eChapters

Pattern of Growth Flushes in a Bearing Tree

Two or three peak periods of growth are usually observed in a bearing cashew tree, even though under favourable conditions the stray shoot growth may occur almost every month. The pattern of growth of a bearing tree consists of a generative flower flush (reproductive) and a vegetative flush. The vegetative flush, consisting of lateral shoots, always develops soon after the main crop has matured. Flowering is terminal and is universally preceded by the vegetative flush.

There are two types of branching in cashew, intensive and extensive.

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).

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).

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.

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.

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.

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).

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 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.

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).

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.

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.

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.

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 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.

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 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.

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.

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.

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.

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.

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.

“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.

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.

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.

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.

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.

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.

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.

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.

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:

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.

Agriculture is a branch of Applied science. It is the main enterprise in the world. In a true sense, it is a productive unit where the gift of nature i.e. land, light, air, temperature, water, humidity etc. are integrated into a single primary unit – crop plants and their usable parts are thus indispensable for human beings. Secondary productive units are animals (livestock), birds, insects etc. and they  feed on these primary units and provide more solid products such as meat, milk, wool, eggs, honey, silk, leather etc.
The word agriculture is derived from two Latin words i.e. Ager/Agric means soil and cultura means cultivation. Thus, “Agriculture is a science of cultivation of land”. It is an art and science both in which we study all the activities of human beings related to use of soil. 

What is Crop?
Crop refers to plants sown and harvested by man for economic purposes. 
Cropping Seasons: There are three main seasons and two sub seasons.
1. Rainy or Kharif Season – Main characteristics of the Kharif season are 
    ·    It starts from June and spreads to September.
    ·    There is high temperature and high humidity.
    ·    More than 2/3^rd of annual rainfall is received in a year.
    ·    In the beginning, days are longer than nights while days and nights are equal when season ends. 
    ·    Important crops grown are maize, rice, sorghum, Moong, Urd, groundnut, cowpea, soybean etc. 

Soil  and its Components
Soil
Soil is a three dimensional, transferable natural material which is found on the earth crust and provides natural medium to plant growth. OR
Soil is the upper most loose layer of the earth, suitable for plant growth. 
Different scientists defined ‘SOIL’ in different ways:
Buckman and  Brady defined soil as  “A dynamic natural body on the surface of the earth in which plants grow, composed of mineral and organic materials and living forms”.

The problem soils are those which, due to its land or soil characteristics, cannot be economically used for the cultivation of crops without adopting proper reclamation measures. 
Classification of  Problem Soils:  The problem soils are divided into 3 groups. 
    ·    Highly Eroded Soils 
    ·    Saline and Alkali Soils 
    ·    Acid Soils 
Highly Eroded Soils
These soils are called ‘Usar’ in U.P., ‘Kallar or Thur’ in Punjab and ‘Luni’ in Rajasthan. In India, area under saline alkali soils is 7.0 mha. When the chloride (Cl), sulphate (SO₄^2-), carbonate (CO^₃2-) and bicarbonate(HCO₃-) salts of sodium (Na⁺), calcium (Ca²⁺) and magnesium (Mg²⁺) are increased in the soil, the soil become saline and alkaline. On the basis of amount of soluble salts, average quantity of exchangeable Na and pH, they are classified into 3 groups

Plant Nutrition

The term “fertility” refers to the inherent capacity of a soil to supply nutrients to plants in adequate amounts and in suitable proportions. Nutrition in plants may thus be defined as a process of synthesis of food, its breakdown and utilisation for various functions in the body. There are two types of nutrition:

1. Autotrophic nutrition: It is a type of nutrition in which the living organisms manufacture their own organic food from simple inorganic raw materials. The green plants exhibit autotrophic mode of nutrition and hence called the autotrophs.
 
2. Heterotrophic nutrition: Certain non green organisms like fungi and many bacteria fail to synthesize their own organic nutrients from inorganic substances.  These organisms are thus dependent on some other external sources for their  nutrition. Such plants are called heterotrophic plants and the mode of nutrition is called heterotrophic nutrition.

Plant requires food or nutrients or elements for its growth and development which are absorbed through soil. Adequate supply of plant nutrients is important to ensure efficient crop production. Plant nutrients are essentially applied through manures and fertilizers. Application of manures and fertilizers to the soil is one of the important factors which help in increasing the crop yield and to maintain the soil fertility. 
Manures
Manures are plant and animal wastes that are used as source of plant nutrients. They release nutrient after their decomposition. These are relatively bulky materials, such as animal or green manures, which are added mainly to improve the physical condition of the soil, to replenish and keep up its humus status, to maintain the optimum conditions for the activities of soil micro-organisms and make good a small part of the plant nutrients removed by crops or otherwise lost through leaching and soil erosion.

Water is indispensable for human, animal and plant life. Water is essential part of protoplasm. It is essential for photosynthesis. About 400 to 500 litres of water is necessary for the production of  a kilo of plant dry matter.
 
Irrigation

It is the human manipulation of hydrological cycle to improve crop production and quality and to decrease the economic effects of drought. Israelsen and Hansen (1962) defined irrigation as the artificial application of water for the purpose of supplying moisture to plant growth.

Out of 143 million hectares of net cropped area, about 75% is rainfed which contribute about 45% of food grains. These areas produce 55% rice, 25% wheat, 91% coarse cereals, 75% of pulses, 81% oilseeds and 69% cotton. More than 90% of sorghum, millet, groundnut and pulses is contributed from arid and semi-arid. The term rainfed farming (Dry farming) and dry land farming may be defined as conditions where rainwater is the only source of moisture for survival and growth of crops.

A. Write True or False
    1.    Bulk density is the true density of the soil.
    2.    Igneous rocks are acidic in nature.
    3.    Adhesion is the attraction of like molecules.
    4.    pH is the negative logarithm of Hydrogen ion concentration.
    5.    Limestone is a sedimentary rocks.
    6.    Size of the gravel is more than 2mm.
    7.    Black and dark colour of soil is due to organic matter and iron.
    8.    Soil moisture tension at Permanent wilting point corresponds to 15 atm. 
    9.    Micropores are the large pores present in the soil.
    10.    Oxidation is the removal of oxygen from the minerals.
    11.    Straight fertilizer contains only one nutrient.

Several centuries ago, perhaps as early as 6000-8000 BC, ancient man learned to domesticate species of animals for obtaining milk for their consumption. These included cows, buffaloes, sheep, goats, and camels, all of which are still used in various parts of the world for the production of milk for human use. The significance of milk as the most wholesome single food available in nature has never been debated. It is as ancient as mankind itself. The role and consumption pattern of milk in the traditional diet varies widely in different regions of the world. The tropical countries have not been traditional milk consumers, whereas in Europe (especially Scandinavia) and North America, milk and milk products have been traditional parts of the diet.

Definition

It is one of the important portion of milk which forms a fatty layer on top of milk when left un-disturbed. It is a prime component of milk and comprises mainly of milk fat. It may be defined as “that portion of milk which is rich in milk fat” meaning portion of milk into which larger portion of milk fat has been gathered.  According to FSSAI, 2011 Malai and Cream are defined as –

Malai means the product rich in butter fat prepared by boiling and cooling cow or buffalo milk or a combination thereof. It shall contain not less than 25.0 per cent milk fat.

Introduction
Makkhan (Makhan) is an indigenous(desi) butter obtained by hand churning of dahi using wooden beater (mathani). It is traditional unsalted butter characterized by its delectable and rich flavour. It is white in colour with slightly greenish tinge and has typical soft body and a smooth grainy texture with pleasant aroma. This product has been extensively used for dietary and religious practices since vedic times. The entire quantity produced forms an intermediate product for preparation of ghee (clarified butter fat). Nearly 30% of the total milk production goes for desi butter manufacture. The average yield of the product is very low ranging from 5.5-7.0% for every 100 kg milk used for the purpose. The chemical composition of the product is variable depending upon the method of manufacture. It is difficult to achieve the uniform standard of 20% moisture in the final product due to limitations in the technique adopted for its manufacture. The non fatty solids and lactic acid are derived from the method of preparation and preservation. Higher non fatty solids in makhan indicates use of self soured milk, while a high lactic acid content indicates prolonged storage and in sanitary conditions of manufacture.

Butter is one of the leading milk product in developed countries of the world. It serves as a balance wheel of dairy industry. Surplus milk is generally converted into butter to be used during the times of scarcity. It is an article of commerce and a sign if wealth. Butter is a fat concentrate, which is obtained by churning cream, gathering the fat into a compact mass and then working it for proper distribution of moisture and salt. The art of butter making has a long history. The manufacture of butter was confined to colder regions where gravity creaming was successful. The milk was allowed to stand undisturbed for 10-12 hours until layer of cream collects at the top.

Introduction

The demand for butter as table spread has declined due to high cost, poor spreadability at low temperature, high saturated fat and cholesterol content, changing life style and increased demand for healthy products. Today food industry is actively involved in new product development, this includes new formulations and imitation of foods being designed to compete with or replace existing products based on their superiority in convenience, cost and quality. The wide acceptance of bread in regular diet among urban consumers (75 percent of all household) reflects around 8 percent rate of growth in bread consumption. With this increase, the requirement of a suitable spread to complement has also increased. Table spreads include a variety of spreadable semi-solid products such as fat spreads, cheese spread, peanut butter etc. Butter has also been blended with vegetable oils/fat to produce a product that retains dairy qualities of butter with enhanced spreadability.

Introduction
Ghee is the pure clarified butter fat prepared chiefly from cream and/or desi butter (Makhan) to which no colouring matter is added.  Ghee manufacture has great significance and relevance to Indian masses and the dairy industry. Ghee is a very popular product since ancient time and has greater demand during festival and other ceremonial functions where use of ghee in food has been considered to delicacy due to its pleasing flavour and aroma. There are sufficient recorded evidence to prove that the manufacture of ghee originated from India and has been used extensively for religious and dietary purposes since Vedic times. Presently about 28% of total milk production is utilized for manufacture of about 1 million tones of ghee per annum. It is the traditional product with an established market. Cow ghee is golden yellow in colour, and is attributed unique therapeutic value.  The colour of buffalo ghee is greenish yellow due to presence of pigments called billirubin and billiverdin. Ghee is characterized by its pleasant, cooked and rich flavour. The preferred texture is of larger uniform size from grains having non-greasy consistency.

Introduction

In the recent past there has been a great deal of questioning regarding role of milk fat in cholesterol metabolism and other body functions. The enormous wave against cholesterol containing foods has damaged the image and market growth of fat rich dairy products. This trend is due to presence of saturated fats and cholesterol that are known to increase the incidence of coronary heart diseases one of the common cause of heart attack. The educated and urban society is more health conscious about the presence of cholesterol in their diets. This has led to the greater demand of cholesterol free foods. Ghee being a saturated fat and containing little amount of cholesterol, is suspected to contribute towards coronary heart diseases. However, critically surveyed scientific literature indicates that there is no evidence of any association of milk fat with increased risk of coronary heart diseases. Age old and proven Ayurvedic system of medicine has proved the usage of ghee to induce several beneficial effects on human health and used extensively for therapeutic purpose like in treatment of skin allergy, respiratory diseases, curative for ulcers and eye diseases. This suggest that ghee is a valuable form of dietary fat.

Introduction

The economic choice of any process is the criterion for efficient utilization of the by-product that is produced along side of main product. During manufacture of major dairy products, the dairy industry also ends up in producing different by-products. Various by-products of dairy industry are skim milk, butter milk , whey and ghee residue. Dairy industry is particularly confronted with the problem of economic utilization of whey and ghee residue. The techno-economical problems associated with utilization of these by-products, is now receiving considerable attention. More efficient, cost effective and sophisticated technologies have opened up new vistas for manufacture of number of derived by-products. Further more the market for dairy by-products, as an ingredients in other consumer food products like snacks, ready meals and microwavable food products, has been growing.

Over the past several years, there has been significant change in consumer perception on quality and food safety. Consumers are demanding healthy, nutritious and cost-effective products processed under controlled hygienic conditions. Food safety concern, in recent years, has become dominant and important. The requirement of food safety and quality assurance has never been so demanding as it is now. Globally food safety is being addressed independent of food quality. In anticipation of consumer demands on food safety, food sanitary standards at national and international levels are under constant review. Several inter governmental agencies/organizations are engaged in work related to quality assurance and food safety. Amongst these World Health Organization (WHO) and Codex Alimentarius Commission (CAC) play the major role in protecting public health and defining standards of quality and safety aspects of foods for regional and or world wide usage.