eChapters

11.1 INTRODUCTION

Plant growth regulators have remained an important component in horticulture from time immemorial because they were effective means of quantitative as well as qualitative improvement in growth and development of crops. Plant Growth Regulators (PGR) are diverse group of organic compounds other than nutrients, produced artificially or by plants which in low concentrations promote, inhibit or modify the physiological process in plant. The term includes both naturally occurring phytohormones as well as synthetic compounds. These are produced naturally in higher plants, controlling growth or other physiological functions at a site remote from its place of production and active in minute amounts. Plant Growth Regulators are used in different forms like liquid, powder, paste etc. “Hormone” is Greek word derived from “hormao”, which means to stimulate. Thimone (1948) suggested the use of term ‘phytohormones’ as the organic substance, which are produced naturally in plants, synthesised in one Part And usually translocated to other part wherein every small quantity affects the growth and other physiological function of the plants. To distinguish them from the animal hormones they are termed as phytohormones. Auxin was the first hormone to be discovered in plants and at one time considered to be only naturally occurring plant growth hormone. The role of plant growth regulators in various physiological processes such as seed germination, f lowering, fruiting, seed development, fruit ripening and yield etc. in different crop plants is well established (Kiran et al., 2011). There are five classical phytohormones: auxins, gibberellins, cytokinins, ethylene and abscisic acid. Besides classical phytohormones a variety of other compounds that play roles in plant growth and development have also been identified, including jasmonic acid, salicylic acid, brassinosteroids and polyamines (Basra, 2000). The application of plant growth regulators in agriculture has started in 1930 in the United States. Ethylene, a naturally occurring substance, is one of the first plant growth regulators being discovered and used successfully for enhancing f lower production in pineapple (Fishel, 2006). Its toxic effects to human beings are low.

10.1 INTRODUCTION

Most botanists identify trees by their leaves, f lowers and fruit. However, the plant architecture specialist is interested in trunks, branches and twigs. All types of fruit tree do not require pruning, e.g., mango, sapota, while some fruit trees can grow well naturally, e.g., pineapple, papaya as they do not require pruning. Most deciduous trees like apple, pear, almond etc. and grapes, ber, fig, citrus, pomegranate, guava etc. require pruning to train them for desired shape.

10.2 TRAINING

Training is an operation by which the plant is made to develop an orderly structure or frame work. This is done by staking, tying, supporting, propping, trailing or spreading on certain structure with or without pruning of plant. Training is usually done when plants are young. Bending, twisting, decapitations are done by using springs of hard wire, where it is required. It is a physical technique which controls the shape, size and direction of plant growth known as training or in other words, training in effect is orientation of plant in space through techniques like tying, fastening, staking, supporting over a trellis or pergola in a certain fashion or pruning of some parts.

9.1 INTRODUCTION

Establishment of an orchard incurs long term investment for which it needs a very critical planning. As it is a long-term investment, plants planted in the orchard should suit to the prevailing climatic condition of that area. The land remains occupied as long as 40 to 50 years. Any mistake committed during initial year is hard to rectify later on. Proper layout of the orchard ensures optimum utilisation of land and resources for successive economic production. It becomes easy for different inter-cultural operations, harvesting and transportation of the produces. Uniform distribution of plants in the selected land in various systems of planting is done after proper layout.

9.2 LAYOUT

The proper layout of orchard aims at accommodating maximum number of trees per unit land area, maintaining adequate space for proper development of the trees and convenient orchard management practices.

8.1 INTRODUCTION

Orchard is a place or a piece of land where different kinds of fruit plants are planted in orderly manner and managed efficiently for production of successive yield to get assured economic return. An orchard being capital-intensive and long-term venture careful planning, layout, selection of site, preliminary operations etc. are to be done. It is easy to establish an orchard considering its features critically but difficult to manage afterwards. It needs high managerial skills and technically skilled manpower to carry out different orchard operations. Any lapses in management can lead to incur heavy loss.

7.1 INTRODUCTION

Gardening is a practice of growing different kinds of horticultural crops in a particular land area as a part of horticulture either for consumption or sale, export, beautification etc. Basing on the crops grown, gardens are named accordingly, e.g., for raising vegetables, it is vegetable gardens; for fruit crops, it is orchard; for plantation crops, it is estate plantation; for ornamental plants, it is gardening and landscape etc. The history of gardening is not new. In ancient time kings, emperors, rulers, sages were establishing different types of gardens for different purposes.

6.1 INTRODUCTION

The Climate and soil play important role in growth and development of the plant. Growers in general and fruit growers in particular should have adequate knowledge of the effect of various soil and climatic conditions on raising horticultural crops. Horticultural crops cannot be grown in all types of soil and climate. Hence zone- wise cultivation is made. Climate includes a number of parameters like temperature, rainfall, atmospheric humidity, wind, hail and light whereas soil covers factors like moisture content, texture, soil reaction, nutrient content, chemical composition and soil temperature.

6.2 SOIL

Soil is a thin outer covering of the earth surface. It is the natural resource directly developed by different natural forces acting on natural materials. Soil serves as a base and support for plant growth. It is a basic medium for plant growth and supplies nutrients for growing plants. Soil is the home of the plant root and the reservoir for essential nutrients and water for growth and development of crop plants.

5.1 INTRODUCTION

The importance of the best quality planting material as an initial investment is a well-realized factor for persons engaged in horticulture field. So, nurseries have great demand for the production of plants, bulbs, rhizomes, suckers and grafts. But in general, good quality and assured planting material at reasonable price is not available many a times. Nursery is the basic need of horticulture. Plant propagation techniques and practices is the core of horticulture nurseries. The planting materials for horticultural plantations are raised from seeds and vegetative parts. The difficulty of procuring tree seeds and their rising cost makes it necessary to find means to increase seedling survival and growth.

Raising a nursery needs a great skill. Nursery business has become an agro- business for the unemployed youths. Generally, various commercial crop growers require a good quality saplings or grafts of genuine type. So, nursery raising is quite a remunerative enterprise.

Nursery is a special place where seeds are sown, plants are propagated, grown, nurtured to usable size for planting or for sale. Nurseries provide the necessary control of moisture, light, soil and predators and allow production of healthy and hardy seedlings.

4.1 INTRODUCTION

India enjoys a wide range of climates and agro-meteorological zones which are suitable for growing various kinds of horticultural crops like fruits, vegetables, f lowers, spices and condiments, plantation crops, and medicinal and aromatic plants.

India is the largest producer, consumer and exporter of spices in the world. India stands second both in production of fruits and vegetables next to China. China contributes 21.2% in the world fruit production whereas India produces 12.6%. When we think of vegetables, China produces 49.5% and India produces 14.09%. India is the largest producer of Mango, Banana, Papaya, Coconut, Arecanut, and Cashewnut in the world. In the country, Andhra Pradesh (13.0%) is the leading state in fruit production followed by Maharashtra (11.2%). In case of vegetables, Uttar Pradesh stands first occupying 15.1% share followed by West Bengal and Madhya Pradesh in the range of 14.6% and 10% respectively. In cut flower production West Bengal ranks first.

Total horticultural production for the year 2017–18 was 311.71 million tonnes from cropping area of 25.43 million hectares of land and an estimated production for the crop year 2018-19 is 314.87 million tonnes from an area of 25.6 million hectares.

3.1 INTRODUCTION

Life cannot be sustained without adequate nourishment. Human beings need adequate food for growth, development and to lead an active and healthy life. Animals satisfy basic food requirement mainly through natural selection. But human beings have access to a wide range of foods to choose to make up their diet. Since all foods are not of same quality from nutritional point of view, man’s ability to meet his nutritional need and maintenance of good health depend upon type and quantity of foods he is able to include in his diet to satisfy hunger. Human beings need a wide range of nutrients to perform various functions in the body and to lead a healthy life. Several reports have shown that adequate intake of fruits and vegetables forms an important part of a healthy diet and low fruit and vegetable intake constitutes a risk factor for chronic diseases such as cancer, coronary heart disease (CHD), stroke and cataract formation. The nutrients include proteins, fats, carbohydrates, vitamins and minerals. The foods containing these nutrients which we consume daily are classified as cereals, legumes, nuts and oil seeds, fruits, vegetables, milk and milk products and f lesh foods like fish, meat and poultry. Some foods provide only a single nutrient and some multiples. Scientific evidence indicates that frequent consumption of fruits and vegetables can prevent oesophageal, stomach, pancreatic, bladder and cervical cancers and that a diet high in fruits and vegetables could prevent 20% of most types of cancers. Reports indicate that increasing individual fruit and vegetable consumption by 600 g per day could reduce the global burden of stroke by 19% and decrease the risk of coronary heart diseases by 31% respectively. Realizing the food value of fruits and vegetables in human nutrition the Indian Council of Medical Research (ICMR) recommends per capita use of 120g fruits and 280g vegetables per day.

2.1 INTRODUCTION

Owing to a varied agro-ecological and eco- edaphic condition prevalent in one or other part of the country, quite a large number of crops are grown in different parts of India. India is rich in bio-diversity with four hotspots out of twenty-five in the world. About 356 domesticated plant species having economic and botanical importance and 326 species with their wild relatives are found in Indian sub-continent. Besides the above, 9500 other plant species are also available. More than 50 different types of fruits, 50 different types of vegetables, 95 types of spices and condiments, medicinal and aromatic plants, plantation crops and ornamental crop plants have been recorded. To avoid confusion and identity, the horticultural plants are grouped into different categories based on similarity or dissimilarities. Grouping of the crop plants with similar characteristics is referred as classification.

1.1 INTRODUCTION

India is the seventh largest country in the world in total geographical area and has second largest population next to China. Around 55 to 60 per cent of its population depend on agriculture and allied activities. Horticultural crops constitute a significant component of total agricultural production in the country. They require very intensive care in planting, carrying out different cultural operations, manipulating growth, harvesting, packing, transportation, marketing, storage and processing.

1.2 AGRICULTURE

The term agriculture broadly refers to the technology of raising plants and animals. Agriculture is the science, art or practice of cultivating soil, producing crops and raising livestock in varying degree of proportion followed by marketing. In other words, it is the activity of man to produce three basic needs of human being, i.e., food, fuel and fibre (3F) by using terrestrial resources optimally. The term agriculture is derived from two Latin words ager meaning field or land and cultura meaning cultivation or growing.

Organic certification is the procedure by which the accredited certification Body by way of a Scope Certificate assures that the production or processing system of the operator has been methodically assessed and conforms to the specified requirements as envisaged in the National Programme for Organic Production (NPOP).

The NPOP provides for Standards for organic production, systems, criteria and procedure for accreditation of Certification Bodies, the National (India Organic) Logo and the regulations governing its use. The standards and procedures have been formulated in harmony with other International Standards regulating import and export of organic products.

In last few decades awareness about social and environmental issues has been increased. Agriculture is one of basic enterprise that has major role in these two issues . Organic agriculture is one of the agriculture production system that not only supportive to the environment but also sensitive to the social issues like employment, health, migration etc. Definitions given by two international organizations also verify this concept.

Over 85% of the rural population in India is dependent on agriculture for their livelihood. About 50% of them being poor, most of their earnings are spent on meeting their basic needs, particularly food. With the increasing population over the last five decades, their per capita share of land and water resources has reduced substantially. As a result, rural people are faced with the problem of unemployment.

Inspite of agriculture being a major source of livelihood, the productivity as well as profitability in agriculture have been significantly low in the country. While the productivity can be attributed to illiteracy, lack of awareness, poor dissemination of technology, inadequate investment in agricultural inputs and poor communication and information services, lack of profitability is mainly due to inadequate and inefficient infrastructure required for forward and backward integration, poor post harvest and processing facilities and poor connectivity with market, resulting in exploitation by large number of middlemen. Traditionally, the farmers have been dependent on the Agricultural Extension Agencies of the State Government for information, input supply and marketing services. Over the years, these agencies are not being able to cope up with the growing responsibilities and specific needs of the farmers. To overcome this problem, Farmers’ Cooperatives have been promoted to supply various agricultural inputs and organise the marketing of farm produce. Although, this was an excellent concept, most of these cooperatives could not carry out the work economically and efficiently due to lack of commitment from the elected leaders and unfair trade practices by the competing traders. The farmers, not realising the inability of the extension agencies, are still dependent on the Government and external agencies to help them in managing their agri-business.

Heifers are future cows of the herd. Production and reproduction performance of cows depends on the care and management during calf and heifer stage. Rearing period of heifers can be divided into two stages, viz. from weaning to first service and service to calving.

Care of calf before birth

During the last 2-3 months of gestation the fetus grows rapidly. Calf draws a significant quantity of nutrients from the mothers system. It has to be replenished by additional feeding of the cow. A cow should be fed well-balanced ration for maintenance.

Fruits with their delightful colours, flavours and tastes are nature’s wonderful gift to mankind. Apart from being the most nutritious food in the form of easily digestible simple sugars, vitamins, minerals and many phyto-nutrients (Plant derived micronutrients), they provide unique health benefits due to their antioxidant properties and valuable fibre. Antioxidants help protect the human body from oxidant stress, diseases, and cancers, and also boost the immunity of the body thus developing the capacity to fight against various types of diseases. The insoluble dietary fiber in fruits is known to provide protection from conditions like chronic constipation, hemorrhoids, colon cancer, irritable bowel syndrome, and rectal fissures etc. Due to their unique nutrition-profile the importance of fruits in our diet cannot be over emphasised.

Insects are a major limiting factor in fruit production. The infestation of insects pests on fruit trees in orchards adversely affects the quality and yield of fruits. The size, shape, taste, attractiveness and palatability of fruit deteroriates, due to which the market price is reduced and the growers incur losses. Fruit growers resort to use of chemical pesticides under such conditions. However many reports suggest that although the global production and use of pesticides in agriculture is increasing every year, but the damage due to insects has not decreased rather it has also increased, indicating that the use of pesticides is not the panacea remedy for all insect related problems. Many scientists are of the opinion that over-reliance on the use of synthetic pesticides in crop protection programs around the world has resulted in disturbances to the environment, pest resurgence, pest resistance to pesticides, and lethal and sub-lethal effects on non target organisms especially beneficial flora and fauna, including humans. Farmers spend thousands of rupees on pesticides. The residues of pesticides in food and fruits is yet another cause of concern. Fruits which are considered to be wonderful for health are often laden with unacceptable levels of pesticide residues nulling their beneficial properties. Pesticides have been linked to many diseases especially cancer. All these issues related with use of pesticides has triggered rethinking on the methods of control.The recent examples of the results of indiscriminate pesticides use , consequent crop failures and suicide by farmers now calls for introspection in this matter.

Importance of fruits in human diet is well recognized since time immemorial. They are important part of a healthy diet as natural sources of energy, essential vitamins, minerals and antioxidants ever since the beginning of humancivilization. Our country is bestowed with varied climatic conditions, which had made it possible to grow diverse group of fruits from its temperate to tropical, to subtropical and even to arid niches. The cultivation of fruit crops is, presently, one of the most important and profitable proposition. Growing fruit crops translate into realization of more yield/ income from a unit area of land than any of the agronomic crops. However, there is need to considerably increase the yield of fruit crops, particularly under changing environmental conditions as under such conditions diseases are getting more prevalent. Therefore by adoption of proper protection practices, yield of fruit crops can be improved.

Plant diseases caused by fungi, bacteria, viruses and phytoplasmas reduce crop yields (Khoury and Makkouk, 2010).Adoption and support for using participatory approaches help to farmers in disease management of fruit crops, reducing costs and improving production efficiency. Fungal, bacterial and viral diseases pose serious threat in the cultivation of fruit crops in India. To reduce the losses caused by plant disease, a complete knowledge of disease management strategies of fruit crops are essential which are as follows:

According to FAO estimates, about 50% total geographical area in India is under various degraded hazards and about 2.1 million ha of land is getting degraded and deforested annually (Sehgal et al. 1998). Out of that underground water in arid and semi-arid areas is saline or sodic in nature. While spices, medicinal and aromatic plants may be a boon for these areas, which not only withstand under adverse conditions but also could be productive and helps in mitigating these problems. However, other crops are remain less or unproductive in these areas.

Spices are low volume and high value crops and have tremendous export potential, which is witnessed by several invasions faced by this Indian peninsula during ancient time. Medicinal and aromatic plants have an equally market potential with the world demand of herbal products growing at the rate of 7 per cent per annum (Aishwath and Tarafdar, 2007). Seed spices and aromatic plants are the natural source of flavour, perfumes and fragrance widely exploited by essential oil industries in the world. Owing to considerable diversity of edaphoclimatic conditions ranging from temperate to tropical and arid to sub- humid that prevails in India and an array of medicinal and aromatic flora occurs in wild state. Many exotic essential oil bearing plants, including mints, citronella, geranium, patchouli, lavender and chamomile have been naturalized in India. As the country has emerged as one of the main producers of seed spices and some of the essential oils, theses plants are significant foreign exchange earners. Some of the aromatic plants especially grasses can sustain both biotic as well as abiotc stresses, even in the areas unsuitable for conventional crops (Aishwath et al., 2008). Most of the seed spices crops are seasonal crops and comes up well with limited moisture and nutrients. Therefore, under utilized natural resources can be utilized profitably by crop diversification.

The arid region of India covers about 12 % of countries geographical area and occupies over 3.17 lakh Km² of hot desert located in the parts of Rajasthan (61%), Gujarat (20%), Punjab and Haryana (9.0%), Andhra Pradesh (7%), Maharashtra (0.4%) and Karnataka (3.0%). In addition to this an area of about 78 thousand Km² of cold desert in Jammu & Kashmir and Himachal Pradesh presents an entirely different set of agro climatic conditions as compared to hot arid zone. The hot arid region is characterized by low and erratic distribution of rainfall (< 100 to 400 mm), high temperature, low relative humidity, high potential evapo-transpiration, high sunshine and high wind speed during summer. Soils of this region are dry for most part of the year and suffer from water stress. Besides growing annual crops, a great emphasis is being laid on the development of agroforestry systems in this region which also includes cultivation of arid fruit crops in cropping systems. Horticulture based production systems are considered to be the most ideal strategy to provide food, nutrition and income security to the people (Chundawat, 1993). Integration of annual crops with fruit trees yields multiple outputs that ensure production and income generation.

Global climate changing has been a focus for a long time in many fields, the increasing CO₂ concentration in atmosphere was considered as one main driving force for global warming. The increases in greenhouse gasses in the atmosphere contributed to raise concerns over climate change enhanced the role of forests and plantations in the global carbon cycle are growing as a great issue. Carbon dioxide (CO₂) is one of the main greenhouse gases because a huge volume of CO₂ is added to the atmosphere, when compare to all other greenhouse gases and made itself as a primary agent of global warming. It contributed 72 per cent of the total anthropogenic greenhouse gases, causing between 9-26 per cent of the greenhouse effect (Kiehl and Trenberth, 1997). According to the Intergovernmental Panel on Climate Change (IPCC), there has been an unprecedented warming trend during the 20th century. Scientists now have estimated that the average global surface temperature is likely to rise by 1.4 to 5.8°C by the end of the 21^st century (IPCC 2007).

The IPCC estimates that the level of carbon dioxide in today’s atmosphere is 31 per cent higher than it was at the start of the Industrial Revolution about 250 years ago. An atmospheric level of CO₂ has risen from 280 ppm at the pre-industrial to the present level of 375 ppm. Most of the increase has occurred in the second half of the 20^th century. The mitigation of climate change demands, determined commitment of scientists to develop strategies to effectively manage the issues of the changing climate through carbon sequestration. Carbon sequestration is ought to be a promising solution for reducing atmospheric carbon dioxide, an important greenhouse gas.

Energy and food are the two main requirements for human civilization; however the demands for these two resources are increasing in a fast rate. Development of any region is reflected in its quantum of energy consumption. In this context, the situation in arid region is difficult. People burn firewood, agricultural waste and cow dung cake for cooking food causing damages to the fragile eco-system of arid zone. There is inadequate electrical power supply and hence villagers of remote arid areas are unable to derive general benefits. The kerosene is used for lighting and fast depleting diesel oil is used for running agricultural machinery including pumps. In this context solar energy is considered to be one of the promising sources in India.

About 12% of electricity production capacity in India is met through renewable energy sources. In India, national solar mission was launched in November 2009 with a target of 4000 MW grid and 1000 MW off-grid electricity generation from solar energy by the end of phase II (2013-2017), whereas these targets are 20,000 MW and 2000 MW, respectively by 2022. The target has been revised in 2015 to a total grid connected solar power generation of 1,00,000 MW comprising of 40,000 MW roof top generation and 60,000 MW grid connected solar power plants (Resolution of MNRE, Govt of India, No. 30/80/ 2014-15/NSM dated 1^st July 2015).

Increasing susceptibility of vegetables to various biotic and abiotic stresses and very high cost of hybrid seeds has warranted the attention of the vegetable growers to improve the nursery raising technology of vegetables. Now-a-days protected nursery raising of vegetables has become a full flagged industry in several developed countries like Israel, Japan, Spain, Netherlands, USA etc. In countries like Israel no vegetable grower is growing his own nursery, but they are getting the required kind of seedlings from an established nursery owner on pre- order basis. Similar system of nursery raising is also prevalent in several other advance countries. In those situations where vegetables are being grown under protected conditions it becomes pre-requisite to raise the required vegetable seedlings only under protected environment to get virus free healthy seedlings.

Raising nursery from seeds provide an easy and convenient way to nourish tender and young seedlings in a well managed, small and compact area for better germination of small and costly seed. In general, vegetables crops are divided into three groups according to their relative ease for transplanting. Beet root, broccoli, brussels sprouts, cabbage, cauliflower, tomato and lettuce are efficient in water absorption and rapidly form new roots after transplanting. Vegetables crops that are moderately easy for transplanting are brinjal, onion, sweet pepper, chilli and celery which do not absorb water as efficiently as crops that are easy to transplant, but they form new roots relatively quickly. The vegetable crops which are difficult to transplant are: all cucurbits and sweet corn which require special care during nursery raising and transplanting. Seedlings not only reduce the amount of time of the crop but it also increases the uniformity of the crop and harvesting as compared to direct sowing of the crops. Transplanting of seedlings also eliminates the need for thinning and provides very good opportunities for virus free, vigorous and even off-season seedlings if grown under protected conditions in soil-less media. So it becomes necessary to know the protected structures which can be efficiently used for successful raising of vegetable seedlings, suitable types of containers and growing media, method of seeding in containers in soil-less media, growing conditions and water and fertilizer requirement of seedlings along with hardening and transplanting to the field. Protected nursery raising technology is highly suitable and can be established as a small scale industry in major vegetable growing areas of our country by progressive farmers especially in peri-urban areas. By this way the vegetable growers will get virus-free healthy and off season nursery as per their requirement and it generate extra employment in rural areas.

In the present scenario of rapidly increasing population and decreasing cultivable land, there is urgent need to increase the agricultural productivity. According to Indian Council of Agricultural Research (ICAR), 280 million tones food grain would be required to match the country’s demand by 2020. It will be a difficult task to meet this food requirement in near future from the present productivity levels. It is necessary to increase agricultural productivity, because about 60% of Indian agriculture is rainfed. Proper use of even a single drop of rain water is necessary to ensure the success of rainfed agriculture. In hills, agriculture is main source of livelihood of rural people. However, small and scattered land holding, difficult topography, womendependent agriculture, totally rainfed, typical socio-economic factors and migration of youth towards urban/plain areas are major constraints of hill horticulture.

In the high altitude areas, the river flow in deep valley at the toe of slopes rarely serve any purpose as far as domestic water supply and irrigation are concerned and hence, agriculture in these areas is mostly rainfed. However, these areas received high magnitude of rainfall but this rainwater is not possible to convert into soil moisture due to steep terrain of hills which provided minimum opportunity time for infiltration of rainwater. It has been estimated that only less than 15 per cent of the rainwater is able to percolate down through slopes and recharge the soil moisture. The rainfall pattern hill is erratic i.e. most of rain (approximately 70% of annual rain) received only during the two months of monsoon. Furthermore, the climate of high altitudes comprises several climatic anomalies such as wide variability in temperature (-3 ^oC to 35 ^oC), frequent snowfall, hail, sleet and erratic pattern of rainfall. Under such abrupt conditions crops grown in open conditions could not be sustained.

Micro irrigation normally called as drip irrigation was introduced in early seventies. Drip irrigation is one of the advanced methods of irrigation, by which water can be supplied directly into the root zone of the soil to achieve considerable saving of water through high water use efficiency, compared to surface irrigation method where water use efficiency is low due to losses in the water distribution system in the field. In micro irrigation method, water supplied at slow rate that is 1.0-2.0 kg/sq cm to the root zone of an individual plant through lets called emitters or drippers fitted with laterals pipes and filters at pump side. The success of micro irrigation is proven and efforts are being made in promoting the same extensively among the farmers in arid areas.

The hot arid regions of India are spread over about 31.7 million ha area mainly in the States of Rajasthan, Gujarat, Andhra Pradesh, Punjab and Haryana, which inhabit on an average 61 persons per square km making up a population of nearly 20 million peoples. The Indian arid zone is characterized by high temperature and low and variable precipitation which limit the scope for high horticultural productivity. However, these conditions greatly favour development of high quality production in number of fruits such as date palm, ber, pomegranate, citrus, aonla, bael, grapes and, guava. The optimized technologies and inputs could increase the existing low productivity. It is now realized that there is a limited scope for quantum jump in fruit and vegetable production in the traditional production areas. The amelioration of the extreme conditions is also considered vital for life support to the inhabitants of this area. The recent awareness regarding the potential of these ecologically fragile lands for production of quality horticultural produce has not only opened up scope for providing economic sustenance for the people of this region, but also for bringing new areas to increase production through horticulture.

There has been an increasing demand for horticultural crops more particularly fruit .With this, the demand for good quality planting materials has gone up and hence the nursery business has developed rapidly in the recent years in our country. Plant propagation aims at the reproduction of selected individuals or group of individuals, in this the basic principal of life impose certain requirements which must be met with in practices for successful propagation. Plants material of various fruit crops have not only to be raised efficiently and scientifically, for which skilled knowledge in raising and management of nurseries is needed, but also these have to be transported quickly from nurseries to place where these plants materials will be grown.

Availability of quality planting material is one of the most importanant requirement for increasing the production and productivity of any fruit crops. It becomes one of the great challenges for horticulturists to get the disease free quality planting materials of fruit crops from an efficient and reliable nursery.

Sustainable development and efficient management of water is an increasingly complex challenge in India. Increasing population, growing urbanization and rapid industrialization combined with the need for raising agricultural production generates competing claims for water. Ground water has an important role in meeting the water requirements of agriculture, industrial and domestic sectors in India. About 85 percent of India’s rural domestic water requirements, 50 percent of its urban water requirements and more than 50 percent of its irrigation requirements are being met from ground water resources. Ground water is annually replenishable resource but its availability is non-uniform in space and time. Technically, the dynamic ground water refers to the quantity of ground water available in the zone of water level fluctuation, which is replenished annually. Hence, the sustainable development of ground water resources warrants precise quantitative assessment based on reasonably valid scientific principles. National Water Policy, 2012 has laid emphasis on periodic assessment of ground water resources on scientific basis. The trends in water availability due to various factors including climate change must also be assessed and accounted for during water resources planning. To meet the increasing demands of water, it advocates direct use of rainfall, desalination and avoidance of inadvertent evapo-transpiration for augmenting utilizable water resources. The National Water Policy, 2012 also states that safe water for drinking and sanitation should be considered as pre-emptive needs followed by high priority allocation for other domestic needs (including needs of animals), achieving food security, supporting sustenance agriculture and minimum eco-system needs. Available water, after meeting the above needs should be allocated in a manner to promote its conservation and efficient use.

Dry areas specially arid and semiarid regions are characterized by harsh climatic condition with limited natural resources like fresh water and vegetation. Soil which is most important component for agricultural production is also problematic in this region due to high salt content. Further, these regions face dual water problems: very low rainfall and poor quality of available water. Most of the available groundwater in these areas has high salt content, which further enhance salt content in soil after irrigation with this water. Salinity of soil is one of the most severe abiotic factors limiting agricultural production in arid and semiarid regions of the world. Term ‘salt-affected soil’ refer to soils in which salts interfere with normal plant growth, and is broadly divided into saline, saline- sodic and sodic soil, depending on amounts of salt, type of salts, amount of sodium present and soil alkalinity. Excessive soluble salts in the saline soil limit the ability of plant roots to absorb soil water even under wet soil conditions, while high sodium content in sodic soil reduce the availability of Ca, Mg, other micronutrients and finally deteriorate physical condition of soil. Poor physical structure of soil results in difficult to till, poor seed germination due to soil crusting and restricted plant root growth. Due to the poor physical structure, sodic soils are also susceptible to wind and water erosion compared to saline soils. All these negative impact of salt accumulation on the soil finally affect growth and yield of the crops. As per estimates of ICAR-Central Soil Salinity Research Institute (CSSRI), Karnal, crop production loss to country due to sodicity is around 11.18 million tonnes while due to salinity is around 5.66 million tonnes. Furthermore, the area under this category is rising due to secondary salinization caused by faulty management of irrigation water, seepage loss, impeded drainage, rapid rise of water table causing water-logging. Certainly, these soils and saline water threaten the livelihood security of farming community. The area under cultivation is decreasing due to diversion of agricultural land in to other uses to meet needs of rising population and as such, agriculture has to make best use of poor quality land and water resources to meet the food demand. Therefore, management of salt affected soil become necessary for ameliorating negative impact and enhancing agricultural production in these regions. Each type of salt-affected soil has different characteristics and thus required different strategies for management.

Global warming and climate change are becoming major challenges in the front of global community to deal with. Climate change is no more a myth but it is reality. The IPCC, 5^th assessment report clearly stated that “evidence of climate- change impacts is strongest and most comprehensive for natural systems”. Natural and human systems of almost all continents in the world have been affected by climate change in recent decades (IPCC, 2014). Agriculture is essential for sustainability of human life on earth but change in climate is threatening its sustainability. In recent decades all aspects of food security has been potentially affected by climate change, including food access, utilization, and price stability. It has been projected that in absence of adaptation measure, increases in local temperature by 2°C or more above late-20^th-century levels will negatively impact production of the major crops in tropical and temperate regions.

Agriculture is one of the major economic activities responsible for food security and livelihood for millions of people. Success, production and productivity of agricultural crops are highly dependent on climate, soil and water. Thus climate change will have adverse effect on agricultural crops. High atmospheric temperature, unpredicted erratic rainfall, rapid soil degradation and evolution of new insect and pests due to climate change will offer new challenge to sustain agriculture. Many part of the world and India is already experiencing impact of climate change on agricultural crops (like early maturity, geographical shift and occurrence of new pests) and these impacts are predicted to increase rapidly in future. The increasing concern about adverse impact of climate change on food security has led to extensive research and documentation of impact of climate change on field crops like rice, wheat and maize. While the clear and holistic idea about impact of climate change on horticultural crops like vegetables and fruits are not well documented especially in developing countries like India.

Biodiversity is a matter of concern to everyone as most of the economic sectors depends on it e.g. agriculture depends on it for wild genetic resources and biological control, human health depends on nature for many pharmaceuticals, industry requires raw materials which come from the nature, tourism increasingly base its attraction on natural amenities linked to biodiversity, water resources require intact vegetation to protect watershed and prevent siltation, disaster prevention needs natural vegetation to help people to respond to drought and the lists goes on and on (Mc Neely, 2004). Each of these sectors needs to be reminded of its reliance on biodiversity and provided with opportunity to invest in insuring the continued survival of the biological basis of their prosperity. Thus biodiversity has emerged as an integral aspect of human life and hence undoubtedly one of the keystone of sustainable development. Biodiversity in arid lands are under severe threats due to habitat destruction (Manuder and Clubbe, 2002), invasion of species (O’Kennen et al., 1999) dilution of customary conservation practices, climate change (Given, 1994; WCMC, 1992), increasing human population, unsustainable exploitation of natural resources, grazing pressure etc.

Indian hot arid zone which is about 12% of total geographical area of the landmass of 0.32 million km² has maximum covering in western Rajasthan i.e. 61% of the total area whereas the other areas in arid region are available in the states of Gujarat, Punjab, Haryana, Andhra Pradesh and Karnataka accounting for 20, 5, 4, 7 and 3% of hot arid area whereas the cold arid area of 8.4 million ha lies in the state of Jammu & Kashmir covering the Leh and Ladakh region.

The hot arid area is characterized by frequent droughts of 47% of frequency in the last century of moderate to severe nature. Due to higher occurrence frequency of droughts in this region of state, the livestock assumes great importance as a drought management measure as agriculture is at the mercy of rainfall pattern which is very uncertain in amount as well as distribution coupled with poor soil condition, higher evapotranspiration and higher wind velocity causing the soil erosion.

For arid region of Rajasthanthe general climatic conditions, topographical features and biotic factors do not encourage agricultural operations in the absence of extractive industry the peasantry has to fall upon animal husbandry as their main occupation. Rearing some of the finest breed of cattle, camel, sheep and goats known for their endurance making much use of the meagre feed resources which are grasses ,herbs, shrubs, tree leaves and cultivated feed and fodder crops. Livestock farming has some in built superiority over crop farming as far as growth; stability and resource conservation are concerned. On an average, the region experiences 3 years of drought in every 10 years. The natural forces constituting the soil-climatic complex, which conspire to reduce the crop productivity and cause instability in agricultural production, have much less impact on livestock farming. This is due to differences in the nutritive value of natural vegetation, which mainly sustains livestock.

Rainfed farming has a distinct place in Indian Agriculture, occupying 67% of the cultivated area, contributing 44% of the food grains and supporting 40% of the human and 65% of the livestock population. It is characterized by resource poor farmers, poor infrastructure and low investment in technology inputs (Singh, 1999). The land use in rainfed areas is quite diverse with a variety of crops, cropping systems, agroforestry and livestock farming. The productivity levels have remained low over the years and the share of rainfed crops in the total food grain production has been declining. The rainfed ecosystem suffers from the problems of (i) frequent droughts due to high variability in the quantum and distribution of rainfall, (ii) poor soil health due to continued degradation and inadequate replenishment of nutrient exhaustion, (iii) low animal productivity due to an acute scarcity of fodder and (iv) low risk bearing capacity of farmers due to poor socio-economic base, credit availability and infrastructure.

Of the total land area of the world, arid zones account for 18.8%. Throughout the arid zones, there is no dearth of problems, but rapidly increasing desertification (some call it land degradation) is a problem of worldwide dimension. Water is a scare commodity in arid zones. Much of rainfall is lost by evapo-transpiration and as a result, ground water recharged only by seepage through soil profile. However, it is a common phenomenon in arid zones of the worlds that ground water is frequently used at the rate that exceeds recharge. The situation in arid tropics of India, which is spread over an area of 31.7 million ha, is no more different.

Agriculture is the human enterprise that is most vulnerable to climate change. Tropical agriculture including agriculture in arid tropics, particularly subsistence agriculture is vulnerable, as farmers do not have adequate resources to adapt to climate change. Land-use options that increase livelihood security and reduce vulnerability to climate and environmental change are necessary. Rural folk in arid western Rajasthan, the principal hot arid region of the country have been practising arable cropping in association with these scattered trees on crop fields since time immemorial. This combined protective-productive system of integration of trees into farming system rooted in the principles of ecology, productivity, economics and sustainability, is generally referred as agroforestry. In fragile ecosystems of hot arid regions of India

India is a huge importer of crude oil and spends about Rs. 1,200 billion of foreign exchange every year to meet 75% of its oil needs (Anand, 2006). This has affected its balance of payment adversely, especially after the unprecedented rise incrude oil prices. Being an agricultural country endowed with varied climates, nutrient-rich soil and ability to grow many different crops, India offers a great promise as a producer of surplus raw material for biodiesel and bioethanol production. India’s biofuel production currently accounts for only 1 percent of global production (Shinoj et al., 2012). Although all oils can be used, edible oils as a source for biodiesel production have to be ruled out because they are required for cooking and food purposes. Therefore, non-edible oils are the premier raw material for biodiesel production in India. Seeds rich in these oils are mostly produced by perennial species. Hence these trees are referred to as tree-borne oilseed species (TBOS) and they produce TBOs (Aurora and Kumar, 2015). TBOs are cultivated/grown in the country under different agro-climatic conditions in a scattered form in forest and non-forest areas as well as in waste land/deserts/hilly areas. The country has enormous potential of oilseeds of tree origin like mahua (Madhuca indica),neem (Azadirachta indica), simarouba (Simarouba glauca), karanja (Pongamia pinnata), ratanjyot (Jatropha curcas), jojoba (Simmondsia chinesis), cheura (Diploknema butyracea), kokum (Garcinia indica),wild apricot (Prunus armeniaca), wild walnut (Aleurites molucana), kusum (Schleichera oleosa), tung (Vernicia fordii), etc. The best characteristic is that it can be grown and established in the wasteland and have varied agro-climatic conditions. (Aurora and Kumar, 2015)

Distribution

Several countries grow henna on a commercial scale for its dye-bearing leaves, notably India, Egypt, Iran, Niger, Sudan and Pakistan. In India, it was once grown extensively in Punjab and Gujarat. However, gradually the major cultivation has shifted to the arid fringes of Rajasthan, with Pali district having the maximum area under henna. It is taken as an annual Ratoon crop under rainfed conditions. Presently over 39,000 ha of henna plantations in the district with nearly 70 per cent occurring in the Sojat area produce around 20,000 t dry leaves worth Rs. 40 crores. Besides this, leaf cuttings are also collected from existing farms and field boundary plantations in Gujarat and Madhya Pradesh. In Uttar Pradesh henna is grown for its scented flowers used in the essence industry. Kannauj, Lucknow, and Varanasi in Uttar Pradesh are reputed centres for the commercial extraction of mehndi oil from flowers and its use in traditional essence. Since henna is grown as a dryland crop under limited moisture conditions greater use of available moisture by the plants is possible.

Henna or Mehandi (Lawsonia inermis L.) a perennial shrub belongs to family Lythraceae. It is commonly cultivated as a commercial dye crop possess natural dyeing properties and are used for hair dyeing and for staining of palm, feet and other body parts since times immemorial. The plant finds their importance due to presence of orange red dye in its leaves and essential oil in its flower. Oil extracted from leaves and flower called ‘Otto of henna’ which is utilized as perfume (Jaimini et al., 2005). It can grow well in harsh climate of arid and semiarid regions. In India, over 90 percent of the henna production comes from Sojat region of Pali district of Rajasthan and Sojat is only center for its processing and trading in India. In India it occupies about 40,000 ha area out of which 35,000 ha alone is in Pali district (Sojat and adjoining tehsils).

Geographical distribution

It occurs naturally in North Africa mainly in countries of Algeria, Cyprus, Egypt, Eritrea, Ethiopia, Indonesia, Iraq, Iran, Jordan, Kenya, Kuwait, Lebanon, Libya, Malaysia, Morocco, Oman, Philippines, Qatar, Saudi Arabia, Syrian Arab Republic, Tanzania, Tunisia, Turkey, Sahara and Yemen. It is naturally occurring in many of these countries along the water courses and semi-arid regions where it can with stand dryness as well as drought. It has been introduced into countries like Australia, Benin, Burkina Faso, Cameroon, Central Africa, Chad, Congo, China, Gabon, Gambia, Ghana, Guinea, India, Liberia, Mali, Mauritania, Niger, Nigeria, Pakistan, Senegal, Sierra Leone, Spain, Sudan, Togo and Zanzibar (Suresh Kumar et al., 2005).

The arid zone eco-system of Rajasthan is very fragile and is prone to serious imbalance even with the slightest disturbance due to mismanagement of resources. Among the eastern margin of the mean annual rainfall is 500 mm, while in the western most part it is 100 mm. The rainfall is monsoon driven. It comes between June and September (in 9-21 short spells). Large coefficient of variation (40-60%) and erratic distribution during the monsoon are characteristics features of the rainfall, leading often to prolong drought and failure of rainfed crops (More and Samadia, 2007). Temperature as low as 4.4° C, and as high as 50° C has been recorded in Western Rajasthan. Farming system and cropping system approach for sustainable use of farm resources and reduced risks have been successfully demonstrated in perennial horticulture. There is great pressure of livestock on available feed and fodder, as land available for fodder production has been decreasing. The requirement of dry and green fodder by 2025 would be 1170 mt and 650 mt while supply is expected around 411.3 mt and 488 mt deficit will be 64.87 % green fodder and 24.92 % dry fodder (Table 1).

Since time immemorial India has been leader in respect to spice, area, production and consumption. India is known as ‘Land of spices. Out of 109 spices listed by the ISO, India produce as many as 63 owing to its varied agroclimatic regions. Almost all the state and union territory of the country grow one or the other spices. Spices are the sources of livelihood and employment for large number of people in the country. Seed spices are annual herbs, whose dried seeds or fruit are used as spices. Spices are the nature’s gift to mankind and since antiquity, spices have been considered indispensable in the culinary art, as they are used to flavour foods and beverages The important seed spices are coriander, cumin, fennel, fenugreek. ajwain, dill,, celery, anise, nigella and caraway. The other seed spices s are poppy seed, rai, yellow mustard, white mustard, parsley and sesame. In India, Rajasthan and Gujarat has emerged as “Seed spice bowl” and together contributes more than 80 percent of total seed spices.

Burgeoning population exerts pressure on limited precious natural resources for enhancing production of food, fodder and fuel. In order to meet out increasing demand for food, fruit, vegetables, oilseeds, fodder and timber wood for burgeoning population, it is necessary to utilize each unit of natural rsesource very efficiently. The productivity of the precious natural resources is to be enhanced per unit time per unit area by agronomic ally managing stresses soil and land ecosystem to harvest more benefit. The cropping system as well as intercropping system practised by using different trees, fruits, vegetables, crops are the very efficient enterprises for realising higher productivity of natural resources available with in specified ecosystem.

The arid zone of India covers about 12% of the country’s geographical area and occupies over 31.7 mha of hot desert and about 7 m ha under cold desert. The arid regions of Rajasthan, Gujarat, Punjab and Haryana together constitute the Great Indian Desert known as Thar Desert that accounts for 89.6% of hot arid regions of India. In Gujarat, 6.22 m ha area is under arid zone which constitute 19.6% of the arid area of country (Fig 1). In Gujarat, eight districts fall under arid zone, namely, Kachchh (100% of district area), Jamnagar (80%), Surendranagar (29%), Junagadh (20%), Banaskantha (18%), Mehsana (7%), Ahmedabad (6%) and Rajkot 6%).

India has witnessed tremendous increase in the production of horticultural crops especially fruits since independence. Due to specialized scientific interventions and application of latest research tools, the country is now among the top fruit producing countries of the world ranking second next only to China. However, the productivity has still remained low as against area under the fruit cultivation. Several neglecting issues related to the production technology have remained unattended so far. The old and senile orchards are now reverting towards a declining trend of production because of plant age factor, non-compatible varieties and poor canopy management (Baba et al., 2011).

In the recent past declining productivity of old and dense orchards existing in abundance has become a matter of serious concern for the orchardists, traders as well as scientists. In India 30-35 per cent area under fruit crops is occupied by old, dense and diseased orchards. For overcoming the problem of unproductive and uneconomic orchards existing in abundance, large scale uprooting and replacement with new plantations (rehabilitation) will be a long term and expensive strategy. Therefore research efforts were initiated to standardize a technology for restoring the production potential of existing plantations by a technique called Rejuvenation. The term ‘Rejuvenation’ means renewal or making new or young again. As applied to the orchard tree it would mean restoring the productive capacity of the fruit trees. The meaning of ‘Rejuvenation’ according to Chamber’s dictionary is ‘to recover youth character or to grow again’. Obviously, this would apply to those plants which have attained a stage where they are no more profitable from the grower’s point of view.

With the culmination of green revolution, the yield in agriculture is almost static with the use of even great deal of inputs and resources with appearing decadence in nature. The agriculture, if continuous on with same trend, will no longer productive and sustainable. Heterogenity being vested with best survival and sustenance, attempt is underway towards crop diversification deploying remunerative crops and techniques so as to keep pace with rising demand of mankind. Added to this, dwindling land : man ratio (0.13 ha during 1990s), harvesting more return from a unit area of land, disguised unemployment, improper availability of fruits and vegetables (40 g and 120 g respectively as against 120 g and 280 g for fruits and vegetables, respectively), generating employment (143 man-days/ha in cereals, 860 man-days/ha in fruit production and 1000-2500 man-days/ha in cultural intensive fruit crops), are major concerns for high density planting (HDP). It is a holistic production system which helps in promoting and preserving dynamic agro-ecosystem. HDP is also an aid to biodiversity, biological cycles and organic farming. As an alternative to raise production and productivity especially to compete global trade, HDP is worth adoption.

India is a natural reservoir of the several fruit species. The several less known fruit species, which have the potential for commercial exploitation, are yet to be utilized to their potential. An attention to the less known fruit would play a significant role in increasing the income, providing employment opportunities, uplifting of the poor, small and marginal farmers and the development of value added products. These fruits are well known for their medicinal and nutritive value. There is a great need to develop and popularize not only for their domestic market but also for their export. Some of the less known fruits are described here with respect to their cultivation technology.

Vegetables are short duration crops and provide more returns per unit area and time besides, they play a major role in balancing human diet, thus, helping in alleviating hunger and malnutrition (Annon., 2009). In the previous few years, India has attained quantum jump in vegetable production and present estimated vegetable production is around 162.9 mt in an area of about 9.4 mha (NHB, 2014), and holds second position at global level. But this level of vegetable production is insufficient to meet the recommended daily intake (~300 g per capita per day) for a huge population of the country. This is mainly due to lower average productivity (17.5 t/ha) of the nation. There are several crop diminishing factors such as soil borne- and foliar- diseases, insect-pests and nematodes as biotic factors, and soil or water salinity, alkalinity, metal toxicity and heat and moisture stress as abiotic factors, which greatly affect vegetable crops yield in almost all growing areas, especially in fragile arid and semi arid regions.

Vegetables are of short duration, have higher productivity and give more return per unit area, besides giving nutritious food to human being and can be fitted in different farming systems. They also play a major role in balancing human diet, thereby helping in alleviating hunger, poverty and malnutrition. Because of the public awareness for the significance of vegetable consumption, the demand of vegetables in the global market has increased immensely. Thus, vegetable farming is becoming profitable venture globally, opening avenues of self employment and revenue generation (Anon., 2009). At global level, India holds second position, next only to China in vegetables production with a share of about 14%. The present annual vegetables production of country is about 175 million tons from an area about 10.3 million ha with a productivity of 17.1 t/ha. India grows largest number of vegetables in the world, as having a spectrum of wide range of agro-climatic situations, ranging from dry temperate to humid tropics between the altitudes from sea level to snow line.

The Indian hot arid region is one of the most important arid ecosystems of the world in terms of biodiversity it possesses. This arid region spreads over 31.7 mha, occupies major part of north western India including Rajasthan, Gujarat, Punjab and Haryana, which together contribute 73% of arid region. High temperature, wind velocity, low humidity, low and erratic rainfall and high potential evapotranspiration are important characteristics of this region which narrowed down the choice for vegetables, besides permit their low productivity.

Rajasthan has geographical area of 3.42 lakh sq. km has attained the status of being the largest state of India. The state represents 10.4% land surface area with 5.5% population of India, 66% is dependent on agricultural for their livelihood. The state is divided into 33, districts, which are further subdivided into 338 Tehsils and 295 Panchayat Samitis. The total cultivable area is around 220.00 lakh ha. The average rainfall of the State is 575 mm, out of which about 532 mm precipitation occurs in the rainy season i.e. June to September. The average rainfall of eastern Rajasthan is about 704 mm and that of western Rajasthan is about 310 mm which reflects a vast variation. Rivers in Rajasthan are non-perennial except for Chambal and Mahi rivers. The State is presently divided into 33 administrative districts and has 10 agro-climatic zones. Agriculture in Rajasthan is primarily rain fed covering country’s 13.27 per cent of available land. Groundwater is getting depleted as well as polluted. In general, every third year is a drought year. Despite these, the State has made significant achievements since independence and has attained self-sufficiency in food- grains. Rajasthan is located in the north-western part of the subcontinent. It is bounded on the west and north-west by Pakistan, on the north and north-east by the states of Haryana, Punjab, and Uttar Pradesh, on the east; in the south- east by the states of Uttar Pradesh and Madhya Pradesh, and on the south- west by the state of Gujarat. The Tropic of Cancer passes through its southern tip in the Banswara district. In the west, Rajasthan is relatively dry and infertile: this area includes some of the Thar Desert, also known as the Great Indian Desert. In the south-western part of the state, land is wetter, hilly, and more fertile.

The hot arid regions of India are spread over 32 million hectares in the states of Rajasthan (61%), Gujarat (20%), Punjab (5%), Haryana (4%), Karnataka (3%) and Andhra Pradesh (7%). The arid regions of western Rajasthan experience an annual rain fall between 100-500 mm with a coefficient of variations varying from 40-70 per cent. Low and erratic rainfall coupled with extreme temperature results in complete or partial crop failure, considerably affects the agricultural economy of the region. High wind velocity causes wind erosion and shifting of sand dunes covers the fertile agricultural land and canals (Rao and Singh,1998). The rise in temperature begins from March onward and attains its peak in May as high as 46°C. The transpiration is low during winters but during summer in months (May & June), it reaches up to 16 mm per day. The annual estimated potential evapotranspiration values ranges from 1600 mm in eastern part and 1800 mm in western part of the region.

In the arid regions of Rajasthan, Haryana, Punjab and eastern part of arid Gujarat the soils have developed from alluvial and aeolian parent materials. In context to the type of soils light brown sandy soils with dune dominance is 30.6 per cent and associated others 34 per cent area, light brown soils 1.7 per cent, Grey brown soils 13.6 per cent hard pan in 5.9 per cent and seirozems in 1.7 per cent area (Dhir, 1977). Kolarker et al. (1989) reported that in 12 district of Rajasthan sandy soils dominated in 14.3 million ha. These soils are poor in fertility very low organic carbon (0.03-0.1%), light in texture called desert soils (north western) in the order of aridisols. It has undulated topography with the dominance of sand dunes inter-dunal plains. About 80 per cent area falls under rain fed cropping and moth bean, cluster bean, pearl millet, and sesame are the main crops grown during kharif season after the onset of monsoon. Under the vagaries of monsoon and recurrent drought the rain fed cropping becomes a gamble, which creates severe food and fodder scarcity in the region.

The Indian arid zone is characterized by high temperature and low and variable precipitation which limit the scope for high crops productivity. However, these conditions greatly favour the development of high quality in a number of fruits such as date palm, ber, aonla, bael, pomegranate, kinnow, lasoda and in vegetables cucurbits, legumes and solanaceous crops, spices, medicinal and aromatic plants. The existing low productivity could be increased by following improved technologies and inputs. It is now realized that there is a limited scope for quantum jump in fruit and vegetable production in the traditional production areas. The amelioration of the extreme conditions is also considered vital for life support to the inhabitants of this area. The recent awareness regarding the potential of these ecologically fragile lands for production of quality produce has not only opened up scope for providing sustainability for the people of this region, but also for bringing in new areas to increase horticultural production. The area expansion and yield potential of arid horticultural crops has increased many folds because of development of new varieties and advancement in production techniques in arid region.

7.1 Economics and Valuation of ghgs emissions

Since the late 20^th century, it has been largely accepted that cause of high concentration of GHGs in atmosphere is induced by human activities. Greenhouse gas emissions and related climate change has opened up debate on overall economic losses and ways to reduce these loses. Moreover, apart from curbing monetary losses; the global political leaders as well as reputed economists are looking towards making money by saving the emissions. Recently, the researchers have started to emphasize on the actual value added to the ecosystem by curbing emissions, discrete of the economic benefits. This section will discuss the economics and ecosystem services related to the management of GHG emissions.

Origin

The initiative to curb the emissions started in 1992 with the United Nations Framework Convention on Climate Change (UNFCCC) at the Earth Summit in Rio de Janeiro. The Convention took place from 3 to 14 June, 1992. The UNFCCC is an international environmental treaty designed to “stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system”. The UNFCCC had non-binding limits on greenhouse gas emissions for individual countries and the framework was only meant for formulating precise international treaties (called “Protocols” or “Agreements”). It contained no execution mechanisms, however, it considered some negotiations and suggestions to formulate the action plans and regulation guidelines under UNFCCC to fulfill the objective of reduction of GHG emissions to the desired level.

What is mitigation of GHGs emission? We must be clear about the answer of this fundamental question. In simple term, the mitigation of GHGs emission is the way or means by which the emission of those gases could be reduced. As we know from the previous chapters of this book that the GHGs emission could be occurred from natural as well as anthropogenic activities. Natural activities included volcanic eruptions, ocean current fluctuations, continental drifts which are responsible for emission of huge amount of CO₂ and other GHGs. The reduction of emissions from those natural activities is beyond our capabilities. However, the human induced emissions of GHGs emission could be reduced. We studied in previous chapters that fossil fuel burning, industrial and energy sector pollution, deforestation, land use change and agricultural could contribute to GHGs emission considerably. Mitigation techniques are different for each of those sectors that governed by lot of interrelated factors. In actual sense, the mitigation of GHGs emission should includes all the measures that can curtail the anthropogenic emission from all sectors. But that is out of the scope of this book. In this book, we specifically address the mitigation principles, options and efficiency of different techniques/ practices in agriculture only.

In that aspect, the mitigation of greenhouse gases emissions in agriculture is defined as “the means and ways by which emissions of GHGs could be reduced from agriculture”. The ways and means actually referred to the techniques and practices and their amalgamation in agricultural sector both in production, processing and consumption aspects. So, mitigation is not only a techniques or combination of techniques it is actually an integrated approach for reducing greenhouse gases emission from agricultural systems. Primarily, there are two complementary approaches for mitigation of GHGs emissions from agriculture. Those two approaches are (i) supply-side and (ii) demand- side options or pathways. The supply-side approaches includes scientific land- use-changes, improvement of crop management, better livestock management practices, enhancing carbon storage in biota, soil carbon sequestration, significant substitution of fossil fuel by bio-fuels and use of renewable energy in agriculture. On the other hand, demand side approaches, taken in to account of shifting in the dietary pattern from non-vegetarian to vegetarian, curtail down the food loss and waste, and reducing the supply-chains (Figure 6.1). We can see, most of the approaches in supply-side are technology driven, while, approaches in demand-side are socio-economical and or policy driven. In this chapter we would thoroughly discuss the principles of mitigation, options of mitigation, mitigation cum adaptation approaches to reduce GHGs emission and climate change and few strategies to cope up with the vagaries of climate change.

5.1 Impact of climate change on agriculture

Climate change has both positive and negatively impact on agriculture, food security and land degradation. Climate change could exacerbate the land degradation processes by increases in rainfall intensity, drought frequency and severity, dry spells, f looding, heat stress, sea-level rise and permafrost thaw. The 1/4^th of ice-free land area in the world is prone to human-induced anthropogenic degradation (Certini and Scalenghe, 2011; Hooke et al., 2012). Soil erosion rate is 20-100 times faster than that of soil formation in agricultural field. The erosion rate is least is zero-tillage (non-disturbed field) and maximum at conventional intensive tillage practices. Climate change further exacerbates the land degradation. The permafrost areas, dry-lands, low-lying coastal regions, river deltas are more vulnerable. The occurrence of drought in dry-land was increased by around 1% per year during 1961-2013 periods. On an average 380-620 million people globally experienced desertification who lived in dry-land areas (1980s and 2000s) in South and East Asia, North Africa, Middle East, Sahara region, and Arabian peninsula. Moreover, people who are already living in degraded/ desertified regions are more negatively affected by climate change.

Specifically, the land surface air temperature has increased about twice as much as the global average temperature since the pre-industrial era. The land-surface air temperature has increased relatively higher than the world’s average surface (land and ocean) temperature since the pre-industrial era (1850-1900). The average land-surface air temperature has enhanced by 1.53°C (1.38-1.68°C), whereas, world’s surface (including land and ocean) air temperature has enhanced by 0.87°C (0.75-0.99°C). Subsequently, global warming triggered the frequency, intensity and duration of heat waves and related damage. The direct and indirect impacts of climate change on global agriculture is summarised below for an overall idea about the importance of the issues.

The measurement of greenhouse gases (GHGs) has been started during middle of the last century. Initially, CO₂ and water vapour were measured with other common meteorological variables like temperature, sunshine hours, rainfall, humidity etc., for monitoring the weather condition and pollution. The absolute or relative concentrations of gasses in atmosphere are used to measure basically for monitoring purpose. However, limited studies were dealt with actual gaseous exchanges of fluxes. The concern about gaseous flux measurement and GHGs-exchanges started after 1900s when people got concerned about anthropogenic pollution, environmental sustainability and climate change issues. The GHGs-exchanges in earth-atmosphere systems primarily occur due to change in meteorological variables, soil responses and physiological activities of crops. If we are interested for environmental data inventories, then absolute GHGs concentrations of atmosphere at a specific time is required. However, presently researchers, students, environmentalists, climate scientists are primarily interested for quantitative data on GHGs fluxes and or GHGs-exchanges. They want to know what and how much quantity of a particular GHG is emitting from unit area at unit time.

Flux refers to the amount of any gas emitted per unit area per unit time. The dimension of that is M A^-11 T^-1. (Where, M= Mass/ Quantity; A= Area; T= Time). The SI unit of flux is g m²s^-1. Therefore, flux is a vector. It has magnitude as well as direction. As for example positive flux of CO₂ from earth surface means, CO₂ is moving out from earth surface to atmosphere. If it moves in opposite direction then the flux would be negative. In that case CO₂ gas may be absorbed by the soil surface from adjacent atmosphere. Similarly, GHGs fluxes of earth surface are either positive or negative. Generally, positive GHGs flux refers to emission of GHGs from earth to atmosphere and vice versa.