eChapters

The Mother Nature bestowed humanity with about 250,000 known plant species and perhaps the same or may be higher number of unknown plant species. Out of this treasure, 80,000 plant species are edible but human beings have probably exploited about 3,000 of these species for food and was cultivating about 150 on a commercial scale. However, largely human beings consumed only 20 different kinds of crops the world over and four of which viz. rice, wheat, maize and potato are supplying about 60 % of total calories. Under the circumstances, the food crops base even for well-known crops are shrinking at an alarming rate and in this process, many species have extincted from man’s food bowl. While doing so, we have considerably reduced the range of organic compounds that we now consume, thus making ourselves vulnerable to various stresses. Realising  importance of diverse food base in our life, thinking is going on among people of all lifestyles that more and more crops particularly those, which are known to be edible but have remained as “under-utilised crops”, should be brought into cultivation. This will ensure both food and nutritional security of people. Among these, tuber crops constitute an important crops group, which was sustaining food security much before agriculture came into existence.

Malvaceae, the mallow family, carries herbs, shrubs or trees comprising about 75 genera and perhaps as many as 1,500 species. Hibiscus and Abelmoschus are two important genuses under this plant family. Several species of plants of potential uses come under these two genera about which limited publications are available. 

Hibiscus

Hibiscus is a large genus of about 200-220 species of flowering plants in  Malvaceae, native to warm temperate, subtropical and tropical regions throughout the world. The genus includes both annual and perennial herbaceous plants and woody shrubs and small trees. The leaves are alternate, simple, ovate to lanceolate, often with a toothed or lobed margin. The flowers are large, conspicuous, trumpet-shaped, with five petals, ranging from white to pink, red, purple or yellow, and from 4-15 cm broad. The fruit is a dry five-lobed capsule, containing several seeds in each lobe, which are released when the capsule splits open at maturity.

Common names:  Sessile joyweed, Joyweed, Dwarf copperleaf (English), Geluti (Hindi), Ponnanganni green (Tamil) Latin names: Alternanthera sessilis (L) Syn: Alternanthera nodiflora R. Br., Gomphrena sessilis (L), llecebrum sessile (L) Linnaeus belongs to family Amaramlnaceaes.

Habit and Habitat
 
Perennial herbs, pantropical, damp shady areas, swamps, pond margins, shallow ditches, road sides, low-lying waste lands, damp pastures, cultivated areas. In New Guinea, «a plant of damp places; ditches, wet headlands, roadsides; sometimes a weed of plantations, particularly at altitudes of 1500 m or higher. From near sea level to over 2000m» (Henty & Pritchard, 1975). In Tonga, «occasional as a waste area weed» (Yuncker, 1959).

The Cucurbitaceae family consists of nearly 100 genera and over 750 species. Although most of them have Old World origin (Whitaker and Davis, 1962), many species originated in the New World and at least seven genera have origins in both hemispheres (Esquinas-Alcazar and Gulick, 1983). There is considerable genetic diversity within the family and the range of adaptation for cucurbit species includes tropical and subtropical regions, arid deserts and temperate locations. A few species are adaptable to production at elevations as high as 2000 m. The genetic diversity in cucurbits extends to both vegetative and reproductive characteristics. There is considerable range in the monoploid (x) chromosome number (Jeffrey, 1990) including 7 (Cucumis sativus), 11 (Citrullus spp., Momordica spp., Lagenaria spp., Sechium spp., and Trichosanthes spp.), 12 (Benincasa hispida, Coccinia spp., Cucumis spp. other than C. sativus, and Praecitrullus fistulosus), 13 (Luffa spp.), and 20 (Cucurbita spp.).
 
Archaeological evidence indicated that cucurbits were present in ancient and prehistoric cultures. Lagenaria was associated with man as early as 12,000 BC in Peru (Esquinas-Alcazar and Gulick, 1983). Archaeological expeditions in the Oaxaca region of Mexico have reported that Cucurbita pepo was associated with man as early as 8500 BC and cultivated by 4050 BC (Esquinas-Alcazar and Gulick, 1983). Written Chinese records describing the use of cultivated cucurbits have been found as early as 685 BC (Herklots, 1972).

Indian arid zone is one of the largest sub-tropical deserts of the world, of which 20 % is arid and the remaining semi-arid with varied habitats. The hot arid region is spread over 31.7 million ha mainly in Rajasthan (19.6 m ha), Gujarat (6.22 m ha), Andhra Pradesh, Punjab and Haryana. Rajasthan is the largest state in the country covering approximately 34.2 m ha geographical area out of which 27.1 m ha (79.08 % of total area) is laying in arid and semi-arid climate, spread over 21 out of 32 districts. Western part of Rajasthan is under hot arid climate (Thar Desert) and it extends from 24^º 37’ to 30^º 10’ N latitude and 690 29’ to 76^º 05’ E longitude. Barmer, Bikaner, Churu, Ganganagar, Hanumangarh, Jaisalmer, Jalore, Jhunjhunnu, Jodhpur, Nagour, Pali and Sikar districts of Western Rajasthan account for 63.4 % area of  hot arid realm of India. Apart from these, about 10 % area each of Sirohi, Ajmer and Jaipur districts are also in arid region. Punjab and Haryana bound it in North and Gujarat in South. The Aravali hill ranges provide a natural boundary with semi-arid Eastern Rajasthan. In the West, it has a long international boundary with Pakistan.

The Cucurbitaceae family is characterized by long training viny stems. There is variation for flower size and colour among the species but all of them have similar general morphology. The species are open pollinated and self compatible. Most of them are either monoecious (eg. Cucurbita spp.) Or andromonoecious (e.g. common in melon). Other species show gynomonoecy, androgynomonoecy, androecy, gynoecy, hermaphrodite or dioecy. Chow-chow is the only member of the Cucurbitaceae that is viviparous, contains single seed and propagated by planting whole fruit. The Indian gene centre has rich diversity in genetic resources of ridgegourd (Luffa acutangula), bottlegourd (Lagenaria siceraria), bittergourd (Momordica charantia), ashgourd (Benincasa hispida), snakegourd (Trichosanthes anguina), pointed gourd- parval (Trichosanthes dioica), pumpkin (Cucurbita spp.) and roundgourd (Praecitrullus vulgaris). Cucurbits are of tremendous economic importance and are cultivated throughout the world from tropical to sub-temperate zones. China, Turkey, India and Iran are important cucurbit growing countries. In India, this diversity is concentrated in Indo-Gangatic plains, north eastern region, north western Himalayas, the Western and Eastern Ghats and sporadically in the tribal dominant belts of central India.  More diversity occurs in Cucurbita spp. in the north east as also for ashgourd, bottlegourd while for Luffa, it is more concentrated in the eastern peninsular tract.

Ber (Chinese date, Chinese fig or bore) (Ziziphus xylopyrus) is an important minor fruit of India. It is a hardy fruit tree cultivated all over India and also known as poor man’s fruit. It is widely cultivated in Punjab, Haryana, Rajasthan, Uttar Pradesh, Madhya Pradesh, Bihar, Gujarat and Maharashtra. Ber does well even under marginal growing conditions and provides quality yields at low cost (Shukla, 1996). Fruits are eaten fresh but the other forms like dried, candied and squash can also be prepared from ber. Stem bark, root and leaves have medicinal values. Leaves of ber are used as fodder in dry regions. Ber tree is a host plant for rearing the Tachardia laccad, a lac insect (Sharma and Kore, 1990).

Plant genetic resources are the key components of crop improvement because of development of precision breeding system through biotechnological approaches as well as conventional system of breeding like selection and hybridization. Breeding system of hybridization is replaced by cybrid technology that facilitates transferring more qualitative and quantitative traits rapidly within incompatible genotypes. Aonla is mainly recognized for its high nutritive, medicinal and therapeutic properties. It contains high amount of vitamin-C (500-1500mg/100g), it is also rich in pectin, iron, calcium and phosphorus. Dried fruits of aonla can be used in curing haemorrhage, diarrhea, chronic dysentery, diabetes, jaundice, dyspepsia and cough. Recently, aonla gained more popularity in arid and semi- arid region of the country because of its hardy nature, prolific bearing capacity and ability to grow under various adversities as a remunerative crop (Shukla et al.2002). Aonla is the main ingredient of Chavanprash and Triphala powder, used for curing different   human ailments. Fruit contains a chemical substance gallic acid and leucoanthocyanin, having antioxidant property.

India produces all deciduous fruits including pome fruits (apple and pear) and stone fruits (peach, plum, apricot and cherry) in considerable quantity. These are mainly grown in the North-Western Indian States of Jammu and Kashmir (J&K), Himachal Pradesh (H.P.), Uttarakhand and in Uttar Pradesh. The North-Eastern Hills region, comprising of the States of Arunachal Pradesh, Nagaland, Meghalaya, Manipur and Sikkim also grow some of the deciduous fruits on a limited scale. The sub tropical region lies between 150 and 300 north of equator covering North Indian plains, the gangetic basin, large parts of North eastern state, western ghats, nilgiri regions etc. In this zone spring is generally frost free and chilling availability ranges from 50-500 hours. This region is not considered proper for temperate fruit growing but grows several low chilling varieties of peach, plum, pear etc. Deciduous fruits, such as peach and nectarine, require accumulated exposure to cool temperatures during winter dormancy for bud break and the resumption of normal growth the following spring. Minimum amount of accumulated cool temperature exposure needed for normal growth, which varies by cultivars, is referred to as the chilling requirement. Due to introduction and adaptation of low chilling cultivars of peach, plum and pear, they are also now being grown commercially in certain areas of the north Indian plains.

Apricot (Prunus armeniaca L) is the most important fruit crop of cold arid regions of India. It is one of the most delicious of temperate fruits having pleasing flavour and truly one of the most delectable of the stone fruits.  Exceptional fruit quality consists of blending of sugar and acidity and strong apricot aroma. It has been appreciated and grown for thousands of years on slopes of mountains in Asia and at least two thousand years in Europe.  There are many uses of apricot. It is enjoyed as fresh fruit but a large portion of the production worldwide is preserved primarily by drying. In China, apricot was not only dried but also preserved by salting and smoking. In Japan, apricot (mume) flowers are revered for their beauty and are used since 7–8th century for ornamental purposes.

Giant granadilla, Passiflora quadrangularis L. (syn. P. macrocarpa M.T. Mast.) is the largest fruit in the genus Passiflora. With more than 450 species, Passiflora is the most important genus of family Passifloraceae. It is further divided into 24 subgenera (Killip, 1938). Most of the species producing an edible fruit belong to subgenera Passiflora and Tacsonia. Many species have ornamental interest because of unique and spectacular flowers, or are used for their sedative, antispasmodic, antibacterial, and insect-resistant properties.

The Andaman and Nicobar group of Islands, popularly known as the Bay islands, consists of 572 islands, islets and rocks, situated off the Eastern coast of India. The Islands are covered from coast to coast with an almost impenetrable growth of luxuriant tropical rain forests. The luxuriant growth of dense forests with tangled mass of climbers, lianes, canes and plant communities provide an additional source of income. Many species of bamboos, bushes, shrubs and stunted trees have tremendous values (Mondal, et al 2000). Most of the diversity is still collected from wild forest habitats largely composed of trees, shrubs and other perennial vegetations. Underutilized fruits provide food, nutrition and sustenance to the natives. Broadly, such underutilized diversity in edible fruits falls into four categories (Groot et al 1993).

Genetic resources for food and agriculture are the biological basis of world food and nutrition security and they directly support the livelihood of people. Horticultural genetic resources are a few of biological assets available to resource-poor farmers to ensure sustainable production to improve livelihood options. Genetic diversity gives resource-poor farmers a low cost option to manage the shocks and vulnerability of production systems by its ability to adopt to changing environments. It is the foundation upon which plant breeding depends for the creation of new varieties and is, therefore, of critical public value for global food security. The rapid loss of genetic diversity (genetic erosion) is a worldwide concern and is particularly severe among crop landraces. Farmer’s varieties or landraces may contain co-adapted gene complexes that have evolved over decades and are the most valued genetic resources as they provide options for a range of climatic and edaphic stresses. Therefore, agricultural biodiversity has a critical public value for global food security (FAO, 1978).

Aonla or Indian Gooseberry (Emhlica officinalis Gaertn. syn. Phyllanthus embfica L.). belonging to family Euphorbiaceae. is an indigenous fruittree to Indian sub continent. It is one of the most important commercial crops suitable for marginal soils and various kinds of waste lands particularly salt affected lands. A lot of genetic variability is available in India with respect to growth and fruit quality characteristics of aonla. Almost all the budded varieties of aonla were selected from naturally occurring superior chance seedlings having in view their earliness, lateness, hardiness to adverse conditions, yield and superior fruit quality.

1-or successful aonla orchards, it is utmost necessary to have basic knowledge of various cultivars suitable for a particular set of environmental and soil conditions.

Plants yielding oilseeds are economically important in India next only to food crops and play an important role for sustainability of  cropping systems and soil health. Oilseeds scenario in the country underwent a sea change in  last fifteen years. India changed from net importer in  1980s to a net exporter  during  early 1990s. Again, it is back to net importer importing more than 40 % of its annual edible oil needs. Country’s demand for edible oils is  rising to double  the current level of 4% (as against productivity growth of 2% in 1986-2001) in  next 12 years (Hegde 2004). To meet  challenges of oilseeds production, there is  need to adopt multi-pronged strategy which involves enhancing production through area expansion and productivity improvement through improved technologies and value addition . As a progressive step in this direction of self sufficiency, there is  need to identify alternative oilseed trees/plants which can be grown in wastelands. There are more than 300 different kinds of tree species which bear seeds  rich in oil and  introduction of simarouba is an important step in this direction. National Oilseeds and Vegetable Oil Development (NOVOD) Board under Ministry of Agriculture  identified simarouba as a potential Tree Bearing Oilseed (TBO) for popularization in India and placed it in  first place in their list of importance.

Tamarind (Tamarindus indica) or Imli is also called  Indian Date. It is a large broad leaved, tropical tree found in India and many parts of Asia.  Tamarind is native to tropical Africa and grows wild throughout  Sudan. It was introduced to India so long ago that it is now reported as indigenous. Sometimes during  sixteenth century, it was introduced into America and today it is widely grown in Mexico.
 
There are large areas of marginal and waste lands, which are not suitable for cultivation of fruits like banana, citrus, sapota, litchi, mango, pomegranate etc., either due to poor quality of soil or lack of water resources. Such lands are suitable for  cultivation of underutilized fruit crops like tamarind which is not so popular among  farmers due to following reasons:

Karonda is an indigenous, under utilized fruit of India. It is a hardy multipurpose horticultural bush flourishing well without much care in arid and semi-arid areas. At present ,emphasis is being laid on protection and  production value of karonda plant. It is grown as hedge for beautification which  serves as one of the best bio-fencing materials because of  thorny  nature. It is also grown as an ornamental plant due to its beautiful cherry like fruits. Karonda plants are useful in many ways as detailed  below:
 
Fruit: Karonda fruit is a rich source of iron and contains a fair amount of vitamin C, and therefore very useful for curing of anaemia and has antiscorbutic properties. Enthomedically,  fruits are used as an astringent, antisorbutic and as a remedy for biliousness. Mature fruit contains high amount of pectin  and therefore, besides being used for making pickles and chutney, it can be exploited  for making jelly. Raw fruit can be used for making chatney.

Leaf: Karonda leaves are palatable and contain a fair amount of nutrient which are browsed by sheep, goats and camels in arid and semi arid areas.If fruits fall on ground, enrich soil by adding organic carbon and other mineral nutrients. It reduces evaporation  from  soil underneath due to dense foliage. Leaves  are used for feeding silk worm.  Leaf decoction is used against intermittent fever, diarrhoea, oral inflammation and ear ache.

Morinda citrifolia L is a unique horticultural plant belonging to Rubiaceae family. It has a tremendous demand because of its high medicinal value. Increase in demand has led to commercial farming of the tree. Noni is an ideal plant for mixed farming with other horticultural plantations. There is concurrent efforts to select early bearing plants with big size and fruits.  Noni can be grown in any type of soil under adverse climatic conditions.  Crop Improvement, nutritional requirement, water requirement, pest and disease management are the research priorities in Morinda citrifolia.

Indian Noni (Morinda citrifolia) is popularly known as Indian mulberry belongs to Rubiaceae family.  It is also called great Morinda, Cheese fruit, Mouse’s Pine Apple, Nono, Jumbie bread fruit, Hog apple. Noni was one of the most widely used medicinal plants in Polynesia prior to European contact, and continues popular among modern population. Noni is commonly known as canary wood in Australia, Kura in Fijii, mora de la India in spanish, nono in Tahiti and Nin in Marshall Island. Medicinal values of Noni were known to man many centuries ago. Uses of Noni were mentioned in Indian ethnopharmacology and ayurvedic medicines. Noni is grown as medicinal plant in most of  South Indian temples as sacred plant like basil (Tulasi). In India, it is called by several names in different  regional languages like nuna, manjanathi, manjanuna in Tamil,  molugu, mogal, bundamaddi in Telugu, kakaiplam, kattapitalavam, mannanatti in Malayalam, tagatemara, haladipavete in Kannada, Ach Al in Hindi, Paphan, Achchhulca in Sanskrit, Aseti, Nagkura, Mundari solidaru in Marathi.

Mango is the choicest fruit of tropical world. Originated in Indo-Malayan region (Mukherjee, 1985), more than one thousand varieties are under commercial cultivation in India (Mukherjee 1949). South Indian varieties of mango are distinct (Yadav and Singh, 1985).  Naik and Gangolly (1950)  described 135 South Indian varieties, taking fruit character as the main criteria. North Kerala experiencing humid tropical climate is an important zone of variability of mango (Kannan, 1982). Polyembryonic mango cultivars like ‘Vellaikolamban’, ‘Kurukkan’ and ‘Bappakkai’ are traditionally grown here. Over the years, there is erosion in  gene pool of rich varietal wealth due to deforestation, urbanisation and large scale rubber cultivation in Kerala. Establishment of field gene bank is an important ex situ conservation strategy. Systematic attempts to conserve  genepool  resulted  in collection of  more than 1266 varieties in various field gene banks in our country (Chadha, 1976). Field Gene Bank (FGB) has the advantage of being continuously evaluated and desired accessions can immediately be utilized directly or in breeding programmes. Field gene bank very often represents only a fraction of variability of the gene pool and  enrichment of the collection is always required for capturing  available diversity.

Spine gourd or teasle gourd (Momordica dioica : Roxb Syn.Momordica roxburghii G. Don, M. wallichi, M J Roem) is a rhizomatous, perennial and distinctly dioecious species of family Cucurbitaceae and  grows widely in many parts of India, mostly confined to  Eastern and South Eastern states. Vernacular names are kartoli,kakrol,meethakarela, padora, bhatt karela, palupagal, tumba, tumpai, golkandra, kankad, kankera, bara-karela, kankoda, kankodan, kantola and phalguni. In India it is mainly grown in Orissa, Bihar, and West Bengal .It is  found in nature in the Punjab, Uttar Pradesh, Rajasthan, Madhya Pradesh, Kerala and Maharashtra especially in areas with the least human interference. This is  a delicacy for its typical taste, attributed to high seed protein content. It also contains high amount of carotene (162 µg/100 g of edible portion) (Gopalan et al., 1982) and its tuberous roots have medicinal value too. It is a cheap source of vitamins and minerals (Bhuiya et al., 1977). This vegetable is gaining popularity  because of its high demand in  market. Certain limitations like lack of awareness among  farmers, non-availability of quality planting materials of standard varieties, unpredictable sex ratio in seedling progenies are arresting the expected spread of this nutritious vegetable (Ali et al., 1991).

Clasping stemmed Solena or diversely leaved Melothria or creeping cucumber (Solena amplexicaulis Lam. Syn. Bryonia amplexicaulis (Lam), Melothria heterophylla (Lour), Melothria angulata Chakrav) is an indigenous cucurbit vegetable occuring in nature nearby cultivated areas on hedges or in open fields In Greek Solen means’ a tube,pipe’ refering to the nature of its flowers. The vernacular names are Bon-kundari, kudari, makal, mahakal (bengali), gometti (marati), kanduri, kuduri (bundelkhand), bankakra (champa), gometi (gujarati, anatmul, mahakal, taarali, kaduri (hindi),makirla (chattirgarh), kaage mari balli (kanarese) etc. This is a perennial vine, dioecious in nature. Tender fruits are used as salad, curry and  fried vegetable. It has significant medicinal value also.  In tribal regions of Orissa, fruits of Melothria are considered as delicacy. Visualizing the delicate nature of its fruits, it has great potential as a salad crop in  future.

Syn.cordifolia Cogn.,C.indica Wight and Arn,Bryonia grandisL. Family.Cucurbitaceae) is an aggressively climbing vine that  spreads quickly over trees, shrubs, fences or other supports. It is also called  scarlet fruited gourd or little gourd. The name is derived from the Latin coccineus, meaning scarlet,in reference to fruit colour (Wagner et al.,1999). Vernacular names are kundru (hindi), kovakka, kova (malayalam), kovakkai, kovai(tamil), thondakayi (kannada), dondakaya (telugu). Coccinia shoot is a good source of calcium, iron, and fiber and has good texture (Anon., 2002). It is grown mostly in homestead farms for tender fruits in almost all regions of the country. It bears fruits almost through out the year where mild winter prevails. In regions where severe winter occurs, it bears fruit for 8-9 months. Although this is considered as a an under utilized vegetable, it is grown extensively in Chattisgarh, West Bengal, Bihar and Karnataka on a commercial scale and giving remunerative returns to  farmers. Availability of better cultivars and knowledge of  many other preparations and uses of this crop can propel its evolution from an under utilized species to an important horticultural crop in Indian Agriculture.

Chow-Chow [Sechium edule (Jacq.) Swartz] is used in many parts of Latin America, humid tropical regions of Central America and Southern Mexico. It is cultivated in South East Asia (India, Malaysia, Indonesia and Phillipines), Central and Western Africa, Central and South America (Brazil) and other tropical regions. (Dutta 1994). In India, local cultivars are commonly grown in coastal and low-hills (1000-2000m) of Maharashtra, Karnataka, and Tamilnadu. In Tamil, it is called “Seeme Kattrikkai” (Bailey, 1947). It is an important part of dietary system of tribals of  North East Regions. It is found in kitchen gardens of every tribal. It is found in almost all states and regions but maximum variability is found in Sikkim, Mizoram and Meghalaya (Yadav et al., 2005). Its variable fruits and roots, are important elements in diet of people. Chow-Chow is widespread and is an important export crop for  Latin American countries, much still need to be learned  about this crop (Rafael Lira Saade,1996). Chow-Chow is a single seeded fruit of  Cucurbitaceous family (MacGillivray, 1953). It is a perennial rooted vine that bears edible fruits (Thompson and Kelly, 1957). In subtropical and tropical regions, it produces large edible tuberous roots. It thrives under moderate temperature in  tropical or semi-tropical environment, though it can also be successfully grown under high temperature near sea level. Chow-Chow is a herbaceous perennial creeper (Choudhury, 1967) and is a robust grower in warmer months of year and during  cold weather of July and August  plant dies back temporarily. It has a viviparous type of germination (Patnaik, 1967). S.edule is called chayote, probably from  Greek ‘Sekos’ to  fatten in a fold because it was fed to hogs ( Bailey, 1963).

Basella (Basella alba syn Basella rubra) is also known as Poi, Ceylon spinach, Malabar spinach, Indian spinach or vine spinach. It is a popular leaf vegetable grown in almost all parts of India and widely grown in North-East and South India. Besides India, it is widely cultivated in tropical Asia and Africa. It is a climbing perennial plant, but is sometimes cultivated as an annual vegetable. The plant is succulent with tender leaves. It is a fast growing, productive leaf vegetable for home gardens and market growers. 

Composition
Young shoots and leaves of Basella are a rich source of calcium, iron, and Vitamins A and C.

Uses
Fresh tender leaves and stems are consumed as leaf vegetable after cooking. It is preferable to cook the leaves in soups and stews as half of soluble solids may be lost by boiling in water. Red cultivars contain a colouring matter in leaves, stems and ripe fruits reported as a dye for colouring food. Because of its mucilaginous nature of leaves and stems, it is used as poultice. Juice of leaves is prescribed against constipation, especially for children and pregnant women (Burkill, 1935).

Major cucurbits grown in India are cucumber, watermelon, muskmelon, ash gourd, pumpkin and squashes, snake gourd, ridge gourd, smooth gourd, bottle gourd, round gourd, bitter gourd, pointed gourd, ivy gourd,pointed gourd and oriental pickling melon. After independence,a lot of breeding work were done in these crops at many research institutes in the country which  resulted in  release of several high yielding/disease resistant varieties/hybrids.

Being warm season crops, cucurbits are tropical in origin, mostly in Africa, Tropical America and Asia. Flowering in cucurbits normally start in 40 to 45 days after sowing depending on weather conditions. Sequence of flowering follows a set pattern, namely the first 4 to 6 flowering nodes would bear staminate flowers and later pistillate flowers appear. Many sex forms are seen in cucurbits viz., monoecious, dioecious, gynoecious,trimonoecious, gynomonoecious and andromonoecious. Sex modification is also possible in cucurbits by exogenous application of plant growth regulators. GA₃ and AgNO₃ are used for inducing male flowers in gynoecious lines. Conversely,ethrel and TIBA  are used to promote greater number of female flowers. This kind of sex modification is more useful and practicable in  cucumber and bottle gourd where continuous and simultaneous flowering, fruit set and fruit picking take place.

In ancient days spices and herbs were valued as basic ingredients of incense, embalming preservatives, ointments, perfumes, antidotes against poisons, cosmetics and medicines and were used less in culinary preparations. A notable use of spices and herbs in ancient and medieval times were for the treatment of a variety of illnesses. Subsequently spices and herbs had come to be used to flavour food and beverages. In the course of time spices and herbs were shown to be useful not only for making the food lasting and palatable, but also in retarding or preventing rancidity and spoilage. This knowledge acted as a catalyst for the use of spices in a variety of processed foods. Based on the uses, herbs and spices are classified in to culinary, cosmetic and pharmaceutical. In the modern world spices have wide affiliation in the culinary art of people around the world, and are used in food industry for flavouring and seasoning, as well as in pharmaceutical preparations in the traditional systems of medicine and in beauty care. Spices and herbs are useful because of the chemical constituents contained in the form of essential oil, oleoresin, oleogum and resins, which impart flavour, pungency and colour to prepared dishes.

At present, approximately 1.4 million of the world’s species are described, but  majority are still unknown to science. Plant genetic resources have gained global attention in  recent past by agricultural and environmental institutions. Conservation and use of genetic resources attracted considerable attention. Value of biological diversity in economic terms is very important for human society. India is one of the major centers of diversity in world. A small part of plant and their culture is considered as floriculture. India is bestowed with varied types of agro-climatic conditions conductive for growing a wide variety of ornamentals including flowers. India has a rich heritage of ornamental floriculture.

In rural and hilly areas there are different types of colourful flowers and foliage at different seasons round the year. All these colourful flowers and foliage are wasted under natural process. In spite of aesthetic beauty, all these natural resources are totally unutilized due to unawareness of their use. All these flowers are available in wide range of colours but mostly dominated by yellow. The entire seasonal colourful vegetations can be converted into value added products by using simple dehydration technique developed at National Botanical Research Institute, Lucknow. The technique is  suitable for dehydration of flowers and foliage. Present chapter will highlight how dehydration techniques can be utilized for preparation of value added products from seasonal unutilized floral vegetation of rural India.

Exacum bicolor, Roxb. commonly known as country kreat is  endemic to Peninsular India. It is a herbaceous perennial with attractive flowers and posseses medicinal properties. Plant is endangered today due to large scale habitat destruction.  Non- lodging nature of plant, attractive bi-colored flower bunches with a long flowering period and good field life offer great future for this plant to be domesticated as an attractive garden flower. Its ornamental value and medicinal properties are yet to be fully exploited.

India is bestowed with a wide array of flowering plants. It represents two of the 18 hotspots of biodiversity in the world; one being the Western ghats and other the North Eastern Himalayas. Nature has also blessed our India with  uniqueness of endemism. Of the 17000 flowering herbs distributed in nine phyto geographical regions of the country, 5700 are endemic. Exacum  bicolor Roxb. is one of the endemic species to Peninsular India. Plant is popularly known as Bharachirata and Habshi chirata in Hindi, Kannamthali in Malayalam, Dodda  chirayuta in Kannada and ceti in Tamil.

Barleria L. (Acanthaceae) is a pantropical genus of herbs and shrubs comprising about 300 species, occurring mainly in Africa and Asia. In India, the genus is represented by about 32 species of which 24 are endemic to India.  About 80 % of the species are found in Peninsular India. Many species of Barleria are of ornamental value and can be grown for their foliage and showy colorful flowers. There are certain indigenous species which show good growth performance in cultivation and have economic importance as ornamentals. Moreover, some species fall under IUCN categories of threatened plants which need immediate attention for their conservation. Considering the horticultural importance especially in landscape gardening and rarity of Barlerias, various species found in India are collected and cultivated through various methods in the Botanical Garden of Shivaji University, Kolhapur.

India is one of the 17 mega biodiversity hot spot of the world contributing to the worlds largest plant resource,from the long stretches of the Eastern Ghats on the east, the greater Himalayan range on the northern planes and Western Ghats on the west. The Eastern Ghats range is unique on its own way to host many valuable flora from time immemorial. The Eastern Ghats are spread over four states from the north east to south east. Among the four states Orissa is one of them consisting of diversified floral resource.

Orchids, more than any other plants, exert a mysterious fascination for most people. All the wild Orchids of tropical regions are highly puzzling and peculiar. These largest spectacular plants of monocot belongs to family Orchidaceae  consisting of more than 17,000 known wild species including 750 genera in the world and the present figure of hybrids among these touches around 80,000 (Rao, T.A., 1998). This family is cosmopolitan in nature having more species in tropics than the temperate regions. This family of monocotyledonous plants has evolved from prototypes of the lily and amaryllis family and is note worthy for the wide variety of its highly specialized and curiously modified forms.

In literal sense a species is called underutilized whose potential has not been properly realized. These underutilized crops (referred to also by other terms such as minor, orphan, neglected, underutilized, underexploited, underdeveloped, lost, new, novel, promising, alternative, local, traditional, niche crops) have been included in world-wide plans of action after having successfully raised the interest of decision makers. Wealth of plant genetic diversity currently available holds vast potential. We use only small number of crop plants for our basic requirements. Many thousands of wild plants have great economic and cultural importance and tremendous market potential for vast numbers of people throughout the world. But the majority are still unknown to science. Plant genetic resources have gained global attention in  recent past by agricultural and environmental institutions. Conservation and use of genetic resources attracted  considerable attention. Value of biological diversity in economic terms is very important for human society.

The Indian region is one of the world’s eight centres of crop plant origin and diversity, distinguished by Russian Scientist N.I. Vavilov. The region is home to a rich endemic assemblage of plants. Scrub jungles, grasslands, dry and moist deciduous forests, semi-evergreen and evergreen forests are the variety of vegetations along the Ghats. The complex terrain and heavy rainfall have helped to preserve flora and fauna in this region. The Western Ghats are an area of exceptional biological diversity and conservation interest, and are “one of the major Tropical Evergreen Forest Regions in India”.  This region is extremely rich in floristic diversity and most of the species are not exploited so far. There are many underutilized endemic flowering plants found in Western Ghats having ornamental value. 

Flora of Western Ghats
 The Western Ghats cover only 5% of India’s total geographical area but contains more than 27% (4000 species) of  country’s total plant species (Nayar, 1996). The Western Ghats, also known as the Sahyadris, extend about 1600 km. starting in North from Tapti river and going down to Kannyakumari in the South. These ranges run parallel to West coast hardly 40 kilometres away on an average from shoreline. The Western Ghats run through states of Maharastra, Goa, Karnataka, Tamilnadu and Kerala. Elevation of Western Ghats is in  900 – 1500 m and in some places goes beyond 2000 m. The Western Ghats form major watershed in Peninsular India and  58 major Peninsular Indian rivers originate from them.

Yam bean(Pachyrrhizus erosus), a leguminous crop, native of North America is cultivated for its edible tubers. Though six species of Pachyrrhizus are grown for tuberous roots, P. erosus, P. tuberosus and P. aphipa are important.

While P. erosus(L.) Urban(2n = 22) has pods of 7.5-13 cm long, P. tuberosus has longer pods of 13-30 cm. P. aphipa is a non climbing plant with fusiform tubers and this species is mainly cultivated in Bolivia.  Synonyms for P. erosus are P. angulatus, P. bulbosus and Dolichus erosus.  P. erosus is the species commercially cultivated in India.

Wild forms of yam bean are seen in Mexico and northern parts of Central America, where its cultivation is reported during pre-Coloumbus period.  Yam bean is believed to have spread from Mexico to Philippines, Amboina before 17th century.  Now, yam bean is cultivated in China, Thailand, Singapore, India and Hawaii.

In India, it is grown in Bihar, West Bengal and Orissa.  In Hindi, it is called as “Miskri kand” and in Bihar as “Kesaru”.

Edible legumes are excellent sources of dietary protein and oils. Winged bean, otherwise known as Goa bean, Manila bean, princess pea, asparagus pea or four angled bean is becoming popular as a tropical legume vegetable. It is a multivitamin and multimineral packed legume. This wonder vegetable was considered as the vegetable of the twentieth century. It is also known as ‘soya’s rival’ or ‘God sent vegetable’. All parts of the plant are edible namely leaves, flowers, immature pods, immature seeds, mature seeds and tubers. It is also named as ‘a supermarket on a stalk’ because the plant combines the desirable characteristics of common bean, pea, spinach, mushroom, soya bean and potato. Its vernacular names are:  Bengali, Chara-koni-sem or lakar-sem; Tamil, Morisuavarai; Kannada, Shambe kayi; Malayalam, Chaturapayar or irachipayar and Marathi, Chavdhari ghevda.

Lesser yam, Lesser Asiaticyam (Dioscorea esculenta) is among the most ancient species of the genus and its centre of origin is stated by various authorities as India, Vietnam or Papua New Guinea and the Philippines. It is domesticated as a staple food in Southern China from 2nd and 3rd centuries. Today, it is widely distributed throughout the tropics, but is little used except in South East Asia, where it is grown to such an extent that it ranks third in production and utilization of yams after D. rotundata,D. cayenensis and D. alata. Wild types of D. esculenta also exist in Malaysia, New Guinea and Philippines.  The wild types have more leaves, large roots, longer stolons, more fibrous tuber flesh and more thorny roots and shoots.

Classification
The wild types of D. esculenta (Family: Dioscoreaceae) exist in Malaysia, New guinea and Philippines. Wild types have more vigorous foliage, larger leaves, longer stolons, more fibrous tuber flesh and more thorny roots and shoots.  On the basis of thorniness, the cultivated types are distinguished into two botanical varieties.

Dioscorea alata is commonly called greater yam or larger yam or water yam.  This is the most widely distributed species of yam. This species originated in South East Asia, probably in Burma. From there, it first spread to India, Malaysia, Indonesia and the eastern portion of South East Asia.  Later it served as food for voyagers and thereby spread to other parts of the tropics.  Immigrants from India and Malaysia introduced it to Madagascar, from where it was partially introduced into East Africa and Portuguese and Spanish voyager traders of the 16th century probably introduced it into West Africa and later to West Indies.

Coleus, commonly known as Chinese potato, is a minor tuber crop of the tropical regions of India, Indonesia, Malaysia, Sri Lanka and Africa. It is considered as a native of India , where its cultivation is mostly confined to the southern states. In Kerala, it is commonly known as koorka or cheevakizhangu. In Malaysia it is called ubi kemili, kentang kechil, kembili and kumbili java. It is also known as hausa potato, Sudan-potato, country potato, fra-fra potato, fra-fra-salanga, ratala, pomme de terre du Soudan, hausakartoffel, innala, saluga, tumuku and fabirama. 

Nutritive status
The nutritive status of this crop compares favourably with many of the major tuber crops.  Coleus tuber, with its characteristic  flavour has a special preference among consumers. Compared to other tuber crops, it fetches premium price in the market, although it is known as poor man’s potato. The tubers are used for the preparation of various delicious side dishes. Reliable data on area and production of this crop are not available. Despite the high market price and consumer preference, it is not available throughout the year.

The term arrowroot is commonly applied to many starch producing plants belonging to different species whose economic part is the rhizome, eaten fresh or made into flour. The term applies both to flour and the plant. All the plants of the arrowroot group have underground rhizomes or tubers from which arise reed like erect stems. The word ‘arrowroot’ is derived from the pointed shape of the rhizome or its known ability to cure arrow injuries. The word itself is derived from the carib word araruta meaning mealy roots. The arawak, a people native to the Caribbean islands, considered arrowroot a dietary staple. They called it aru-aru meaning meal of meals.

Tripura is situated between 22º 56’to 240 32’ N latitude and 91010’ to 92021’E longitude with tropic of cancer passing through it. The total geographical area of state is about 10,491 km2 of which 57.98 % area is under forest cover.  Agriculture is an important sector in the state, which contributes 26 % of the State GDP of which the major contribution is from horticultural crops like fruits (pineapple, litchi and oranges), vegetables (potato TPS), plantation crops (cashew nut, coconut, rubber and tea) and spices (ginger, turmeric and black pepper). More than 75 % of the population either directly or indirectly depends on agriculture. The small and marginal farmers constitute about 90 % of total farming community and the average size of land holding is 0.97 ha (1990-91) in comparison to 1.25 ha (1976-77), which is the lowest among the seven other North Eastern states.

Introduction

Plantation crops are high value commercial crops which are broadly classified as estate crops consisting of crops like tea, coffee and rubber and small holders plantation crops like coconut, cashew, arecanut, cocoa etc. Spices especially black pepper, cardamom, vanilla, tree spices like clove, nutmeg, cinnamon and allspice are generally grown as mixed crops in perennial cropping systems. In India, plantation crops including spices are grown in an area of three million hectares and generate an annual income of more than Rs, 5,53,630 million. They are valued for multifarious uses to meet the human needs such as food, oil, industrial raw materials, beverages and confectionary items. Pests and diseases are the major limiting factors in increasing the productivity of these crops. Among the pests, nematodes have got a major role in devastating the pepper plantations by the involvement in slow wilt disease, nematode diseases of cardamom nurseries, root-knot nematode infestation in ginger, turmeric, clove, nutmeg, allspice, lesion nematode infestation in tea, coffee, etc.

Introduction

Biological control of plant pathogens is currently accepted as a key practice in sustainable agriculture. Plant parasitic nematodes and mycorrhizal fungi are commonly found inhabiting the same soil and colonizing roots of their host plants. These two groups of microorganisms exert a characteristics, but opposite effect on plant health. The potential role of mycorrhizal fungi as biocontrol agent for the control of nematode plant diseases has recently received considerable attention. The literature on the various aspects of VAM research such as interaction of VAM- mycorrhizal fungi with nematode pathogens (Sikora, 1995, Pinochet et al. 1996), biotechnology and future of VAM commercialization (Wood and Cumming, 1992) and trends in mycorrhizal research (Sahay et al. 1998) has been reviewed. The damage due to nematodes diseases is generally decreased in mycorrhizal fungi has shown an antagonistic influence on the population of plant parasitic nematodes (Nagesh et al. 1999, Kantharaju et al.

Protected Cultivation

Protected cultivation (PC) may be defined as the “modification of the natural environment to achieve optimum plant growth” (Singh, 2005). Modifications can be made to both the aerial and root environments to increase crop yields, extend the growing season and permit plant growth during periods of the year not commonly used to grow open field crops. PC may also indicate comprehensive systems of ‘Controlled Environmental Agriculture’ in which all the aspects of natural environment are modified for maximum plant growth and economic return.

Introduction

Nematodes are cosmopolitan and ubiquitous in occurrence. These have been reported in all kinds of ecological niche. Accordingly, different kinds of nematode fauna had evolved with distinct morphological features and physiological variability. However, development and perception keep changing with the ambient environment. Agriculture has progressed with leap and bounce as human being has managed this to its maximum utility. The fast changes in agriculture definitely influenced the ecological niche and affected the flora and fauna. Consequently, specific and unspecific kind of relation evolved between host and parasite. With the thumb rule of ecological balance or homeostasis. In the dynamic Mother Nature, multispecies heterogeneous complex is sustained and nature do not perpetuate homogeneity.

Introduction

Banana is the forth ranked agricultural crop in the world and first among fruits. A large number of pests and diseases threaten banana production. The major constraints in production are diseases and pests transmitted through the conventional planting materials. Although the average yield for bananas worldwide is over 40 t per hectare, production in India averages only 20 t per hectare. The nematode parasites are among the most important pests on commercial and subsistence banana production and their control remains difficult, as the nematodes are involved in the destruction of primary roots that disrupt the anchorage system resulting in toppling or uprooting of plants. The most widespread and important are burrowing nematode, Radopholus similes, some species of root lesion nematode, Pratylenchus coffeae and P. goodeyi, species of root knot nematode, Meloidogyne incognita and M. javanica; the spiral nematode, Helicotylenchus multicinctus, H. mucronatus and semi endo-parasitic nematode Rotytlenchus reniformis.

Introduction

Seed spices have prominent place in India’s national economy because of their very high domestic consumption and growing demand for export. This group of spices, being consisting of mostly annual crops, is grown extensively in rotation with food and cash crops and also as inter crops under rain fed as well as irrigated conditions.

There are about 20 seed spice crops grown in India. Out of which nine are important in terms of production and export. The most important ones are coriander, cumin, fennel and fenugreek (major seed spices) and ajowain, aniseed, black cumin, celery and dill (minor seed spice crops). Although these crops are grown all over India but Haryana, Rajasthan, Madhya Pradesh, Uttar Pradesh, Orissa, Tamil Nadu and Andhra Pradesh are the main seed spice growing states.

Introduction

Rice (Oryza sativa L.), one of the most important cereal crops of India, occupies 23.3 per cent of total cropped area of the country. Rice contributes 43 per cent of total food grain production and 46 per cent of total cereal production. It continues to play a vital role in the nation’s food grain supply. It is also a staple food of nearly half of the world population. Rice is primarily a high caloric food having protein content (6-17%) with high biological value and a low amount of fat (2-2.5%). B-group vitamins content in rice grains are at par with wheat, however, calcium content in rice is generally low. It ranks third after wheat and maize in terms of worldwide production. Asia accounts for 90 and 92% of the world’s rice area and production, respectively. Thus, rice production, consumption and trade are concentrated in Asia. Among the rice growing countries in the world, India has the largest areas under rice crop and ranks second in production next to China.

Introduction

Maize (Zea mays Linn) is the most widely distributed crop of the world. It adapts easily to a wide range of production environments and is grown in tropical, subtropical and temperate regions of the world. It holds a unique position in world agriculture ranking third after rice and wheat in terms of area as well as production. In India too, it is the third most important cereal crop and is cultivated in 8. 17 m ha (2007-08) area. It contributes nearly 8% to the national food basket and more than Rs 100 billion to agricultural gross domestic products with an annual production of 19. 73 million tons. It is used as a source of human food (24%) animal feed (11%), poultry feed (52%), starch (11%), brewery and seed (1% each). In India it is largely grown in Northern states where it serves as an important staple food for an economically vulnerable population of submountainarean and hilly regions.

Introduction

Plant paprasitic nematodes are one of the limiting factors in the production of horticultural crops in the country. The visible symptoms of nematode attack are: Reduced individual plant growth, varying degrees of chlorosis, wilting of the foliage and sometimes death of the plants.

The roots, damaged by nematodes are not efficient in the utilization of available moisture and nutrients in soil resulting in reduced functional metabolism. Nematode infested roots are easily infected by various pathogenic fungi and bacteria and aggrevate root damage. These deleterious effects on plant growth result in reduced yield and poor quality of crops as in citrus, banana, grapevine, pineapple, papaya and vegetable crops. Decline or death of highly prised ornamentals and turf is often the result of nematode infestation.

Introduction

India has the distinction of being the largest producer of pulses in the world. Among the important pulse crops cultivated in the country are: chickpea, pigeonpea, lentil, mungbean, urdbean, fieldpea, rajmash and lathyrus. The pulse crops occupied an area of 22.85 million ha with a total production of 13.07 million tones and average productivity of 572 kg/ha. Being a high protein grain, pulses have special status in the diet, particularly for vegetarian population. Apart from being a good source of protein, they are also good source of energy, essential amino acids and vitamins in the daily diets of the people, especially of low-income group. Pulses have importance in sustainable agriculture by way of fixing atmospheric nitrogen in the soil.But with intensification of agriculture and introduction of irrigation and other facilities the area and production under pulses is declining so much so that per caput availability of pulses has declined from 69 g day-1 to about  36 g day^-1.

Preamble

In India, agriculture plays an important role as it accounts for about 18% of the GDP and supports nearly 58% of the total working population for employment. Food grain production increased significantly from a low level of 50 million Tons during 1950-51 to a record of 230.7 million Tons in 2007-08. The demand for food is growing rapidly due to increasing population and rising income levels, hence we need to produce about 320 million Tons of foodgrains by the year 2025. It implies more pressure on our exhisting land, soil and water resources which are already in short supply, degraded, fragile and this similar situation is being faced by mainly developing countries today. Plant parasitic nematodes are of great economic significance. Since most of them live in the soil hence represent one of the most difficult pest problems in terms of identification, demonstration and management.