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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.