eChapters

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

Introduction

Production system under arid and semi-arid region faces several biophysical constraints (high solar radiation, low and erratic rainfall, high wind velocity, poor soil conditions, etc.). Availability of irrigation water and irrigation potential in these regions are meager. Nutrition, food security and sufficient livelihood options based on agriculture are the major challenges of the people living in these regions. Sustainable productivity in these regions cannot be achieved by monoculture of either seasonal or forage crops, and thus hinges the need for diversifying the cropping pattern through fruit based cropping system which has good potential particularly in the arid and semi-arid regions. Because hunger and malnutrition are often linked to poverty, providing economic opportunities through horticultural production not only helps family incomes, but also addresses food security and nutrition. Thus, cropping system approach for agricultural production has greater significance in these regions.

Introduction

The green revolution technologies involving the greater use of synthetic agrochemicals with adoption of nutrient responsive, high yielding varieties of crops have boosted the production output. However, this increase in production has slowed down and in some cases there are indications of decline in growth of productivity and production. Environmental and health problems associated with agriculture. These questions have given rise to a process of serious thinking to safeguard the environment and the quality produce.

Introduction

India is the second most populous country in the world. The per capita cultivable land resource is shrinking day by day. To meet the food, fibre, fuel, fodder, and other needs of the growing population, the productivity of agricultural land has necessarily to be increased. It requires increased use of agricultural inputs like quality seeds, fertilizers, water, agro-chemicals, etc. in such a manner that do not create any environmental problems.

Plant needs different chemical elements to grow and thrive. The most important chemical elements include (i) carbon, hydrogen and oxygen, which are basic life building blocks and are available in plenty from air and water (ii) nitrogen, phosphorus and potassium which are the macro nutrients and affect the plant growth significantly (iii) sulfur, calcium, and magnesium as secondary nutrients and (iv) boron, chloride, copper, iron, manganese, molybdenum and zinc as micronutrients in very small quantities.

What is Precision Farming?

It is information and technology based farm management system to identify, analyze and manage variability within fields for optimum profitability, sustainability and protection of the land resource without disturbing the environment. It is basically means adding the right amount of treatment at the right time and right location within a field.

Introduction

Plant hormones (also known as phytohormones) are chemicals that regulate plant growth, which are termed ‘plant growth substances’. Plant hormones are signal molecules produced within the plant and occur in extremely low concentrations. Plant hormones are small, simple molecules of diverse chemical composition: indole compounds, terpenes, adenine derivatives, steroids, aliphatic hydrocarbons and derivatives of carotenoids or fatty acids. In the context of rooted habit and iterative mode of growth, plant hormones are not produced in specialized glands, but in most parts of the plants. Plant hormones are required in minicule quantities and their concentrations at sites of activity are precisely regulated. Changes in hormones concentration and tissue sensitivity mediate a whole range of development processes in plants, many of which involve interaction with environmental factors. First five hormones discovered from the plants were gibberellins, abscisic acid, cytokinins, indole-3-acetiv acid, and ethylene as well as some compound shown more recently to have a regulatory role in plant development, namely, brassinosteroids, polyamines, jasmonic acid and salicylic acid.

Introduction

Plant needs nutrients for their growth and development. In a systemic agriculture, nutrients are supplied to the plant in different amount, form and time for the economic and optimum crop production. Green revolution realized in the late sixties of the last century is an outcome of efficient use of improved varieties and nutrient management. Success of the green revolution has increased use of chemical fertilizers in the post green revolution era. Soon the chemical fertilizers become indispensible from all the crops including vegetable and plantation crops. Non judicious use of chemicals in the agriculture has lead to the serious health, soil and environmental hazards. Biofertilizers are considered to be the most safe, promising and economic component of sustainable agriculture. Biofertilizer is a substance which contains living or latent microorganisms which, when applied to seed, plant root or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by providing and essential nutrients or increasing the supply or availability of primary nutrients to the host plant. They can applied in all the agronomic, horticultural and plantation crops.

Mineral Nutrition and Nutritional Deficiency

The normal green plant is autotrophic that means it can synthesise all its organic substances; provided it is supplied with all the inorganic elements and growth under normal condition. The nutrition of green plant is therefore, solely inorganic. It is, in fact, commonly called mineral nutrition. Element absorbed from the soil by the roots are generally known as Plant nutrition or Mineral nutrients.

Introduction

The horticulture sector has been a driving force in stimulating a healthy growth trend in Indian agriculture. This sector contributes around 28 per cent of the GDP from about 13.08 per cent of the area and 37 percent of the total exports of the agricultural commodities (Rather et al., 2013)  India is currently producing 257.2 million tonnes of horticulture produce from an area of 23 million ha. Over the last decade, the area under horticulture grew by about 3.8% per annum but production rose by 7.6% per annum. The higher growth rate in horticulture was brought about by improvement in productivity of horticulture crops, which increased by about 28% between 2001-02 and 2011-12. (Anonymous, 2012)

Introduction

Green house is a structure in which external climatic factors can be controlled for cultivation and protection of crops. It has mainly two parts. (a)  a frame or the basic structure and (b) the cladding or covering material (U.V. film) Frame can be made of G.I. pipes, bamboos, woods or iron rods while the cover can be of glass or plastic films. In India the technology is primarily used. Greenhouse technology is more suited to vegetables crops (such as tomato, cauliflower, capsicum, cucumber, leafy vegetables etc.), and flowers (like rose, gerbera, carnation, etc).  This technology is mainly suitable for commercial farming, as it requires investment in setting up the entire framework.  Based on cooling systems of the greenhouse, it can be classified as naturally ventilated and fan-pad type greenhouse.

Introduction

In horticulture crops, plant materials has been  propagated through vegetative propagation methods for its superiority in growth as well as yield for centuries. Among vegetative propagation methods, micropropagation is most advance technique which made a significance in the horticultural crops to increase quality and yield. It can produce many plants from a single individual.

Current Trends in Fruit Exports from India

Fruit culture in the Indian subcontinent dates back to the Harappan civilization when datepalm, pomegranate and lemon were domesticated. Fruits such as aonla, bael, jackfruit, karonda, phalsa, mango, pomegranate, almond, walnut and pistachio are mentioned in Charaka Samhita (300 BC) and Sushruta Samhita (400 BC), the oldest known texts on ayurveda. Owing to diverse agro climatic conditions, India can produce a wide range of tropical, subtropical, arid and temperate fruits. In the past few decades, India had made rapid strides in fruit production and is currently the second largest producer of fruits in the world, next only to China. The annual production is estimated to be about 81 million tonnes for about 12.6% of the total world production. However, India’s share in the global export of fresh fruits is less than 5 per cent. The major fruits exported in terms of quantity are grape, mango, banana and pomegranate. In value terms, grapes and mango earn the maximum foreign exchange for India.

Introduction

Agriculture is highly dependent on environment, and it’s very difficult to get favourable climate and other conditions for optimum crop growth and development as per crop need. Open field conditions are having a high direct affect of the prevailing weather conditions on crop growth, and also on population dynamics of viruses, fungus, bacteria, insects, etc. With time crops has adopted themselves to specific seasons, but the fast changing climatic conditions happening across the globe has changed the climatic characteristics of a season. This has resulted in untimely rains, high temperature fluctuations and changes in other abiotic and biotic factors in geographically varied locations where it was not supposed to be earlier based on various geographical factors deciding the climatic conditions of that area. Therefore, there is need to develop suitable technologies to sustain these challenges. How to address these issues, can we manipulate the climatic conditions or can we provide protection to the crops against climatic fluctuations and various other related stresses.

Introduction

Citrus spp. grown in almost all the states of India. Citrus fruit, consisting of mandarin oranges (Citrus reticulata Blanco), sweet orange (Citrus sinensis Osbeck) and lime (Citrus aurantifolia Swingle) are grown commercially in tropical, sub-tropical, arid, irrigated and mountainous regions in varying soil and weather condition. The citrus tree on the whole do well in dry climate, with a rainfall between 75 and 125 cm but certain species such as pummel and certain mandarin oranges thrive in heavy rainfall areas of Konkan, Assam and Coorg. It is grown almost all kinds of soil, varying from heavy black soil to shallow open soils. A hard substratum or a sticky impervious layer is very injurious. Soils having a high water table should be avoided. Although the citrus industry in India has faced many challenges, there has been a consistent increase in area and production owing to the awareness for sustained production (Table 1).

Introduction

Vegetable crops are an important component of Indian Agriculture. They are known for their short cycle and high productivity per unit area providing a valuable source of income leading to improve livelihood. The prosperity and advancement of a nation largely depend on achieving nutritional security to its people. The vegetables play a vital role as major supplement to food and nutritional security of our people. They are important source of nutrients like b- carotene, vitamin B, C, E as well as folic acid, iron, magnesium, etc. and they also supply fair amounts of carbohydrate, protein, fiber, antioxidants and energy.

Introduction

India (8^o-30^o N and 68-97.5^ºE) exhibits a wide range in topography and climate, which has a bearing on its vegetation and floristic composition. This subcontinent is one of the World’s 12 leading Biodiversity Centres, encompassing 16 different agro-climatic zones, 10 vegetation zones, 25 biotic provinces and about 426 habitats of specific species. It has been estimated that about 45,000 plant species (nearly 20% of the global species) occurs in the Indian Sub-continent. About 3,500 species of both higher and lower plant groups are of medicinal values. More than 80 per cent of medicinal and aromatic plants (MAPs) are collected from 17 million hectares of Indian forest land. However, many of these, due to over-exploitation have become rare (Rheum emodi, Aconitum deinorrhizum), threatened (Rauvolfia serpentina, Berberis artistata) or endangered ones (Sassurea lappa, Dioscorea deltoidea). Problems arising out of rapid genetic loss of medicinal plants forced the need for international co-operation and co-ordination to undertake programmes for conservation of medicinal plants to ensure that adequate quantities are available for future generations.

Introduction

Beauty, purity, love and passion are some of the emotions symbolized by the flowers. The feelings of love, affection and joy are conveyed effectively with these non-speaking beauties of nature, for example a lotus conveys purity, rose love, pansy thoughts and narcissus egotism. Flowers have a definite role to play at almost all occasions of human affairs like birth, marriage, worship, adornments and death. Besides flowers, other ornamental plants also play an important role in environmental planning of urban and rural areas and from wasteland development to overcoming pollution. An important aspect of floriculture is that it is a good avenue to generate gainful employment for youth and women of peri-urban and rural areas.

Introduction

Vegetables are the vital sources of minerals, vitamins and dietary fibres and play an important role in supplying nutrition to human health. Vegetables require comparatively lesser quantities of agro-inputs to grow. Vegetables are rich source of vitamins, minerals and plant fibres which provide food and nutritional security. These also generate high income and employment, particularly for small farmers. Vegetables being a rich and cheap source of vitamins and minerals, occupy an important place in the food basket of Indian consumers, a majority of whom are vegetarian. This persistent vegetarianism coupled with rising per capita income is fuelling a rapid growth in consumption of vegetables. Presently, India is producing more then 70 types of vegetables which are capable of meet out the economic and nutritional requirement of the country (Table 1). There has been a revolution in the production of vegetables in the country in the last four decades.

Introduction

Horticulture is the science of cultivation, management, postharvest handling, value addition and marketing of fruits, vegetables, ornamental, aromatic and medicinal plants, spices and plantation crops. Looking to its important role in nutritional security, poverty alleviation and employment generation, it has rightly been emerged in form of horticulture industry and as one of the most significant sectors in the world. The production of fruits, vegetables and flowers has acquired much importance in recent times due to their increasing demand. Changing lifestyles of people across the globe, attempts to overcome the stressful lifestyle, inclination towards healthy and balanced eating habits have made people include fruits and vegetables in their daily diet. In the case of flowers, the demand for fresh flowers has steadily increased not only for decoration but also for many other purposes like essential oils, cosmetics, aroma therapy, dry flowers, pot-pourries, natural dyes, medicines, etc. Rising incomes and growing consumer interest in a variety of fresh fruits and vegetables year-round is stimulating international trade in horticulture.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Some of the constraints in cashew production in the country which limits the productivity of cashew per unit area

• % Large area under cashew in the country is still covered with non-descript genetically inferior seedling progenies.

• % Cashew is a neglected plantation crop among the farmers and generally grown under neglected condition.

• % The land which is not suitable for other plantation crops only are available to cashew crop. Hence, the land which is available for cashew is usually eroded and degraded with poor soil fertility.

• % Farmers are not fully aware of the latest cashew production technologies due to inadequate transfer of technology.

• % Even if farmers are aware of the latest cashew production technologies, non adoption of recommended package of practices to the extent required.

• % Absence of compact and dwarf high yielding varieties, because of which high density planting cannot be adopted to realize the full potentiality of high density planting technology.

Cashew is one major crop of Konkan region of Maharashtra and requires comparatively less expenditure for cultivation as compared with other crops. Under normal planting density (7m x 7m), about 200 plants/ha are occupied. If the cashew grower has its own land, then for first five year of orchard establishment and maintenance, total expenditure of Rs. 47447 is come up. Year wise expenditure (first five years) on cashew cultivation per hectare is presented in Table 61.

Cashew (Anacardium occidentale L.) is one of the most important commercial crops of India. The crop is grown on commercial scale in coastal Maharashtra and other states of the country. The main reason for the low productivity is the pest incidence. The insect pests cause crop loss ranging from 30 to 40 per cent in cashew (Satapathy, 1993). Keeping in view, the strategy of increasing production, one of the important aspects is to develop technologies to save the crop from the pest incidences.

Cashew is attacked by around 180 species of insect and non-insect pests in India resulting in substantial yield loss (Sundararaju, 1993b). Godse et al. (2004) reported over 58 species of insects and pests on cashew crop in the Kokan region of Maharashtra region. The infestations of insect pests have been identified as one of the major factor responsible for low productivity. The most important pests that limit production are the cashew stem and borer (CSRB) and the tea mosquito bug (TMB). In addition, leaf and blossom webber, shoot tip caterpillar, and apple and nut borer cause damage. Recently, apple and nut borer and leaf miner are emerging as major pests and they also occasionally becoming serious in some orchards.

Cashew apple, a highly potential nutritional source, is almost entirely wasted now. In Goa, cashew apple juice is fermented and distilled for production of alcohol. Cashew apple is juicy and swollen. It is a rich reserve of vitamins and minerals. The cashew apple is the peduncle of the nut. Normally the apple is 8 to 10 fold large by weight compared to cashew nut, at ripe stage. Cashew apples can be of different size and shape. The ripe apple is very juicy and fibrous with thin skin. When fully ripe, it gets detached from the pedicel and falls down. In Brazil, cashew is a popular fresh fruit and dwarf types are being evaluated to fulfil the market requirements of fresh cashew apple in terms of red colour, high sugar, low tannin etc.

Brief History of Cashew Nut Processing Industry in India

As is known in the Cashew Trade Circles, cashewnut was not an indigenous product of India. A few hundred years back, the Portuguese brought it to Goa in India, from Brazil. The Portuguese also took it to their other colonies in Africa viz. Mozambique on the East Coast and Angola on the West Coast. In Mozambique, it spread all over the territory i.e. from Lourenco in the South to Ibo in the North and thence to British East Africa (now Tanzania) and Kenya. Though, now it is known as cashewnut, still in Mozambique and India, it is known by its original Portuguese name ‘CAJU’.

Cashew Kernels

The role of balanced diet in contributing to a long and healthy life is undisputed. Diet related diseases are quite common even among the people of the affluent West. Unlike in developing countries, where many diseases are caused by deficiency in the quantity and / quality of diet. The diet related diseases among affluent populations result from excessive consumption of undesirable foods. Over consumption of foods of animal origin like meat and eggs are implicated in the causation of atherosclerotic heart diseases. Annual food consumption has also been suggested as possible aetiological factor in some cancers. After years of research, scientists are finding health benefits in a largely plant based diet emphasising foods low in saturated fats. On the basis of the awareness that excess animal food consumption is harmful, recent dietary guidelines all over the world recommend a reduction in the intake of meat and meat products and a liberal increase in consumption of fruits and nuts. Like meat and eggs, nuts are abundant in proteins, the body building material essential for growth and maintenance of tissues. Nuts are also a concentrated source of energy, since they contain liberal amounts of fat.

Raw cashew nuts are a seasonal commodity and the trading season is from March to May. Growers usually supply the primary or village markets where small traders collect and supply the urban markets. The cashew trade is seldom handled by exclusive traders. Usually, those traders who collect other plantation products also trade in cashew. Due to the highly competitive nature of the cashew trade, growers have few marketing problems. When large quantities are collected by middlemen, the processors enter the marketing chain and make wholesale purchases. Grades and standards for cashew are yet to be introduced in India. Quality is generally determined by appearance and cutting tests that traders employ prior to purchase. The raw cashew nut market involves a large amount of capital where nearly 80 per cent of the produce is transacted within a period of 35 days. The current value of Indian production is estimated at around Rs. 10,000 million. This capital is made available by industry for procurement and processing operations.

There are no growers’ cooperatives or organizations for cashew marketing. In Kerala, however, the government has been involved in the procurement process and supply to large-scale processors. This adversely affected the cashew trade and has now been replaced by a free market policy.

In addition to the local production of nearly 7 lakh tonnes, India also imports a considerable quantity of raw nuts from several African and South-east Asian countries to satisfy the national processing capacity of about 12-14 lakh tonnes established in the country.

Introduction

Once the cashew fruits fallen, are collected, the nuts are to be separated from the cashew apple and sun dried for 2 to 3 days. This is very important in view of the quality of kernels obtained during subsequent processing. Raw nuts at the time of harvest will have moisture content ranging between 16 to 25 per cent; while sun dried nuts have moisture content of 8 to 10 per cent (Nagaraja, 2000). If the nuts are not dried and stored properly, it leads to fungal spoilage resulting in poor quality of kernels. Fungi such as Gonatobotryum, Helminthosporium sp., Corynespora sp., Alteraaria sp., Verticillium sp. and many species of Aspergillus have been isolated from stored cashew nuts (Joseph, 1981). In view of the occurrence of fungi, drying of the raw nuts before storage becomes absolutely essential. Maximum permissible moisture content of raw cashew nuts is 8.7 to 9.1% (Ohler, 1979). Okwelogu and Mackay (1969) have reported that high whole nut or kernel moisture percentages are closely associated with high shell moisture contents and for nuts whose moisture content is in equilibrium with the ambient relative humidity, the moisture content of whole nut and kernel could be predicted from that of shell with more than 99% accuracy. A higher kernel shell weight ratio has been shown to be inversely proportional to moisture content.

Maturity of Cashewnut

Cashew fruit has two parts namely cashew nut (actual fruit) and cashew apple (pseudo fruit). Development of these is not parallel. Cashew nut develops first and the pseudo fruit develops later. It takes 60 days for both the nut and the pseudo fruit to develop completely since anthesis. Development of cashew apple and nut has been studied by number of workers in different cashew varieties (Rao et al., 1962; Augustin and Unnithan, 1981; Mohan Kumar et. al., 1984; Antarkar and Joshi, 1987). According to the report, specific gravity could be considered as physical index of maturity of nut in cashew varieties of V-1, 2, 3, 4 and 5 (Antarkar and Joshi, 1987; Mohan Kumar et al., 1984). In Thailand, the nut reached maximum size in 4 weeks after fruit set, hardened in the subsequent week and declined in size by 10 per cent at harvest (Sumrit Feungehan et al., 1989). Augustin and Unnithan (1981) have reported that the growth of nut is faster during early stage of development than that of fruit. All these reports indicate that the cashew nut develops earlier than cashew apple. Changes in the composition of cashew nut and apple during development have been looked into by various workers. Hariharan et al. (1985) have reported decrease in amino acid content in kernel with increased maturity. Cashew kernel lipid, free amino acids and CNSL have been shown to increase with increased maturity. Similarly, cashew kernel phenols have been shown to decrease with maturity. Changes in the kernel sugars and starch were not uniform (Anon., 1998).

In the orchard, several cultural operations like weeding, mulching, etc. are very important. Similarly protection from fire is also essential. The points are discussed here.

Weed Management

The Luxuriant weed growth is a common sight in neglected old cashew gardens. Weeds are not only harmful by competing for the nutrients and moisture but also cause inconvenience to take up effective plant protection measures and harvesting of fallen nuts; thus resulting in loss of yield. Therefore, sanitation of cashew orchard is very essential, it also minimise the incidence of cashew stem and root borer (CSRB). Careful weeding-clearing the area within 2 m radius of the trunk is essential. Clearing of weed growth is to be carried out twice in a year. Weeds may compete for nutrients and moisture with cashew. The weeding cycles are generally confined to the pre-monsoon and post-monsoon periods to coincide with the fertilizer application.

Weeds should also be controlled between the rows. This can be done by inter-cropping with certain crops for 3/4 years before the tree canopies close in. In addition a legume can be grown to both control weeds and fix nitrogen for the trees. This improves the soil and makes the nutrient available.

Intercropping

Canopy of cashew to cover the entire area in about 8 to 10 years when grown under normal spacing of 8m x 8m in fertile soil. However, in marginal lands, it takes 10 to 12 years for the canopy to cover entire area. Cashew when grown in hilly regions there is a possibility of soil erosion and weed growth during initial years of planting (Yadukumar and Nayak, 2000). Intercropping is the only available best options to prevent such erosions and conserve soil and moisture in hilly areas and to obtain sustainable income.

Recently, establishment of large plantations and adoption of systematic package of practices and intercropping is practiced to realize additional income in the initial years of cashew cultivations. When the cashew canopy starts touching the neighbouring trees possibility of intercropping is ruled out. Mixed cropping with other tree species is not widely accepted and even not advisable (Anon., 1997), though there are a few instances of growing casuarina as mixed crop in Andhra Pradesh and Orissa states (Yadukumar and Nayak, 2000).

In the field of agriculture/horticulture, various irrigation systems are being employed to fulfil the water requirement for better growth and development of the tree. Since, cashew is hardy plant which can sustain in rainfed conditions of warm and humid region; it has very good potential to produced higher nut yield. Of the various irrigation methods, drip irrigation system is best method in the areas where natural resources of water is limiting factor. It is well known fact that this system has many advantages.

During the first year after planting, protective irrigation is recommended at 15 days interval during winter and at 8 days interval during summer season. At each irrigation, 25 litres of water to be given per graft. The studies on mulching and irrigation were under taken with a view to determine fruit retention. It was observed that black polythene mulch with irrigation @ 60 liter of water per tree at 15 days interval showed beneficial effect on increasing fruit retention (66.15%) over control. Cashew is grown under rainfed conditions. However, supplementary irrigation during summer months, especially during January-March at fortnightly intervals @ 200 litres/plant proved to double the yield. This is evident from the research results obtained at NRC-Cashew, Puttur (Karnataka).

Pruning in young tree during initial stage help to form a strong frame work for better growth and development of the tree. However, on long term way, the tree becomes huge with gigantic canopy results in to problem of majority of agronomic operation, plant protection and harvesting of crop. Top working provides an opportunity to control the growth of tree and makes the tree productive with manageable canopy, in old and senile orchards.

Top working is a technique evolved to rejuvenate the unproductive and senile cashew trees. Poor yielding trees of 5-15 years of age can be successfully rejuvenated by top working. The unproductive trees are to be headed back to a height of 1.00 m from the ground level in October-November. The stem should be sawed off to avoid stump splitting. Soon after beheading, the stumps and cut portions should be given a swabbing with carbaryl 50% WP (50 g each per litre of water) or Bordeaux paste. Sprouts emerge 30-45 days after beheading. Sprouting will be profuse in young trees. So, it is better to keep only 4-6 healthy shoots on beheaded tree spreading in all directions and similarly the sprouts which come out from ground level (most probably water shoots) also removed frequently. On 30-45 day old shoots, graft scions of high yielding varieties following soft wood grafting technique. On each tree, 4-6 grafts are to be done to ensure at least 3-4 successful grafts per tree. The best season for grafting is March-April. Thinning of the extra shoots arising from the stumps should be done to obtain better growth of the grafts. Removal of sprouts below the graft joint and removal of polyethylene strip from the graft joint should be done. Top working is simple and can be done by farmers themselves after getting proper training. The top worked trees start yielding right from the second year of top working. Early bearing can be treated as one of the best advantages of this technique. The major disadvantage associated with top working is the huge casualty of trees due to stem borer attack. Intensive care and management to ward off stem borer is essential. As such adoption of top working on a larger scale would be difficult.

Canopy management is the manipulation of tree canopies to optimize the production of quality fruits. The canopy management, particularly its components like tree training and pruning, affects the quantity of sunlight intercepted by trees, as tree shape determines the presentation of leaf area to incoming radiation. An ideal training strategy centres around the arrangement of plant parts, especially, to develop a better plant architecture that optimizes the utilization of sunlight and promotes productivity. Light is critical to growth and development of trees and their fruits. The green leaves harvest the sunlight to produce carbohydrates and sugars which are transported to the sites where they are needed – buds, flowers and fruits. Better light penetration into the tree canopy improves tree growth, productivity, yield and fruit quality. The density and orientation of planting also impact light penetration in an orchard. Generally, in close planting, quicker shading becomes a problem. An east-west row orientation results in more shading as compared to the western and southern orientation of trees. Strong bearing branches tend to produce larger fruits. The problem of a fruit grower is initially to build up a strong and balanced framework of the trees, then equip them with appropriate fruiting. Obviously, pruning in the early years has to be of a training type to provide strong and stocky framework with well spaced limbs or any other desired shape.

Various studies have demonstrated that the cashew tree responds to the application of mineral nutrients, though the responses are significantly affected by plant age, the genotype utilized, the conditions of cultivation, soil and climate and of the crop management (Barros et al., 1984; Ghosh, 1990; Ximenes, 1995; Bezerra et al., 1999; Crisóstomo et al., 2005). The crop develops well under semi-arid conditions, in which the problems associated with water availability and salt excess in the root environment are common. These two factors interfere with the acquisition of nutrients, in that the levels of nutrients in the plants are affected both by direct effects on absorption and transportation processes and by indirect effects associated with a reduction of growth of the various plant organs including the root system. The effect of salinity on plant nutrition depends on the types of salts that predominate in the cultivation environment which can result in a deficiency of essential nutrients and an excess of toxic ions. These changes under salt stress are accompanied by a loss of structural and functional integrity of the cellular membranes, a reduction in activity of various vital enzymes, and a diminished capacity of the roots to absorb nutrients (Zhu, 2001). On the other hand, water deficit reduces the extraction of nutrients from the soil, limiting the solubilization of nutrients in the root environment and altering the morphology of the root system (Kramer and Boyer, 1995). It should be added that the effects of excess salt and water deficit depend on various factors, including the species under study and the stage of development at which the plants are submitted to these.

Selection of Site and Land Preparation

Cashew is a hardy plant; it thrives well on wide range of soil. While selecting the land for cashew, soils with water logging and excessive salinity of alkalinity should be avoided. Otherwise, soil depth, slope, stoniness, soil fertility and water availability seem to impose very little limitation. For establishing new plantations, land preparation should begin with the first pre-monsoon rains. The area should be cleared of bushes and other wild growth before digging pits for planting.

Planting Season

Planting of soft wood grafts is usually done at the beginning of monsoon season (June-July). Therefore, land preparation such as clearing of bushes and other wild growth, digging of pits for planting, should be done during pre monsoon season (April-May).

The emasculation and pollination in any crop depend on its floral structure and biology. Cashew is basically andromonoecious (polygamo monoecious) crop with staminate and hermaphrodite flowers appearing in the same inflorescence or panicle (Rao and Hassan 1957). The hermaphrodite/bisexual/perfect and male flowers occur intermediately in the same panicle in three or four phases viz., Male – Mixed – Male or Mixed – Male – Mixed– Male. Distinct phases depend on genotype and environmental factors. The tree shows considerable variation in the duration of different phases. The hermaphrodite flowers are bigger in size than staminate or male flowers (Damodaran et.al., 1965). Male flower always exceed the bisexual flowers. The flowers produced early in a panicle are mostly male (Rao and Hassan 1957; Damodaran et. al., 1965). Most of the perfect flowers are produced about one month after the first flower occurred in the panicle (Bhat et al., 1998).