eChapters

6.1 Introduction

Scientists and engineers have an experimental data of various variables in an experiment. To know the facts and to formulate related theories, they need exact relationship between such variables. So, they require the exact function which defines the outputs with introducing the inputs. For example,

Ohm’s law: which states that voltage of a circuit is proportional to the current flowing in it i.e.

7.1 Introduction

A Scottish mathematician David Gibb was firstly introduced a term ‘Numerical Integration’ in 1915. Like numerical differentiation, numerical integration is also a very useful tool for scientists and engineers especially when they have an experimental data for different variables without knowing any mathematical relationship between them. Beside it, there are also many other situations where it plays an important role for integrating the functions like:

8.1 Introduction

In the fields like Physics, Chemistry, Biology, Engineering and Economics; their laws and principles contains various parameters and their derivatives. The mathematical relationships of such parameters with their derivatives constitute the differential equations. In calculus, differential equations were firstly introduced by Newton and Leibnitz. Newton listed the three kinds of differential equations:

Stem cell research is one of the most important and promising areas of research in biological science in recent times. The stem cell technology has revolutionized modern biology. It is playing a major role for improving human as well as animal health by controlling number of incurable degenerative diseases and restoration of damage to organs via transplantation therapy. Stem cells are a specific group of cells that remain in an undifferentiated state and can be found in embryos, fetuses and adult individuals. Stem cells are primitive, undifferentiated cells present in almost every tissue that have the ability to differentiate into different types of tissue like bone, tendon, ligament, cartilage etc. Bone marrow stem cell is the ideal stem cell that is unspecialized and can undergo lineage specific differentiation into bone or blood cells under different signals or environment with new special function. Several verities of stem cells have been isolated and identified in vivo and in vitro. The two broad types of mammalian stem cells are embryonic stem cells that are found in blastocyst, and adult stem cells that are found in adult tissue, bone marrow.

Mesenchymal stem cells are multipotential cells capable of proliferation and differentiation into osteogenic, chondrogenic and adipogenic lineages both in vitro and in vivo. Minimal criteria for defining MSC according to International Society of Cell Therapy (ISCT) are (a) they must be plastic-adherent when maintained in a standard culture conditions, (b) MSC must express some surface antigen such as CD105, CD73, CD90, CD44 and must not express CD34, CD45, CD 14, CD19, and HLA-DR, and (c) MSC must differentiate in vitro into osteoblast, adipocytes and chondrocytes under specific differentiating condition.

Although traditionally MSC isolated from bone marrow, more recent reports have detailed the isolation of cells with MSC characteristics from a variety of tissues including umbilical cord blood, chorionic villi of the placenta, Wharton’s jelly, peripheral blood, fetal liver and lung, adipose tissue, skeletal muscle, periosteum, deciduous teeth, amniotic fluid, dental pulp, testis, synovium and the circulatory system. Bone marrow and periosteum sources are richest in young animals with their numbers diminishing, but still present in old age. It is estimated that MSCs represent approximately only 0.01 to 0.001% of the total nucleated cells within isolated bone marrow aspirate. The yield of MSCs from bone marrow varies from species to species. e.g., Canine =1 in 2.5 × 10⁴; Feline =1 in 3.8 × 10⁵; Murine =1 in 10.8 ×10³ to 1 in 3.45×10⁴ and Horses =1 in 4.2 × 10³. Despite this low number, they are remains a great interest, as they can be easily isolated from a small aspirate and culture-expanded through as many as 40 population doublings to significant numbers in about 8 to 10 weeks.

Bone marrow contains variety of tissues including hematopoietic lineage cells and mesenchymal stem cells (MSCs). The hematopoietic cells are the major source of the blood cells in the adult body which are regulated within the microenvironment of the stromal cells of the bone marrow. MSCs are multipotent cells and can be differentiate into various cell lineage depend upon their environment and culture condition in which they are kept. Rat bone marrow derived stem cells (rBM-MSCs) have long term self renewing and capabilities of pluripotency including osteoblast, adipocytes, chondrocytes, tenocytes, muscle cells and neurogenic cells, which make them ideal source of stem cells for regeneration of injured tissue.

Bone marrow derived mesenchymal stem cells have been isolated from different species. Each species is having different culturing and growing capacity. For example human bone marrow derived stem cells are easy to harvest and maintain in culture condition whereas rat MSCs it is more difficult compared to other species. Technical difficulties in isolation limited the number of animal experiment and its required animal transplantation model for pre clinical studies. Density gradient centrifugation, plastic adherence and immunomagnetic selection like various methods are available for isolation of MSCs from bone marrow. No appropriate methods are available for selection of suitable cells. Each method has their own pros and cons. Therefore, in this chapter, combined density gradient centrifugation and plastic adherence as easy and reliable method for isolation, culture and characterization of rat bone marrow derived mesenchymal stem cell is described.

Mesenchymal stem cells are multipotential cells capable of proliferation and differentiation into chondrogenic, osteogenic and adipogenic lineages. Minimal criteria for defining MSC according to International Society of Cell Therapy (ISCT) are (a) they must be plastic-adherent when maintained in standard culture conditions, (b) MSC must express some surface antigens such asCD105, CD73, CD90, CD44 and must not express CD34, CD45, CD 14, CD19, and HLA-DR, and (c) MSC must differentiate in vitro into osteoblast, adipocytes and chondrocytes under specific differentiating condition. 
Although MSC is traditionally isolated from bone marrow, more recent reports have detailed the isolation of cells with MSC characteristics from a variety of tissues including umbilical cord blood, chorionic villi of the placenta, Wharton’s jelly, peripheral blood, fetal liver and lung, adipose tissue, skeletal muscle, periosteum, deciduous teeth, amniotic fluid and synovium. Bone marrow and periosteum sources are richest in young animals with their numbers diminishing, but still present in old age. One of the attractive advantage of bone marrow derived mesenchymal stem cells (BM-MSCs) as a source of cell transplantation is their low immunogenecity. Recently, several studies have reported that BM-MSCs may be immune-privileged cells that do not elicit immune response due to an absence of their immunologically relevant cell surface markers. BM-MSCs also are known to inhibit proliferation of T lymphocytes, B lymphocytes, dendritic cells and natural killer cells.

The knowledge and principles from interconnected disciplines of bioengineering, material science and life sciences are combined in tissue engineering with the aim of developing a construct that can wholly or partly restore/maintain/augment the function of a damaged tissue or organ. Tissue engineering construct generally comprises cells on a suitable scaffold. The ultimate functionality of a tissue engineering construct is mainly dependent on the cell behavior on scaffolds. The proliferation and cell viability on scaffolds varies from one cell type to another and from one species to another. So it is important to investigate individual cell-scaffold combinations.

The similarity in structure and composition to bone mineral, osteoconductive properties, ability to integrate with the bony tissue and absence of immune response makes hydroxyapatite [Ca10 (PO4)6(OH)2] the choice of calcium phosphate biomaterial with only disadvantage of slow rate of resorption. On contrary, silica–calcium phosphate composite in comparison to calcium phosphate is rich biomaterials having a faster resorption rate. Studies have shown that coating of hydroxyapatite with a calcium silicate containing layer encourages cell proliferation and osteogenic differentiation of human bone marrow-derived stromal cells.

In this chapter a composite scaffold (calcium silicate, hydroxyapatite and tricalcium phosphate), namely HASi with elements in the following percentages: 66.36 % - calcium, 25.35 % - phosphorus and silicon - 8.29 % and porosity of 50 – 500 µm is undertaken to evaluate the rBMSC proliferation and differentiation properties in vitro with the aim of assessing cytocompatibility of HASi and rBMSC in terms of cell attachment, cell morphology, cell proliferation and osteogenic differentiation.

Fracture healing is a complex process in which damaged bone restores its original architecture through a cascade of molecular and cellular events. The process of fracture healing is unique, in that it does not form a poorly organized replacement matrix, otherwise known as scar tissue, but rather regenerates the original matrix and retains its mechanical properties. Normal fracture and bone repair follows a known sequence of events includes: haematoma formation, inflammation, angiogenesis, osteogenesis, and bone remodeling.

For the repair of bone defects, a tissue engineering approach would be to combine cells capable of osteogenic (i.e. bone-forming) activity with an appropriate scaffolding material to stimulate bone regeneration and repair. An ideal tissue-engineered bone substitute should possess 3 elements: osteoprogenitor cells, osteoinductive factors, and an osteoconductive scaffold, and is considered as a potential substitute for autologous bone transplantation. Tissue engineering approaches have proven very effective in bone regeneration recently, and the successful repair of bone defects has been demonstrated in larger animals like canine, goat and sheep.

Stem cells from adult tissues are attractive materials for cell therapy, gene therapy, and tissue engineering. These cells generally have restricted lineage potential when compared to embryonic stem cells, and this may be advantageous in certain therapeutic applications. Till and McCulloch in 1961 describes the presence of hematopoietic progenitor cells in bone marrow. After this, the concept of MSCs is brought to light by Friedenstein and co-workers who demonstrated the osteogenic potential of BM cells by heterotrophic transplantation.

Despite the benefits that minimally invasive surgery and osteosynthesis have brought to fracture management and bone healing, there are still many circumstances where bone healing remains challenging. Large bone defects are serious complications that are most commonly caused by extensive trauma, tumour, infection, or congenital musculoskeletal disorders. In nonunion cases repairing of bone defects with composite biomaterials as defect filler can promote bone regeneration. Currently, the gold standard for bone regeneration is use of autogenous bone graft. In order to avoid morbidity at the donor site or if large amount of autogenous bone is needed, bone substitution materials can be used.

Bone substitution materials can be combined with cells such as mesenchymal stem cells (MSCs) to increase bone formation. Bone-marrow derived mesenchymal stem cells (BMSCs) represent an attractive cell population for tissue regeneration. Bone marrow stem cells are pluripotent cells that have been used to facilitate bone repair because of their capability of differentiating into osteoblasts. Several studies on the regeneration of bone have shown that cultured BMSCs, seeded on different bioabsorbable implants are able to induce bone formation in vivo and lead to improved healing of critical-size defects.

Disruption of the cellular or anatomical continuity of the normal organ structure is known as wound. Healing involves migration, infiltration, proliferation and differentiation of several cell types like keratinocytes, fibroblasts, endothelial cells, macrophages, and platelets which are culminate as an inflammatory response, new tissue formation and wound closure. Healing of the wound starts from the moment of the injury and can continue for varying periods of time depending on the extent of wound. The process of wound healing involves coagulation, inflammation, formation of granulation tissue, matrix formation, remodeling of connective tissue, collagenization and acquisition of wound strength.

Chitosan is a -1, 4-linked polymer of glucosamine (2-amino-2-deoxy—D-glucose) and lesser amounts of N-acetylglucosamine. It is a derivative of chitin (poly-Nacetylglucosamine) which is the second most abundant biopolymer after cellulose. Chitosan is first discovered in 1811 by Henri Braconnota, a French chemist and pharmacist. Later in the century, chitin is found in crustaceans (such as crabs, lobsters, shellfish and shrimp). Chitosan is a biodegradable polymer and it accelerates wound healing. It has been reported that chitosan permits regeneration of tissue elements in skin wounds and has positive application effects on wound healing.

The cornea is the anterior transparent part of the fibrous tunic of the globe which has both mechanical and optical function. It functions to support the intraocular contents and transmit and refract light. Histologically, the cornea is composed of an outer stratified squamous corneal epithelium and its basement membrane, an underlying collagenous stroma, a thin acellular membrane, and an inner monolayer of cells, the corneal endothelium. In dogs, the central cornea is thinner than the peripheral cornea, whereas regional differences in thickness may not exist in cats. The active pumping mechanism of corneal endothelium and the barrier function of anterior epithelium keep the cornea in a state of relative dehydration. Compromise of either of these mechanisms will allow corneal edema to develop, with a concomitant increase in corneal thickness. Corneal ulceration is one of the most common ophthalmic disorders in veterinary medicine. Corneal ulcers are classified based on depth and ease of healing. There are several phases during the corneal epithelial wound healing process, including a lag phase where cells alter their metabolic status; a migration phase to cover the bare surface; a proliferation phase and a differentiation phase, where cells stratify and re-establish multiple layers of distinct cells. Methods of surgical treatment for canine corneal ulcers include temporary tarsorrhaphy, third eyelid flap, conjunctival pedicle graft, tissue adhesive, corneo-scleral graft and transplantation of natural or synthetic material.

Full thickness burn wound will not heal spontaneously which need early excision and adequate coverage to prevent fluid loss and risk of infection. Major portion of the skin is lost during burn injury which is the active layer for protecting the entry of micro organism from outside environment. So far, meshed autologous skin graft is regarded as the gold standard for treating extensive full thickness burns. However, their frequent use may be hampered by several impediments such as limited availability, donor site morbidity, associated with additional scarring. Severe burn patients invariably lack additional skin donor site. Moreover, creation of donor site in burned patient is equivalent to second degree burn and which further increase the total body surface area affected (TBSA). In past decades, numerous biomaterials have been investigated for the use as a dermal skin substitute for burn patients but none give promising results. The innovative tissue engineered bioactive materials offer potential tissue regeneration and prevent the tissue deterioration.

The extracellular matrix (ECM) derived naturally from mammalian tissue have been successfully used as scaffold for tissue reconstruction and wound management in clinical applications. ECM can be derived from various tissue or organs of different species but most commonly, porcine small intestinal submucosa and urinary bladder have been successfully used as scaffold for reconstruction. ECM is obtained by process of decellularization that involves the use of various ionic and non ionic detergents, acids, enzymatic solutions and mechanical/physical methods.

Burn wounds are considered to be one of the most devastating kinds of trauma that affect the physical, physiological and psychological well being of an individual. Based on the depth of the affected area, burn wound is divided into three categories: first degree (superficial), second degree (partial) and third degree (full thickness). Extensive and deep burns result in scar formation and subsequent deformation of the affected part. Healing of burn wound involves several interrelated and overlapping stages such as inflammatory, proliferative and remodeling phases. The interaction of a variety of mediators, cells and extracellular matrix proteins are involved in this three phases of healing.

Burn wound therapy has been performed in various ways such as bioengineered skin grafts and administration of growth factors. Small intestinal sub-mucosa (SIS) is a resorbable xenogenic bioscaffold that has induced constructive remodeling in variety of animal models. It is unique from other acellular matrices as it contains few growth factors such as fibroblast growth factor (FGF) and transforming growth factor (TGF) that play a role in the regenerative process. Chitosan is currently proposed to be one of the most promising polymers in wound dressing development and it accelerates wound healing. Epidermal growth factor is known to stimulate growth of keratinocytes in vitro, thus it might be expected to promote wound healing.

In this chapter efficacy of Chitosan and porcine acellular small intestinal sub-mucosal (SIS) matrix seeded with bone marrow derived mesenchymal stem cells (BM-MSCs) and recombinant murine epidermal growth factor (m-EGF) on healing of full thickness burn wound in rat model is described.

The liver is an organ that plays a central role in maintaining metabolic homeostasis, in its functions of metabolism, synthesis and storage of nutrients. The cells in the liver are parenchyma cells and non- parenchyma cells. The former include hepatocytes (80% of the cell population) and the later includes endothelial cells, Kupffer cells, lymphocytes and stellate cells. Liver dysfunction or failures are having different etiologies. Liver cancer has the fifth highest cancer incidence in the world, and is the third highest cause of cancer related deaths, with resection of the liver remaining the only curative option.

Following liver injury, the repair process involves two distinct phases: a regenerative phase, in which injured liver cells are replaced with regenerated hepatocytes; and a phase known as fibroplasia or fibrosis, in which connective tissue replace normal parenchyma tissue. The process even though initially beneficial becomes pathogenic when it is not controlled appropriately. Extensive accumulation of extra-cellular matrix (ECM) components ultimately leads to cirrhosis and liver failure. Thus, the ideal strategy to treat liver injury is to generate new hepatocytes replacing damaged cells without causing excessive ECM deposition.

Bone is the only tissue in the body able to heal without microscopical scarring. On the other hand fracture healing is a slow process causing long immobilization periods with consequently high costs for fracture healing giving rise to delayed healing, fibrous healing or non-healing with subsequent problems for both, the patient and the orthopedic surgeon. Fracture healing is complex phenomenon which involves numerous cells, regulators of cell function and biochemical interactions in the repair process. The healing potential of bone, in a fracture model is influenced by a variety of biochemical, biomechanical, cellular, hormonal and pathological mechanisms. A continuous occurring state of bone deposition, resorption and remodeling facilitates the healing process.

Biodegradable and bioinert ceramic materials such as hydroxyapatite (HA), tri­calcium phosphate (TCP), aluminum-calcium-phosphate (ALCAP) ceramics provides scaffold to support the attachment and migration of newly formed bone cells into the osseous defect and also help in formation of a vascular network through the newly formed bone. Bioceramic also act as a carrier to deliver stem cells for osteogenesis.

Specific bone-inductive proteins/growth factors can induce bone formation and healing in vivo. These morphogens are therefore, to be an ideal alternative to autogenous bone grafts. These findings initiating intensive research into bone regeneration orchestrated by putative soluble signals and lead to the discovery and identification of an entirely novel family of protein initiators collectively called the bone morphogenic protein (BMPs), which belong to transforming growth factors-ß (TGF- ß) super family. These growth factors might possess a biological activity that is site and tissue specific in the induction of bone formation. Different growth factors have been demonstrated to possess osteoinductive and fracture healing properties.

Collect the femur and tibia and clean them very well from blood, tendons, muscle, skin and other tissues (using scalpel)

Cut off epi-and metaphysis from the long bones with electric/manual bone saw
Transfer the open bones to a falcon tubes containing cell culture medium/DPBS without FBS but containing 1% PS (Penicillin-streptomycin)
Transfer the bones to a Petri dish containing 5 ml medium without serum (FBS) and without antibiotic (40-50 mm Petri dish)
Remove the pteri dish to the laminar cabinet
Collect the bone marrow by flushing out to a 50 ml falcon tube (use syringes and needles to flush out the bone marrow; flush out the bone marrow with complete (10% FBS, 1% PS, 90% DMEM-LG) culture medium
Centrifugation: 300rpm, 8 min (in the meanwhile prepare 5 ml of Ficoll into a 15ml falcon tube)
Aspire the medium

1.    Collect fat tissues from euthanized animals into a Falcon tube containing DPBS + 1% PS ( for transferring lab to lab)
2.    Wash 3 times with DPBS + 1% PS
3.    Inside a laminar cabinet, transfer the fat to a Petridis (use an sterile spatula to collect the fat)
4.    Cut the fat into small (mm) pieces using scalpel and forceps or scissors
5.    Transfer the fat into a Falcon tube (eg into a 50 ml Falcon tube you can add upto 10 ml fat tissues)
6.    Wash the fat by adding approx 40 ml DPBS; Centrifugation: 430g, 10 min (without break)
7.    Transfer the fat into a fresh 50 ml Falcon tube (with the help of sterile spatula); Repeat steps 5 to 7 for 2-3 times

1.    Collect the bone marrow from iliac crest of rabbit, dog, goat and sheep; sternum of pigs by 16-18 G bone marrow biopsy needle under sedation/anesthesia and maintain strict asepsis protocol
2.    To aspirate bone marrow, negative pressure should create in the syringe by pulling back the plunger. Syringe should be first flushed with heparin before bone marrow collection
3.    Collect approximately 2.5-5 ml of bone marrow from each animal
4.    Mix the bone marrow sample with equal volume of low DMEM having 10% FBS and 1 ml of PS and then layer on 5 ml of histopaque/Ficol-Paque Plus in a falcon tube
5.    Centrifuge at 3000 rpm for 30 min
6.    Collect stem cells from the interface with the help of a micropipette
7.    Cells wash thrice with DPBS 
8.    Centrifuged at 2000 rpm for 5 min

1.    Remove the growth media
2.    Wash 2 times with warm PBS (w/o Ca and Mg)
3.    Add 5ml of trypsin /EDTA 0.35 % (Invitrogen), place at 370C in a CO2 incubator for 4-5 min
4.    Wait until cells are detached/lifted and make sure by examining on microscope
5.    Add equal volume (5ml-1:1) of growth medium as appropriate and mix with 5 strokes
6.    Transfer into 15 ml centrifuge tube
7.    Centrifuge at room temperature for 4 min in 980 rpm
8.    Remove supernatant complete but carefully without touching the cell aliquot
9.    Re-suspend in 10ml DPBS (with Ca and Mg)-5 strokes
10.    Immediately after mixing transfer 100µl of cell suspension into Casy vial, containing 10ml Casyton

Downy mildew is refered to a condition of plant disease where the fungal growth and infection appears on the dorsal side of the leaf surface while the corresponding ventral side of the leaf shows faint yellowish color. It is also refered to the fungus which causes this disease.The word mildew in Latin language means mil + dew i.e honey like dews.The fungal growth on plant surface resembles to the milky dews in the beginging which turn to golden brownish honey like dews in later stage. Subsequently the affected areas turn grayish brown and dry. Besides the infection of leaves, the fungus also infects the fruits. The downy mildew infection on fruits causes the deformities on the affected fruits. The infection of the downy mildew pathogen on some of the cereals like pearlmillet causes the symptoms like green ear disease .

Downy mildew pathogens can cause major damage in the nursery, in greenhouse, in field crops and in landscape in the form of leaf spots, blights, and distortions with mildew growth. Downy mildews are primarily foliage blights with mildew growth of the fungus on affected portion. The fungus attack and spread rapidly in young, tender green leaf, twig, and fruit tissues. The fungal development are severe when a film of water is present on the plant tissues and the relative humidity in the air is high during cool or warm, but not hot, periods. Downy mildews can cause severe losses in short periods of time. Downy mildews often cause rapid and severe losses of young crop plants still in the seedbed or in the field. They often destroy from 40 to 90% of the young plants or young shoots in the field, causing heavy or total losses of crop yields. The severity of loss depends on the prolonged presence of wet, cool weather during which the downy mildews fungus sporulate profusely, cause numerous new infections, and spread into and rapidly kill young succulent tissues.

2.1. Downy mildew of Sorghum
Pathogen: Peronosclerospora sorghi (W. Weston & Uppal) C.G. Shaw, (1978)
Host plants
Major hosts: Sorghum bicolor (sorghum), Sorghum caffrorum, Sorghum Sudanese (sudan grass), Zea diploperennis, Zea mays. 
Minor hosts: Andropogon sorghi, Panicum trypheron, Pennisetum glaucum (pearl millet), Sorghum halepense (Johnson grass), Zea mexicana (teosinte) 
Geographic Distribution
It is found worldwide in tropical and subtropical regions. Sorghum downy mildew is widely distributed in following countries.
Asia: Bangladesh, China, India, Iran, Israel, Japan, Nepal, Pakistan, Philippines, Thailand and Yemen (CMI, 1988; Jeger et al., 1998).In India though the losses are reported from the states of U.P. and Madhya Pradesh, the disease is very common and destructive in Karnataka, Tamil Nadu, Andhra Pradesh, and Maharashtra

3.1. Downy mildew of peas
It is an important disease of pea crop particularly in those areas where cool and wet climate is prevalent during its cultivation. The disease during favourable weather conditions causes considerable yield losses.
Pathogen: Peronospora viciae (formerly P. pisi)
Host range
Vigna faba, Vigna sativa. Pisum arvensis, P.sativum, Lathyrus sativus, Vicia hirsuta, Vicia sativa, Vicia villosa (Dixon, 1981).
Geographical distribution
Reports of the pathogen are from different countries on different crop host.
On Pea- Berkeley in England first discovered the disease in 1846 (Chupp and Sherf, 1960) and since then it has been found in all parts of the world where the crop is grown intensively. The occurrence of the disease has been reported from Argentina, Australia, Canada, Chile, Denmark, France, Germany, Kenya, Netherland, New Zealand, Rhodesia, Spain, Tasmania, USA, Ukrain, Italy, Poland and Australia (Dixon,1981). In India it is prevalent in Indogangetic plains including Uttar Pradesh and Punjab (Bains and Dhaliwal, 1986).

4.1. Downy mildew of sunflower

Pathogen: Plasmopara halstedii (Fort.) Berl.& de Tom.

Hosts

Over 100 host species from a wide range of genera in the family Asteraceae have been reported susceptible to this pathogen, including wild and cultivated species of Helianthus, e.g. sunflowers, which is the principal economic host. Wild Asteraceae hosts (e.g. species of the genera Helianthus, Artemisia, Xanthium, etc.) may also occur widely in the corresponding areas but their potential as reservoirs of the pest is not yet known (Virányi, 1984). For lists of hosts see Leppik (1966) and Novotel’nova (1966).

Geographical distribution

EPPO region: Present wherever sunflowers are grown, in Albania, Austria, Bulgaria, Czech Republic, Egypt, Estonia, France, Germany, Hungary, Italy, Moldova, Morocco, Poland (unconfirmed), Romania, Slovakia, Spain, Switzerland, Turkey, Russia (European, Siberia), Ukraine and Yugoslavia.
Asia: Azerbaijan, China, Georgia, India, Iran, Iraq, Israel, Japan, Kazakhstan, Pakistan, Russia (Siberia), Turkey. 
Africa: Egypt, Ethiopia, Kenya, Morocco, Zimbabwe, Uganda.

5.1 Downy Mildew of hemp

Pathogen: Pseudoperonospora cannabina

Geographical distribution
 
It’s spread has been limited to Asia and Europe.

Symptoms

Downy mildew begins as yellow leaf spots of irregular size and angular shape, limited by leaf veins. Opposite the spots, on the underside of leaves, the fungus emerges from stomata to sporulate. Mycelial growth on the underside of leaves is best seen in early morning when dew turns the mycelium a lustrous violet-grey colour (Fig 5.1). Lesions enlarge quickly and affected leaves become contorted. Leaves soon become necrotic and fall off. Whole plants and entire fields may follow this pattern.

6.1. Downy mildew of Sugarcane

Pathogen: Sugarcane downy mildew can be caused by four species:

    1)    Peronosclerospora sacchari
    2)    P. miscanthi
    3)    P. spontanea and
    4)    P. philippinensis

Major Host
Hosts in the Saccharum genus include: S. officinarum, S. robustum, S. spontaneum and S. edule.

Minor Host
Other hosts include Zea mays (maize), teosinte (Euchlaena mexicana), Sorghum halapense (Johnson grass), S. sudanense (Sudan grass), Tripsacum dactyloides (Gama grass), Sorghum bicolor (broom corn). Other studies suggest there are 18 species that are systemically infected in the sub-family Panicoideae; these include species of Andropogon, Bothriochloa, Eulalia, Schizachyrium and Sorghum (Bonde & Peterson 1981)

Geographic Distribution
The disease is restricted to the Pacific, South Asia and South East Asian regions viz Fiji, India, Indonesia, Japan, Papua New Guinea, Philippines, Taiwan and Thailand (Suma & Magarey 2000).

7.1 Downy mildew of grape
Pathogen: Plasmopara viticola

History and Epidemics
In France downy mildew is called as “le mildiou” while in Germany it is called as “falscher Meltau”. Downy mildew is undoubtedly of American origin and was probably indigenous on the wild grapes of the eastern United States, from which it spread to the cultivated vineyards when these were established by the colonists. It was not known to occur outside America until 1870, although it was first described from this country as early as 1834. In the early part of the last century various horticultural writers referred to the destructive action of the mildew on cultivated grapes.
Its history in Europe dates back to the time when French vine-yards were suffering from the grape Phylloxera, an aphid insect pest that was also introduced into Europe from America. It was found that rootstocks of the American species were more resistant to this aphid than was the European vinifera grape, and therefore consequently around 1870 importations of the American Vines were made into Europe, and somewhere around 1875 the downy mildew fungus evidently was also introduced with these importation and became established, and by 1878 it was prevalent enough to cause alarm. Since the European vinifera grapes were far more susceptible to this disease than were the American species, it soon became a real menace to grape culture throughout the humid sections of Europe.

8.1. Downy mildew of cruciferous vegetables

Cruciferous vegetables are important Kharif vegetable crops, which are grown both for table and seed purpose. This vegetable group constitutes crops like cauliflower, cabbage, radish, turnip, broccoli, brussel’s sprouts; knol-khol and rutabaga .The vegetable crops affected by downy mildews pathogen Peronospora parasitica are members of the genus Brassica and the downy mildew diseases on these crops are widespread in those regions of the world, which have cool and wet climate.

Geographical distribution

The downy mildew disease on cruciferous crops has worldwide distribution. The disease was first recorded in 1883 in USA on Brassica spp. (Farlow, 1883). In India, this disease was first reported by Butler in 1918. Subsequently various authors reported this disease from many countries of the world (Channon, 1981) particularly Angola (Serafim and Serafim, 1968), Argentine (Lindquist, 1939), Australia (Samuel, 1925; Anon., 1955), Austria (Glaeser, 1970), Bermuda (Waters-ton, 1940), Brazil (Grillo, 1937), Britain (Moore, 1959), Brunei (Herb. IMI), Canada (Jones, 1944; Downey and Bolton, 1961), Chile (Mujica and Vergara, 1960), China (Porter, 1926; Pai, 1957), Columbia (Orjuela, 1965), Costa Rica (McGuire and Crandall, 1967), Cuba (Fernandez Rosenada, 1973), Cyprus (Herb.IMI), Czechoslovakia (Rydl, 1968), Denmark (Gram and Rostrup, 1924), Dominica (Anon., 1972a), Egypt (Elarosi and Assawah, 1959), Ethiopia (Herb. IMI), Fiji (Anon, 1969), Finland (Herb. IMI), France (Darpoux, 1945), Germany (Neumann, 1955), Greece (Herb.IMI), Guatemala (Muller, 1950), Haiti (Anon., 1972a), Hong-Kong (Johnston, 1963), India (Thind, 1942), Iran (Ershad, 1977), Iraq (Herb.IMI), Israel (Peleg, 1953), Italy (Ciferri, 1961), Jamaica (Leather, 1967), Japan (Hiura and Kanegae, 1934), Kampuchea (Soonthronpoct, 1969), Kenya (Anon., 1957), Korea (Anon., 1972b), Libya (Herb.IMI), Malawi (Peregrine and Siddiqi, 1972), Malaysia (Mcintosh, 1951), Malta (Herb.IMI), Mauritius (Orian, 1951), Mexico (Rodriguez, 1972), Morocco (Herb. IMI) , Mozambique (Decarvalho, 1948), Nepal (Bhatt, 1966), Netherlands (Thung, 1926b), New Zealand

9.1. Downy mildew of Opium poppy
Pathogen: Peronospora arborescens (Berk) de Bary

Geographical distribution and losses
This is one of the serious and widespread diseases of opium poppy. The disease was observed epiphytotic in Argentina, Germany, Iran, Hungary, Austria and India. The disease was first recorded in India in 1918 and with the introduction of susceptible varieties, the disease rapidly became serious due to favourable environment in its cultivation area in India. Downy mildew now occurs in most regions in India (Rajasthan, Madhya Padesh and Uttar Pradesh). Downy mildew caused 20-30% loss of yield of opium latex. The secondary infection of downy mildew was found to reduce 11-22% latex.

Symptoms
The infection spread upwards from lower leaves. The entire leaf surface is covered by downy mildew coating, which is composed of sporangiophores and sporangia of the pathogen (Fig 9.1). The stem, branches and even capsules are attacked resulting in the premature death of the plants. The infection start from the moment the seed germinate and persist during the whole period of growth (Yossi fovitch 1929). Khristov (1943) reported that the pathogen often cause abnormal development in opium poppy. The pathogen also causes hypertrophy and curvature of stem and flower stalks.

10.1. Downy mildew of Plantago psyllium

Downy mildew is the major and serious disease of Plantago particularly P. ovata. It causes enormous quantitative and qualitative loss and often becomes a limiting factor in the successful cultivation of the crop (Desai and Desai, 1969). Usually the disease appears at the time of spike initiation.

Pathogen: Peronospora alta and P. plantaginis

Geographical distribution
Plantago ovata under commercial cultivation has been reported to suffer from downy mildew disease. Downy mildew occurs on ripe seeds of Spanish, French and European plantago. The downy mildew is a native of Mediterranean region especially Southern Europe, North Africa and West Pakistan.
The plantago commercially cultivated in Gujarat and to a limited extent in Haryana and Rajasthan provinces in India is observed to be infected with downy mildew.

Downy mildew has been reported on a wide range of ornamentals, especially those in home gardens, but only in a few instances the diseases have been sufficiently severe and widespread .Generally the diseases have been of most concern in a few ornamentals grown as crops either out doors or under glass or in nurseries, where many seedlings are raised in close proximity, often under humid conditions which favour this disease. Downy mildew having importance on ornamentals and flowering plants are:

11.1. Downy Mildews of Anemone (Windflower)

Two downy mildews are reported on cultivated anemones. The one is caused by Plasmopara pygmaea while the other is caused by Peronospora sp.
Pathogen .1. : Plasmopara pygmaea
It was first recorded in Britain on decaen anemones near Liskeard, Cornwall, in september 1917

Symptoms
It causes blackening of the foliage of the planting. The sporangiophores emerged from stomata at the periphery of the blackened zone. The fine white mildew covers the under surface of the leaves. Plants become discolored with aborted stamens. Oospores are found in the discolored tissues.

1.1 INTRODUCTION

Horticulture is defined as “The science and art of growing vegetables, fruits, flowers, ornamental plants and landscaping of gardens and surroundings in small and commercial gardens”. The word ‘horticulture’ has been derived from Latin language and consists of two parts, viz., ‘hortus’ means garden and ‘cultura’ means cultivation. Thus, the word ‘horticulture’ means garden cultivation. Horticulture basically deals with Pomology, Olericulture, and Floriculture and Landscaping. Horticulture is gaining importance as it gives more returns per unit area and also gives nutritious food to human beings thereby improves quality of life and enhances the aesthetic beauty of nature. Vegetable growing is one of the major branches of horticulture with respect to value of the products.

In technical sense all parts of vegetables are used for consumption. The term, however, is usually applied to the edible plants which store up reserve food in roots, tubers, bulbs, stems, petioles, leaves, buds, flowers, fruits, and seeds which are eaten either cooked or raw. Growing vegetables is not only important for providing the protective food but also serve as an important subsidiary food playing a more significant role in the food consumption. They are rich in nutrients and are essential components of a balanced diet.

2.1 INTRODUCTION

Vegetables are grown and consumed throughout the country either on small or commercial scale. Various terms have been used for vegetable gardening, based on the objectives for which they are grown and can be classified into various types depending on the acreage cultivated, method of cultivation and purpose of vegetable production. Based upon these facts, vegetable cultivation is divided into the following types of gardens:

Home or Kitchen Gardening: The purpose of this gardening is to supply the varieties of vegetables for family use.

Commercial Vegetable Gardening: This is the method of growing vegetables on large scale to earn profit and is further divided into seven types

3.1 INTRODUCTION

Tomato is one of the most versatile vegetable with wide usage not only in Indian culinary but also in world cuisines. Despite botanically being a fruit, it is generally eaten and prepared like a vegetable. Tomato is producing a very good source of income to small and marginal farmers and provides nutrition to the growing population. Sometimes, it is called poor man’s orange in India and Love of Apple in England. Tomato is one of the most important “protective foods” because of its special nutritive value. The100 g of edible portion of tomato contains 94.1 g of water,2.5 g of total sugar, 1.0 g of protein, 0.3 g of fat, 4.0 g of carbohydrates, 0.6 g of fibre, vitamin A (1100 I.U), vitamin B (0.20 mg), vitamin C (23 mg), malic acid (150 mg), citric acid (390 mg), oxalic acid (3.5 mg), potassium (268 mg), and phosphorus (27 mg). Tomato is a rich source of minerals, vitamins and organic acid. Tomatoes are the major dietary source of the antioxidant lycopene, which has been linked to many health benefits, including reduced risk of heart disease and cancer. It is used for treating chronic dyspepsia, bronchitis, asthma and also used as a blood purifier. Tomato fruits contain 20-50 mg of lycopene/100 g fruit. Tomatine is a steroidal glycoalkaloid present in tomato. Tomatine content is higher in leaves and f lowers than fruits. Tomatine content is 300 mg/100 g in small hard tomato fruits whereas in large green tomato it is 150mg/100 g. There are various types of f lavouring compounds found in fruits, which enrich the taste;so, several processed items like paste, puree, syrup, juice, ketchup, drinks etc are prepared on large scale. Tomato fruit aroma is due to sulfonium. Tomato acidity is due to citric acid and pH of the tomato juice is 4.5.Tomato is very good appetizer and its soup is said to be a good remedy for patients suffering from constipation. Three f lesh colours are found in tomato, namely, red (lycopene pigment), yellow (carotenoid) and tangerine (prolycopene).Tomato seed oil (24%) is used for manufacture of margarine. About 33% of total tomato growing area is covered by F₁hybrids which is highest among the vegetables grown in India. A book entitled Tomato was written by Dr. G. Kallo in 1986.

4.1 INTRODUCTION

It is an annual crop cultivated all over India, Bangladesh, Pakistan, China, Japan, South East Asia and Philippines. The fruits are available practically throughout the year. Brinjal fruits are a good source of calcium, phosphorus, iron and vitamins particularly ‘B’ group. A 100 g of edible fruit contains 91.5g of water, 6.4 g of carbohydrates, 1.3g of protein, 0.3g of fat and 0.5g of mineral matters. Its green leaves are the main source of vitamin C (38-104.7mg/100g). Dark purple brinjal has more vitamin C than those with white skin. Bitterness in brinjal is due to presence of glycoalkaloid solasodine. Generally, high amount of glycoalkaloids (20mg/100g) in the fruits produce a bitter taste and off flavour. Brinjal is reported to stimulate the intrapeptic metabolism of blood cholesterol and has marked drop in blood cholesterol level. The de-cholestrolising action is attributed due to the presence of poly-unsaturated fatty acids, PUFA (linoleic and linolenic) which are present in flesh and seeds of fruit in higher amount (65.1%). The presence of Mg and K salts also helps in de-cholestrolising action. Dry fruit is reported to contain goitrogenic principles. Aqueous extracts of fruit inhibit choline esterase activity of human plasma. Brinjal has got much potential as raw material in pickle making and dehydration industries. It is supposed to contain certain medicinal properties and white brinjal is said to be good for diabetic patients. The fruits are regarded as a cure for toothache. It is also an excellent remedy for those who are suffering from liver complaints. Cu content and polyphenol oxidase activity are highest in purple colour fruits and lowest in white fruit. Fe and catalase activity are highest in green fruited cultivars and lowest in white fruited cultivars. White fruited cultivars contain twice as much crude fibre as the purple and green fruited cultivars. Solanum ferox is yellow fruited type and is very popular in southern Europe, France and Italy and USA. Vitamin C content of brinjal is affected by canning. Toasting of fruits raises the nicotinic acid at the expense of trigonellin which is present in it and 66-69% of it is converted into nicotinic acid during toasting.

Brinjal is a self-pollinated crop but cross-pollination also occurs in it i.e., it is often cross-pollinated and pollination is mainly done by bumble bees and honey bees. To encourage pollination and visit of these bees, Mimosa pudica plants should be planted in the vicinity of brinjal. Brinjal flowers are divided into four types namely (i) long styled (ii)Medium styled (iii) pseudo-short styled and (iv) short styled. The maximum fruit setting in different cultivars is in long styled flowers which ranges from 70-86.7% and in medium styled it ranges from 12.5 to 55.6%. There is no fruit setting in pseudo-short and short-styled flowers. In India it is produced in an area of 0.669 million ha with a production of 12.4 million tonnes.

5.1 INTRODUCTION

Chilli is a tropical vegetable crop but considered as an important spice crop of India. Chilli is mainly used in culinary purpose for adding flavour, colour and pungency. It is consumed both in mature and immature stage. In immature form it is valued for pungency and in ripe dried form it is valued both for pungency and colour. Dry chilli powdered or ground into a paste and even green chillies are used for curries, sambars, rasam and other savory dishes to impart pungency, colour and flavour to food items. It is widely used in the manufacture of curry powder, curry paste and all kinds of pickles and preparing sauce, soups, salads etc. In food and beverage industries chilli is being used in the form of oleoresin which permits better distribution of colour, flavour in food. Capsaicin, the pungent principle, is present in cores or septa walls and placenta. It is used in the preparation of balms, whereas the colour extracts (Capsanthin/carotenoid pigments) find use as colour additives in food industry, poultry and prawn feed industry. Green chillies are rich in Rutin which has pharmaceutical use and known as Vitamin P. Oleoresin present in chilli permits better distribution of colour and flavour in food as compared to chilli powder due to cleanliness and uniform flavour. Oleoresin is used in preparation of processed products and also in a number of pharmaceutical formulations. A non-conventional use of chilli is for self-defence sprays of capsicum oleoresin at ultra-high emission rate which temporarily immobilizes the attacker. Highest pungent chilli of the world is Bhoot Jolokia/Naga King chilli (Capsicum chinensis) in NE India. Hotness of Naga king Chilli is 10,01,304 SHU (Scovonelle Heat Unit). At present chillies are grown in almost all states of the country. The major chilli growing states are Andhra Pradesh, Karnataka, Maharashtra, Odisha, Tamil Nadu, Madhya Pradesh, West Bengal and Rajasthan. Within a span of over four centuries, it has spread to an area of around 0.8 million ha. The area and production keeps varying depending on price fluctuations and the weather conditions. Area under chilli cultivation in India is 0.831 million ha with a production 1.87 million tonnes of dry chilli. Andhra Pradesh has been leading both in area and production contributing on average of 25 per cent of the total area and over 40 to 50 per cent of the total production. Chillies have adapted very well to the Indian condition so that, India is considered as secondary centre of origin.

6.1 INTRODUCTION

Capsicum is mostly consumed raw in green mature forms unlike in Europe and US where they are consumed in red ripe form in salads, cooked, mixed and stuffed vegetables. It is known as bell pepper because of its fruit shape. The fruits of capsicum are non-pungent, so popularly known as sweet pepper; but some cultivars are slightly pungent. Capsicums are grown throughout the Old world and New world as a commercial crop mainly in mid-hill regions or protected structures. Its cultivation is restricted to cooler regions of the world. In Spain, it is referred to as ‘pimientos’ due its red colour and sweet taste. Fruits are rich in vitamins C and D (beneficial to the vascular system), as well as vitamins A, B₁, and B₂. It has four different colours such as green, red, yellow and purple. The oleoresin extracted from bell pepper is of better quality than that extracted from Chilli.

7.1 INTRODUCTION

Okra is a remunerative vegetable crop for the tropical and subtropical regions of the world. Its fresh fruits are important vegetable in India, Brazil, West Africa and many other countries. For year-round consumption sun dried (Africa, India), and frozen and sterilized (USA) fruits are processed from fresh fruits. Tender green fruits are cooked in curry and also used in soups. The root and stem are useful for clearing cane juice in preparation of jaggery. Its ripe seeds are roasted, ground and used as a substitute for coffee in Turkey. Matured fruits and stems containing crude fibre are used in the paper industry. Okra is rich in vitamins, calcium, potassium and other minerals. A 100g consumable unripe okra fruits contain 10.4g dry matter, 3,100 calorie energy, 1.8g protein, 90mg calcium, 1.0mg iron, 0.1mg carotene, 0.07mg thiamin, 0.08mg riboflavin, 0.08mg niacin and 18 mg vitamin C. The dry seeds contain 13-22% edible oil and 20-24% protein. The seed cake is also used as an animal feed. Okra has high iodine content and it has ability to control goiter. Ratoon cropping can also be done in okra.

8.1 INTRODUCTION

Amaranth is one of the oldest food crops in the world, with evidence of its cultivation reaching well back to 6700 BC. The genus Amaranthus consists of nearly about 60 species, which includes leafy vegetables, vegetables for grains, ornamental plants as well as weeds. The word amaranth has actually been derived from the Greek word amarantos, which means unwithering and the people who used it symbolize immortality. The Hindi term for amaranth, Ramdana, means God’s own grain. Amaranthus tricolor L. is the most common species grown as leafy vegetable during summer and rainy season in India but it can be grown throughout the year. It fits well in crop rotations because of its very short duration and large yield of edible matter per unit area. The estimation of the extent of its cultivation is not available. Green or leafy types are usually grown in kitchen and market garden. Amaranth is more widely used as a potherb. The grain Amaranthus species are popular in the high lands of tropical and sub-tropical America. It is gaining importance in the Indian plains also, particularly in Gujarat and Maharashtra. Grain types are usually grown as mixed crops along with cereals, pulses and vegetables.

The leaves and tender stems of Amaranthus are rich in protein, minerals, vitamin A and vitamin C. A 100g of edible portion of Amaranthus consists of Protein 4.0 g, Calcium 397 mg, Iron 25.5 mg, Magnesium 247 mg, Phosphorus 83 mg, Potassium 341 mg, Sulphur 6 mg, Vit C 99 mg and Vit A 9200 IU. Besides, the soft fibrous matter provides necessary roughage in the diet

The fresh tender leaves and stem of Amaranthus are delicious when cooked and consumed like other leafy vegetables. The tiny seeds of grain Amaranthus are parched and milled for flour. Amaranthus flour compares favourably with other cereals in taste, nutritional value and yield. The grain Amaranthus is a rich source of protein and essential amino acids like lysine, leucine and isoleucine which are required for growth of children. In spite of several advantages of amaranth as leafy vegetable, both its stems and leaves also contain the anti-nutritional factors such as nitrate and oxalate, which can be removed by cooking with ample water. In general, the presence of oxalates causes the kidney stone, while that of nitrates causes methaemoglobin in blood. Therefore, it is recommended not to consume leaves of more than 200 g/day/head.

9.1 INTRODUCTION

Cluster bean is grown in India to a lesser extent than other beans. It is a commercial crop of arid and semi-arid regions. It is grown for its green pods that are used as vegetable and dry seeds. It is also grown as forage and green manure crop. Among leguminous crops it is comparatively hardier, drought resistant and cultivated on a large scale as a forage crop in dry regions because of its deep tap root system which enables it to recover from water stress. Some of the cultivars are used for extraction of gum called as guargum. The gum obtained from this crop is like a mucilaginous substance called galactomannan that is used in various industries particularly textiles, cosmetics, explosives and paper. Due to its colloidal nature, the gum acts as a stabilizer and thickener in food products,viz., ice cream, bakery mixes and salad dressings. The seeds of clusterbean contain about 30-33% gum in the endosperm. The gum in the seeds are galactomannan polysaccharides. The discovery of the galactomannan gum in the endosperm during 1948, led to its importance as an industrial crop. Today it is one of the significant foreign exchange earners of the country. Fresh pods contain 82.5% water, 9.9% carbohydrate, 3.7% protein, 0.2% fat, 2.3% fibre and 1.4% mineral matter. Cyamopsis senegalensis is the ancestor of guar. The largest growing state is Rajasthan (82%). Young plants of cluster bean contain hydrocyanic acid which causes toxicity to animals. It is an amide (asparagine and glutamine) producing legumes.

10.1 INTRODUCTION

Cowpea is a typical warm season crop adapted to tropics. It is grown both for its tender pod and dry seed that is used as pulse for culinary purposes. The pods are rich in protein, vitamin B and minerals. It is also used as a fodder and green manure crop. On dry weight basis the cowpea seeds contain 23.4 % protein, 1.8 % fat and 60.3 % carbohydrates. Most probable progenitor of cowpea is Vigna unguiculata var mensensis. It is grown as a catch crop that is drought tolerant and sensitive to water logging. Being a legume crop, cow pea fits well in different inter-cropping systems. It is mainly of two types. Asparagus bean/yard long bean/snake bean (Vigna sesquipedalis) has 30-90 cm long fleshy pod with elongated kidney shaped 8-12 mm long seeds. It is late maturing variety. While catjang bean (Vigna catjang) has 7-13 cm long pods with 5-6 mm kidney shaped seeds. Pulse type of cowpea is Vigna uniguiculata var radiate and dual-purpose cowpea is Vigna uniguiculata var cylindrica.

11.1 INTRODUCTION

The term ‘Dolichos’ derived from Greek language means long pod and ‘lablab’, an Arabic term, means production of sound by dried seeds in the pods. In India, it is grown all over the country but compact large acreage for commercial production is uncommon. It is grown for whole pod. Fresh seeds and dry seeds are used as pulse grain. It is used as pod vegetable, feed and green manure crop. It is very popular in villages as well as cities where less area is available for cultivation. The young tender leaves are used in salads and the relatively old leaves are cooked as potherb like spinach. Its fresh green pods contain 86% moisture, 3.8% protein, 6.7% carbohydrate, 0.7% fat, 0.9% mineral matter, Vitamin A 312 IU. It is good source of Vitamin B, Vitamin C, proteins, minerals and dietary fibres. Trypsin inhibitor and several anti-nutritional factors such as tannins and phytates are present in mature and dark coloured seeds. On heating it is broken down into toxic cyanogenic glucoside which is soluble in boiling water. Therefore, it is necessary to boil the mature seeds in water before consumption. Sem is of two types.(A) Dolichos purpureus var. typicus (Graden Type) is with soft, edible pod wall having less fibre. (B) Dolichos purpureus var. lignosus(Field bean) that is grown for fresh dry seed as pulse, pod wall has high fibre content and has characteristic aroma. Hyacinth bean is a perennial herbaceous plant often grown as an annual and pole types are photosensitive.

12.1 INTRODUCTION

French bean (Phaseolus vulgaris L.) is one of the most important legume vegetables grown for its tender green pods for fresh consumption, processing and dry seeds. The pods are slender, 10-25 cm long, straight or slightly curved with prominent beak. Seeds are kidney shaped, elongated and white, red, purple or blackish in colour or mottled. The vegetable is in great demand in cities and is grown both commercially and in home gardens. Its major area is confined to hills, where it is grown for green pods. Punjab, Jammu and Kashmir, Gujarat, Karnataka, Tamil Nadu, Uttar Pradesh and Himachal Pradesh are the main states where it is being cultivated on large scale. Dry bean seeds are an excellent source of cheap protein and many cultivars contain 22-23 % protein. Hundred grams of edible fresh pods contain 91.4 % water, 1.7 % protein, 0.1 % fat, 0.5 % mineral matters, 4.5 % carbohydrates, 50 mg Ca, 28 mg P and 1.7 mg Fe. Its 100 g dry seeds contain 9.6 % water, 24.9 % protein, 0.8 % fat, 3.2 % mineral matters, 60.1 % carbohydrates, 60 mg Ca, 433 mg P and 2.4 mg Fe. In India, it is mostly grown for fresh consumption, while in USA it is grown for processing in large quantities. Dried beans are rich in protein and closely compared with meat. Phaseolus oborigineus is the progenitor of French bean. They are capable of utilizing atmospheric nitrogen with the aid of bacteria found in the nodules on the roots of the plants. Four cultivated species are seen under the genus Phaseolus, i.e., Phaseolus vulgaris—common red kidney bean, Phaseolus coccineus—scarlet runner bean, Phaseolus lanatus— Lima bean, Phaseolus acutifolius var. latifolius—Moth bean or Tapery bean. All the species are self-pollinated except lima bean which is often cross-pollinated and Phaseolus coccineus is generally cross-pollinated and long day plant.

13.0 INTRODUCTION

Cucurbits belong to the family Cucurbitaceae, commonly known as the melon or gourd family. The term cucurbits was coined by Dr Bailey. From nutritional point of view, cucurbit seeds are valued for their high oil and protein contents. Seed proteins and methionine of cucurbits are higher than legumes. Vegetatively propagated cucurbits are pointed gourd, ivy gourd and chow-chow. Long day of 16 hours and high temperature result in maleness. Short day of 9 hours results in femaleness. They are widely distributed in the tropics and warm temperate regions of south, southeast and East Asia, Africa including Madagascar, and central and south America. Cucurbitaceae family is represented by about 117 genera and 825 species. The most common uses of cucurbits are as vegetables and fruits. They are valuable sources of vitamins and minerals. The important cucurbits that are cultivated commercially are cucumber, watermelon, musk melon, long melon, round melon, bottle gourd, bitter gourd, ash gourd, ridge gourd, sponge gourd, pumpkin, squash, snake gourd, pointed gourd, spine gourd, ivy gourd and chow-chow etc. Cucurbits are used as vegetable, salads, dessert and pickle, and for making of sweets.

Vegetable: Bitter gourd, ridge gourd and sponge gourd, round gourd, pointed gourd and pumpkin are used as vegetables. Immature fruits of musk melon are also cooked as vegetable only in some areas.

Salad: Excellent salad is made from cucumber and little gourd.

Dessert: Muskmelon, water melon and cucumber are used as desserts.

Pickle: Cucumber, little gourd and bitter gourd are used for making pickles.

Sweets: Pointed gourd and ash gourd are used for making sweets.

14.1 INTRODUCTION

Drumstick is one of the most popular perennial tree vegetables in the south Indian households and known as miracle tree. This perennial vegetable survives for several years and goes on yielding vegetables without much care and attention, and is planted on the side of the kitchen garden without much interference with tillage operations of other annual crops. The fruits, leaves and flowers are used in culinary preparation. Immature fruits are cut into pieces and used in several culinary dishes. Fruits are rich in Vitamin C, carotene, Phosphorus and minerals like Mg, K, S, Cl etc. Tender leaves and flowers are comparable to that of Colocasia in vitamins and minerals. Drumstick leaves contain high amount of vitamin A (four times more than carrot), vitamin C (seven times more than orange), protein (5-10%), calcium (four times more than milk) and potassium (three times more than banana).The roots of the plant are used for seasoning pickles. Its roots are a good substitute for Horse Radish so called as Horse radish tree. It is highly valued for the distinct and appealing flavour for its tender fruits. They are rich source of protein, minerals and vitamins. Seeds contain an oil called ben or behen oil which has been much used for illumination, soap industry and highly priced for lubricating watches, computers, delicate machinery and so known as Ben oil tree. Seeds contain 38-40% of non-drying oil which is clear and odourless, that never becoming rancid. The oil contains high levels of unsaturated fatty acids, especially oleic acid up to 67.8%. It is edible and useful in the manufacture of perfumes and hair dressing. The press cake remaining after oil extraction is high in saponin, not edible, but utilized as manure. The oil cake is a water coagulant and used for purifying effluent water. It is used as organic substitute for water purifying chemicals such as aluminium sulphate. Wood yields blue dye and coarse fibre. The plant is used for treatment of rheumatism and as cardiac and circulating system stimulants. It has fragile and cory stem. The trunk is gaining importance as a raw material for paper making. The gum of stem has medicinal properties. The leaves are usually tri-pinnate with elliptic leaflets. Seeds are trigonous with wings on angles. Flowers are produced on current seasons growth on large and erect panicles or monocladial cymes. Flowers are yellowish creamy white and sweet smelling. It is a cross-pollinated crop. Pollinator is carpenter bees, bumble bee, honey bee and flee beetle. Flowering mostly varies from place to place and is greatly influenced by rain, temperature, humidity, wind, soil moisture and soil temperature etc. Peak period of flowering in central parts of India and Kerala is December-January while in southern part it is February-March and July-August with maximum flowering in February-March. Fruits take 60 days for horticultural maturity during rainy season while 30 days in summer.

15.1 INTRODUCTION

Curry leaf is an important perennial tree vegetable cum spice crop of India mostly used in South Indian culinary preparations for flavouring food stuff. It is an underexploited crop. The leaves have slightly pungent, bitter and feebly acidic taste and they retain their flavour and other qualities even after drying. Curry leaf is used in many of the Indian Ayurvedic and Unani prescriptions. It has many industrial values and medicinal uses. Its leaves, roots and bark are credited with tonic, stomachic and carminative properties. Leaves are reported to cure piles and allay heat of body. The green leaves are said to be eaten raw for treatment of dysentery. External application of pulped bark and root is reported to relive eruptions and bites of poisonous animals. An injection of toasted leaves is used to stop vomiting. The tribal people of India use its ground bark to rub on the bitten Part As a snake bite remedy. The powdered leaves are also used to aid in healing of fresh cuts. The dried curry leaf powder is also a good spice powder for use in the food stuff preparation and is exported. Fresh leaves on a steam distillation under high pressure yield 2.6 % (curry leaf oil) volatile oil which is used as fixative for heavy type of soap and perfume. Rectified leaf oil is deep yellow in colour with a strong spicy odour and pungent clove like taste. A volatile oil, a crystalline glucoside ‘Koenigin’ from the leaves and ‘Murayam’ from the flowers are industrial products. Curry leaf is grown on large scale in West Bengal, Assam, Deccan plateau, Western Ghats, Tamil Nadu, Karnataka and Kerala. It is cultivated in Coimbatore, Salem and Tiruchirappalli districts of Tamil Nadu on a commercial scale.

16.1 INTRODUCTION

Portulaca is an annual potherb, but may be perennial in the tropics. In many parts of the world, it is still regarded as a weed with nutritional potential. Its young stems and leaves are succulent and edible with a slightly acidic and salty taste. Stems are glabrous, f leshy, purplish-red to green, arising from a taproot, often prostrate, forming mats. It is described as a power food of the future because of its high nutritive and antioxidant properties. It contains more omega-3 fatty acids (300 to 400 mg/100 g of fresh leaves) than any other leafy vegetable plant. Succulent leaves and stem also contain dietary minerals, such as calcium, phosphorus, iron and potassium, as well as vitamins A, C and E and some amount of vitamin B and carotenoids. It has been recommended as a cholesterol lowering agent and as a therapy for arteriosclerosis. Generally, roots and leaves contain more iron and manganese than stems. Due to oxalic acid and nitrate content, excessive consumption of purslane is not recommended. The cultivated form of Purslane, i.e., Portulaca oleracea (garden or green purslane) and Portulaca sativa (yellow leaves, less hardy than the green purslane but possessing the same qualities), is hexaploid. Purslane is a succulent and well-branched herb, leaves are spirally arranged, f lowers are yellow, stamens 7-10, style with arms, fruit ovoid, capsule, seeds numerous, tiny and black in colour.

17.1 INTRODUCTION

Basella is a short-lived but productive leafy vegetable of the tropics. Its resistance to pests and diseases makes it very promising for small-scale production in home and market gardens. The plant is a climbing vine with thick fleshy stem and leaves. They are chopped and cooked as vegetables and has ornamental value too. Its leaves are rich source of vitamin A (3250 IU/100g), protein (1.2%) and rich source of iron (1.4mg/100g). The succulent leaves with petioles and tender leaves are cooked as vegetables. The plant is a climbing vine with thick fleshy stem and leaves. It was cultivated since long in South-East Asia and China, and is now widespread throughout tropical Asia, Africa and America. It is a popular vegetable in Malaysia and the Philippines. The colouring matter present in the red cultivar is reported to have been used in China as a red dye for official seals, as ink. These are used to allay fever and as a mild laxative for pregnant women. A decoction from the plant is used to alleviate labour pains. Boiled leaves are used as a poultice. Flower spikes are sold as vegetable in northern Thailand markets. Flowers have been reported as an antidote to poisons. Fruit juice is used as eye-drops in the treatment of conjunctivitis. Cooked roots are used to cure diarrhoea, while cooked leaves and stems are used as a laxative. The red types of Ceylon spinach are very popular ornamentals and are grown as a pot plant in Europe.

18.1 INTRODUCTION

Sorrel is a perennial herb, which is found in grassland habitats throughout Europe from the northern Mediterranean coast to the north of Scandinavia and in parts of Central Asia. It is of two types such as Garden sorrel that is a native of Europe and south western Asia and French sorrel that is originated in the mountains of southern France and the southern and central regions of Europe and south-west Asia. The name sorrel is derived from the Germanic word, Sur and the old French word Surele, both meaning sour. It is primarily used as a culinary herb for its leaves, which are used in salads too. The leaf of this plant resembles that of spinach and have a lemony lettuce flavour and the plant is well known for strong acidity in Europe and the United States. Sorrel is a rich source of potassium, iron and vitamins A, B₁ and C. The flavour of sorrel leaves is mainly due to oxalic acid, which is harmless when consumed in small amount. Owing to high level of vitamin C content, it was rightly believed to protect against scurvy disease. It is a dioecious plant, that bears unisexual flowers, as the male and female flowers appear on different plants. When the plant flowers, they look very attractive and are often used as an ornamental plant.

18.2 CHOICE OF CULTIVARS

In India, it is not a common leafy vegetable and is grown on a limited scale, mostly in kitchen gardens. Even in Europe and other countries, different local strains are grown for both home gardening and commercial cultivation. Profusion is a cultivar, which mutated naturally in France and produces only leaves without forming seed, and hence, the plant always has fresh and ready to pick leaves.

19.1 INTRODUCTION

Roselle is a perennial shrub but grown as an annual. In the seventeenth century, the vegetable types were introduced to India and the United States of America. It is locally known as Mesta or Meshta in the Indian subcontinent. It is one of the important fibre crops, which stands next to jute in production. In India, mesta is grown in larger parts covering areas from Karnataka to Tripura including Maharashtra, Andhra Pradesh, West Bengal, Bihar, Odisha and Meghalaya. However, Andhra Pradesh has maximum area under mesta in the country. In many tropical regions, it is a popular vegetable, which is cultivated for its leaves, stems, seeds and calyces. Tender young leaves are eaten as a vegetable and the red calyces surrounding the fruit can be used to prepare non-alcoholic beverages and as colouring reagent for jelly, jam, and beverages. The stem is utilised for extraction of fibre. The plant stalks are used in making paper pulp, structural boards, as a blend for wood pulp and thatching huts. The leaves are a source of mucilage used in pharmaceuticals and cosmetics. Culinary cultivars are many branched, bushy and generally 1-2 m tall.

19.2 CHOICE OF CULTIVARS

Roselle is cultivated as a vegetable as well as fibre crop. In the beginning the tender leaves, stems and calyces are consumed. In the later stage it is used for fibre. The details of cultivars developed by different institutes and State Agricultural Universities for various uses are given below