins are promising candidates for managing the development of Cry1Ac resistance in insects. The Cry2A class of proteins is different from that of Cry1A, and experiments have shown that insects resistant to Cry1Ac are not cross-resistant to Cry2A proteins. However, the Cry2A proteins are less toxic than Cry1Ac to the polyphagous pest Helicoverpa armigera. Structure-based protein engineering of Cry toxins may pave the way for directed evolution of variants with broad spectrum of insect species specificity, enhanced potency, and stability. In the present study homology modeling of Cry2Ac was done using DeepView software. The template for Cry2Ac protein sequence (accession number X57252) was selected using ExPdb template search. The raw sequence of the Cry2Ac was superimposed over the Cry2Aa PDB template (1I5P). The superimposed model was submitted to the SWISS Model server. After receiving the Cry2Ac model, energy minimization was done using Gromos96. The threading energy and force field energy were calculated. The homology model of Cry2Ac made by us along with the Cry2Ac model from the SWISS-MODEL Repository was used for comparative analysis of receptor binding regions of Cry2Aa. Results showed variation between the two highly homologous Cry2A proteins in their receptor binding regions which may account for differences in spectrum of insecticidal activity.

1. INTRODUCTION

In plants, seed dormancy is controlled by temperature, light and hormones. Unlike animals, which secrete hormones from special glands, hormones are always present in plant cells. Each plant hormone plays multiple roles, depending on the site of action, the life stage of the plant and the hormone’s concentration. A plant hormone is any chemical that is produced in one part of the plant that has a targeted function elsewhere. Certain hormones induce and keep seeds in a dormant state, while others cause seeds to break dormancy and initiate germination They are stored in regions where stimulus are and then released for transport through either phloem or mesophyll when the appropriate stimulus occurs. These are chemical messengers influencing many patterns of plant development

The first theory is that the five classic plant hormones, auxin, cytokinins (CKs), gibberellins (GAs), ethylene, and abscisic acid (ABA), plus the new plant hormones, brassinosteroids (BAs), and salicylates or salicylic acids (SAs) can be gathered into three groups. These are growth hormones, stress hormones and shock hormones. Auxin and CKs are growth hormones. Ethylene, GAs, and brassinosteroids are stress hormones. ABAs and SAs are shock hormones. All three types of hormones are similar in that they fall within the classic definition of an intercellular hormone. They are made by a cell and are meant to affect the behavior of other cells, either in nearby tissue or at the opposite end of the plant.

ABA, also known as abscisic acid plays a direct role in dormancy release and germination. Ethylene and the gibberellins group of hormones are indirectly involved.

HORTICULTURAL CLASSIFICATION OF PLANTS

The Horticultural crops are majorly classified on the basis of its consumption and uses as fruits, vegetables, flowers, spices, medicinal, aromatic and plantation crops. Moreover, these crops have been further classified into various groups on the basis of their habitat, growth pattern, edapho-climatic requirements and uses. All branches of horticulture classified specifically as hereunder:

A Classification of fruits

1. Based on Climatic adaptability
   1. Tropical fruits: These fruit crops are grown in tropical climatic regions which are geographically located between the parallels of 23° 27' South (Tropic of Capricorn) and 23° 27' North (Tropic of the Cancer) of the equator. They are generally evergreen and very sensitive to cold. Eg. Mango, Pineapple, Banana, Papaya, Citrus, Sapota, Avocado etc.
   2. Sub-tropical fruits: Fruit crops are grown in between temperate and tropical climatic regions. They may be either deciduous or evergreen nature. Eg. Mango, guava, citrus, durian, jackfruit, bread fruit etc.

1.1 Introduction

The word ‘horticulture’ was first used in 1600’s, and is derived from two Latin words, ‘hortus’(garden) and ‘cultûra’(cultivation), and it means ‘the culture (cultivation) of garden plants’. Relf (1992) defined “horticulture as an applied science and art of growing fruits, vegetables, herbs and spices, nuts, tubers, aromatic and medicinal plants, plantation crops, mushrooms and ornamental plants which include shrubs, flowering plants and turfs stimulating minds, spirits and emotions of individuals, enriching health and wellness of communities, and linking human beings to nature and its landscaped exteriors for wellness and wellbeing”. Fruits and vegetables are nourishing and protective foods. It has been recognized that fruits are a rich source of antioxidants which protect us from dreadful diseases. Vegetables and fruits contain vitamin E, K, and  carotene in addition to minerals like zinc, copper and manganese. To meet the ever-increasing demand of the country for fruits, vegetables, tubers, spices, flowers, ornamentals etc., we must strive hard to deliver better cultivars in as many aspects as possible to the society so that human beings will be in sound health physically as well as mentally. To achieve this goal plant breeding in general, and horticultural plant breeding in particular will come to our help.

Horticulture is an art and science of growing plants. It is the practice of engaging ailing people in various horticultural activities such as gardening and flower arrangements in order to improve their physical, mental and spiritual health. Research confirms that health benefits escalate manifold when people connect with nature and plants by viewing and/or interacting with them. Major benefits of horticultural therapy includes sensory simulation and mood enhancement, mental relaxation, improvement of memory and concentration and an overall feeling of wellness. Horticulture therapy also helps in cultivating positive emotions and provides a meditative mood. It eases both physical and emotional pains and also improves social skills. It is proven that a simple viewing of a garden benefits a person both physically and mentally.

This practice has been used as therapy for centuries. In 1798, Dr. Benjamin Rush, considered as the “Father of American Psychiatry” documented that gardening has positive effects on mentally ill patients. Following World War, II gardening was used as a form of occupational therapy for war veterans. The concept of using nature to improve human health began to gain credibility in 1970’s. Rachel and Stephen Kaplan (1989) found that natural environments had relaxing and restoration benefits for people. The Journal of Therapeutic Horticulture, a peer-reviewed publication of the American Horticultural Therapy Association, has published authentic research papers since 1986. The American Horticultural Therapy Association (AHTA) serves to promote and advance horticultural therapy as a therapeutic intervention and rehabilitative approach. Degrees and certificate programs in horticultural therapy are offered at several colleges and universities and information is available on AHTA website.

Horticultural therapy is a worldwide practice and recognized as an effective treatment for clients of all ages and abilities. It is being used in several diverse settings including hospitals, rehabilitation centres, youth outreach and recovery programs, nursing homes, senior care facilities, prisons, mental health facilities, schools, botanical gardens etc. The client is engaged in horticultural activities facilitated by some trained therapists to achieve specific and documented goals. AHTA believes that horticultural therapy is an active process that occurs in the context of an established treatment plan where the process itself is considered as the therapeutic activity rather than the end product.

Horticulture therapy is a growing profession in rehabilitation and addiction centers, vocational centers, youth mental health programs, hospitals and nursing homes, and old age homes or senior citizen centers, mental health centers, schools and colleges.

The Indian subcontinent is bestowed with a great variety of climate and soil conditions. Broadly the country can be divided into tropical, subtropical and temperate regions, within each broad category there are differences due to rainfall, humidity, altitude etc. Considering these aspects six different horticultural zones have been identified so that appropriate choice of the crops can be made and development is planned. They are;

Temperate: Kashmir, Himachal Pradesh, North Uttarakhand, Sikkim and part of Arunachal Pradesh.

N.W. Subtropical: Punjab, Haryana, Rajasthan, Central Uttar Pradesh and North Madhya Pradesh.

N.E. Subtropical: Bihar, Jharkhand, Assam, Meghalaya, Nagaland, Manipur.

Central tropical: South Madhya Pradesh, Chhattisgarh, Gujarat, Maharashtra, Orissa and West Bengal.

Southern tropical: Karnataka, Andhra Pradesh and Tamil Nadu.

Coastal tropical humid: Konkan, Goa, Kerala, Western Ghats, Eastern Ghats in Tamil Nadu, Andhra Pradesh and Orissa.

The Horticultural crops show wider adaptation and therefore exact delineation of the agro-climatic areas specific to each crops is not possible, except for the typical temperate and tropical species. However, our country can be broadly divided into seven zones for horticultural crops as indicated below:

1. Temperate Northern Region

Comprising of states of Jammu & Kashmir, Himachal Pradesh, Hilly areas of Uttar Pradesh and West Bengal. Temperate fruits, cool season vegetables are the important horticultural crops in the zone.

2. North Western Arid Region

Comprising ofthe entire Rajasthan state, Gujarat and parts ofPunjab & Haryana. Arid fruit crops like ber, pomegranate, amla, date palm, wood apple and seed spices like coriander, cumin, fennel occupy major area in this zone.

3. North Eastern Sub-tropical Humid Region

Comprising of states and union territories like Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland and Tripura. Fruit crops like banana, pineapple, citrus, jack besides plantation crops like tea and large cardamom are also grown here.

The Indian arid and semi-arid regions are characterized by immature, structure less, coarse textured soils with low water holding capacity and poor nutrient status. The moisture deficit conditions dominate for a long time throughout the year, which acts as the major limiting factor for establishment and growth of woody plant. Due to harsh edapho-climatic conditions, arable crop production is risky in arid and semi arid regions and threatening the agriculture, under such situation, horticulture based cropping system is considered effective strategy for improving productivity, employment oppornitues and nutritional security. Most of the cropping systems operating in the limited irrigated    area of arid ecosystems have very high water requirement and are highly unsustainable, hence location specific models have to be developed involving fruit crops, multipurpose tree species and arable crops in an agri-silvi-horti production system for increasing irrigation water use efficiency (IWUE), productivity, profitability and sustainability of the system. An attempt has been made to present the status of available research data on some of horticulture based farming systems for arid and semi arid regions

Fruits and vegetables play an important role in balanced diet. These provide not only energy rich food but also provide vital protective nutrients/elements and vitamins. Comparatively fruits and vegetables are the cheapest source of natural nutritive foods. Since most of Indians are vegetarians, the incorporation of horticulture produce in daily diet is essential for good health. Realizing the worth of fruits and vegetables in human health, Indian Council of Medical Research (ICMR) recommended the use of 120g fruits and 300g vegetables per capita per day. With the growing awareness and inclination towards vegetarianism worldwide the horticulture crops are gaining tremendous importance.

Functions of fruits and vegetables in human body

Fruits and vegetables provide palatability/taste.

Improves appetite and provides fiber to overcome constipation.

They neutralize the acids produced during digestion of proteins and fatty acids.

They improve the general immunity of human body against diseases, deficiencies etc.

They are the important source of vitamins and minerals for used in several bio-chemical reactions occur in body.

German Prof. Peter Laurenberg conceived first the word horticulture. The term “Horticulture” is known in written form first in seventeenth century in a book entitled “New World of Words” by Phillips.

Etymologically the word “Horticulture” is derived from two Latin words viz. ‘Hortus’ [garden or enclosure] and ‘Cultura’ [cultivation]. So, literally horticulture means ‘garden or enclosure culture’ or ‘cultivation of garden crops within protected enclosures’.

Garden: Garden is a broad term derived from the Latin word Gyrdan meaning “to enclose”.

DIVISIONS AND DEFINITION OF HORTICULTURE

Pomology: (pomum = fruits, logy = science) It is a branch of horticulture which deals with study or cultivation of fruit crops starting from raising of saplings and intercultural to harvesting operations. The ‘pomology’ term is derived from latin word pomum (means fruits) and greek word logy (means science).

Abstract

Deserts cover about one fifth of the earth’s land surface. Most of hot and dry deserts are near the Tropics of Cancer or the Tropics of Capricorn. Cold deserts are near the Arctic part of the word. Deserts are of two types: Hot and Cold. Some of the important among them are given in Table 1. Spread over an approximate area of 74,809sq km, the cold desert area in India covers 12 out of 131 desert blocks. Leh and Kargil districts of Ladakh in Jammu and Kashmir and Lahual and Spiti along with some part of Chamba and Kinnaur districts of Himachal Pradesh comprise this cold desert area (Fig 1). Similarly, their physiographic location and the consequent geomorphic processes shall unfolding in the region lend to this entire region a largely similar texture. In terms of area, the cold desert of Spiti may be too tiny as compared to the seven major cold deserts of the world (Table 1), but in terms of its high mountains, extreme climate and poor economic conditions of the people, it is one of the most scourged areas on the earth. Located in the interior of continents, away from any source of moisture, cold desert manifest resemble ecological verity and biological diversity. Their geographic remoteness and unfriendly climatic conductions greatly constrain economic growth and development. Envirmental degradation, which is on increase, is an additional cause of concern.

India is the seventh largest country in the world with a total geographical area of 328.73 million ha and has second largest population after China. The gross cropped area is 198.36 million hectares of which 70% is under rainfed cultivation. Around 55 to 60 per cent of the total population depends on agriculture and allied activities.

One of the important features of India prevalence is varied agro-climatic conditions; which enables to strengthen the horticulture industry. Many numbers of horticultural crops namely fruits, vegetables, ornamental and flower crops, spices and condiments, plantation crops, aromatic and medicinal plants, etc. are grown in almost all the parts of country. Thus, horticulture sector has become one of the major drivers of growth in agriculture having major share in agriculture GDP.

The Indian subcontinent is bestowed with a great variety of climate and soil conditions.

• Broadly the country can be divided into Tropical, subtropical and temperate regions.
• Within each broad category there are differences due to rainfall, humidity, altitude etc.
• Considering these aspects six different horticultural zones have been identified so that appropriate choice of the crops can be made and development is planned. They are;
• Temperate: Kashmir, Himachal Pradesh, North Uttarakhand, Sikkim and part of Arunachal Pradesh.
• N.W. Subtropical: Punjab, Haryana, Rajasthan, Central Uttar Pradesh and North M.P.
• N.E. Subtropical: Bihar, Jharkhand, Assam, Meghalaya, Nagaland, Manipur.
• Central tropical: South Madhya Pradesh, Chattisgarh, Gujarat, Maharashtra, Orissa and West Bengal.
• Southern tropical: Karnataka, Andhra Pradesh and Tamil Nadu.
• Coastal tropical humid: Konkan, Goa, Kerala, Western Ghats, Eastern Ghats in Tamil Nadu, Andhra Pradesh and Orissa.

After independence, the Government of India realized the need of diversification in agriculture during the mid-eighties with an objective to make it more profitable through efficient land use. Due to diverse agro-climatic conditions, rich diversity in genetic resources of horticultural crops, sincere efforts through education and research, implementation of standardized technology by horticulturist in the field has achieved not only the production, productivity and export of horticultural produce but also the food and nutritional security. Such horticulture development in India is proudly said as “Golden Revolution”. Horticulture is also said to be a sunrise industry as it has potential to raise farm income, provide livelihood security and earn foreign exchange through export.

The horticulture industry is now expanding in many commercial sectors such as cultivation, production, post-harvest handling, processing, marketing, etc. Horticulture crops are grown on an area of 10% of India’s gross cropped area, as compared to over 50% of the area under food grains production. 

1. IMPORTANCE

India is bestowed with a varied agro-climate, which is highly favourable for growing a large number of horticultural crops such as fruits, vegetables, root tubers, ornamentals, aromatic plants, medicinal herbs, spices and plantation crops like coconut, arecanut, cashew and cocoa. It has emerged as an indispensable part of agriculture, offering a wide range of choices to the farmers for crop diversification. It also provides ample opportunities for sustaining large number of agro-industries which generate substantial employment opportunities. India has emerged as the second largest producer of fruits and vegetables; with largest producer of coconut, arecanut, cashew, ginger, turmeric, black pepper and tea, among plantation crops.

The changing scenario encourages private investment, to go for Hi-tech Horticulture with micro-propagation, protected cultivation, drip irrigation, fertigation and integrated nutrient and pest management, besides making use of latest post harvest measures particularly in the case of perishable commodities. As a result, horticulture crop production has moved from rural confines to commercial ventures and has attracted youth since it has proved to be intellectually satisfying and economically rewarding. It is essential to appreciate the contribution of horticulture, landscaping and gardening in the hospitality industry. Aesthetic use of horticulture freshens up the atmosphere, enhances the look of the property and creates a lasting impression on guests. It also has a beneficial effect on the health.

To reduce the dependence on hazardous pesticides in modern agriculture, one of the most promising ways is to use insect-resistant cultivars. When available, planting resistant cultivars is one of our most effective, economically viable and environmentally sound tactics. The underlying concept of using host resistance to our advantage comes from the knowledge that most plants and animals are resistant to most potential insect attackers.