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Tomato is relatively recent addition to the world’s vegetable crops. Now became one of the most important vegetable crops and is popular & widely consumed. It is being grown extensively in USA, China, India, France, Israel and Netherland.
 
It is used in fresh and processed form. Among the vegetables maximum attempts have been made to improve this crop because of its short duration, easy cultivation and large number of seeds per fruit and this has made it an ideal crop for many research works. An exclusive Tomato Genetics Co-operative located in University of California, USA, published genetic information on the crop and maintains a large number of     collections which have already been thoroughly catalogued.
 
Origin and Distribution: Native of Peru in South America and spread to North America by migrating birds. Largest number of wild tomato forms is present in Mexico. Spanish Priests introduced it to Europe in around 1550. In Europe it is known as Poma amoris = Amorous apple (Love apple). Wild relatives found in narrow elongated mountainous regions of Andes in Peru, Ecuador and Bolivia and Galapagos islands. Domestication and cultivation of tomato appears to have first occurred outside its centre or origin. Domestication of tomato was first done by Mexican people i.e. Red Indians, which is considered as secondary center of origin. Now cultivated tomato is common in Peru but recently added to their diet.

India is the primary centre of origin of brinjal. Decandolle (1904) reported it as native of Asia. In Europe it is not known earlier (before 17th early). According to N.I Vavilov, the egg plant originated in Indo–Burma region and china and spread to South Europe, china and Japan. Vavilov (1951) suggested China a centre of origin of brinjal. Crop is restricted mainly to South and South-East Asia, Southern Europe, China and Japan. Wild brinjal types are available in Southern Coastal area of Africa.

Botany

Solanum melongena’ L. var. esculentum - round or egg shape 
var. serpentinum – long, slender type 
var. depressum – dwarf brinjal plant 
It is often cross pollinated crop due to heteromorphic flower structure (heterostyle)

‘Chili’ (European literature) word derived from ‘Chile’ which means any pepper in Mexico and Central America. Peppers are an important constituent of many foods adding flavor, colour, vit.C and pungency and therefore indispensable to the world food industries. China, Mexico, Japan, Turkey, Indonesia, Pakistan and India are major producers.
 
Origin:  The cultivated chilli is of South American origin. Authorities generally agreed that capsicum originated in the new world (America) tropics and sub tropics. Pepper pods are there from 2000 year old burials in Peru. Decandolle concluded no capsicum was indigenous to the old world (Europe), peppers unknown in Europe until 16th century. Chilli was introduced into Spain by Columbus on his return trip in 1493 and cultivation spread from Mediterranean region to England by 1548 and to central Europe by close of 16th century. Portuguese carried capsicum from Brazil to India prior to 1885 and cultivation was reported in china during late 1700’s.

All capsicum species have 2n = 24. Polyploids with 2n = 36, 48 and  aneuploid 2n = 25 reported

If there is scarcity of food, potato can come to the rescue because of its virtue of high yielding (40-50 t/ha) and is a staple food. It produces more calories per unit area and per unit time than any other major food crops. Potato which is the staple food of Europeans and Americans belong to the highlands of Andean mountainous regions of Peru and Bolivia where it has been cultivated since 6000 years.
 
Origin: Peru, Bolivia. Many wild species occur at Mexico and Central America. Potato was introduced to Europe in 16th century by Spaniards (Salaman, 1966) and in early 17th century to India most probably by Portuguese. There are some suggestions based on linguistic and botanical evidences that potato might have been introduced in India directly from South America across the Pacific Ocean. Earlier potatoes were grown in hilly areas of North and South since British settlers brought the varieties continuously from UK and these were bred for long day temperate conditions of Europe. But in India potatoes are grown in short day-subtropical plains. The seed stocks used to degenerate due to accumulation of viruses and loose their yield potentiality. Seed potatoes were mainly imported from Europe i.e. U.K., Italy and Netherlands and Burma till the beginning of Second World War and the imports gradually reduced.

Okra has higher average nutritive value (ANV) of 3.21 which is higher than tomato, egg plant and most of the cucurbits except bitter gourd (Grubban, 1977). Its roasted seeds are substitute for coffee. It is one of the export potential crop where it accounts to 60 per cent of fresh vegetables (excluding potato, onion and garlic) exported from India. Importing countries are Middle East, Western Europe and USA.

Origin and Distribution : It belongs to the genus Abelmoschus established by Medikus, 1787, however de Candolle (1824), treated it as section of Hibiscus.   In 1924 Hochreuntiner reinstated the genus Abelmoschus of Medikus stating that calyx, corolla and stamen fused together at the base and fall as one piece after anthesis (deciduous) where as in case of hibiscus these are persistent. Though the genus is of Asiatic origin, the origin of cultigen Abelmoschus  esculentus is variable like India (Master, 1875) Ethiopia {de Candolle (1883) and Vavilov (1957)}, Western Africa (Chevalier, 1940 and Mardorct, 1947) and Tropical Asia (Grubban, 1997) and probably its might have entered India at the end of 19th century. Cultivated okra is of old world origin. It arose as a cultigen in the Abyssinian region (Ethiopia). Wild species are indigenous to Africa.  Three wild species Abelmoschus tuberculatus, A. moschatus and A. ficulneus are native to India. Introduced to Mediterranean region to Europe and Asia. But during Columbian period it was introduced to America.  It still turnout to be polyphyletic (many places) in origin. A. tuberculatus (Indian origin) and an unknown species cross resulted into A. esculentus.

Cucumber

Cucumber (Cucumis sativus) is a warm season vegetable used as salad and for pickling purpose has little or no frost tolerance.  Growth and development favoured  by temperature above 200C.  Cucumber cultivars generally classified as pickling or slicing types. In India often cucumbers (Cucumis sativus) are confused with melons (Cucumis melo ) as morphologically some variants of these species overlap, but they are not cross compatible. Kakri of North India are different from kakri of South India and Maharashtra. In Maharastra and South India cucumbers are referred as kakri but, in North India Kakri means Long melon i.e. Cucumis melo Var. utilissima.

Melons (Cucumis melo) are annuals with climbing, creeping or trailing vines of length up to three meters. The desert types quench thirst and add to the nutrient content of main diet. The non-desert types are used as vegetables. Muskmelon (Cucumis melo., 2n=2x=24) encompasses the netted, salmon -flesh cantaloupe, the smooth – skinned green fleshed ‘Honey Dew’, the wrinkled, white – fleshed, ‘Golden Beauty’ and several other dessert melons in USA.

Origin: Not known with certainty but, 40 or more wild species of Cucumis are found to occur in the tropics and subtropics of Africa. Wild species of Cucumis occur in Africa and it is likely that it originated in African continent. It does not appear to have been known to the ancient Egyptians, not to the Greeks and seemed to have reached Europe towards the decline of Roman Empire. Although melon was introduced into Asia at a comparatively later date there are undoubtedly well developed secondary centers of origin of C. melo in India, China and then Southern USSR. In India Oriental pickling melon (C. melo var conomon) and snap melon (C. melo var momordica) are unique and have considerable variability in Western Ghats of India. They are popular desert and preserving melons cultivated in Warm humid tropical condition of South India. It is also considered that China as primary center of origin and Indo-Burma as secondary center of origin. It has been introduced to Europe and from Europe to the USA by the early travelers. At present muskmelon is being cultivated throughout the world under tropical and subtropical climatic conditions. Polymorphism in leaf, flower, fruit shape and colour (Kirkbride, 1993), allowed the classification of horticulturally important melons into seven groups.

Water melon is tender to frost and most of cultivars require relatively long growing season. Plant growth and fruit development are fallowed by higher temperature and abundant sunlight. Atmospheric humidity greatly regulates fruit and foliage diseases.

Taxonomy and Origin: Ealier it was classified as Citrullus Vulgaris Schrod. But in 1963 Thieret called attention to the correct name, C. lanatus (Thumb) Mansf. Africa is centre of origin of the genus. In 1857 David Living Stone, the famous missionary explorer found both bitter and sweet melons grown together in Africa and native people used them as source of water. Cultivation is prehistoric as there are pictures made in ancient Egypt. Early cultivation occurred in Mediterranean area and as far as India also and It was brought to USA by European colonist as early as 1629.

Ridge gourd or Ribbed gourd (Luffa acutangula Rox b. L) and Sponge gourd or Smooth gourd (Luffa cylindrica) have diploid chromosome number  2n=2x=26. Luffa has old world origin in Subtropical Asian region including India (Kalloo, 1993). These two species are inter-crossable. F1 plants generally, intermediate between the parents and showed various irregularities like, univalants, rings and chains of 4 chromosomes, chromatids bridges and fragments at metaphase and thus the species are not easily crossable and the F1 plants appear to be of not much practical value. The genus is monoecious annual vine, tendrils are branched, flowers are yellow, anthers are free and pistil has three placentas with many ovules and stigma are three and bilobate. Fruits oblong or cylindrical and rind becomes dry on maturity.

It is rich in iron and Vit –C and native of tropical Asia particularly eastern India and Southern China (Sheshadri 1986 Mini Raja et al., 1993).
 
Botany: Monoecious annual, staminate flowers small, yellow and borne on slender pedicel. Pistillate flowers solitary have small pedicel, flowers are yellow, leaves segmented pentamerous. Filaments 3, two are bilocular and one is unilocular. There are three short styles ended with three bilobed or divided stigmas.

Chromosome 2n=22: 6-centromere in middle, 3-submedian, 2-subterminal  (Vargheuse, 1973) 

Momordica dioica: 2n=28

Momordica cochincniensis: Sweet gourd of Assam

Germplasm

KAU-Vellanikara, IIHR-Bangalore, NDUAT-Faizabad, CSAUAT-VRS, Kalyanpur, BPUA&T-Pantnagar and IARI- New Delhi are the major sources of bitter gourd germplasm.

Bottle gourd (Lageneria siceraria) 2n=2x=22 is also known as white flowered gourd. Most important vegetable of ancient China.
 
Origin : According to De Candolle (1882) Bottle gourd has been found in wild form in South Africa and India. However, Cutler and Whitaker (1962) are of the view that probably it is indigenous to Tropical Africa on the basis of variability in seeds and fruits. This species appear to have been domesticated independently in Asia, Africa and the New world (Heiser, 1973).
 
Botany: It is monoecious, annual vine with soft pubescence. Leaves are cordate ovate to reniform-ovate, Flowers are white, solitary, open at night and has hairy ovary. Fruit shape is cylindrical, oval egg shaped, club shaped, round and other shapes also appeared.

Genetics of Important Traits

Bitterness: Single dominant gene (Path and Singh, 1950)

Fruit colour: Monogenically controlled (Kalloo, 1993)

Two major genes are involved for fruit shape (Path and Singh, 1950). Single gene for fruit colour involved (patchy v/s white) and reported by Path and Singh (1950). Monogenic recessive inheritance for andromonoecious sex form is reported by Singh et al. (1996). Hermaphrodite sex form is characterized by long corolla (3.5-4.5cm instead of 2.5-3.5cm in normal). In hermaphrodite condition fruits bears prominent blossom scar.  Long fruit conditioned by AA genotype and Round fruit is due to aa genotype where Partial dominance is reported (Kushwaha, 1996).

Squashes and Pumpkin (Cucurbita, spp, 2n = 2x = 40) are the words quite often used interchangeably. However, the term squash is more commonly used for C. pepo which is consumed as an immature fruit. The term pumpkin is normally applied to the edible fruit of any species of Cucurbita utilized when ripe as a table vegetable or in pies.
 
Origin:  The genus Cucurbita is native to America.  The center of diversity is the tropics near the Mexico- Gauatamla border. The archaeology evidences indicate that these were widely cultivated in South Western United States, Mexico, and northern South America in Pre-Colombian times i.e. prior to 1492 A.D.

C. pepo : Summer squash : Some varieties belong to winter squash, pumpkin and marrows. It has bushy habit, peduncle hard, sharply angular, grooved, leaves broad, triangular in outline, usually with deep lobes little or no expansion of peduncle at fruit attachment. In North America it is commonly found.

C. mixta : Squash, cymlins, cushaws: It is used as summer and winter squash, leaves shallowly lobed, hard corky peduncle. This is also commonly found in North America.

Keys to Genera
Flowers zygomorphic, stamens definite, corolla papillonacious, petals imbricate: 1I, 1O, 3 IO
Group I:    Herbs or shrubs, leaves imparipinnate, leaf lets entire, pods usually dehiscent, or if indehiscent usually small, a few seeded. Cyamopsis
Group II:    Herbs low or climbing, leaves paripinnate, leaflets ending in a tendril or bristle, style bearded, pods dehiscent.
Sub group 1: Staminal tube oblique at mouth, pod compressed. Vicia
Sub group 2: Staminal tube truncate (cutting off) at mouth, pods torpid.  Pisum
Group III:     Climbing or prostrate and rarely erect
Sub group 1: style bearded, stamen diadelphous
Sub-sub group: stigma terminal: Dolichos
Sub-sub group: Stigma oblique: Keel spiral : Phaseolus
Keel not spiral: Vigna
Sub group 2: Style not bearded, stamen monodelphous: Canavalia
Group IV:    Trees or shrubs, some times climbing, pods indehiscent: Psophocarpus

Garden Pea
It is cool season crop cultivated throughout the world. It is extensively grown in temperate zone and is restricted to cooler altitudes in tropics and winter season in sub tropics. It is rich source of proteins (25.6%), amino acids and sugars. It goes well with other vegetables in vegetable dish.

Among beans, the most popular bean is French bean and it has wider distribution and larger gene pool. Various names are associated with cultivars viz., Snap bean, salad bean and green bean and all these names associated are with beans of vegetable types. The names haricot bean, dry bean and navy bean are applicable to pulse types. String bean, dwarf bean and pole bean applicable to growth forms. It is known as Rajmah in Hindi, Tingalawari in Kannada and Fras bean in Punjabi. Cultivars preferred for Canning, frozen and freeze-dried are having round pods. Fresh market cultivars are flat or oval shaped. Yellow pod cultivars are also grown. Generally fresh market cultivar yields higher in temperate region than in tropical region. Beans are said to be antidiabetic and good for bladder burns, cardiac, carminative, diuretic.

Origin and Distribution: Phaseolus vulgaris was domesticated in Central America about 7000 years ago and it is also thought to be domesticated in Brazil and Northern Islands and was introduced to Europe in 16th century. Vavilov (1951) reported that Phaseolus vulgaris originated in South Mexico and Central American centre of origin. The first cultivar has been selected in Peru. From Peru it spread to Europe and to Asia. Wild species P. aboriginus in North West Argentina is considered as the wild progenitor of French bean. Based on growth habit, crop can be classified into pole type, semi pole type and bush type. Former varieties are more string types. American origin of P. vulgaris is questioned by De Candolle (1584). Southern part of Mexico and Central America are considered to be primary centre of origin. While secondary centre lies in Peru-Bolivian-Ecuador of South American continent. In Europe, French bean spread rapidly in 16th and 17th centuries and reached England by 1594. From Europe, it was introduced to India during 17th century (Simmonds, 1976).

Southern pea / black eyed pea are the other names associate with cowpea. It is grown for vegetable and also as pulse crop and varieties are specific for use.

Classification of Cowpea
1.    Vigna unguiculata (L.) Walp. Cv. Sesquipedalis: yard long bean or asparagus bean: Possess long pods and used as vegetable. 
2.    Vigna unguiculata (L.) Walp. Cv. Cylindrica: dual purpose, i.e. vegetable and pulse 
3.    Vigna unguiculata (L.) Walp cv. Radiata: Pulse type.
 
More emphasis is given for pulse types for crop improvement. Less attention is given to vegetable types. Pole and bush types are available in vegetable type. Cowpea improvement is from vine to bushy habit with low fiber content and low glucosides and increased protein content.
Origin and Distribution: Cowpea is in cultivation from ancient times in the tropics of old world. Country of origin is uncertain. In India, it has been known from the vedic times. Vavilov (1939) considered India as the primary centre of origin. But it is now generally agreed that Africa is centre of origin since wild forms are found in Africa and in Asia wild forms are absent (Smartt, 1990). Faris (1965) concluded that, cowpea arose from domestication of wild form Vigna unguiculata ssp dekindtiana in West Africa. But domestication is actually happened in Ethiopia and dissemination was West wards Africa, East ward across the Indian Ocean. It has spread from Africa to Asia and Europe through Egypt. Introduced to West Indies in 16th century by Spaniards and was taken to USA around 1700. Now cowpea is widely distributed throughout the tropics and subtropics.

Dolichos bean is known as Lablab bean, hyacinth bean or sem. Grown as field crop in MP, Maharashtra, AP and TN. Genus Dolichus is renamed as Lablab (Syn. D. lablab, D. purpureus, Lablab niger, L. bvulgaris) and Lablab purpureus name is widely accepted. Dolichos lablab L. (synonyms Lablab purpureus (L.) Sweet.) is leguminous pod vegetable grown in tropics and few temperate countries. Lablab niger var. lablab is synonym to Dolichos lablab var. typicus where long axis of seed is parallel to suture and is vegetable type. Lablab niger var. lignosus synonym to Dolichos lablab var. lignosus where long axis of seed is perpendicular to suture and is pulse type.

Onion

Onion is very popular vegetable crop grown worldwide. Consumption is in the form of fresh, frozen, and dehydrated bulbs and green bunching onion. Origin of Allium cepa is still somewhat mystery. Vavilov (1951) suggested that the onion originated in the area of Pakistan. Others have suggested Pakistan, Iran & the mountain areas to the north (Jone& Mann, 1963). One fact is certain that the onion has been around in its present edible form for thousands of years. Onion recorded in tombs as early as 3200 B.C. It was mentioned as a food in the bible and in the Koran with reference thought to be around 1500 B.C. In addition to being a food considered by people, plant is having certain healing power. Some early drawing indicates that onions were used in spiritual offerings.

Cabbage

Cabbage is an important crop in USA, Northern European countries, Russia, Japan & Australia and its breeding occurs here, but Holland and Japan are the major breeding countries. It is also being cultivated in India and crop improvement work is taken up in India also.

Origin and General Botany: Historical evidence indicates that modern hard head cabbage cultivars descended from wild non headed Brassica originated in the Eastern Mediterranean and in Asia Minor. The Celts and Late Romans are responsible for spread cabbage throughout Europe. Latin name Brassica derived from Celtic word “bresic” meaning cabbage. Over a period hard headed evolved in Northern Europe and loose headed and heat resistant types evolved in South Europe. Cabbage was first introduced to America in 1541 by French explorer Jacques Cartier (planted seeds in Canada) and earlier colonist introduced the crop in to India also. Round headed types-are evolved earlier than flat (evolved in 17th or 18th century).  Broccoli, Cauliflower, Brussels Sprout, Collards, Kale, and Kohlrabi are all readily intercrossed members of this species.

Cauliflower follows cabbage in importance with regard to area and production in the world. However in India Cauliflower is more widely grown than cabbage. This crop grows at a latitude 11°N to 60°N with average temperature ranging from 5- 8°C to 25-28°C. It can stand to the temperature as low as -10°C and as high as 40°C for a few days. Italy and India are the major countries growing CF on large scale. Important cauliflower growing states in India are UP, Karnataka, West Bengal, Punjab and Bihar. It is commonly grown in Northern Himalayas and Niligiri hills in south.

Origin and Distribution: Cauliflower is thought to have been domesticated in the Mediterranean region since, the greater range of variability in the wild types of B.oleracea is found there (Nieuwhof, 1969). Wild Cole warts are still found in wild state in sea cost of England and Denmark and in the North West France and various localities from Greece to Great Britain. The Cole crops, including cauliflower and cabbage have descended from a common Kale like ancestor, the wild cabbage (B.olearcea var. sylvestris L.) which is still found in western and southern Europe and North Africa (i.e, sea coasts of England and Denmark and in North West France and various localities from Greece to Great Britain). Cyprus and area around Mediterranean courts are considered to be the primary centers of origin for Cauliflower. It is also reported that cauliflower is originated from a related species. B.cretica. As per Bosewell (1949), it originated in the islands of Cyprus from where it moved to other areas like Syria, Turkey, Egypt, Italy, Spain and North Western Europe. Cornish types originated in England fallowed by temperate types originated in Germany and Netherlands in 18th century. The present Indian tropical cauliflowers developed as a result of intercrossing between European and Cornish type. In India tropical types with resistance to high temp and high rainfall conditions have been developed. Tropical types are grown in Indian plains from May to September, followed by temperate types known as snowball cauliflower.

Amaranthus is one of the main genera of large and taxonomically diverse group of leafy vegetables. Amaranthus is the cheapest dark green leafy vegetable because of low production costs and high yield. It is often described as poor man’s vegetable.

Origin and Distribution: The main vegetable type Amaranthus tricolor L. originated in South or South East Asia, particularly in India. Budhist monks and Muslim invaders took the crop to neighboring countries. Another vegetable type A. dubius shows diversity in Central America, Indonesia, India and in Africa. A lividus is a popular leafy vegetable in Southern and Central Europe. Amaranthus included 50 to 60 species.

Carrot (Daucus carota L.) is a cool season root vegetable and temperature is the important factor affecting root shape and colour, besides soil type and moisture content of soil. It provides an excellent source of vitamin A and fiber in the diet. The genus Daucus, which include carrot, has many wild forms that grow mostly in the Mediterranean region and South West Asia. Representatives are found in Africa, Australia, & North America. For Daucus carrot L. it is generally agreed that Afghanistan is the primary center of genetic diversity and therefore the primary source for dissemination. Asia Minor, Afghanistan, North West India, Iran and Turkey are the centers of origin of carrot. Banga (1957& 1963) has provided evidence that the purple (anthocyanin) carrot together with a yellow variant spread from Afghanistan to Mediterranean area as early as 10th and 11th century. It is known in Western Europe in 14th and 15th century, China in 14th century and Japan in 17th century. The European carrot (Carotene carrot) derived from the Asiatic (anthocyonin containing) form of carrot (tropical carrot).  Afghanistan is the centre of diversity of the purple coloured carrot (anthocyanin). Integration of Asiatic and European carrots has given the present day forms. The yellow coloured (carotene rich) forms were also thought as mutants of anthocyanin carrots. The yellow mutants were traced in Asia Minor in 10 and 11th centuries, Spain in 12th century, North Western Europe in 14th century and England by 15th century.  The crop was introduced to China during 14th century and to Japan during 17th century. D. carota and D. sativus are only cultivated species of the genera with Chromosome No. 2n = 18. All forms have same chromosome number. 

It is a popular root crop having wide range of adaptability, grown in Japan, Koria, China, India and other European countries.

Origin and Distribution: Radish was an important food in Egypt during 2000 BC.  Fossils study reveals that, it was a food as early as 2700 BC. It spread to China during 500 BC and to Japan during AD 700. Variability of crop decreased from Europe to China and from there to Japan. Recent study indicates that East of Mediterranean, most probably China was the centre of origin of the crop. This means Europe and Asia are the probable places of origin.

Beta vulgaris 2n = 2x=18 is an important vegetable crop in Eastern and Central Europe and it belongs to family Chenopodiaceae. It is of lesser importance in Western Europe and USA where it is known as garden beet. The swollen roots are consumed as vegetable and salad. The other types which are non-horticultural forms are known as sugar beet, mangold and fodder beet.
Origin: Leaf beet is the earliest domesticated form. It is believed to be originated from Beta maritima known as sea beet which is indigenous to Southern Europe. 
Botany: Biennial producing enlarged hypocotyl (roots) and rossette of leaves in first year and flowers and seeds in second year.

Turnip is the root vegetable cultivated in cooler season or temperate regions of the globe. Brassica rapa L 2n = 2x = 20 is formerly known as B. campastris subsp rapifera. Swede (B. napus var. napobrassica) is directly related to turnip.
Origin: It is originated in cooler part of Europe, presumably from biennial oilseed forms. It was known to Greeks and Romans at beginning of Christian era. It was introduced to Britain from France by Romans and into North America by the early European settlers in the 17th century.

Sweet potato Ipomea batatas(L). Lam. is an asexually propagated vegetable. It is grown in most of the tropical and subtropical region of the earth. In USA production extended to temperate regions. Vines as well as roots are eaten or fed to live stock. It is the source of industrial starch and potential source of the alcohol. Among the major tuber crops cultivated in India sweet potato rank third after potato and cassava in area and production.

Origin: Available evidence suggests South Mexico through Central America and Northern South America as the probable center of origin. It is perennial but handled as annual. Its hardiness and drought tolerance are well recognized.

Family: Convolvulaceae, Chromosome number: 2n=90

It is the only known natural hexaploid morning glory. Most of the wild species are diploid (2n=30). Hybridization is restricted with in species because of its hexaploidy nature. Extensive variability with in species is observed. Tuber is the fleshy subterranean stem or shoot but in sweet potato tuber is a root, and hence it cannot be a tuber (common error). It is a perennial, and the storage root is capable of continued enlargement and does not mature in the sense of reaching some final size or stage of development. From the stand point of function, the root system consists of absorbing roots and fleshy storage roots.

Cassava (Syn: Tapioca) Manihot esculenta (Crantz) (2n = 2x = 36) (Hindi : Mravuli) is perennial shrub cultivated in tropics for its starchy tuberous roots. It is one of important tuber crops cultivated in tropics because of its high carbohydrate yield per unit land and labour and its adaptation to poor soil and water stress and its tolerance to dominant pest and diseases. Cassava contains cyanide, the toxic principle which limits food and feed value. In cassava the glycoside linamarin and lotaustralin are converted to hydrocyanic acid, a potent toxin, when come in contact with linamerase, an enzyme that is released from rupture of cells. Tuber peel contain significantly higher amount of glycosides than the pulp. It can be removed by cooking in water for about 5 minutes.

The term ‘Horticulture’ is derived from two Latin words, Hortus meaning Garden and Cultura meaning Cultivation. In ancient days the gardens had protected enclosures with high walls or similar structures surrounding the houses. The enclosed places were used to grow fruits, vegetables, flowers and ornamental plants. Horticulture differs from agriculture and forestry in specializing the cultivation of garden crops. The garden crops include fruits, vegetables, flowers, ornamental trees, spices, plantations, medicinal and aromatic plants. Horticultural crops do not give food grains. The products of horticultural crops such as fruits and vegetables are highly perishable so that they are utilized in the fresh state. In general horticultural crops need more intensive cultivation (i.e. need more work) than the agricultural crops.

Special Features of Horticulture

As horticultural crops generally need intensive cultivation, they require a large input, capital, labour and technology per unit area of land.

Many cultural operations are specific to horticultural crops. The cultural operations such as propagation, fertilization, training, pruning, harvesting and marketing are skilled operations and these are specific to horticultural crops.

Mostly the horticultural products are utilized in the fresh state and are highly perishable.

Most of the horticultural crops are the rich sources of vitamins and minerals.

Gratification or aesthetic sense is an exclusive phenomenon for horticultural science.

Horticulture means the cultivation of garden plants. The garden plants are comprised of fruits, vegetables, ornamentals etc. The culture covers the operation from raising and planting of saplings to the ultimate use of the products and, as such, it is the most intensive of all the agricultural sciences. However, the concept of growing plants in garden or in an enclosure does not fit well in the changed perspective where large scale cultivation of fruits, vegetables and flowers extending over several square kilometers, in many a place nowadays, delimits the boundary of garden.

Importance of Horticulture

The importances of horticulture are established not only as a source of nutritious foods but also in many other ways which are narrated in the following points:

Social- Due to the long association, the fruits are seen to have a permanent seat in the social life of man. As a consequence, various fruits have acquired their place in art, music, literature, customs and habits of various nations of the world. The description of fruit as symbolic insertion in the poems and literatures, the use of whole fruit plant or part thereof in various social festive and public gathering, and conferring titles to individuals in the name of fruits or naming a region or whole district after the name of a fruit are nothing but an indication of their popularities and social position in various countries.

Fruits and vegetables play an important role in balanced diet. These provide not only energy rich food but also provide vital protective nutrients/elements and vitamins. Comparatively fruits and vegetables are the cheapest source of natural nutritive foods. Since most of Indians are vegetarians, the incorporation of horticulture produce in daily diet is essential for good health. Realizing the worth of fruits and vegetables in human health, Indian Council of Medical Research (ICMR) recommended the use of 120g fruits and 300g vegetables per capita per day. With the growing awareness and inclination towards vegetarianism worldwide the horticulture crops are gaining tremendous importance.

Functions of fruits and vegetables in human body

Fruits and vegetables provide palatability/taste.

Improves appetite and provides fiber to overcome constipation.

They neutralize the acids produced during digestion of proteins and fatty acids.

They improve the general immunity of human body against diseases, deficiencies etc.

They are the important source of vitamins and minerals for used in several bio-chemical reactions occur in body.

Classification is system of placing an individual or a member in various groups or to categories them according to particular plan or sequence which is in conformity with the nomenclature. From time-to-time for purposes of convenience plants or fruits have been classified in various ways that makes possible to refer them to a large number of kinds under a group name without enumerating or specifying individually. The basis of these groupings varies according to the features of fruits or growth of the fruit plants that have been under classification at the time.

Knowledge of classification of horticultural plants is very useful to the horticulturists because it serves: (1) to identity and name them, (2) to afford at least some idea of the closeness of their relationship i.e. line of descent to other kinds, (3) to suggest with what other kind they possibly may or may not be interbred or crossed, (4) to suggest the kinds with which they possibly may or may not be inter-grafted, and (5) often to suggest certain soil and the cultural requirements, climatic adaptations etc. However, the classification of fruit trees or fruits and vegetables on the basis of consumer’s rating also gained attention in recent years. The consumers’ rating is mainly based on the size, shape, nutritive value and marketability of them. Each of these classifications is quite different from the other classification or groupings.

Basically, the fruit trees, as suggested by many authors, have been classified on the basis of their botany comprising of taxonomic ancestry, morphologic features, physiological functions, adaptability etc. or on the basis of agricultural and horticultural requirements. But the consumers’ rating has not been properly covered in the earlier classification. Generally based on botanical relationship the plants are classified as under.

Soil- Soil is the upper most crust of earth surface which supports plant growth. It is defined as a three phase system in which plants grow. These phases are solid, liquid and gas and are essential. Solid part is frame which provides space for other two. This consists of minerals, clay minerals and organic matter. The soil is also a living system with millions of microbes that breakdown organic matter and builds it again.

Some points are following

Microbes are essential and survive only when soil is well aerated and rich in organic matter and devoid of waterlogged conditions.

Texture of soil depends on the size of solid particles and classified as gravel, coarse and fine sand, silt and clay.

Soils are classified according to relative distribution of these particles and there are 12 textural classes.

Likewise, arrangement of these particles is referred as structure, and both texture and structure lend soil physical properties like water holding capacity, aeration and bulk density.

Generally loamy soils and crumb structure are most preferred for fruit crops.

According to level of organic matter, soils are classified as mineral soil or organic soil and soil having more than 20% organic matter is organic soil like peat and muck.

Water

Water is one of the most important inputs essential for the production of crops. Plants need it continuously during their life and in huge quantities. It profoundly influences photosynthesis, respiration, absorption, translocation and utilization of mineral nutrients etc. Both its shortage and excess affects the growth and development of a plant directly and consequently its yield and quality.

Soil needs the application of water to:

Remove stress condition.

Release nutrients in the soil solution for absorption by plants.

Leach or wash out injurious salts from the soil.

Preparation of land for raising crops.

To maintain the temperature and humidity of the soil micro-climate and the activity of soil microbes at optimum level.

For the normal aeration and functioning of roots and shoots of the plants.

Excess water needs to be removed for the normal aeration and functioning of roots and shoots of the plants

Excess water creates unworkable soil condition.

Nutrients

The 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 materials. These materials constitute among other things, foods for humans and animals and a range of raw materials for various industrial uses. Feeding of plants with nutrients is termed as nutrition. Successful growth and production of the plants in general requires a proper supply of the 17 elements. These elements are regarded as essential to life in higher plants.

Weed

Weed in orchards reduce crop yields by competing for moisture, nutrients, light and space. They also harbour insect pests and diseases. When they become large they interfere with orchard operations. Some of weeds climb on the trees and shade the foliage. There are some weeds which are parasitic partially or completely on the host tree e.g. Striga and loranthes on mango.

Mulching

It means covering of soil surface by some organic or inorganic materials for conserving the soil moisture besides covering on the soil moisture several other advantage of mulching. The materials which are used in mulching called mulch.

Nursery

Nursery is a place where seedling, saplings or any other planting materials are raised, propagated, multiplied and sold out for planting. The prerequisites of a successful and remunerative fruit production are the availability of true-to-type, healthy and good quality planting materials. Setting up of a fruit nursery is a long term venture and requires careful planning and expertise, because mistakes committed initially cannot be rectified easily and may adversely affect the return from the investment. Thus, one should pay due attention on every aspects when nursery is to be established.

Propagation

Plant propagation means multiplication of plant by sexual or asexual method. The success in plant propagation depends on a thorough knowledge of the growth of plants, choice of suitable method and technical skill. The propagation of plants may be done either by the gametes or from the somatic cell, tissues or organs. In other words, propagation may be done by sexual methods or by asexual methods. The details of the methods are presented below.

Orchard

Establishment of orchard is a long term investment. It is require a proper planning, any mistake during the selection of site, planting distance, choice of crop/variety, quality of nursery stock etc. reflect greatly on the orchard performance and efficiency.

Planting System

Main objective of layout is maximum number of plant accommodated in per unit area without affecting the efficiency of production. If more than one fruit is included in the orchard plan, each kind should be grouped into individual block. Similarly fruit ripened in particular season should be grouped to facilitate convenience in watch and ward, harvest and post harvest handling. Some kind of fruit trees need pollinators/pollinisers for improving the fruit set.

Horticultural plants are grown for their produce like fruit, vegetable, flower, medicinal component, spices etc. Therefore, these plants should be managed in such a way that human desires for the purpose of growing them are fully satisfied in terms of quality and quantity of produce. This demands direct manipulation of plant growth itself or plant environment through various inputs. In manipulation of plant development, training and pruning are important for which our knowledge about plant development and its phenology has to be complete. These practices are important in fruit crops.

Bearing

Bearing is connotation of flowering and fruiting. When a fruit tree flowers and fruits, it is said in bearing condition. Different fruits have different bearing habits, inflorescences, types of flower, mode and medium of pollination, pollen viability and all these account a lot for the bearing of fruit plants.

Bearing habit

If one observes a mango tree, he/she may find it does produce the fruits terminally on a shoot and it citrus he/she finds the fruits always produced laterally in the leaf axils. The manner or patter in which a plant produces its fruit is known as bearing habit or fruiting habit. Bearing habits are specific to the kind of plant. In determining the bearing habit of any plant three points are to be considered.

The quantitative increase in plant body such as increase in the length of stem and root, the number of leaves etc., is referred to as plant growth whereas, the qualitative changes such as germination of seed, formation of leaves, flowers and fruits, falling of leaves and fruits is referred as development. Utilization of these substances for proper development of the plant is regulated by certain chemical messengers called plant growth substances or plant growth regulators, which in minute amounts increase or decrease or modifies the physiological process in plants. Plant growth substances are the chemical other than nutrient which required in very small amount but without which plant can not complete their physiology.

The two sets of internal factors, viz., nutrition and hormone control the growth and development of the plant. The raw material required for growth is supplied by nutritional factors which include the minerals, organic substances the protein, carbohydrates, etc.

Phytohormones: These are the hormones produced by plants which in low concentrations regulate plant physiological process. These usually move within the plants from a site of production to a site of action.

Plant growth regulators: These are organic compounds other than nutrients, which in small amounts promote, inhibit or otherwise modify any physiological process in plant.

It may be defined as any organic compounds which are active at low concentrations (1-10 ml) in promoting, inhibiting or modifying growth and development in plants. The naturally occurring (endogenous) growth substances are commonly known as plant hormones, while the synthetic ones are called growth regulators.

Plant hormones: It is an organic compound synthesized in one part of plant and translocated to other parts, wherein very low concentration causes a physiological response.

The plant hormones are identified as promoters (auxins, gibberellin, and cytokinins), inhibitors (abscisic acid and ethylene) and other hypothetical growth substances (Florigen, death hormone, etc.).

The current status of advances in fruit breeding is through the development of different scientific approaches augmented by ever-increasing knowledge and application of genetics, statistics and biotechnology. These innovative approaches very specific for a species in most of the cases, are the major tools of the fruit breeders to tackle the different objectives of fruit improvement programme at present Fruit improvement is a very slow process due to the long generation cycle varying from species to species, thereby reducing the chances of exploiting genetic recombination. Besides this factor, most of the fruit species are either highly heterozygous or polyploidy in nature. Due to this reason the asexual propagation of fruit plants is a conventional means while wide segregation occurs upon sexual reproduction. Such expectation is not unlikely because the types selected as commercial varieties are definitely to be vigorous ones, and a positive correlation exists between vigour and heterozygosity.

This discussion on breeding of fruit plants involves different aspect of the species concerned is so essential as well as fundamental that discussion of them must procede any consideration of breeding methods themselves. The plant species are grouped into two-self-pollinated and cross-pollinated. These two groups have emerged on the basis of pollination mechanism which plays significant role in the method of breeding application. To emphasize the difference in the reproductive systems of these two groups one should know the details about floral biology, mechanism of pollination control, reproduction by asexual and sexual means and self and cross-pollinated plants.

Physiological disorders are abnormalities in plants which are associated to non-pathogenic factors. A plant or its parts may show unusual growth, function or deformity. Such abnormalities are widely referred to as disorders. These may be incited by nutrients deficiency or excess, hormonal imbalance, abnormal growing conditions etc. Some commonly observed disorders have been dealt in here suitably.

Seedlings of several vegetables are first raised in well prepared nursery beds, followed by transplanting in the field. Raising of seedling in the nursery beds is economical as well as easier to take care of young, tender seedlings against pest and diseases. Further, raising of seedlings in nursery allow more time for land preparation.

Site and soil for nursery

In selecting a site for nursery beds, following points should be considered viz sunny situation, good drainage and irrigation facilities. Sandy loam soil with plenty of organic matter are ideal for starting nursery beds. In case of heavy soils it is desirable to add coarse sand to modify the soil condition. Before sowing seed it is essential to sterlize the beds by steam or formaldehyde or any other chemical to do away with problem of damping-off disease. Burning of leaves or straw in the beds is quite helpful in controlling certain soil borne diseases and pests.

Seed

A seed is a mature ovule consisting of an embryo together with stored food, all enclosed by a protective coat. It is product of the ripened ovule of gymnosperm and angiosperm plants which results as a consequence of fertilization and some growth within the mother plant formation of seed completes the cycle of reproduction. The embryo develops from zygote and the seed coat from the integument of ovule. A seed has three main parts these are seed coat, endosperm and embryo. Embryo includes the root, the cotyledon and embryonic leaves. Seed is located inside fruit and a fruit is a mature ovary. In broad sense any plant part which is used for commercial multiplication of crop is called seed. Thus in case of potato stem and tuber are also known as seed. Improved seed results in (1) Better germination (2) Vigorous seedling growth (3) Higher crop stand (4) Better quality of produce (5) Ultimately in higher crop yield.

Development of seeds: Successful pollination and fertilization are the prerequisites to produce a viable seed. During pollination the pollen grains are transferred from anther to the stigma and get stuck there in the sticky fluid secreted by the stigma. The fluid contains sugar which induces germination of pollen grains. The pollen tube grows downward through the style in the ovary until it reaches the embryo sac and discharges two male gametes-one is fused with a female gamete and forms the zygote (2n) and the other is united with two pollar nuclei to produce endosperm (3n). The zygote develops and gives rise to embryo embedded in nutritive tissue developed from endosperm. The nucellus tissues surrounding these structures provide necessary energy for their proper development. Like fruit, the seed also exhibits sigmoid and sometimes double sigmoid pattern of growth. Various changes occur during the course of seed development and the sequences of development may vary from species to species keeping the basic theme unaltered.

The purpose and the mode of marketing of vegetables determine the type of vegetable gardening. The various types of vegetable gardening are as follows.

Home or Kitchen gardening

Market gardening

Truck gardening

Processing gardening

Vegetable forcing

Seed production gardening

Floating vegetable gardening

Vegetable crops: A seed is borne on fruit and fruit is a mature ovary and ovary is a typical part of flower. Flower in angiosperm, consists of four parts these are calyx/sepal, corolla/petals, androecium/stamens and gynocium/pistil, outer whorl of flower is collectively referred to as calyx. The individual components of calyx are called as sepal. Petals are collectively referred to as corolla. Petal is a unit of second inner whorl after sepals. Stamen is part of flower bearing the male reproductive parts composed of anther and filaments. Pistil is part of flower bearing the female reproductive parts composed of stigma style and ovary.

Seed Production Techniques in Vegetable Crops

Share (%) of F₁ hybrids- Cabbage 85%, Watermelon 70%, Okra 23%, Tomato 80%, Chilli 80%, Cauliflower 50%. Among the Asian countries, India is the 2^nd largest production of hand pollinated hybrid seed in vegetables.

The planning of a garden is an art. It is said that a poet is born, and in that sense a garden architect is also born. But that does not mean that a garden architect has nothing to learn. On the contrary he should learn enough of geology, geography, garden history, styles of gardening, and above all should have a profound knowledge about plants. It is imperative to know at the outset what is meant by landscape gardening. A landscape may be defined as any area, either big or small, on which it is possible or desirable to mould view or a design, whereas landscape gardening may be described as the application of garden forms, methods, and materials with a view to improving the landscape. The art of designing is known as “landscape architecture,” although the older term landscape gardening” is also popular.

Before discussing the principles of gardening in detail, it will be worthwhile to make some useful suggestions. The first and the foremost thing are not to imitate another garden which has secured a prize in a competition. One has to develop one’s own design giving due consideration to the local conditions. One more mistake which is commonly made is to plant many more specimens than a garden can accommodate causing overcrowding. In a landscape garden any difference in levels has to be taken advantage of, but in a perfectly flat land it will be costly to create artificial undulations. In each garden the care should be at least one feature or there be a second these two should harmonize with each other. Before planning a design are must be sure for what purpose the garden is utility or beauty or both.

Lawn

Lawn is a natural green carpet, and it is important feature of a landscape and a garden without a lawn is not considerd complete. Lawn is an area of land closed mowed grasses it is primarily developed for aesthetic and recreational purpose. A lawn is an integral part of a garden and landscape besides aesthetic and recreational purpose and several other purposes. Lawn provides a place for taking rest after tiring of the day, holding parties, social functions, passive and active recreation. Distinguishing characteristic of turf grasses is the ability to with stand close mowing and still providing a functional dense healthy ground cover. Lawn is also called as heart of garden. Lawn can be called as turf pitch a field, sod, yard, are green depending upon the plantation usage continent. Lawn is a ground cover of perennial grass, ditch, persists enclose mowing and require proper management practice.

J.B. Olcoth designed first experiment in lawn grass at Monchester in USA in the 19th century. Festuca and Agrostis species were used to make turf (Lawn) during 1880 in U.K. In the early 19th century lawn become wild spread out side of parks golf course. Now a day in many metro cities of India lawn has become a cultural of the passion of many homes.