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Concern for improvement of nutritional quality of vegetables has arisen in the context of providing nutritional security to our ever-increasing population. Nutritional security denotes the consumption and physiological use of adequate quantities of safe and nutritious food by every member of the family and encompasses the process of equitable distribution among members of household and communities (Nandi and Bhattacharjee, 2002). This would entail the need to ensure a varied food intake, comprising all the essential macro-and micronutrients (protein, carbohydrates, minerals and vitamins), plant pigments (lycopene, beta-carotene, anthocianin, lutein, capsanthin, zeaxanthin, etc.) and other functional phytochemicals (secondary metabolites, like flavonoids, isothiocyanates, glucosinolates, etc.) through a diversified diet. In this regard, production and consumption of vegetables that are the valuable source of micronutrients, beneficial phytonutrients and highly functional phytochemicals hold the key in assuring nutritional security.

Implication of vegetables in diet has been well conceived among the high-income group in the world since human health in recent years has assumed an unprecedently important status. Increased interests in nutrition, fitness and beauty have exaggerated concerns over diet and human health. A new diet-health paradigm is evolving which places more emphasis on the positive aspects of diet. Foods have now assumed the status of functional foods, which should be capable of providing additional physiological benefits, such as preventing or delaying the onset of chronic diseases as well as meeting basic nutritional requirements so with high-income elasticity, the demand for vegetables and perception of diversified diet have been growing steadily, hence, both access and consumption of vegetables have been increasing in the urban and peri-urban population groups. However, meeting the requirements for macro- and micronutrients for most of the population groups in households and communities of South Asia, Latin America and African countries seems far off because of meager presence of vegetables in the diet. In south Asia where meat intake is low, ascorbic acid emerges as one of the most important enhancers of iron absorption. This is attributed to the fact that foods containing vegetables may provide an optimal mix of minerals, vitamins, antioxidants, dietary fibers and other non-nutrients bioactive compounds.

Plant breeding/genetic improvement aims at altering plant genotypes in a way that they suit human needs for food, feed and industrial raw products and support sustainable plant production. In that sense, plant breeding may be regarded as the evolution of plant type by the will of mankind. Plant breeding/genetic improvement is important because an improved cultivar is the most-economic and least laborious input for farmers.

Plant breeding is one of the early accomplishments of humankind. Many of the cultivated plants are the result of slow and involuntary improvement from wild progenitors by human being over centuries. In fact, the process of domestication of wild plants is one of the most fascinating chapters in the history of humankind. Concept of plant breeding came in the being through domestication as it involved selection of the most desirable types. Among the ancient domesticates, some of the vegetable crops are front-runners, like peas, radish, muskmelon, watermelon, etc. Other present day popular vegetable crops were domesticated later in the Neolithic times. Some species including certain vegetables are still undergoing the domestication process. However, for all practical purposes, the breeders have given up domestication of wild relatives of the cultivated species. Today, breeders often incorporate important characters, like resistance to biotic stresses, adaptability to environments, etc. to the cultivated forms from their wild relatives.

Selection from the available variations is the oldest and the most effective breeding procedure. However, genetic recombination at present forms the basis of modern plant breeding approach. In this respect, Josef Kolreuter’s extensive crossing experiments between 1755 and 1806 were essentially the first attempts to scientifically-reconstruct naturally occurring species and types by combining their characters. Any way, no matter what method is adopted in the breeding approach, it inevitably involves selection, which is the most difficult part of overall breeding process.

The industrial revolution in Western Europe and concomitant flourish of capitalism and increasing commercial agricultural production stimulated breeding activities as a profitable venture of capitalistic economy. Throughout the 19th century, thousands of large and small seed companies were developed in Germany, England and the United States out of this impetus.

Protein Pea, French bean, cowpea, cluster bean, amaranth and broad bean. Carbohydrates Potato, sweet potato, dry beans, yam and tapioca. Vitamin-A Carrot, palak, amaranth, pumpkin, methi and paprika Vitamin-B Garden pea and Indian bean Vitamin-C Tomato, sweet pepper, green chilli, cauliflower, knol-khol, bitter gourd, amaranth, methi, palak and cabbage. Calcium Methi, kale, beet leaf, amaranth, broccoli, onion, beet root, Indian bean, and cabbage. Potassium Sweet potato, potato, bitter gourd, raddish, dolichos, onion and green leafy vegetables. Phosphorus Garlic, garden pea, bitter gourd, broccoli, onion, leek, kale, amaranth. Iron bitter gourd, amaranth, methi, poi, beet leaf, leek and spinach

7.1. Status Vegetables are generally sensitive to environmental extremes, and thus high temperatures and limited soil moisture are the major causes of low yields as they greatly affect several physiological and biochemical processes like reduced photo-synthetic activity, altered metabolism and enzymatic activity, thermal injury to the tissues, reduced pollination and fruit set etc., which will be further magnified by climate change. The consequences of the climate change badly hit the vegetable production. Under changing climatic situations crop failures, shortage of yields, reduction in quality and increasing pest and disease problems are common and they render the vegetable cultivation unprofitable. This ultimately questions the availability of nutrient source in human diet.

2.4. Plan-wise Initiation of AICRP (Vegetable Crop) Centres in India Regular Centre Initiated in plan/year ICAR-Indian Agricultural Research Institute, New Delhi IV Plan (1971) ICAR-IARI Regional Vegetable Reseearch Station, Katrain, Kullu IV Plant (1971) ICAR-Indian Agricultural Research Institute, New Delhi IV Plan (1971) ICAR-IARI Regional Vegetable Research Station, Katrain, Kullu, Himachal Pradesh IV Plant (1971) ICAR-Indian Institute of Horticultural Research, Bangalore, Karnataka IV Plan (1971) Punjab Agriculture University, Ludhiana, Punjab IV Plan (1971) Dr. Rajendra Prasad Central Agricultural University, Pusa Bihar IV Plan (1971) Mahatma Phule Krishi Vidyapeeth, Rahuri, Maharashtra IV Plan (1971

The horticulture sector of our country is following an increased growth in area and production by 9% and 14 % respectively for the past six years (2015-21). It is reported that the growth rate of horticultural crop production accounts for 2.7% per year. Fruits and vegetables are the major sectors contributing to total horticulture production. As per the report of second advance estimates published by Horticulture statistics division, Ministry of Agriculture and Farmers Welfare during 2020-21, our country recorded the highest horticulture production during 2020-21 with an annual production of 329. 86 million tonnes from an area of 27.23 million hectares and the vegetable sector shared around 196.26 million tonnes production from 10.80 million hectare area. India is the largest producer of okra and ginger and second largest producer of potato, onion, cauliflower, brinjal, cabbage etc. Vegetables also contribute to the export market and onion, mixed vegetables, potatoes, tomato and green chilli are the main vegetables exporting from our country. It is estimated an export of worth Rs. 4969.73 crores from vegetables during the year 2020-21.

Importance of Vegetable Seed Production

Though we are leading in many of the vegetables in area and production, our national average in productivity of the major vegetables is far less compared to the world average. The country s estimated vegetable production by the year 2050 is 375 million tonnes from 15 million hectare with an average productivity of 25 t/ha. Low productivity is mainly because the farmers are still relying on old varieties which are less yielding and susceptible to pest and disease. Unavailability of the quality seeds of newly released varieties is one of the main reasons for this production gap. A substantial increase in yield and quality of vegetable crops can be achieved by adopting suitable agronomic practices, plant protection measures and use of quality seed. Now a days, there is an increased demand for good quality seeds of open pollinated varieties as well as hybrid seeds through which an increased vegetable production can be achieved for meeting the requirement of increasing population. So far, very limited number of vegetable hybrids have been developed and released by public sectors and majority of the existing promising hybrids in vegetables are from private sectors.

I. FILL UPS

1. _____ is the method of propagating plants with the use of organs other than the seed and spore.
2. The word asexual, which means _____.
3. In asexual, the _____ of the male and female sexual gametes (fertilization) is not a requisite to the production of new plants.
4. In vegetative propagation, the union of the male and _____ sexual gametes (fertilization) is not a requisite.
5. _____ without fertilization is known as vegetative propagation.
6. In vegetative propagation, _____ cell division takes place.

1. VEGETATIVE PROPAGULE

Vegetative propagation or asexual propagation is the method of propagating plants with the use of organs other than the seed and spore. In contrast to sexual propagation, the union of the male and female sexual gametes (fertilization) is not a requisite to the production of new plants. Hence the word “asexual”, which means “without sex” or “not sexual”.

4.1. Promotion of Kitchen Gardening 4.1.1. Essential Guide Lines for Kitchen Gardening • The location should be in the backyard of the house. As far as practicable, kitchen garden plot should be located near to the well, water tap or other source of irrigation. It should never be located in the shady area of home, which is generally not suitable for most of the vegetables. There should be enough of sunlight for major part of day. • It should be fenced with boundary wall or fruit crop or live fence all around. • The layout should be such as to make the garden look attractive and allow access to all its parts. The land should be laid out in small paths and plots. • The garden should preferably be rectangular in shape. • About 200 m2 area is sufficient for a five members family to supply about 1.5 kg vegetable per day

Plant viruses, like all other viruses, are obligate intracellular parasites that do not have the molecular machinery to replicate without the host. The plant viruses are defined as viruses pathogenic to higher plants. The discovery of plant viruses causing disease is accredited to Beijerinck who determined in 1898 that the plant sap obtained from tobacco leaves with the mosaic disease remained infectious even after passing through a filter. This was in contrast to bacteria, which were retained by the filter. Beijerinck referred to the infectious filtrate as a contagium vivum fluidum, thus, he used modern term virus.

Viruses occasionally cause significant problems in vegetable crops. However, the prevalence and severity of viral diseases differ from year to year. Aphids spread many of the viral diseases observed in vegetables. There are two types of viral transmission by aphids, i.e., persistent and non-persistent transmission. It is important to understand the difference between these two because persistent and non-persistent viruses differ both in their uptake and behaviour within the insect vector, consiquently, tactics used to limit their and spread vary considerably. In persistent transmission, the aphid usually carries the virus for life. Uptake of virus requires extended feeding and after an incubation period of several hours or days, the virus replicates and circulates within the insect. Because of the time required for feeding before acquisition by an insect vector, the spread of persistent virus is favoured by colonizing aphid species that spend time in the crop. Controlling the aphid vectors with insecticides can reduce the spread of persistent plant virus significantly. In contrast, aphids can acquire non-persistent viruses (NPV) within a few seconds after sampling an infected plant. Winged migratory aphids can move quickly from infected plants onto healthy ones, transmitting the virus in the process. Aphids rapidly lose the virus particles from their mouthparts, which are cleaned when they feed on the next available plant and are unable to transmit disease to additional plants. Because of the speed in which aphids acquire and transmit non-persistent viruses, insecticides are not usually effective in controlling their spread. One of the most common viruses found in many vegetable crops is cucumber mosaic virus (CMV). This is transmitted by several aphid species in a non-persistent manner. There are several strains of CMV that can infect over 775 different plant species in 85 families including snap bean, peppers, tomato, lettuce, tobacco and sugar beets. Symptoms vary depending upon the plant species infected but range may be from yellow-green mottling on leaves and fruits to severe stunting of plants. The viral diseases affecting different vegetable crops are being discussed below:

Visit to a seed processing unit and attending the following questionnaire to know firsthand information on operations of shop floor

NAME OF THE UNIT: 

    1.    Location of Seed Storage 
    2.    Date of Inspections/visit

India is a major exporter of vegetables with 10th position in the world. In the past, the Dexport of Indian vegetables was restricted to potatoes and fresh onions, however, now, the Government of India finds great opportunities for expanding exports of several vegetables including lettuce, fresh peppers, tomatoes, squashes, gherkins, etc. Under World Trade Organization (WTO) regime, the development of stronger seed industry and improved production technology will give India a competitive edge in global market. New opportunities and challenges are emerging every day in the dynamic and global vegetable-based industries. However, such opportunities can be harnessed only if assured quality, in terms of organic farming and reduced pesticide residues, is maintained (Shanmugasundaram, 2004).

Most of us consider weeds to be the troublesome, competitive, aggressive, undesirable, unsightly elements of the plant world. We hate weeds since desirable plants cultivated by us are deprived of food, water, sunlight and space by these plants. They can easily colonize an area and thrive even under non-ideal conditions of growth and may affect human welfare adversely. It is perhaps due to this that the saying, when weeds win all the people lose, has come into existence.

The terminology committee of the Weed Society of America gives the simple definition of weed as a plant growing where it is not desired. King (1974) in his book Weeds of the World observed that ‘‘a plant classed as a weed in one region where it has few, if any, uses may when growing in another region, possess some very valuable uses, or in few cases may actually be cultivated’’. For instance, Bermuda grass (Cynodon dactylon) is a highly troublesome weed in crop fields, but in village pastures, it is a much sought for forage grass. Quack grass (Agropyron repens) is a very good soil binding grass on erodable non-crop lands but it is a serious weed when it infests crop fields and orchards. Campbell (1923) considered weeds as ‘honest, independent competitors for food materials in the struggle for existence’. He pointed out that the term, weed has developed in the minds of people not according to specific qualities or by a definite concept in the mind of man, but by human caprice, e.g., corn is a cultivated crop, hence, desirable plant in a corn field. However, if a corn plant grows in a Soya bean field, it is considered a weed by the Soyabean farmer. Sometimes, two persons may differ about the weedy nature of a plant at the same place and time, e.g., water hyacinth (Eichhornia crassipes) is a weed for fisherman but it is a plant of aesthetic value for a city dweller.

Thus, a corollary to the above definitions of weed is that weeds are those plants, which grow out of their place, interfere with the utilization of natural resources, prolific, persistent, resistant, competitive, harmful and even poisonous in nature and can grow under adverse conditions.

Onion is highly vulnerable to weed competition because of its slow early growth, shallow roots, narrow upright leaves and limited canopy development. Weeds compete for light, water, nutrients and space while also harbouring pests and pathogens. Severe infestation during the critical competition period can cause substantial yield reduction. This chapter describes major onion weeds and evaluates cultural, physical, mechanical, biological and chemical control methods. Timely planting, suitable spacing, mulching, raised beds, manual weeding, mechanical tools, herbicides and biological agents are discussed. Integrated Weed Management is recommended as a smart approach combining complementary methods to improve weed control, protect soil health and sustain onion productivity.

I. FILL UPS

1. Green revolution in wheat was started by _____ in Mexico.
2. Wheat revolution in India was started by_____.
3. Isolation distance for wheat seed production is _____.
4. Seed rate for wheat seed production is _____.
5. Wheat is a _____ pollinated crop
6. Seed multiplication ratio for wheat is ranged from _____.
7. Spacing adopted in wheat seed production plot is _____.
8. Average seed yield in wheat is _____.
9. _____ is the critical moisture content for wheat seed storage
10. The minimum pure seed percentage for wheat foundation seed is _____.