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Vegetables are cheaper source of carbohydrates, proteins, minerals, vitamins and dietary fibers, and hence, assume a place of very great importance in the diet of individuals. All kinds of vegetable are grown almost universally. India occupies the prime position in the production of vegetable crops and is the second largest producer of vegetables in the world. The area and production of vegetables in India have been increasing during the post-green revolution period, and the country is heading towards another revolution in the form of Golden Revolution. However, there is an utmost requirement for genetic improvement of vegetable crops in terms of productivity, qualitative characters and resistance to biotic and abiotic stresses. For any genetic improvement programme, the presence of genetic variation is pre-requisite and mutation is the ultimate source of this heritable variation.

Mutation technique that holds promise of generating a much wider desirable variability than classical breeding has been refined. Out of 2275 mutant varieties worldwide in all crops, as many as 66 mutants are in vegetables. In terms of percentage, China, India, USSR, The Netherlands, The United States of America and Japan account for 26.8, 11.5, 9.3, 7.8, 5.7 and 5.3%, respectively of mutagen varieties in all crops. Such varieties are 3% in case of vegetables. After mutation treatment by a mutagen to a specific plant, DNA alterations (deletion, duplication, inversion, translocation, or transposition of larger DNA fragments, or simple basic pair changes) occur and lead to the DNA sequence change. Hence, new characteristics of that plant are established. In fact, induced mutations supply us with many new plant lines, which may be used as primary materials for crop breeding. Hence, mutation breeding seems to be an effective and ultimate option to improve vegetable crops in the shortest possible time. A large number of new promising varieties in different crops, including vegetables, have successfully been developed worldwide using various mutagens (Chopra, 2005).

Seed sampling

Seed sampling is to draw a portion of seed from seed lot that represents the entire seed lot. Seed lot is a uniformly blended quantity of seed either in bag or in bulk.

Dietary constitution of Indian people is mostly cereal based. However, the cereals supply chiefly carbohydrates. Therefore, there is deficiency of protein, minerals and vitamins, especially vitamin A, riboflavin, vitamin C, etc. in the diet. The dieticians advocate the intake of 125 g leafy vegetables, 75 g other vegetables and 100 g root and tuber vegetables (total 300 g) everyday because vegetables provide all the nutrient components like carbohydrates, protein, fat, minerals, vitamins and water along with roughages, which are the essential constituents of a balanced diet.

India has attained food security by increased cereal production due to green revolution. In case of vegetables, although there has been increase in production from 15 million tonnes during 1950 to 94 million tonnes in 2005 but still more vegetables are needed to meet the minimum requirement of at least 250 g per day per capita. There has also been increasing demand for fresh export and for processing industries. Moreover, there is a pressure for increasing vegetable supply caused by constantly increasing population in a world of limited acres.

Addition of new agricultural land is of course not possible. In this situation, plant breeding can be expected to contribute substantially to greater vegetable productivity. This can be accomplished not only by the breeding of basically higher yielding varieties but also by the development of varieties that help to stabilize production through resistance to various biotic and abiotic stresses.

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.

Seed certification

It is a legally sanctioned system for quality control and seed multiplication and production. It involves field inspection, pre and post control tests and seed quality tests. As per Indian Seed Act seed certification is voluntary and it is not compulsory. The seed that is sold in the market is of two types certified seed or truthfully labelled seed. Whereas truthfully labelled seed is one which is being produced and marketed by the producing company by maintaining the labelling standards.

Seed Packing

Seed packaging is the process of filling, weighing and sewing of bags with seed. The choice of packaging materials and amount of seeds to be packed depends on kind of seeds to be packed, duration of storage, storage environment, the seed moisture content, the cost of seed, the cost of packaging material, the geographical area where the seeds will be stored.

Seed Processing

Seed processing may be understood to comprise all the operations after harvest that aim at maximizing seed viability, vigour and health. It includes cleaning, drying, seed treatment, packaging and storage.

Removal of seeds from dry fruits is known as threshing while that of wet fruits is known as extraction. Threshing involves beating or rubbing the plant material to detach the seed from its pod or fruit. The detached seed is then winnowed to remove chaff, straw and other light material from the seed.

Threshing / extraction methods

1. Mechanical threshing

• Various types of threshing machines with adjustable cylinder speeds are available for extraction of vegetable seeds.
• Care must be taken to avoid damage to the seed during mechanical threshing, by properly adjusting the speed of the beaters, the width of the gap between the beaters and the concave, the airflow and the sieve sizes.

Harvesting is one of the agronomic management practices that require technical knowledge on maturation of the crops. This knowledge is much important in seed production than in commercial production.

Physiological maturation

• It is the stage of accumulation of maximum dry matter within the seeds. The moisture content of the seed at this stage will be in decreasing order (25-30%) and is expressed with maximum dry weigh of seed, germination and vigour potential. The physiological maturation is represented for individual seed and this maturation will not be the same for the population, due to differential flowering habit.
• The attainment of physiological maturation is represented by sigmoid curve of growth pattern. The physiological maturation can be represented both as duration and visible symptoms.

• The seed production of varieties and hybrids should be carried out carefully by following various techniques in the region where they are well adopted.
• The various factors affecting quality seed production includes,
  1. Agro climatic factors / Ecological factors - edaphic and climatic factors
  2. Production factors
  3. Post harvesting handling of seed
  4. Seed quality control factors

The important events involved in seed development and maturation include

• Pollination
• Fertilization
• Development of the fertilized ovule by cell division
• Accumulation of reserve food material
• Loss of moisture content

Seed Production

Systemized crop production is known as seed production. In seed production adequate care is given from the purchase of seeds upto harvest adopting proper seed and crop management techniques. The benefits of seed production are

• Higher income
• Higher quality seed for next sowing

Variety is a group of plants having clear distinguished characters which when reproduced either sexually or asexually retains their characters. The genetic purity of a variety or trueness to its type deteriorates due to several factors during the production cycles. The factors that are responsible for loss of genetic purity during seed production are :

• Developmental Variation
• Mechanical Mixtures
• Mutations
• Natural Crossing
• Genetic drift
• Minor Genetic Variation
• Selective influence of Diseases
• Techniques of the Breeder
• Breakdown of male sterility
• Improper/defective seed certification System

Generation system of seed multiplication is nothing but the production of a particular class of seed from specific class of seed up to certified seed stage. The choice of a proper seed multiplication model is the key to further success of a seed programme. This basically depends upon,

• The rate of genetic deterioration
• Seed multiplication ratio
• Total seed demand (Seed replacement rate)

Seed

• In broad sense, seed is a material which is used for planting or regeneration purpose. However, scientifically, seed is a fertilized matured ovule together covered with seed coat is called seed or it is a propagating material i.e., part of agriculture, sericulture, silviculture and horticultural plants used for sowing or planting purpose.
• Seed is a mature integumented megasporangium or mature ovule consisting of embryonic plants together with store food material covered by a protective coat.
• Seeds are fertilised, mature ovules, the result of sexual reproduction in plants. Not all plants produce seed (some produce spores or reproduce vegetatively) but most of the higher plants produce seed.
• It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant.
• The formation of the seed completes the process of reproduction in plants (started with the development of flowers and pollination), with the embryo developed from the zygote and the seed coat from the integuments of the ovule.

We live in a knowledge economy, where ideas generated by talented people and the inventions they make are the new currency. Research and innovation are now seen as the key differentiating factors determining the market value of a product or service. The emphasis today has graduated from cost arbitrage and quality deliverables to Intellectual property (IP) creation and research and development. Intellectual or Intangible property is the creation of human mind. An intellectual property under protection by law is intellectual property right (IPR). Intellectual property is an important business asset giving significant competitive advantages. Intellectual properties are protected by giving time bound restriction to inventor, owner, author, originator, or plant breeder to use, sell, share, or distribute intellectual asset. These are exclusive rights to the owner and give ability for a lawsuit against others for infringement of IP owner. It is also a marketable asset, which can be licensed out to a third party bringing income to the business in the form of license payments and royalties. Intellectual property rights are legal rights, which result from intellectual activity in the industrial, scientific, literary and artistic fields. These rights give statutory expression to the moral and economic rights of creators in their creations. Intellectual property rights safeguard the creators and other producers of intellectual goods and services by granting them certain time-limited rights to control the use made of those productions. These rights also promote creativity, dissemination, application of their results and encourage fair-trading, which contributes to economic and social development.

Vegetables play an important role in human nutrition and health making them important in Indian agricultural economy. The productivity of vegetable crop is seriously affected by several biotic and abiotic stresses and makes the economic conditions of the Indian marginal farmers worst. Under Indian conditions, 25-40% of the total vegetable produce is going waste due to lack of post-harvest storage and processing facilities in the country. Conventional plant breeding methods have improved vegetable crop plants bringing together a wide array of genes responsible for novel productivity and quality traits. However, sometimes, genes needed for crop improvement are not available in the existing germplasm. In genetic engineering, individual genes affecting the traits of economic importance are introduced in commercial cultivars. It is a targeted approach to improve the crop plants, which attempts to avoid the transfer of large blocks of genetic material. It requires identification and cloning of desirable gene and its subsequent transfer in plant species for improvement. Transgenic technologies offer many scientific advantages in breeding for improved vegetable crop quality and performance. However, very few genetically engineered horticultural crops have been released to farmers. As of 2005, one thousand million acres of transgenic crops have been planted globally covering 40% of the United States land area out of which 75% of the area is devoted to cotton, 50% to corn and 85% to soybeans in the United States of America (ISAAA, 2006).

Silk is a way of life in India. Over thousands of years, it has become an inseparable part of Indian culture and tradition. No ritual is complete without silk being used as a wear in some form or the other. Sericulture and Silk Textiles Industry is one of the major sub-sectors comprising the textiles sector. Sericulture is an agro-based cottage industry. Sericulture refers to the mass-scale rearing of silk producing organisms in order to obtain silk. Sericulture is an agro-based labour intensive industry. The major activities involved in a sericulture industry are:

1. Cultivation of silkworm food plants
2. Rearing of silkworms for the production of raw silk
3. Reeling the cocoons for unwinding the silk filament and
4. Other post-cocoon processes such as twisting, dyeing, weaving, printing and finishing.

Plant tissue culture is the cultivation of plant cells, tissues, or organs on specially formulated nutrients media under the right environmental conditions. A whole plant can be regenerated from a single cell. The history of plant tissue culture has been long and started with Haberlandt in 1902 when he proposed the culture of single plant cells, his experimentation never resulted in success. White (1943) became successful in culturing plant cells for the first time, however, Morel (1960) at the Institut National Recherche Agronomique in Versailles near Paris was first to demonstrate meristem culture technology. He successfully introduced tissue culture technology to the orchid industry and produced disease-free plants of grape. By the 1970s, plant tissue culture had become a formidable technology. Plant tissue culture technique has been around for more than 30 years and considered as an important straightforward technology for the production of disease-free high quality planting material and the rapid production of many uniform plants. Its application requires a sterile workplace, nursery, greenhouse and trained manpower.

Plant tissue culturing techniques have been especially important in the agricultural community over the past many years. During this time, plant tissue culture has effectively moved from the confines of small laboratories and has taken its place among broad scale techniques employed by agricultural industry.

COMMON INSECT PESTS AND THEIR CONTROL

Since, insects are the most successful and one among the strongest rivals of man in the competition of existence. Due to their immense tendency of producing numerous viable propagules (eggs) i.e., their high fecundity, their population graph takes a sharp peak in a very short span of time.

A time reaches when the population of an insect type reaches to the level where from it starts causing inconvenience or injury to man, plants, domesticated animals and other human belongings, at such a juncture they are termed as insect pests.

Many, workers are of the view that “insects capable of causing 5 or more than 5% of damage to the crops, stored products, domesticated animals and other human dependences will be termed as pests”. Thus, if an insect causes a loss of less than 5% will not be considered as a pest. Moreover insect pests which cause a damage of 5-10% are said to be minor pests and those which cause a loss of more than 10% of yield are said to be major pests.