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Adverse climatic conditions like temperature, humidity, frost etc. affect vegetative growth, flowering, fruiting as well as quality of horticultural crops. Tropical crops are usually more sensitive to low temperature and frost injuries whereas temperate crops are vulnerable to high temperature effects. High temperature beyond tolerable limits may cause sunscald, tip dieback, bud death and heartwood damage. On the other hand, when temperature drops below the freezing point; water molecules ice formation in the intercellular spaces takes place showing freezing injuries on various plant parts. The symptoms like dehydration and necrosis are visible on plant due to increased concentration of sugars within the cell causing reduction in the water content. The extent of damage will depend upon the prevailing low temperature and its duration. Exposure of the plant near freezing temperature for prolonged time causes death of the plant due to formation of ice crystals in intercellular spaces.

It is difficult to define ‘stress’ precisely. In engineering and the physical sciences, it is usually defined as the force applied per unit area. But as far as in biology, stress it is usually described more loosely as any factor that disturbs normal functioning of an organism. Any environmental factor potentially unfavorable to plant is termed as stress.

The effect of stress on plant condition is called strain. Stress is the action, whereas strain is the reaction. Stress may be defined as external conditions that adversely affect growth, development and productivity. Stress may further classified as:

• Zero stress: This is the level of exposure of plants to environmental factors that leads to neither injury nor reduction in growth and yield of crops.
• Stress escape: Capacity of the plant to complete its life cycle during wet season before onset of stress.

In India, some of the major horticultural crops productivity is affected by major problems. Some of these have been overcomed by certain control measures strategies. However, a few of them are long lasting and have attained the status of national problems. These are mango malformation, alternate/biennial bearing, spongy tissue in mango, bunchy top of banana, guava wilt, citrus decline, rootwilt of coconut and yellow leaf disease of arecanut.

Mango malformation: Mango malformation was reported for the first time from Darbhanga, Bihar. The disease is more prevalent in northwest than northeast and south India. This disorder is widespread in flowers and vegetative shoots.Three types of symptoms are mainly observed. These are bunchy top phase, floral malformation and vegetative malformation. Bunchy top phase is observed in nursery, bunching of thickened small shoots, bearing small rudimental leaves. Shoots remain short and stunted giving a bunchy top appearance. In vegetative malformation, excessive vegetative branches of limited growth are observed in seedlings. 

oilless culture is a method of growing plants without soil. It is an artificial means of providing plants with support and a reservoir for nutrients and water. The simplest and oldest method for soilless culture is water culture or solution culture, where inorganic chemicals are dissolved in a vessel containing water to supply all the nutrients to plants. This method was originally termed hydroponics (water working) by W.F. Gericke in the 1930s. Over the years, hydroponics has been used sporadically throughout the world as a commercial means of growing both food and ornamental plants. Today, it is used widely in research facilities as a technique for studying plant nutrition.

Gravel or sand is sometimes used in soilless systems to provide plant support, and retain some nutrients and water. The retention of nutrients and water can be further improved through the use of sphagnum peat, vermiculite, or bark chips. These are the most commonly used materials, but other material such as rice hulls, bagasse (sugarcane refuse), sedge peat, and sawdust are used sometimes as constituents in soilless mixes.

Plastic has now become an integral part of horticultural production at various stages from nursery to marketing at consumers’ door during the last two decades. It is used at each and every stage of horticultural life cycle right from seeds packaging, nursery seedling raising, planting, propagation, mulching, irrigation, harvesting, fruit packing, preservation and marketing. The application of plastics in the agriculture sector is popularly known as Plasticulture.In 1948 Professor E.M. Emmert built the first plastic greenhouse, a wooden structure covered with cellulose acetate film. He later switched this to a more effective polyethylene film. After the introduction of plastic film to agriculture, it began being used at a larger scale around the world by the early 1950s to replace paper for mulching vegetables. By 1999 almost 30 million acres worldwide were covered in plastic mulch.

The word ‘organic’, means ‘living’, ‘earth friendly’ or ‘of plant or animal origin’. Organic farming is a very native concept of India and has been followed from ancient times. Soil is a living entity and the focus in organic farming is the soil itself. Of course, it is based on understanding the ways of nature. All organic waste from agriculture and other sources is recycled to enrich the soil. Thus, the health of the soil and its structure is maintained. The natural microorganisms of the soil are protected and nurtureed.

Organic farming is primarily aimed at cultivating the land and raising crops in such a way to keep the soil alive and in good health by use of organic wastes and other biological means of sustainable production in an ecofriendly pollution free environment.

As per the definition of the United States Department of Agriculture (USDA) study team; organic farming is a system which avoids or largely excludes the use of synthetic inputs namely fertilizers, pesticides, hormones, feed additives, etc. and to the maximum extent feasible rely upon crop rotations, crop residues, animal manures, off farm organic waste, mineral grade rock additives and biological system of nutrient mobilization and plant protection.

Orchard management is one of the important aspects in the horticulture industry. Success of orchards is mostly depends upon economic utilization of natural resources namely land, water, trees and other external inputs. All these resources have to be well utilized to the best advantage for higher production per unit area on a sustainable basis without adversely affecting the quality of the environment. Important aspects of orchard management are related with soil and water conservation, canopy management, nutrition management, weed management, plant protection measures, biotic and abiotic stress management, maturity and harvest, post harvest handling, utilization and marketing.

Soil management: Soil management aims at maintaining the fertility and productivity of soil. It creates favorable conditions for moisture supply, proper drainage and nutrient availability. It helps to maintain high fertility level and replenishment against losses, gaseous exchange, microbial activities, it helps to check soil erosion, suppress the weed population, economic utilization of interspace of main crops. Common soil management practices are cultivation, sod culture, mulching and rotation.

A cropping system refers to the type and sequence of crops grown and practices used for growing them. It is based on the available technologies of crop production. Cropping systems have been traditionally structured to maximize crop yields. Now, there is a strong need to design cropping systems, which take into consideration the emerging social, economic and ecological or environmental concerns for each ecosystem. The goal of a cropping system must be to conserve natural resources i.e. soil, water and sustain crop production. Conserving soil and water and maintaining longterm soil productivity depend largely on the management of cropping systems, which influence the magnitude of soil erosion and soil organic matter dynamics. Crop diversification is an important option in sustainable agricultural systems. Management of cropping systems implies management of tillage, crop residue, nutrients, pests, and practices for soil conservation. Difference between dry land and rainfed farming is as follows.

Major industries constituting the food processing industry are grains, sugar, edible oils, beverages and dairy products. The key sub-segments of the food processing industry in India are dairy, fruits and vegetables, poultry and meat processing, fisheries, food retail etc. Agro processing is the sunrise sector of the Indian economy in view of its large potential for growth and likely socio economic impact specifically on employment and income generation. India has the advantage of being one of the fastest growing economies in the world and it is the largest producer of several agricultural commodities. The food processing sector ranks first in terms of employment and number of factories in operation and third in terms of output.

In India, out of the total production of fruits and vegetables, nearly 76 per cent is consumed in fresh form, while wastage due to improper post harvest accounts for 20 to 35 per cent. Only around 2 percent of vegetables and 4 percent of fruit production are being processed. 

Flower is symbol of beauty and by nature attracts every human being. It is a gift of nature to humanity. Flowers symbolize the quintessence of human spirit. In India, losses are estimated to be more than 30-35%. It is due to the lack of knowledge of postharvest management of cut flowers. Several factors at pre harvest stage including genetic or inherent, climatic or environmental and management harvest factors like stage, method, time of harvesting and postharvest factors such as watering, rehydration, precooling, storage environment, packaging techniques and microorganisms influence the postharvest quality and longevity of cut flowers.

Preharvest factors

1. Genetic or inherent makeup: Postharvest lasting quality of flower species and cultivars vary considerably due to differences in their genetic make up. It is therefore desirable to grow cultivars, which possess long vaselife. 

Maturity can be defined as the attainment of a particular size or stage after which ripening takes place. It is also called physiological maturity. However,horticultural maturity is defined as the stage of development, when a plant or plant part possesses the prerequisites for utilization by consumers for a particular purpose. Mango, tomato, cucumbers, lettuce, peppers, etc. are harvested at various stages depending on the objective of disposal (horticultural maturity) prior to reaching physiological maturity, or completion of growth phase.

Maturity indices are the most important for deciding the stage of harvesting and to reduce post-harvest losses. The post harvest life of fruits are mainly controlled by maturity. Maturity signs are also called maturity standards or maturity indices. Maturity signs help in judging maturity of fruits and vegetables. There are many methods to determine maturity. The most common is the size and shape of fruit, change in colour, softening of tissues (fig, sapota), ease of detachment from the stalk (sapota, annona), shriveling of fruit stalk (watermelon), drying of nearest tendril (watermelon), days from blooming to picking maturity, sound by tapping jack and watermelon, when ripe produce hollow and dull sound on tapping but produce metallic sound if unripe etc.

India has achieved tremendous increase in horticulture production after independence. Adoption of several production technologies developed by several agricultural universities across the countries boosted the production of the horticulture sector both by increasing area under various fruit crops as well as by elevating productivity. Though the country has acquired second position in world fruit production; the productivity is less than many under developed countries.Several reasons can be attributed for declining productivity; few of them are enlisted below.

• Cultivation of old and less bearing varieties
• Improper and unscientific management of fruit crops
• Large number of old and senile orchards with declining productivity
• Problems in flowering and fruiting due to aberrant climate especially during flowering and fruiting

When fruit trees grow naturally; canopy varies greatly from species to species and cultivar to cultivar. It is mainly due to climate, planting density, rootstock, method of propagation, training, pruning, regularity of bearing, soil type, nutrition, irrigation, intercrop, growth regulators used, diseases, pests, environmental pollution etc. Plant canopy means the spread of branches and foliage of a plant.

Canopy management of the fruit tree deals with the development and maintenance of their structure in relation to the size and shape for the maximum productivity and quality. The basic concept in canopy management of a perennial tree is to make the best use of the land and climatic factors for an increased productivity in a three dimensional approach. Ideal canopy means fruit trees should have adequate number of fruiting units, it allows sufficient light and ventilation in to canopy and it should support adequate foliage and protect the fruits from sunburn. It should avoid overlapping of foliage to minimize parasitic leaves. It offers scope for effective coverage of sprays. It should avoid the buildup of microclimate, congenial for pest and diseases development. Tree vigour, light, temperature and humidity play a vital role in the production and quality of the fruits.

Fruit drop is a natural phenomenon, which occurs in most of the fruit crops. Fruit trees usually bear a large number of flowers and only a very small percentage leads to harvesting of fruits. Fruit drop occurs at various stages of maturity of fruit development. It is an adjustment of tree to its resources. Such drop is natural and beneficial to the trees and it will prevent exhaustion of the resources and breaking of branches by overbearing. The fruit drop usually takes place in definite waves or at a definite stage and those are presetting, post setting, jar drop and pre harvest drop.

The first drop i.e. presetting occurs immediately after flower opening. Usually male flowers as well as female/ hermaphrodite flowers with aborted pistil drop off at this stage.

Second drop i.e. post setting occurs a fortnight later than the first drop. This drop includes unfertilized flowers as well as some fertilized flowers drop as a result of adjustment in the trees between nutritional factors arid fruit set.

Unfruitfulness is a major problem in many fruit crops and their varieties. ‘Fruitfulness’ refers to the state, where a plant is not only capable of flowering and bearing fruit but also takes these fruits to maturity. The inability of plant to reach the fruits to maturity is known as ‘unfruitfulness’ or ‘barrenness’. In spite of adequate flowering, low fruit yields in orchards have been experienced because of low initial fruit set and subsequently higher fruit-let abscission. In an orchard, all the trees do not bear fruits equally or regularly and sometimes fail to flower and bear fruit under similar conditions, where another fruit tree bears heavily. This failure to fruit may be attributed to unfruitfulness. It is associated with internal and external factors.

Internal factors: These are as follows.

Alternate bearing or biennial bearing is a term used in fruit crops to refers to trees that have an irregular crop load from year to year. It is a major problem in some of the fruit crops. Long term studies of flower and fruit production in some of the fruit crops demonstrated that the majority of shoots on a tree bear flowers and then fruits in one year, i.e. a greater than average crop and the next year most of the shoots will produce only leaves resulting in a smaller than average crop.Thus, it is characterized by heavy crop load in trees i.e. on year, followed by a light or no subsequent crop load i.e. off year. When on and off year sequence does not follow a systematic pattern it is called periodicity of cropping or irregular bearing. Phenomenon of alternation is more prominent in the perennial fruit crops particularly Anacardiaceae (mango, Pistachionut), Carylaceae (hazelnut), Oleaceae (Olives), Rosaceae (apple, Pear, Plum, Apricot, etc.), Rutaceae (orange, tangor, satsuma, etc.) and also in tamarind, Jamun etc.

In general, plants show two distinctive phases; i.e. vegetative growth and reproductive growth. The primary objective of plant species is to reproduce themselves through the reproductive phase. However, some of the plant species do not produce viable seeds, but reproduce themselves in nature by other means. Flowering and fruiting habits vary with plant species and are governed by the kind of plant species and its growth habit, environment etc. In general, flowering and fruiting habits are known as bearing habits and it can be described by the location and type of buds, which produce flowers and fruit. The relative position of fruit with reference to its potential bud-giving rise to flower or inflorescence on the shoot is known as bearing habit. Each plant has its own bearing habit and are either terminally, laterally or adventiously Terminally means the fruit buds are formed on long or short growth, while laterally means the fruit buds are formed in the axils of present or past season’s growth. Adventiously, the fruit buds are formed at any point on the trunk. On the basis of bearing habits, fruit crops are categorised into the following eight groups

Among many factors influencing fruit bud formation, the relative proportion of carbohydrate and nitrogen in a tree appears to be the only factor that could be controlled by an orchardist. When under normal course tree does not flower; special practices such as ringing, girdling, stripping, notching, bending, water stress (with holding irrigation), root pruning and root exposure etc. are performed with the aim to control the translocation of food like carbohydrates, starch and sugars. Accumulation of food in the branches leads to fruit bud formation resulting into fruitfulness. Before performing the special horticultural practices, the orchardist should know natural growth habit of the plant, time of new vegetative growth and flowering, when it ceases to grow vegetative and mature its woods and when it takes rest

The term bio-fertilizer is related with such microorganisms that they add, conserve and mobilize the plant nutrients in the soil. Excessive use of nonrenewable exhaustive petroleum product based chemicals in horticultural production system has residual effect on soil, environment and human health. Use of biofertilizers is ecofriendly, cost effective and organic based inputs such as botanical pesticides, FYM, vermicompost, biogas slurry, disease and pest resistant varieties in cultivation of horticultural crops for safeguarding soil health and quality production.

Biofertilizers are microorganisms, which are capable of mobilizing nutrients from unavailable form to available form through biological process. They are not only cost effective but also inexpensive source of plant nutrients. They do not require non-renewable source of energy during their production. Besides, improving crop growth and quality of the product by producing plant hormones and help in sustainable crop production through maintenance of soil productivity. They are also useful as biocontrol agents, as they control many plant pathogens.

The plant growth regulators are the organic compounds other than the nutrients, which accelerate, inhibit or modify the various physiological processes in the plant system, when applied at low concentration. These growth regulators are readily absorbed and move rapidly in the tissues, when applied to the plant system and regulate its life processes in some beneficial ways to enhance the yield and improve the quality of the fruits.

The word hormone is derived from Greek, meaning set in motion. The five major phytohormones are auxins (indole-3-acetic acid and its derivatives), gibberellins, cytokinins, abscisic acid and ethylene. The key difference between plant hormones and plant growth regulators is that plant hormones are natural, while plant growth regulators are artificially synthesized and are applied to plants. Plant hormones are also called phytohormones. Plant hormones are the organic chemicals, which are synthesized by plants themselves naturally during the metabolic processes.These are synthesized at the given site and translocated to the site of action.

Vermicompost is the product of the decomposition process using various species of earthworms, to create a mixture of decomposing bedding materials and vermicast.

This process is called vermicomposting, while the rearing of worms for this purpose is called vermiculture. Vermicast is also called worm casting, worm humus, worm manure or worm faeces and are the end product of the breakdown of organic matter by earthworms. It is a mesophilic process and certain species of earthworms are used to enhance the process of organic waste conversion and produce a better end product. Vermicompost is an excellent organic fertilizer having water soluble macro as well as micronutrients, growth promoters, enzymes and soil conditioner, helpful for growth and development of plants. It helps to improve biological, chemical and physical properties of the soil.

The importance of green manuring in crop production has been known since ancient times. However, awareness towards soil enrichment is increasing in recent years, mainly due to comparatively high cost of inorganic fertilizers, increased risk of environmental pollution and need of sustainable cropping systems. Green manuring helps to improve physical, chemical and biological properties of soil and consequently crop yields. Green manuring lowers the nitrogenous fertilizer requirements for succeeding crops. However, it’s influence may vary with soil, crop environmental variables, type of green manure crop used and its management.

Green manuring is a practice of ploughing or turning into the soil un-decomposed green plant tissues for the purpose of improving physical structure as well as fertility of the soil. It is obtained in two ways; by growing green manure crops or by collecting green leaf (along with twigs) from plants grown in wastelands, field bunds and forest. Green manuring by growing the field plants usually belonging to the leguminous family and incorporated into the soil after sufficient growth. The most important green manure crops are sunnhemp, dhaincha, Pillipesara, cluster beans and Sesbania rostrata. The advantages of green manuring are as follows.

It is not just enough to produce fruit and ornamental plants in a nursery, but it is also very much important to consider the post production management practices like harvesting, packing, storage and marketing of nursery plants for successful industry.

Harvesting: Harvesting is one of the important factors considered, when nurserymen are producing seeds, bulbs, etc. The seeds or bulbs should be harvested at proper maturity stages depending on the plant species.

Seeds are generally harvested when they are fully ripe. In some of the annuals and perennials, seeds are likely to fall from the plant at ripening either due to bursting of the fruit/ capsule or due to wind. (calendula, balsam). In such cases, it is better to cover with muslin cloth or butter paper bags. Bulbs, corms and tubers are carefully dug out without injury, along with cormels or bulblets.

Packaging: The package should provide a convenient mode used for marketing and distribution. It protects the contents from undue damage during distribution. It is important that appropriate packaging should be used to preserve quality of material along with maximum survival during transit. Proper packaging of plant material (fruit plants/ ornamental plants/seeds) ensures quality during storage, distribution and transport.

Potting and repotting is an essential practice to be done in a nursery to maintain the expected vigour of the plant. When a seedling from a seedbed or plant from a flat bed or raised bed is planted in a pot, it is called potting. The same term is utilized when the bulbs of bulbous plants are planted in a pot. When a plant is transferred from one pot to another pot, it is called repotting. At the time of repotting the plants may be planted in a large pot or in the same sized pot. Repotting is necessary when

1. Plant is grown for a season or a year in the same pot and becomes pot bound resulting in extensive growth of roots in rooting media and there is very little scope for further fresh growth.
2. When a plant is overgrown and requires separation or division.
3. When soil gets depleted of its nutrients.
4. Repotting affords an opportunity to the roots to form a new root growth, as repotted soil contains sufficient amounts of nutrients and good aeration.

The young seedling stock and rooted cuttings as well as nursery plants require proper care and nourishment. The operations to be performed regularly in nurseries are as follows.

1. Shifting of plants: The nursery plants grown in the pots or polybags are to be shifted once in 2-3 months to avoid root penetration into the soil. If the taproot penetrates deep into the soil, the chances of mortality increases. Hence shifting of grafts and potted plants has to be done at the said intervals
2. Removal of rootstock sprouts: Once has to keep a constant watch on the sprouts arising on the rootstock, which are to be nipped off as and when, observed, to encourage rapid growth of scion shoots.
3. Irrigation: The young tender seedlings are exacting in their water requirement. Proper and judicious irrigation is an important indicator of a healthy nursery, which solves many problems in the nursery. There are many methods adopted in nurseries. However, it depends upon water availability, kind of nursery plants and its growth stage, etc. These methods are flow or flood irrigation, furrow irrigation, overhead irrigation through rose cans, automizers or sprinkler systems, etc.

Facilities required for propagating many plant species by seed, cuttings, or grafting and budding include two basic units namely a structure with temperature control and ample light such as a greenhouse or hot bed where seeds can be germinated or cuttings rooted. The second unit is a structure into which the young tender plants can be moved for hardening preparatory to transplanting and cold frames or lath houses are useful for this purpose.Greenhouses: There are different types of greenhouse namely low cost greenhouse and commercial greenhouses. In all polyhouses/ greenhouses means of providing air movement and air exchange is necessary to aid in controlling temperature and humidity It is best, if possible, to have in the greenhouse heating and self-opening ventilators and evaporative cooling systems. Plastic greenhouses covered with various types of plastic film have become very popular among nursery men.

Nursery is one of the important components of horticultural crop production. Nursery is place where young crop plants are raised under intensive care for later transplanting to the field. Nurseries may be classified as follows. On the basis of the irrigation facilities, the nurseries are dry or wet nurseries.

1. Dry Nurseries: Generally such types of nurseries are observed in forestry. It is maintained without any irrigation or artificial watering. The rab nurseries of Western Maharashtra, Karnataka and Gujarat come under this category. The rab or semi-rab nurseries are made in the plantation areas on small well-burnt patches of land usually 0.01 to 0.05 ha mainly for supplying teak stumps. The seeds are sown in lines 45 cm apart just before the onset of monsoon. Normally no elaborate beds are made, no fencing is made and no irrigation is provided as compared to other nurseries.

The term micropropagtion is also known as tissue culture. Micropropagation refers to aseptic culture of various plant parts in artificial growth medium to produce new plant. This means is recently applied in propagation of horticultural crops e.g. Orchid, banana, strawberry, papaya, grape and many other plants.

Requirements for tissue culture: It includes basic facilities including equipment, asepsis, culture medium and culture environment.

• Basic facilities including equipment: Provision of working space, large sinks, washing machine to wash glassware, oven, dryers, dust free storage, space for glass house and chemicals, autoclave for sterilizing media, solutions, water culture and instruments, supply of distilled or deionized water and various essential instruments and appliances.

Many types of containers are used for growing plants in nurseries. These are clay pots, plastic pots, fiber pots, wooden pots, etc. Generally, the type of container to be used for growing a plant depends upon the kind of plant, objective of growing, choice of grower, etc. With advancement of technology, the container-grown plants are widely adopted, practiced by the nurserymen. The advantages of container grown plants are they are not prone to damage during packaging and transport. These are widely used for many fruit and ornamental plants. The different types of container and their characteristic features are as follows.

• Clay pots: Well-baked earthenware pots are used for raising plants. These are available in different shapes and sizes. On the basis of shape and size; these are named by pela, parali, kundi, nand, khobada, etc. Porous nature of the clay pots permits aeration, and water movement. Pot made with clay soil and well-baked will last longer than those made with sand or loamy soils. Before using, these are dipped in water for some period to soak the water in the pot itself sufficiently. However, earthen pots are heavy in weight, possibilities of breakage during potting and repotting and hence are less durable.

Media for plant growth and seed germination has great significance in nursery business. It is the basic need of the propagation industry. The material for rooting and growing media may be used either alone or incorporated with one or more products in combination. The materials used for rooting media may be naturally occurring or may be manufactured artificially.

Characteristics of an ideal rooting medium: These are as follows.

1. The medium must be sufficiently firm and dense to hold the cuttings or seeds in place during rooting or germination.
2. It must retain sufficient water and air, allowing sufficient drainage.
3. It should be highly decomposed and stable.
4. It must be free from weed seeds, insect pests and diseases.
5. Acidity or alkalinity should be the optimum for different species.
6. Its volume must be fairly constant, when either wet or dry.
7. It must be capable of being sterilized.

Plant propagation is one of the important fundamental aspects since the time of Rigveda (1400 B.C.) in the horticulture industry. It refers to the multiplication or perpetuation of individual or group of plants having specific value. Agriculture began, when ancient people started domestication of certain plants by growing around them and now these are cultivated in much improved form due to continuous selection and maintenance of better plant types. During the process of civilization; many plant types were selected for food and other purposes and are classified as food crops, fodder crops, fruit crops, vegetable crops, spices and condiments, aromatic and medicinal plants, etc. Now due modern plant sciences; newer and better plant types came into commercialization for cultivation. However, to maintain their qualities; it needs their propagation to keep their original form. Thus, it indicates that plant propagation has paramount importance in the horticulture industry to supply true-to-type sapling to farmers.

The term weed can be described in many ways. In general, it is said that weed is a plant, which is not sown by the farmers or which is out of place. Weed is defined as the unwanted, undesirable plant, growing out of its proper place, which interferes with the utilization of natural resources, is prolific, persistent, competitive, harmful and even poisonous in nature and can grow in adverse climatic conditions.There are more than 30,000 species of weeds distributed world over, out of which 18,000 are noxious and cause serious losses. Around 250 species are causing serious economic losses. Weeds in orchards reduce crop yields by competing for moisture, nutrients, light and space. They also act as a host for insect pests and diseases. When they become large, they interfere with orchard operations as well as water bodies. There are some weeds, which are parasitic partially or completely on the host tree e.g. striga and loranthus, in mango.

Water is one of the most vital components for the successful growth and development of crops. It influences most of the plant metabolic activities, namely photosynthesis, respiration, absorption, translocation utilization of mineral nutrients, etc. Its stress or in excess affects the growth and development of a plant directly and consequently its yield and quality.

Role of water: Water plays an important role in plant growth and development in many ways.

• It is the chief constituent of protoplasm.
• It provides aqueous medium for various biochemical (metabolic) reactions.
• It serves as a temperature stabilizer and helps in maintaining a stable metabolic rate.
• It is an essential input for photosynthesis.
• It helps to maintain turgidity of cells and plant organs.
• It is an excellent solvent for various organic materials of cells.

According to the present state of our knowledge, sixteen-elements are considered to be essential for plant growth and development. These nutrients are chemical elements, which are absorbed by the plants in more or less quantity to transform light energy into chemical energy and to keep up plant metabolism for the synthesis of organic material. These elements are regarded as essential in higher plants.

These are Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Potash, Calcium, Magnesium, Sulphur, Zinc, Manganese, Copper, Iron, Boron, Molybdenum and Chlorine. Carbon, Hydrogen and Oxygen are obtained from air and water. Carbon makes up the great bulk of the plant and is obtained from carbon dioxide in the air. Hydrogen is derived mainly from the breakdown of water. Oxygen is obtained from air as well as water. Other thirteen elements are obtained from mineral and organic components of the soil. These elements are further grouped into major/macro and minor/micro-elements. The nutrients that are required in relatively larger quantities are termed as macro elements. Micronutrients that are required in relatively lesser quantities are termed as micro nutrients.

Fruits and vegetables are the major constituents of daily diet. They provide not only body building elements but also energy yielding food for the wellbeing of humans. Main object of the nutrition garden is to make availability of the requisite quantity of fresh fruits and vegetables to family members. It is generally raised in the backyard of home. It is also called as a home garden or kitchen garden. Most of the day to day cultural operations are performed by family members. Working in the nutrition garden during their spare time is a pleasure, an inspiration, a means of recreation to all the family members. The foremost advantage of nutrition garden is to daily supply fresh fruits and vegetables as per the needs of family members. Nutrition garden has an important role in enhancing national food security and dietary diversity to combat malnutrition.

Points to be considered, while the planning and layout of nutrition garden

Horticultural plants are grown for their diversified produce like fruits, vegetables, flowers, aromatic (essential oils) or medicinal components, spices (oleoresins), etc. if these plants are allowed to grow naturally, they will grow wild with very less potential yield. Therefore, it is essential to train and prune these plants not only to develop the proper framework in manageable shape but also to improve the potential yield in terms of quality and quantity.

Once the sapling is planted, it is essential to maintain the proper framework by cutting certain branches as well as some parts of branches. In the initial period, it is essential to maintain well distribution of flower or fruit bearing parts growing in four directions. Once the plant achieves proper framework after a certain period; then also some of the plant parts, namely branches or certain portions of branches, are removed to achieve potential yield.

India is regarded as a horticulture paradise due to growing of tropical, subtropical and temperate fruit crops in varied soil and climatic conditions. However, increasing pressure on land owing to diversion of orchard lands to various other obvious reasons as well as rising energy and land-costs, together with mounting demand for fruits have made HDP imperative to achieve higher productivity from limited space.

There is a shift in farmers’ perception from production to productivity and profitability, which can be achieved through high density planting. India is the second largest producer of fruits in the world. However, the average productivity of various fruit crops in the country is quite less. Low productivity can be attributed to many reasons such as old and senile orchards, lack of canopy management practices, planting of poor yielding varieties, low or no adoption of recommended package of practices by the farmer leading to poor orchard management, etc.

The system of planting to be adopted is selected after considering the slope of land, planting density, purpose of utilizing the orchard space, convenience, etc. Traditionally, six systems of planting are recommended for fruit trees. However, with the popularity of high density planting, there are some advances inplanting, especially in fruit crops.

1. Square system: This system is considered to be the simplest of all planting systems and adopted widely. In this system, the plot is divided into number of squares as per plant spacing and trees are planted at the four corners of each square, in straight rows running at right angle. Under this system, intercultural operations, spraying, harvesting, etc. can be done conveniently and easily. Cultivation and irrigation can be done in two directions. In this system, plant to plant and row to row distance is the same. e.g. 5x5m, 4x4m, 10x10m, etc.

   While laying out the plot, a base line is first drawn parallel to the road, fence or adjacent orchard at a distance equal to half the spacing to be maintained between the trees. Wooden pegs are fixed on this line at the desired distance. At both the ends of the baseline, right angles are drawn by following the simple carpenter’s 3,4,5 meter system. After the formation of three lines, it is easy to fix all the other pages to mark the tree locations at the required spacing by using ropes connecting the pages of the lines in opposite directions.

   Area occupied per plant = row to row distance X plant to plant distance

The selection of the site has great importance for the establishment of a fruit orchard successfully. Establishment of orchard is a long term activity with huge investment. Hence, any mistake committed during site selection, it is difficult to rectify it later. Successful orchard is not only related with yield but also its economic production and efficient disposal of produce. For economic orchard establishment; some of the points which need to be considered, while selection of site. These are as follows.

1. Climate and soil: These are two important natural factors, which decide the success or failure of orchards. Before selection of site, climate and soil requirement for selected fruit crops needs to be studied thoroughly and accordingly site must be selected. On the other hand if a site has already been selected; then fruit crop selection needs to be done as per the existing climate and soil of that selected site.
2. Topography: Slope of site more than 15% makes the land almost unsuitable for cultivation. Land with 4% slope may be kept clean without much loss. Uneven land involves heavy expenditure in leveling. Southern slopes are generally warmer and affect the plant growth in a manner different from the northern slopes. It is due to the difference in quantum of receiving sunlight. Hence, the site with southern slopes may be selected for sun loving plants.

Growth and development of any horticultural crop is mostly depending upon two chief natural factors i.e. climate and soil, which decides success or failure. Therefore, understanding about climate and soil requirements for different horticultural crops for optimum growth and development is a prerequisite for profitable farming.

There is often confusion between weather and climate. Weather describes the condition of the atmosphere over a short period of time e.g. from day to day or week to week. It is current atmospheric conditions including temperature, rainfall, wind, humidity, sky condition at a given place. Climate on the other hand, is the average condition of weather over a longer period of time. Climate is the sum of all the statistical weather information that helps to describe a place or region.

Climate includes different factors namely temperature (minimum & maximum),

Growth and development are two important stages in a plant. Plant growth and development are under the control of both intrinsic and extrinsic factors. Growth is one of the fundamental characteristics of all living things. Even in Plants, the growth is visible but not measurable easily. Development in plants is actually a sum of two processes i.e. growth and differentiation.

Principles involved in plant growth and development: The various principles involved in plant growth and development are discussed below.

1. Totiopotency: Living plant cell has the potential to reproduce all the characteristics of the plant since it possesses all the genetic information.
2. Competence: It is the potential of cells or tissue to develop in a particular direction. Development of competency into a particular kind of cell(s), tissue or organ also may require special signals. These may originate internally within the plant or may originate externally as an environment signal, e.g. Internal change in type of growing point such as vegetative to flowering or initiation of adventitious roots on cuttings may be associated with a shift in the activity of specific hormones, external parameters i.e. application of growth regulators, or environment. It is mainly internal potential of meristem that gradually shifts from a vegetative shoot to one that produces flowers.

Anatomy is the study of an internal structure of an organism, while morphology is the study of various external features of an organism Anatomy helps in knowing the structural peculiarities of different groups of plants, which help for adaptation to diverse environments. An angiosperm plant is characterized by the presence of roots, stems, leaves, flowers, and fruits

Plant cells: Plant cells are multicellular eukaryotic cells that make up a plant (a group of eukaryotes belonging to the Plantae kingdom, with the ability to synthesize their own food using water, sunlight and CO₂). Being eukaryotic cells, they have a defined nucleus with specialized structural organelles that enable it to function in an orderly manner.

Grouping plants in different categories on the basis of similarities and dissimilarities is referred to as classification, which helps for study of these crops in various perspectives. India is endowed with a rich diversity of horticultural plant wealth due to varied agro-climatic conditions. Number of fruits, vegetables, ornamental crops, spices, condiments, plantation crops, etc. is under commercial cultivation in different parts of the country under different sets of growing conditions.

The systematic study of all these crops becomes a difficult and more repetitive part. To avoid it; classification of horticultural crops on different aspects has been made to deal with all these plants separately. Classification of horticultural crops has been made in different groups on similarity or dissimilarity of attributes. Plants having similarity in either of the traits are placed under one group. The overall objective of the classification is to categorize the horticultural plants and make the recollections very easy and convenient.

Horticulture includes variety and diversity of crops. Thus, it can be divided into several branches depending upon the crops it deals with. Following are the branches of horticulture.

1. Pomology: The term pomology is a combination of two Latin words pome i.e. fruit and logos i.e. science. Recently it has been designated as ‘Fruit Science’. It deals with the study of fruit crops. It includes all aspects of fruit crops e.g. importance, uses, origin and distribution, area and production, soil and climate requirement, botany, nursery raising, cultivation practices, plant protection measures, stage and methods of harvesting, post-harvest handling, marketing, export, import, etc. e.g. mango, banana, citrus, grape, apple, peach, pomegranate, fig, etc.
2. Olericulture: The term olericulture is also derived from the Latin word. Cultivation of vegetable crops. Recently it has been designated as ‘Vegetable Science’. Vegetables are said to be herbaceous plants of which edible plant parts are used for consumption either cooked or salad. It may be stem, root, leaf, flower, etc. It also includes all aspects of vegetable crops e.g. importance, uses, origin and distribution, area and production, soil and climate requirement, botany, nursery raising, cultivation practices, plant protection measures, stage and method of harvesting, post-harvest handling, marketing, export, import, etc. e.g. tomato, brinjal, chilli, cucumber, red pumpkin, watermelon, cabbage, cauliflower, etc.
3. Ornamental Horticulture: It includes various groups of ornamental plants used to decorate in-door and out-door areas. Ornamental horticulture is the study of growing, arranging and tending decorative plants and flowers. It is further divided into.

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

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

Healthy body maintains a healthy mind. Fruits and vegetables are said to be protective food as they provide proteins, carbohydrates, fats, vitamins, minerals, roughages, organic acids, enzymes and energy for normal growth and sustenance of physiological activities of human beings. Fruits and vegetables provide palatability, taste and improve appetite. It also provides fiber to prevent constipation. They reduce the ill-effect of acids produced during digestion of proteins and fatty acids. Thus, they protect the human body from various deficiency disorders.

Important fact is that most of the Indians are vegetarians. The incorporation of fruits and vegetables in daily diet is essential as body building elements and calorie yielding foods for good health. Comparatively fruits and vegetables are the cheapest source of natural nutritive foods and are an important component of a balanced diet Balanced diet is a diet which contains body building elements and calorie yielding foods in an appropriate proportion for normal growth and well-being of a person. According to ICMR, New Delhi; 120 g fruits and 280-300 g vegetables should be consumed per day per capita. Vegetables include 80-100 g of leafy vegetables, 100-125 g of tubers as energy source and remaining as other vegetables.

Horticulture is of immense importance for human beings. Among these major ones are nutritional importance, economic importance, medicinal values, environmental balance, aesthetic value and recreation. These are as follows.

1. Nutritional importance: Healthy body maintains a healthy mind. Human body requires vitamins, minerals, proteins, energy, fibers, etc. for its health. Fruits and vegetables are the chief sources of proteins, carbohydrates, fats, vitamins, minerals, organic acids, fibers, etc. Consumption of fruits and vegetables keeps the human body away from several illnessess and hence are recognized as protective foods; necessary for the maintenance of human health. As per the Indian Council of Medical Research; consumption of at least 120 g of fruits and 280-300 g of vegetables per day per capita is essential. Among vegetables, 80-100 g of leafy vegetables, 100-125 g of tubers as energy source and reamaining as other vegetables. However, the consumption of fruits per capita in India is still low. In countries like Italy, France and USA; the daily fruit consumption is 308, 232 and 223 g respectively. 

The word ‘horticulture’ was first conceived by Peter Laurinburg. In an English language, the word horticulture used for the first time in 1678 in a book entitled “New World of Words” by Phillips. The term HORTICULTURE is resultant of two Latin words i.e. HORTUS meaning GARDEN and CULTURA meaning CULTIVATION.

The Latin term ‘Garden’ meaning to enclose. In past, the garden had protection with with walls or other similar structures. Such protected places were used to grow fruits, vegetables, flowers and ornamental plants. When fruits are grown in a definite area, that area is called as an ‘orchard’. Thus, horticulture refers to cultivation of garden plants in protected enclosures. It is an aesthetic science deals with the garden crops. Such as growing of vegetable crops in vegetable gardens; fruit crops in fruit gardens. The most distinguished character between horticulture and agriculture is that horticulture deals with small scale gardening and usually in enclosed gardens although this is not a necessity, while agriculture is done on large scale with extensive crop cultivation.

11.1. Origin and distribution

• Indigenous to Mediterranean region, growing wild in higher hills of Southern France, Italy and Bulgaria.

11.2. Economic importance

• True lavender (Lavendula angustifolia Mill sub. sp augustifolia)

• Spike lavender (Lavendula latifolia Mill sub. sp spica)

• True lavender - used in perfumery industry.

• Lavandin - hybrid between true and spike lavender

• Lavender oil - delightfully clean, refreshing and sweet odour.

• Main constituent - ester, linalyl acetate 30 to 60%

• Another compound - ethyl-n-amyl ketone.

• Free linalool - major component

10.1. Origin and distribution

• Native of Philippines

• Grows wild in Malaysia, Indonesia and Singapore.

• Natural habitat extends across Paruguay, Penang, East and West Indies, sub-tropical Himalayas and Deccan peninsula.

• Introduced into India by Tata Oil Mills

• Cultivated in Bangalore and coastal areas of South India, Bengal, Odisha and Assam.

10.2. Economic importance

• Oil of patchouli is called patchoulol. Oil contains benzaldehyde, eugenol and cinnamic aldehyde etc.