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India is bestowed with varied climatic conditions and a variety of horticultural crops are produced. It is estimated that 20-30% of the produce is lost before consumption because of various reasons including improper storage and this is where the need of processing for preservation arises. There are various ways of preserving the produce and various ways to process it.

Preservation is defined as methods of extending the shelf life of the produce in its original form or in a different usable form. The basic principle of preservation involves strategies which aim at reducing the spoilage. The horticulture produce is spoiled by microbial infection or infestation. Prevention of microbial damage can be achieved by keeping the produce away from microbes, by removing the microbes, obstructing the proliferation and by killing the microbes. Infestation in the harvested fruits may lead to other microbial infection and spoilage due to rotting.

Horticultural crops are highly perishable and the post-harvest loss is estimated to be 20-30% every year. There are various factors associated with post-harvest losses. It includes pre-harvest cultural operations, maturity index at which the produce is harvested, methods of harvest, pre and post-harvest treatments, packing materials and storage methods. Postharvest technology can be defined as the techniques which help to reduce the post-harvest losses.

Assessment of harvesting stage

Climate may be related to periodical events in plants life. The science dealing with this relationship is termed as phenology. The phenological data for horticultural crops include dates of planting, germination, flowering, fruit set, ripening and harvest. These dates are determined by the climatic factors prior to as well at the time of harvest. A useful phonological concept for the prediction of the harvest time is based on degree days. A “ Degree day” can be defined as a day when mean daily temperature is one degree above the minimum temperature for the growth of the plant. The minimum temperature for the growth of a particular plant is termed as “zero temperature”. Zero temperature vary according to crop. E.g. if zero temperature of a particular crop is 50°F, then a day with mean temperature of 68°F would provide 18° days. The degree days are also called as “heat units”. It can be determined by how many degree days are needed for the horticultural crop to reach harvesting stage.

Plants grow in the open in nature, hence are subjected to biotic and abiotic stress.

Biotic stress is due to living components such as:

Insects and pests

Nematodes, mites, snails, slugs etc.

Vertebrates like rats, birds, jackal, bats etc.

The plant experiences biotic stress when root, stem, bark, shoots, leaves, buds, flowers and fruits are damaged by the influence and activity of biotic factors.

Biotic factors Diseases

Like the pests, diseases also cause stress to plants. Diseases are caused by fungus, bacteria and virus. Sometimes the exposed part of insect eaten plant part becomes the entry pathway for fungus, bacteria and virus.

Horticulture is an art and science of growing plants. It is the practice of engaging ailing people in various horticultural activities such as gardening and flower arrangements in order to improve their physical, mental and spiritual health. Research confirms that health benefits escalate manifold when people connect with nature and plants by viewing and/or interacting with them. Major benefits of horticultural therapy includes sensory simulation and mood enhancement, mental relaxation, improvement of memory and concentration and an overall feeling of wellness. Horticulture therapy also helps in cultivating positive emotions and provides a meditative mood. It eases both physical and emotional pains and also improves social skills. It is proven that a simple viewing of a garden benefits a person both physically and mentally.

This practice has been used as therapy for centuries. In 1798, Dr. Benjamin Rush, considered as the “Father of American Psychiatry” documented that gardening has positive effects on mentally ill patients. Following World War, II gardening was used as a form of occupational therapy for war veterans. The concept of using nature to improve human health began to gain credibility in 1970’s. Rachel and Stephen Kaplan (1989) found that natural environments had relaxing and restoration benefits for people. The Journal of Therapeutic Horticulture, a peer-reviewed publication of the American Horticultural Therapy Association, has published authentic research papers since 1986. The American Horticultural Therapy Association (AHTA) serves to promote and advance horticultural therapy as a therapeutic intervention and rehabilitative approach. Degrees and certificate programs in horticultural therapy are offered at several colleges and universities and information is available on AHTA website.

Horticultural therapy is a worldwide practice and recognized as an effective treatment for clients of all ages and abilities. It is being used in several diverse settings including hospitals, rehabilitation centres, youth outreach and recovery programs, nursing homes, senior care facilities, prisons, mental health facilities, schools, botanical gardens etc. The client is engaged in horticultural activities facilitated by some trained therapists to achieve specific and documented goals. AHTA believes that horticultural therapy is an active process that occurs in the context of an established treatment plan where the process itself is considered as the therapeutic activity rather than the end product.

Horticulture therapy is a growing profession in rehabilitation and addiction centers, vocational centers, youth mental health programs, hospitals and nursing homes, and old age homes or senior citizen centers, mental health centers, schools and colleges.

Flowers of the garden are brought indoors to enjoy the beauty. Fresh flowers are arranged in various styles according to one’s choice. There are two major and distinct styles of arranging fresh flowers, namely the European and the Japanese. Both the styles are greatly influenced by the place where they have been originated. Flowers are also dried and used for different arrangements. Fresh flowers are used as ornaments and also for making floral patterns on the floor called Rangoli.

A garden has a number of elements which give shape to its breath-taking view. Both animate and inanimate elements are included to achieve a beautiful garden The living elements are lawns, rock garden, water garden, sunken garden, hedges, edges, shrubs, topiary, flower bed, specimen plants, pergola and arches, while the inanimate elements, also called as adornments, are stones, road, footpaths, seats, lamps, lanterns, steps, bridges, huts, swings, fountain, cascade, bird bath, clock tower, umbrellas, sculptures etc.

Micro propagation in also called as in vitro propagation. In vitro is a Latin word, meaning ‘in glass’. It refers to procedures done in controlled artificial environment, outside a living organism. These procedures naturally occur in the living system. Opposite to in vitro is in vivo which is also a Latin word, meaning ‘in living’. Biological processes that occur within the living system.

Micro propagation refers to the multiplication of plants, in aseptic conditions in containers under controlled nutritional and environmental condition. Micropropagation is done in artificial growth medium from various plant parts like meristem tip, embryos, anthers, axillary buds, leaf section, shootlips etc. It is a method by which a true to type and disease free plant can be regenerated from a miniature piece of plant throughout the year. Some popularly grown crops from tissue culture are as follows

Ornamental plants - orchids, lilium, gerbera, cordyline, begonia, ficus, etc.

A kitchen garden/ nutrition garden is a vegetable garden where the vegetable crops are grown in the backyard of a house or any available space in compound or rooftop of the house, to meet the daily requirement of the family. All the members of the family are collectively involved in a kitchen garden.

For a balanced diet, 300 g of vegetables are to be included in our daily food. But on an average, Indians take only 160 g per day. Hence to fill up the gap, vegetable cultivation not only in farmers’ holdings but also in the home gardens is encouraged.

Organic cultivation is a deep rooted cultivation tradition, which had been practiced in many parts of the world, before the advent of the practice of use of chemicals.

After the green revolution there has been exponential usage of chemicals in agriculture, right from planting to harvesting. Chemicals are used in the form of nutrient inputs or for plant protection against pests, diseases, weeds and keeping deficiencies at bay. Nevertheless, after the awareness regarding the detrimental effect of chemicals on soil, climate and human health, there has been a lot of contemplation on substituting the chemicals with the organic alternatives. Growing crops using organic inputs is known as ‘organic cultivation’. Organic cultivation is a sustainable form of cultivation where a proper balance is maintained and management of plant nutrition, pests, weeds and diseases is done in a sustainable manner, keeping the soil microflora intact and active. It does not release any chemical gases in the atmosphere, does not make the soil acidic and the soil does not lose its structure and texture. Contrary to chemical farming, where over a time period, the soil quality, texture and structure is lost, in organic practices, the soil texture, quality and structure improves over time, the plants become strong and the quality of the produce is improved. Other than organic inputs, organic farming relies on some sustainable practices like using native germplasm, crop rotations with legumes, green manuring, mulching, inter cropping, mixed cropping, incorporation of farm and animal waste compost. These simple age old practices build to organic content in the soil and elevate the soil’s efficiency to make nutrients and water to the plants. The soil microflora and earthworms become biologically active, efficient and exponentially proliferate. The goal of organic cultivation is to get maximum produce from the soil in such a manner that the soil, air and water are clean and protected.

GAP stands for “Good Agricultural Practices” which are used for production of safe agricultural produce which has zero microbial load on it and inside it. It is important for the producer to be acquainted with GAP.

Good Agricultural Practice of horticultural crops are intended to apply to the growing and processing of all produce as traded and used in the European Union. Hence, they apply to the production of all plant materials used in the food, feed and medicinal industries. They also apply to all methods of production including organic production in accordance with the European Union regulations.

The farmers involved in the cultivation of horticultural produce should ensure that the there is no damage to the existing wild life and the biodiversity in the farms which are maintained. It is advisable to regulate wild gathering by a specific guideline.

The main aim of GAP guidelines is to ensure that the produce meets the demand of the consumer and is of high quality standard.

It is therefore, important that they are produced hygienically, in order to reduce microbiological load to a minimum. They are produced with care, so that negative effect on plants in the course of cultivation, processing and storage is limited.

All participants in the production process are required to comply with these guidelines voluntarily and to develop practical measures to achieve it.

Greenhouses are frames or inflated structures covered with a transparent or translucent material in which crops can be grown under partially controlled or totally controlled conditions of atleast. It is large enough to permit persons to work within, to carry out cultural operations. Greenhouse cultivation as well as other modes of controlled environment cultivation has been evolved to create favourable microclimate, for the crop production all through the year or during off season, when the produce is highly priced and remunerative. Green house is a broader term of protected structures which includes different types of structures according to the need. Green houses vary in size and complexity from small home or hobby structures to large commercial units, from solar green house to sophisticated environment controlled ones.

Plant growth regulators are defined as chemicals other than nutrients and vitamins which regulate (or) modify the physiological process ofthe plant. A plant hormones or phytohormones are chemical substances which are naturally produced by plant in specific organs and are translocated from site of synthesis to the site of action. They bring about specific physiological response, even in very low concentration. The quantity of synthesis of these hormones differ from plant to plant, plant internal and external factors. They are readily absorbed and these chemicals move rapidly through the tissues when applied to different parts of the plant. A plant growth hormone may be termed as a plant growth regulator, but not vice - versa, since other than natural plant hormones, plant growth regulators are synthetically manufactured chemicals.

Plant growth regulators have a diverse chemical composition. Based on the general response the chemical mediates in the plant system, they are classified as growthpromoters and growth inhibitors/retardants. However, a particular growth regulator may be growth promoter at a lower concentration and growth inhibitor at higher concentration.

The term growth refers to an irreversible increase in size and weight of the plant. It normally reflects an increase in protoplasm, which may occur through increase in size of the cell and number of cells. Hence, the process of cell elongation and cell division provides the basis for growth. Cell division and enlargement are complicated processes involving synthesis of many organic compounds such as protein, cellulose and nucleic acid, besides the physical force required, which results in cell enlargement. The growth of the whole plant is compartmentalized into areas called ‘meristem’ where cell division and cell elongation are localized. The meristem cells such as shoot apex, root apex, cambium and the intercalary zones undergo repeated mitosis resulting in replication of DNA and nuclear material and finally the cell mass increases. Adjacent to this area of meristematic activity is the region of cell elongation, which phases in to the region of differentiation and maturation.

The increase in protoplasm (occurring in cell division and elongation) is brought about through a series of events in which water, carbon - di-oxide and inorganic salts are transformed into living materials. These events include (a) photosynthesis (production of carbohydrates) (b) nutrient absorption and translocation (uptake of water, nitrogen and other mineral elements) and (3) anabolism (synthesis of various materials produced in plant from the carbon fragments produced by photosynthesis and from the inorganic nutrients and water absorbed from the soil). The energy required for all these processes is provided by a catabolic process viz., respiration (degradation of sugars and fats to release energy). The net balance of anabolism and catabolism results in growth of the plant.

The types of crops and the practices used to grow them and the sequence in which they are grown altogether refers to cropping system. It comprises of all components required for the crop production and their relationships with the environment. Traditionally the cropping systems aim at maximizing the per unit area productivity, which can be done by growing improved high yielding varieties, by adequate and scientific crop management practices and by increasing cropping intensities with the help of different cropping patterns.

In today’s world cropping system should produce more, at the same time the practices should be ecologically and environmentally sustainable. There should be efficient utilization of land and water. It should be designed to conserve soil, soil moisture and improve soil resilience.

Training and pruning of horticultural crops is very important practice to obtain a strong frame work of tree and sustained productivity. It is necessary to understand the various terms used to make the subject more comprehendible.

Crotch: It is the angle made by the scaffold limb to the trunk or the secondary branch to the scaffold limb.

Head: The point on the trunk from which first branch arises.

Leader: It is the main stem growing from ground level up to the tip dominating all other branches.

Low head trees: Trees in which scaffold branches arise within 60-70 cm height from the ground level.

High head trees: Trees in which the scaffold branch arise 120 cm above the trunk.

Scaffold branches: The main branches arising from the head are known as scaffold branches.

An orchard is the place where different kinds of fruit crops are grown in large scale. An orchard is a long-term investment and needs lot of planning and expertise. The orchard crops are generally trees, which ultimately have a large spread, so when they are planted, the distance between plants and rows is kept keeping in mind the final spread of the tree. So, before the trees attain their full growth, some suitable crops which are of short duration, like vegetables, flowers, spices and herbs are grown as intercrops.

Fruit trees are perennial, may be tropical, sub tropical and temperate types and thus require proper environmental conditions and suitable management practices for their successful growth.

Pot mixture is the media, used in the pots for propagation of nursery plants. It is the combination of different materials in a particular proportion to create better environment for rooting, growth and development of plants.

The most commonly used ingredients to make potting mixture areas follows

Plant propagation techniques refer to the methods by which the plants are multiplied and increased in number.

Methods of Propagation

i) Sexual Method of Propagation - Seeds are used as propagating material.

ii) Asexual Methods of Propagation - Plant parts, other than seeds are used for plant propagation.

Different crops are grown in a field. Any plant growing in a place where it is not desired competing with the main crops, has to be weeded out and such plants are called ‘weed’.

Effect of weed menace The weeds

Reduce crop yield and production efficiency. It competes with the main economical crop for space, water and nutrients.

Reduce crop quality.

Hamper intercultural operations.

Reduce crop quality.

Obstruct the flow of water in the irrigation channels.

Exert allelopathic effect on crops.

Harbour insect and pests, which affect the main crop of interest.

Increase the cost of production.

Water is an extremely essential component in plant growth and development. It is of utmost importance for photosynthesis, cell division, cell growth / elongation, respiration, nutrient uptake, mineral utilization and much other metabolic process, which directly affect the quantity and quality of the produce. Hence quantity and quality of water play a vital role in performance of a crop. A well distributed water supply, throughout the growth of plant is essential. Rainfall is the major source of water for the crops. Rainfall recharges the surface water resources such as rivers, streams and ponds and also the ground water resources like wells.