eChapters

To fully explore the history of medical and drug development, it would be necessary to go back as early as 13,000 BCE, where drawings on the Lascaux caves in France suggest that humans were using plants for medicinal purposes. Since then, medical traditions have evolved and dissolved across societies all over the globe. Natural products including plants, animals and minerals have been the basis of treatment of human diseases. The last two centuries have seen a focus on scientific medicine, with a focus on drugs whose effects that have been proved by the scientific method. Yet given this setting, many of the major pharmaceutical corporations have renewed their strategies in favor of natural product drug discovery. Numerous drugs have entered the international pharmacopoeia via the study of ethnopharmacology and traditional medicine. At this point in history, it is possible for both traditional and western medicine to benefit from collaboration between the two disciplines. For traditional medicines, newer guidelines of standardization, manufacture and quality control and scientifically rigorous research on the scientific basis for traditional treatments will be required. In return, traditional medical traditions can offer a more holistic approach to drug design and myriad possible targets for scientific analysis. Powerful new technologies such as automated separation techniques, high-throughput screening and combinatorial chemistry are revolutionizing drug discovery. Traditional knowledge can serve as powerful search engine, which will greatly facilitate intentional, focused and safe natural product drug discovery and help to rediscover the drug discovery process. By looking at the historical trends in drug and medical developments, it is possible to understand how current drug development will benefit from this partnership.

‘Fungi’ including ‘mushrooms’ are ‘Thallophytes’, which do not possess chlorophyll and have been classified under the Kingdom - Myceteae. They do not have stems, roots and leaves and they lack a vascular conducting system as in the case of plants. They propagate by means of spores, either asexual or sexual. Though almost all the fungi are microscopic, the mushrooms are among the largest fungi and had attracted the attention Scientists and Naturalists of many countries dating back to centuries. The Greek word ‘mykes’, which means ‘cap’, was given to the mushrooms because of the ‘cap-like’ appearance of the pileus and the Greek word ‘Mycology’ (mykes = mushroom + logos = discourse) denotes the study of mushrooms. What we call mushrooms, are actually the sporocarps produced by several species of fungi, while the mycelium that produces them live in various types of substrata and obtain nourishment from them. Usually, the fleshy, macroscopic fruiting bodies or sporocarps produced by fungi belonging to Basidiomycetes and Ascomycetes are called ‘mushrooms’

The Romans attributed the appearance of mushrooms and truffles to lightning hurled by Jupiter to the earth. Even now in India and several other countries, people believe that mushrooms appear only after lightning and thunder. The Greeks believed mushrooms as ‘Food for the Gods’. The Romans supplemented mushrooms in the food of soldiers for strength and vitality. The much-priced mushrooms were supposed to be the food delicacy of the elite society of the Romans and Greeks in olden days. The Chinese consider mushrooms as a cure for many diseases and they believe that mushrooms increase the longevity. A number of medicines in all forms are prepared from mushrooms by the Chinese.

FRUIT CROPS

Banana (Musa species)

1. Panama disease of banana
Fusarium oxysporum f.sp. cubense

‘Panama disease’, ‘Fusarium wilt’ or ’vascular wilt’ of banana is one of the most serious and destructive diseases of the crop. The disease was first reported from Australia in 1874. Now, it is widely distributed all over the world, including America, Africa, Sri Lanka, Burma, Thailand, Malaysia, Indonesia, Hawai, Fiji, the Philippines, India, Australia and New Zealand. In India, it is prevalent in the states of Assam, Bihar, Karnataka, Kerala, Tamil Nadu, Telungu Desam, Maharashtra and West Bengal.

Symptoms. Usually the symptoms are manifested, when the banana plants are about 5 months old. However, under highly favorable conditions for the pathogen, even 2 - 3 months old plants show wilt symptoms. Initial visible symptoms appear as pale yellow streaks, lengthwise in the petioles of the oldest, lowermost leaves. Two types of symptoms follow this. In the first type, the old leaves turn yellow progressively and finally they break from the petiole and hang down. In the second type, the leaves break from the petiole and hang down, without becoming chlorotic. Gradually, all the leaves collapse and hang down, except the crown, which alone stands upright. The newly formed leaves show yellow blotches and wrinkling of the lamina. Often, the leaf sheaths covering the pseudostem show longitudinal splitting above the ground level. But, sometimes this symptom may not appear. The affected plants may die completely in about 4-6 weeks after the appearance of yellow streaks on the petioles.

The vascular strands show discoloration varying from yellow to dark- brown, which is the characteristic internal symptom of the disease. The discoloration usually appears first in the outer leaf sheaths and extends to the vascular strands of the pseudostem. Vascular discoloration is more pronounced in the corms, but is not common in the roots. When the rhizome of an infected plant is cut transversely, the discoloration of the vascular bundles is distinctly seen as numerous, pin-point like dots all over the cut surface. The roots of affected plants become black and rotten. The suckers growing from the diseased corms are systemically affected and they wilt and die very soon (Fig. 71).

The causal organism. The mycelium of the fungus is hyaline, septate, much branched and mostly intracellular. Few hyphae may also be present in the intercellular spaces. The hyphae are largely confined to the vascular bundles, often filling the cavity of the vessels. The fungus produces three types of spores viz., macroconidia, microconidia and chlamydospores. The sporodochia bearing conidiophores and conidia emerge through the stomata on the petioles and leaves. The conidiophores are vertically branched. Macroconidia are borne at the apical ends of the main and lateral branches and are formed in succession one after another. They are thin-walled, hyaline, pedicellate, sickle-shaped, with both ends somewhat pointed, 2 - 5 septate, mostly 3-septate and measure 22.0 - 36.0 x 4.0 - 5.0µ in size. Microconidia are produced from the branches of conidiophores or from the tips of hyphae in very large numbers. They are single-celled or two-celled, thin-walled, hyaline, ovate or elongated and measure 5.0 - 7.0 x 2.5 - 3.0µ in size. Terminal or intercalary chlamydospores are formed from the hyphae, as well as from the conidial cells. They are oval or spherical, thick-walled and usually occur in pairs. They measure 7.0 - 13.0 x 7.0 - 8.0µ in size (Fig. 71).

The fungus is a facultative parasite. It can invade the host mainly through wounds in the corms or roots. After entry, the fungus develops extensively in the vascular tissue of the corm and then proceeds systemically to the leaf sheaths and pseudostem through the vascular system. The fungus colonizes the vascular bundles and produces masses of mycelium, which bear conidia and chlamydospores, filling the cavity of the vessels. The plugging of vascular elements by the fungus obstructs the translocation of water and nutrients to the aboveground parts of the plant leading to wilting and death of affected plants.

Mode of survival, spread and epidemiology. The fungus is soil-borne in nature. It can survive saprophytically in the diseased corms and other plant parts for prolonged periods and cause fresh infection. The chlamydospores can also remain in a viable state in the soil and diseased plant parts for a long time. The disease can be easily spread through spores present in the infected banana trash and soil, which may be carried in surface flooded water. Suckers used for planting from diseased areas to other places spread the disease easily. Contact of the roots of healthy plants with the roots of diseased plants carrying the spores also leads to fresh infection. The entry of the pathogen is mostly through wounds in the roots or corms, especially deep wounds up to the xylem vessels, caused incidentally during cultural operations or by soil-inhabiting pests, particularly nematodes.

Light textured, sandy loam soils, with acid reaction and low soil moisture of 25 % favor the occurrence and development of the disease. Ratooning of infected banana plants increases the disease incidence to a great extent and leads to continuous accumulation of soil inoculum.

CEREALS

Rice (Oryza sativa)

1. Rice blast
Pyricularia oryzae

‘Rice blast’ occurs in more than 80 countries across the world. The disease is more prevalent in Thailand, Japan, America, Guyana, Philippines and India. It is particularly serious in places, where rice is irrigated or receives heavy rainfall and where high levels of nitrogenous fertilizers are applied. Rice blast was first reported in China in 1637, in Japan in 1704 and in India in 1913. In India, it is found in all rice growing states, particularly in Telungu Desam, Karnataka, Maharashtra, Uttar Pradesh. Assam, Tripura, West Bengal, Bihar, Orissa, Himachal Pradesh, Punjab, Madhya Pradesh, Gujarat, Kerala, Tamil Nadu and Pondicherry and causes considerable damage to rice crop. In Tamil Nadu, the disease occurs in all rice growing districts and attains epidemic proportions in some seasons. Several rice blast epidemics have occurred in different parts of the world, causing yield losses ranging from 50 to 90 %. In Tamil Nadu, a serious epidemic of the disease occurred in 1919 in the Thanjavur Delta.

Symptoms. The disease, though chiefly a foliage disease, attacks other parts of rice plants, such as leaf sheath, rachis, joints of the culms and even the glumes. On the leaves, the initial symptoms appear as small bluish or grayish specks, which remain circular in older leaves. On young leaves, they enlarge and become eye-shaped, diamond-shaped or spindle-shaped spots, extending over several centimeters in length and about 1.0 cm. in width. The central portion of the lesion appears pale green or grayish green and water-soaked in the beginning. In older spots, the center becomes white to gray with a dark-brown margin surrounded by a yellow hallow. The lesions may coalesce, cover large area of the leaves and eventually the entire leaves are killed. The shape, size and color of the spots vary depending upon the variety, growth stage of the plants and environmental conditions. Similar spots may be formed on the leaf sheath also. During severe incidence, large areas of the leaves dry and die and the entire crop presents a burnt appearance. Hence the disease is known as ‘blast disease’. Leaf blast is more severe during the seedling and maximum tillering stages. In the nursery, the seedlings show numerous spots on the leaves, which wither and die. In case of severe infection, large number of seedlings may die. Blast also affects the leaf collar, which results in the death of the entire leaf.

The disease attacks the stem-nodes at the heading stage leading to production of ‘white panicles’ or the stem may break at the infected node. Rarely the internodes are affected. Further, at heading the fungus also attacks the panicle neck, which is girdled and becomes shining black and shrivelled. This is the most destructive phase of the disease and is known as ‘neck blast’, ‘neck rot’ or ‘panicle blast’. If infection of the panicle neck occurs early, the grains become chaffy and the panicle remains erect. If panicle neck infection occurs late, the grains become partially filled and because of the weight of the grains, the panicle breaks at the neck- node and droops. Sometimes, only parts of the panicle and joints of the culms and some glumes are infected and develop brown to black spots (Fig. 1).

Under conditions highly favorable for the pathogen, even the varieties resistant to the fungus under normal conditions are also attacked and small, round or short elliptical spots develop. However, the spots normally do not enlarge as typical blast spots.

7.1 Economics and Valuation of ghgs emissions

Since the late 20^th century, it has been largely accepted that cause of high concentration of GHGs in atmosphere is induced by human activities. Greenhouse gas emissions and related climate change has opened up debate on overall economic losses and ways to reduce these loses. Moreover, apart from curbing monetary losses; the global political leaders as well as reputed economists are looking towards making money by saving the emissions. Recently, the researchers have started to emphasize on the actual value added to the ecosystem by curbing emissions, discrete of the economic benefits. This section will discuss the economics and ecosystem services related to the management of GHG emissions.

Origin

The initiative to curb the emissions started in 1992 with the United Nations Framework Convention on Climate Change (UNFCCC) at the Earth Summit in Rio de Janeiro. The Convention took place from 3 to 14 June, 1992. The UNFCCC is an international environmental treaty designed to “stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system”. The UNFCCC had non-binding limits on greenhouse gas emissions for individual countries and the framework was only meant for formulating precise international treaties (called “Protocols” or “Agreements”). It contained no execution mechanisms, however, it considered some negotiations and suggestions to formulate the action plans and regulation guidelines under UNFCCC to fulfill the objective of reduction of GHG emissions to the desired level.

What is mitigation of GHGs emission? We must be clear about the answer of this fundamental question. In simple term, the mitigation of GHGs emission is the way or means by which the emission of those gases could be reduced. As we know from the previous chapters of this book that the GHGs emission could be occurred from natural as well as anthropogenic activities. Natural activities included volcanic eruptions, ocean current fluctuations, continental drifts which are responsible for emission of huge amount of CO₂ and other GHGs. The reduction of emissions from those natural activities is beyond our capabilities. However, the human induced emissions of GHGs emission could be reduced. We studied in previous chapters that fossil fuel burning, industrial and energy sector pollution, deforestation, land use change and agricultural could contribute to GHGs emission considerably. Mitigation techniques are different for each of those sectors that governed by lot of interrelated factors. In actual sense, the mitigation of GHGs emission should includes all the measures that can curtail the anthropogenic emission from all sectors. But that is out of the scope of this book. In this book, we specifically address the mitigation principles, options and efficiency of different techniques/ practices in agriculture only.

In that aspect, the mitigation of greenhouse gases emissions in agriculture is defined as “the means and ways by which emissions of GHGs could be reduced from agriculture”. The ways and means actually referred to the techniques and practices and their amalgamation in agricultural sector both in production, processing and consumption aspects. So, mitigation is not only a techniques or combination of techniques it is actually an integrated approach for reducing greenhouse gases emission from agricultural systems. Primarily, there are two complementary approaches for mitigation of GHGs emissions from agriculture. Those two approaches are (i) supply-side and (ii) demand- side options or pathways. The supply-side approaches includes scientific land- use-changes, improvement of crop management, better livestock management practices, enhancing carbon storage in biota, soil carbon sequestration, significant substitution of fossil fuel by bio-fuels and use of renewable energy in agriculture. On the other hand, demand side approaches, taken in to account of shifting in the dietary pattern from non-vegetarian to vegetarian, curtail down the food loss and waste, and reducing the supply-chains (Figure 6.1). We can see, most of the approaches in supply-side are technology driven, while, approaches in demand-side are socio-economical and or policy driven. In this chapter we would thoroughly discuss the principles of mitigation, options of mitigation, mitigation cum adaptation approaches to reduce GHGs emission and climate change and few strategies to cope up with the vagaries of climate change.

5.1 Impact of climate change on agriculture

Climate change has both positive and negatively impact on agriculture, food security and land degradation. Climate change could exacerbate the land degradation processes by increases in rainfall intensity, drought frequency and severity, dry spells, f looding, heat stress, sea-level rise and permafrost thaw. The 1/4^th of ice-free land area in the world is prone to human-induced anthropogenic degradation (Certini and Scalenghe, 2011; Hooke et al., 2012). Soil erosion rate is 20-100 times faster than that of soil formation in agricultural field. The erosion rate is least is zero-tillage (non-disturbed field) and maximum at conventional intensive tillage practices. Climate change further exacerbates the land degradation. The permafrost areas, dry-lands, low-lying coastal regions, river deltas are more vulnerable. The occurrence of drought in dry-land was increased by around 1% per year during 1961-2013 periods. On an average 380-620 million people globally experienced desertification who lived in dry-land areas (1980s and 2000s) in South and East Asia, North Africa, Middle East, Sahara region, and Arabian peninsula. Moreover, people who are already living in degraded/ desertified regions are more negatively affected by climate change.

Specifically, the land surface air temperature has increased about twice as much as the global average temperature since the pre-industrial era. The land-surface air temperature has increased relatively higher than the world’s average surface (land and ocean) temperature since the pre-industrial era (1850-1900). The average land-surface air temperature has enhanced by 1.53°C (1.38-1.68°C), whereas, world’s surface (including land and ocean) air temperature has enhanced by 0.87°C (0.75-0.99°C). Subsequently, global warming triggered the frequency, intensity and duration of heat waves and related damage. The direct and indirect impacts of climate change on global agriculture is summarised below for an overall idea about the importance of the issues.

The measurement of greenhouse gases (GHGs) has been started during middle of the last century. Initially, CO₂ and water vapour were measured with other common meteorological variables like temperature, sunshine hours, rainfall, humidity etc., for monitoring the weather condition and pollution. The absolute or relative concentrations of gasses in atmosphere are used to measure basically for monitoring purpose. However, limited studies were dealt with actual gaseous exchanges of fluxes. The concern about gaseous flux measurement and GHGs-exchanges started after 1900s when people got concerned about anthropogenic pollution, environmental sustainability and climate change issues. The GHGs-exchanges in earth-atmosphere systems primarily occur due to change in meteorological variables, soil responses and physiological activities of crops. If we are interested for environmental data inventories, then absolute GHGs concentrations of atmosphere at a specific time is required. However, presently researchers, students, environmentalists, climate scientists are primarily interested for quantitative data on GHGs fluxes and or GHGs-exchanges. They want to know what and how much quantity of a particular GHG is emitting from unit area at unit time.

Flux refers to the amount of any gas emitted per unit area per unit time. The dimension of that is M A^-11 T^-1. (Where, M= Mass/ Quantity; A= Area; T= Time). The SI unit of flux is g m²s^-1. Therefore, flux is a vector. It has magnitude as well as direction. As for example positive flux of CO₂ from earth surface means, CO₂ is moving out from earth surface to atmosphere. If it moves in opposite direction then the flux would be negative. In that case CO₂ gas may be absorbed by the soil surface from adjacent atmosphere. Similarly, GHGs fluxes of earth surface are either positive or negative. Generally, positive GHGs flux refers to emission of GHGs from earth to atmosphere and vice versa.

3.1 Chemistry of greenhouse gases (ghgs)

Greenhouse gases (GHGs) are atmospheric-gases that have capabilities to absorb and radiate-back the infrared (IR) radiation in the earth-atmosphere system (Figure 3.1). In this process the atmospheric-gases absorb and radiate- back IR radiation in lower atmosphere effectively emitting and absorbing heat energy heat energy. They maintain the heat budget of earth-atmosphere and keep our plant warm. If we typically see the chemistry of those gases, the key point is that they should have dipole moments. This is the property which makes them capable to absorb and radiate-back the range of IR radiation. In a molecule when valence-electrons are not equally shared in a bond between the two atoms, a slight positive charge is developed above one atom and a negative charge on the other atom. That charge difference of the different atoms in a molecule generates the dipole moment. For instance, in water vapour (H₂O- vapour), an unequal sharing of electrons and or separation of charge causes dipole moment. In H₂O, the centre has a positive charge at the hydrogen atoms and negative charges are located on the oxygen atom. The magnitude of dipole- charges, vibration and stretching of O-H bond generates certain frequency of the oscillating dipole moment that actually regulates the absorption capacity of IR radiation by H₂O vapour.

Climate change is caused by both natural as well as anthropogenic causes and it has been changing since the inception of earth-atmosphere (Figure 2.1). In a broader sense, anthropogenic activities (human activities) also must be considered as natural one in longer time scale as human and their activities are also a part of natural-ecosystem-functions. Among the natural phenomena, volcanic eruptions and continental drifts significantly affect the earth’s precipitation and temperature. A huge volume of CO₂ is released due to volcanic eruption at a little span of time-period which heated up the earth-atmosphere. Climate variability is primarily governed by rise in sea temperature, movement of warm water from the Western Pacific towards Peru, and El Nino which occurs at an intervals of 3-7 years. Climate variability also influenced the alteration in temperature and precipitation world wide. And persistent climate variability cause long term climate change. Therefore, basically three drivers that causes climate change are, the alteration in the energy of sun received by earth-atmosphere (natural causes), variations of ref lectivity of earth-surface- atmosphere system (natural as well as anthropogenic causes) and fluctuations in the greenhouse effect (natural as well as anthropogenic causes).

1.1 Weather

Firstly, what is weather? Simply, the conditions in the atmosphere above the earth is called weather. It refers to the conditions such as wind, rain and temperature, prevailing at a particular location during periods of hours or days. We often ask “what’s the weather like today”? Any individual can answer to this question as it requires only a short term experience or say exposure to the atmosphere. The TV news forecasters predict weather each day and inform about the temperature, cloudiness, humidity, or possibility of storm in the next few days. Weather is localised, say, it’s a hot and cloudy weather in one part of the country and dry and windy on the other part.

1.1.1 What are the factors that influence weather?

Before we try to understand the factors that influence weather, we must understand what the components that describe a weather conditions are? Is it the rains, or the air temperature or both? The answer to this question is not so easy, and it’s a bit complicated. There are many components that constitute weather. Weather components include rain, cloud cover, sunshine, winds, hail, snow, sleet, storms, thunderstorms, heat waves and many more. These components are sometimes referred as weather parameters or climate elements. Each of these components define weather patterns of a particular area. These components determine the status of local atmospheric conditions. Again, as a basic definition, weather is the state of the atmosphere and majority of weather phenomena occur in the lowest layer of the atmosphere, called as the troposphere. Does it mean that ground conditions such as the topography, water bodies and vegetation of a particular area has nothing to do with it? No, it is not so. The state of the atmosphere is subjected to various processes taking place not only in the atmosphere but also in the ocean, the sea-ice, the vegetation, etc. Weather parameters or the components of weather form a sequence of events, and the influences are far reaching and they do not remain solely in the atmosphere. For example, terrestrial radiation impacts the air temperature, air pressure and humidity. The terrestrial location also influences the cloud formation. The clouds may or may not turn into precipitation depending on the outcome (cloud or rain), which is by and large governed by troposphere. Likewise, a lack of precipitation affects not only weather conditions, but also soil moisture conditions that may result in lowering of water levels (ground water table) in soil. Wind speed and direction are governed by the atmospheric pressure and air temperature. So, all these parameters or components are interrelated and the weather conditions are the outcome of their interactions. Therefore, we can say that, the three main components of weather are temperature, precipitation and solar radiation. These components are influenced by different factors.

19.1. Remedies to Combat Unemployment in Nigeria

(a) Rural development

One way of stemming the rural-urban drift, and thus control the resulting unemployment in our urban centers, it for the government to develop the rural areas. Not only should amenities be provided, but jobs should be created in the rural areas to stem the exodus. Fortunately, the Babangida administration seemed to have realized this with the huge amount allocation for the development of rural areas in the 1986 and 1987 budgets.

(b) Population control

Government must intensity the effort to control population growth Nigeria already has a huge population and with an estimated growth rate of about 3 percent annually, this can only compound the unemployment in the face of inadequate resources. It is therefore advocated that the government should renew the family planning campaign to check the population growth.

18.1. Basic for Government Intervention in the Economy

One of the most powerful arguments to justify government intervention in the economy in the economy is the so-called concept of market failure. In a typical free enterprise system where demand and supply forces operate, the efficiency which results only relates to economic welfare. The social cost implications of economic activities tend to be ignored. Governments therefore intervene in the economy with the social welfare objective in mind. One popular way by which governments have intervened in the economy is through ownership of particular industries or outright nationalization of some private enterprises. The advantages usually claimed for such an action are as follows:

17.1. The Nigerian Unemployment Milieu: Control Measures taken by the Government

At this juncture, the little efforts that have been made by the government to control unemployment to an extent shall be examined. Records from the Central Bank of Nigeria (1987), show the following efforts made by the government:

1. Youths Empowerment/ employment and skills programme. This was done in terms of provided minor jobs or ‘white-colar’ jobs.

2. Agricultural programmes such as the ‘Operation Feed the Nation’ by the Obasanjo Military Administration.

3. Provision of small scale industries and graduates employment.

4. Special public works (which were temporary). Some of these efforts are still in place while others are forgotten. For example, on the pages of the Businessday Newspaper, on August 4th (pg 13), 12th (pg 49), 21st and 27th, 2009 were the following headings revealed:

16.1. Overview of Medium and Small Enterprises (MSE) Growth

In most developing countries, MSEs constitute the vast majority of firms, generating a substantial share of both overall employment and output. Given their significant economic role, one might expect MSE growth to drive overall increases in output and income levels. In many cases, however, their largest economic contribution appears to be one of maintaining, rather than generating new, employment and income for the poor. At an aggregate level, MSEs demonstrate impressive growth, 3 especially when compared with larger firms. However, many individual MSEs grow slowly or not at all, in some cases, due to a conscious decision on the part of the business owner. Overall growth rates are often fueled by the rapid expansion of a narrow group of highly performing MSEs. In dev e loping as well as in developed countries, there appears to be a small group of “gazelles”, firms that outperform their peers and drive aggregate employment and productivity growth for the small business sector. Why do some MSEs expand rapidly, while others stagnate? What factors account for the wide variation observed in MSE growth trajectories? This paper explores a wide array of specific factors, but it is first useful to consider a broader conceptual frame work of opportunities and capabilities. Clearly, opportunities for profitable business activities shape the ability of an entrepreneur to expand his or her firm.

15.1. General Barriers and IB Strategies to Overcome

There are extensive barriers when it comes to doing business with people at the base of the pyramid. This is because of the market inefficiencies and high transaction costs that can render businesses unprofitable, particularly in the short run. For instance, customers in remote rural areas are hard to reach as the necessary infrastructure is not available. General barriers to IB models include:

• Shortages of adequate infrastructure such as roads, energy, water etc., particularly in rural areas and urban slums.

• The need to create a market (i.e. encourage demand): many goods and services are known as ‘push’ products (e.g. waste management and preventive healthcare). It is necessary to raise awareness about them in order to stimulate demand; new distribution channels must also be created.

• The lack of knowledge and skills among the poor, to act either as clients or as suppliers and employees.

• Complex or hostile regulatory or legal environments, affected by weak institutions and insufficient enforcement of rules and contracts. IB models overcome these barriers through innovation and by employing additional, targeted measures. Indeed, the strategies they use to overcome barriers to doing business with the BoP are one of the main defining features of IB models. These measures can be categorised as follows.

14.1. Characteristics of Social Entrepreneurs Compared to Corporate Entrepreneurs

Prior research has found many parallels between social and commercial entrepreneurs when it comes to personality and behavioural traits (Drucker, 1989; Gitman & McDaniel, 2008; Gordon, 2006). There are some essential personal characteristics of these entrepreneurs that contribute to the success of the venture. A recent empirical study conducted by Sharir and Lerner (2006) identifies eight variables that contribute to success of a social venture. Out of these eight variables, five are directly related to the qualities of the entrepreneur, namely, the entrepreneur’s social network , commitment , previous management experience, ability to integrate the vision and to establish strategic alliances . Similarly, a study of the characteristics of social entrepreneurs in the United States found that social entrepreneurs are more likely to have high social capital (Ryzin, Grossman, DiPadova-Stocks & Bergrud, 2009). Although such studies of the personal characteristics of social entrepreneurs provide useful information about the leadership and organisational skills of such individuals, they do not explain the essence of these traits, why they are important and how social entrepreneurs use them to achieve their social mission and create and sustain social change. More research is required to understand what values, motives and behavioural repertoires distinguish a social entrepreneur from a corporate entrepreneur.

13.1 Internal and External Factors Affecting Small and Medium Enterprises

Margi Lévy and Philip Powell argued that growth is determined by a combination of the entrepreneur, strategy and the firm organization. The author also defined key influences on SMEs growth, internal factors that reveal how decisions and features effect the growth of a firm.

(a) Entrepreneurial influences

A firm’s growth is dependent on the managerial knowledge (Macpher son & Holt 2007, 172-192). Training is crucial for the productivity and quality as well as it influences the effectiveness, efficiency and motivation of the employees (Thassanabanjong et al., 2009). The SME owner has considerable personal influence over a firm’s strategies, tactics and operations to engage in decision process across the firm.

As a result, although a flat, informal organizational structure is likely to exist, decisions making tends to be quite centralized around the owner. The entrepreneurs’ personality and behavior are to be causal factors for or against growth - orientated achievement. It is characteristic of small business that power decision are centralized at the level of owner - manager, so his or her personality, skills, responsibilities, attitude and behavior will have decisive influence on business strategy. (Levy and Powell, 2005).

Market competition has a larger affect for SMEs chance of survival and uncertainty is high as most of the smaller companies tend to have smaller share of the capital. This leads SMEs to have one or two major customers and are do not have big influence on prices. Larger companies with higher market share usually determine prices. (Levy & Powell, 2005).

12.1. Practice of SMEs in Africa-Critical Review

Previous studies in Kenya have focused on the role of entrepreneurship education in job creation, enterprise management and economic development (Simiyu, 2010; Mwangi, 2011; Warren, 2011); hardly any have addressed the process of delivering entrepreneurship education. Research provides new knowledge to guide educational practice, by making an initial foray into the teaching of entrepreneurship education in Kenya. The envisaged entrepreneurially empowered TTI graduate is a product of the training function. This book examines factors which affect implementation of entrepreneurship education programme in TTIs in Kenya. The variables investigated were teaching methods, assessment methods, teacher’s network, and availability of training resources. The findings show that teachers do not accord entrepreneurship education t he appropriate pedagogical approach that it deserves; they seem resigned to using ineffective traditional pedagogies. Meanwhile, the subject is inadequately resourced by TTI administrations. The results of this research invite the attention of entrepreneurship educators, practitioners and stakeholders to employ effective strategies for dev eloping entrepreneurial key competencies in TTI trainees.

11.1. Support for Start-Up Finance

Access to finance for start-ups is always difficult due to the problem of asymmetric information. Start-ups lack the kind of financial history which banks use to infer the pay back behaviour and the business capacities of the entrepreneur. Innovative start-ups face the additional problem that it is difficult to assess the viability of their business ideas or the prospects of the markets. In addition, banks and other potential investors often decline to get involved when the relatively small amount of capital requested by a new business is out of proportion with the efforts that the investors must make to screen and evaluate the start-up project.

These problems are even greater for companies engaging in IB models, as doing business with the poor is usually riskier - or perceived as more risky - due to BoP customers’ low ability to pay and the greater vulnerability of value chains. Support for start-up finance is therefore essential. Local IB start-ups often lack funding at all stages of the start-up process: the idea stage, when business opportunities are identified, the seed stage, when the market is assessed and the business model developed, and the start-up stage, when the company is formally set up and all the necessary equipment is procured. Different kinds of financial support will be necessary at all stages.