eChapters

INTRODUCTION

Carbon dioxide gas is fundamental to sustaining life on earth for two reasons (i) it is a source of C for photosynthesis, and (ii) it acts like blanket in atmosphere that keeps the earth warm. Molecular CO₂ absorbs short wave solar radiations and release them as long wave infra red radiations. An atmospheric concentration of 300 ppm is adequate to support life on earth. CO₂ accounts for about half of the greenhouse effect. The natural concentration of green house gases (GHGs) has been essential to life on earth, creating the average temperature of 15ºC. Without the naturally occurring green house effect, the average temperature would be minus 18ºC. CO₂ concentration has now reached 400 ppm. If present trends continue then CO₂ levels would reach 600 ppm in 2100 and 1300 ppm in 2200 and level off at 1800 ppm in the year 2400 (Harvey and Danney, 2000). With increasing CO₂ concentration the amount of solar radiation absorbed by atmosphere would increase and make earth warmer. The higher atmospheric temperature can affect global hydrological cycle and alter the distribution and productivity of terrestrial biota. This can have devastating consequences for human life as each 10C increase in temperature, vegetation zones may change dramatically, moving toward the poles by 200-300 km. Further, each 1ºC of global warming will also increase water evaporation, leading to about 2% greater mean global precipitation.

INTRODUCTION

Phytotoxin literally means “plant poison”; it may refer to any toxin produced by a plant. Phytotoxins generally have allelopathic effect. Allelo-chemicals when added/released to substratum may be directly or indirectly harmful or beneficial to the growth and development of the associated vegetation or to the source plant itself. The definition of allelopathy accepted by the International Allelopathic Society is; “any process involving secondary metabolites produced by plants, algae, bacteria and fungi that influence the growth and development of agricultural and biological systems” (Torres et al. 1996). Allelo-chemicals are defined as bio-communicators suggesting the possibility of active mixtures, because of the findings in which single compounds are not active or are not as active as a mixture (Macias et al. 1998). 

Introduction

Plant pests have been a part of the man’s environment, since ages. Traditional agriculture which included diverse crops and indigenous crop management practices provided little opportunity for the pests to build up and spread rapidly (Smith and Allen,1954). Crop production is constantly threatened by increasing difficulties in controlling insect pests, which are a major impediment to improved livelihoods of the poor farmers. However, in the quest for increasing food production for the growing population, use of pesticides became a norm in crop management. Pesticides became an integral part of the process owing to losses from weeds, diseases and pests reducing the harvestable produce. Use of pesticides along with high yielding varieties, irrigation and improved seed did result in increased productivity. But the rampant use of these chemicals, under the adage, “if little is good, a lot more will be better” has played havoc with human and other life forms.

Introduction

Worldwide damage due to insect pest attack accounts for 15 per cent crop losses, despite the use of insecticides which represents over US $100 billion (Krattiger, 1997). The annual cost of insect control itself amounts to US $8 billion, thus warranting immediate and economical control measures. The crop varieties developed in the past 30 years were high yielders, but unfortunately had poor storage characteristics and were highly susceptible to pest damage. Insect-pests are capable of evolving to biotypes that can adapt to new situations, for instance they overcome the effect of toxic materials or bypass natural or artificial plant resistance, which further confounds the problem (Roush and McKenzie, 1987). Under these circumstances, provision of food to the rapidly expanding population has always been a challenge facing mankind. This problem is more acute in the tropics and sub-tropics, where the climate provides a highly conducive environment for a wide range of insects and necessitates massive efforts to suppress the population densities of different pests in order to achieve an adequate supply of food. In developing countries, the problem of competition from insect-pests is further complicated with a rapid annual increase in human population (2.5-3.0 percentage) against a meager 1.0 per cent increase in food production. In order to feed the ever expanding population, crop protection plays a vital and integral role in the present day agricultural production to minimize yield losses. Currently, the crop protection practice in agricultural systems relies exclusively on the use of agrochemicals, although a few specific cases do exist, where inherent varietal resistance and biological control have been successfully employed. The exclusive use of chemical pesticides not only results in rapid build-up of resistance to such compounds, but their non-selectivity affects the balance between pests and natural predators, and is generally in favour of pests (Metcalf, 1986).

Introduction

Plant parasitic nematodes occur wherever plants grow. These nematodes are referred to as plant pathogenic when they cause crop losses by direct injury to roots, stems, leaves and seeds. A large number of plant parasitic nematodes have been found associated with fruit crops in all over India but pathogenisity has not been proved for all. Most of commonly occurring nematodes belong to genera Meloidogyne spp., Pratylenchus spp., Rotylenchulus spp., Hoplolaimus spp., Tylenchulus spp., Xiphinema spp., and Radopholus spp. etc. The nematodes damage the crops not only by feeding on plants but also by interacting with various other organisms like fungi, bacteria and viruses etc. Estimated overall average annual yield loss of the world’s major crops due to damage by plant parasitic nematodes was 12.3%. Estimated annual crop losses in India have been accounted to Rs. 242.1 billion. The crop losses due to nematode pests are not only in the form of reduced plant growth and yield but are also in the marketable quality of the produce.

Introduction

The contribution of agrochemicals in improving food security and human health cannot be undermined. They are, however, like a double-edged weapon; their indiscriminate use could result in a serious threat to the sustainability of the agricultural production system and human health. Though their long-term effects on environment and human health are yet to be fully understood, the short-term adverse effects of their indiscriminate use became apparent soon after their invention during the World War II. Many insect pests have developed resistance to chemical pesticides, and a number of beneficial insects that are natural enemies of the pests have disappeared. Realizing these threats, the scientific community has been proactive and developed safer alternatives using flora and fauna as substitutes for chemical pesticides. These alternatives are claimed to be as effective as chemical pesticides. Experimental evidences indicate that these provide effective protection against pests when used in conjunction with other methods of pest control, including chemical pesticides. The strategy is often referred to as Integrated Pest Management (IPM). Since the adoption of IPM as a cardinal principle of plant protection in 1985, India has devised and implemented many IPM programmes encompassing research, extension and education with the objective to reduce the use of chemical pesticides, improve farm profitability, conserve environment and reduce adverse effect of pesticides on human health. Their effect is revealed in considerable reduction in pesticide-use, particularly during 1990s. The purpose of this paper is to provide a perspective on the IPM with emphasis on food security and safety.

Introduction

Majority of the commercially important freshwater prawns belongs to the genus Macrobrachium of family Palaemonidae. Among the commercially important freshwater prawns of India the most important cultivable species at present is the giant freshwater prawn Macrobrachium rosenbergii due to its superior cultivable attributes such as fast growth rate, large size, wide range of salinity tolerance, hardiness and compatibly to grow with carps. The species enjoys good consumer preference and domestic as well as export market demand. Freshwater prawns are cultured in freshwater or low saline brackish water (salinity <10 ppt) and can be cultured either alone (monoculture) or in combination with fishes such as carps, tilapia and milkfish (polyculture). Freshwater prawn culture can be carried out in earthen ponds, cement cisterns, in pens or in cages. However, most of the operations are being carried out in earthen ponds.

Introduction

Market intelligence is a basic requirement for attaining global trade competitiveness in agriculture and allied sectors. In a free market economy, a commodity’s current price and expected future price have consequences on its future supply as the entrepreneur’s production plans are accordingly changed. Additionally market intelligence on non-price issues like changes in consumer perceptions, traceability and quality related issues of HACCP is also equally important. This can guide the farmers in deciding the quality and the quantity of a commodity to be produced for particular target market/market segment. Market analysis and quantity that is likely to be in demand and price forecasts for fish are important to producers for rational production planning and for processors/exporters for taking right marketing decisions. Domestic and international input suppliers, bankers, insurers and policy analysts need market intelligence to estimate the requirements of fishers at macro-level for their advance planning.

Introduction

Linear programming (LP) is one of the most widely applied operation research techniques and owes its popularity to George Dantzig’s simplex method (Danzig 1963). It is an important field of optimization for several reasons. Many practical problems in operation research can be expressed as linear programming problems. Linear programming is heavily used in microeconomics and business management, either to maximize the income or minimize the costs of a production scheme. Some examples are food blending, inventory management, portfolio and finance management, resource allocation for human and machine resources, planning advertisement campaign etc.

In our economy, there are limited resources at our disposal. Our problem is to make such use of these resources to yield maximum quantity of production or to minimize the cost of production. Therefore, there arises the question of Linear Programming that is defined as a mathematical method of calculating the least cost combination of the factors of production, when there are many possible alternative combinations available to an enterprise.

What are Chordates?

The animal kingdom is divided first into several major animal groups called phyla: singular phylum. There are approximately so animal phyla. The last major groups of the animal kingdom are known as phylum chordate it was created by Belfour, in 1880. The name of this phylum is derived from two Greek words, the chorda- meaning a string or cord and ata- meaning bearing. The reference is to a common characteristic feature in the form to a stiff, supporting rod – like structure along the back, the notochord (Gr – noton – back, L-chorda-cord). This is found in all the members of the phylum at some stage of their lives. Chordates are animals having a cord are “notochord” or “Invertebrates” since they have no notochord or back bone in their body structure.

Phylum chordate is the largest to the deuterostiome phyla. It is the highest and the most important phylum comprising a vast variety of living and extinct animals including man himself most of the living chordates are the well known familiar vertebrate animals, such as the fishes, amphibians, Reptiles, birds and mammals.

Three fundamental characters of chordates:-All the chordates possesses three outstanding unique characteristics at same stage in their life history. These three fundamental morphological include,

• Type of Aquatic weeds

• Different control method

• Advantage and disadvantage of Aquatic weeds.

Aquatic weeds are those unwanted and undesirable plants, which reproduce and grow in fast in water bodies. They are more harmful them beneficial for fish culture. Excessive growth of aquatic vegetation prevents effective utilisation of water and reduces productivity because they utilize the nutrients and also prevent the sunlight to read the deep part of the water body. This excessive growth restrict the living space of fishes, resulting into less production. The decay mass of these pollute weeds prevent the growth of more useful microorganisms. And disturb the food web and food chain and equilibrium of physico-chemical qualities of water. Liberation of toxic substance and waste decomposition of water body is most effective so it is necessary to identify and control them. It has the primary problem of management of Inland fishery cultures.

Aquatic plants grow on extremely wet soil and where water is available to plants in abundance such as ponds lanes river banks etc. or those plants which grows and found in the nearby water body or in water body. These plants are called as aquatic weeds because these are not attend the larger size and act as the weeds which is found in water so these are called as aquatic weeds.

• Fish cum-poultry farming.

• Fish cum-duck farming.

• Fish cum-pig farming.

• Fish cum-paddy farming.

A) Fish Cum-poultry farming

Inland fish culture in conjunction with poultry rearing is a compatible business and can provide a readymade fertilizer for fish pond. In a larger sense fish and poultry are mutually complementary the former provides fish meal a protein rich poultry feed and the later is droppings which acts as fertilizers for plankton production to serve as natural proteinous fish feed. Fish meal is recognized as perhaps the choicest poultry feed. In an integrated fish cum-poultry farm, birds have to be housed in deep litter of battery system in which the pen flora is covered with hay. The floor of the pen is covered with chapped straw dry leaves, hay broken up groundnut shells maize straw and saw dust. Each bird should have about 0.3 m² space to live on the deep litter flooring bird droppings falling on the litter react with the flooring organic material. The litter has to be periodically churned for aeration and maintenance of hygienic conditions.

Introduction

The status of women in India has been subject to many great changes over the past few millennia. From equal status with men in ancient times through the low points of the medieval period, to the promotion of equal rights by many reformers. The history of women in India has been eventful. In modern India, women have adored high offices in India including that of the President, Prime Minister, Speaker of Lok Sabha, leaders of opposition etc. The incumbent president of India is a woman but the same vast majority of the women suffer from the great discrimination and even the basic human rights are denied to them.

Introduction

Computerization in education is perpetual need of today. Computers store large quantum of data that can be retrieved and used wherever necessary. They can also be used as an interactive media in transfer of technology system, which aids farmers and extension workers to access in formation of their need and to communicate with each other. Positive advantages in web education over distance learning process are that farming community can access it from any part of the world. Web education has also the added advantage of updating its data base on weather conditions, market situation in hourly basis which is not possible distance education as the process need a long time with regard to the availability of human resource and static course material to be developed for a particular time frame. The distance learning process being conventional in nature and also in place for quite a long years has abundance of resources and infra structural facilities however in web education, the professional resources are less in number and still arm journalism is yet to gain popularity among them. So web based interactive knowledge network system in transfer of technology is a present need which has to be addressed with due attention to improve the quality of existing communication system.

Introduction

SWOC analysis is a strategic planning method used to evaluate the Strengths, Weaknesses, Opportunities, and Challenges involved in a project or in a business venture. It involves specifying the objective of the business venture or project and identifying the internal and external factors that are favorable and unfavorable to achieve that objective. A SWOC analysis must first start with defining a desired end state or objective. A SWOC analysis may be incorporated into the strategic planning model.

• Strengths: characteristics of the business or team that give it an advantage over others in the industry.

• Weaknesses: are characteristics that place the firm at a disadvantage relative to others.

• Opportunities: external chances to make greater sales or profits in the environment.

• Challenges: external elements in the environment that could cause trouble for the business.

Introduction

The extension approaches followed in agricultural sector during past decade is reoriented in various occasions and new system of approaches were implemented. The present day orientation is shifting the efforts of extension from production orientation to profit orientation. Under these circumstances, the key factor for success will largely depend upon the extension service provider’s orientation and farmer’s capacity to absorb new knowledge of improved practices and technology. In order to orient officials towards this change HRD is essential. This will help them to impart required competencies in knowledge and skill such as technical, organisational, managerial, communication and business skills.

The present day extension approach i.e. ATMA focusing towards block level planning, farmers participation in planning and implementation of various schemes, group approaches, importance to agri and allied aspects are the major focus of ATMA. The Tamilnadu government in the year 2007 reorganised the extension system in to twotier at district level with the major focus to block level. In each block Agricultural Extension Centres (BAECs) were established which houses for agriculture, horticulture, marketing, agri. engineering departments.

Introduction

Cassava is an important tuber crop in India grown in 2.7 lakh hectare area with a production of 71 lakh tonnes. The average yield of tapioca is 22 tonnes per hectare. Cassava is a richest source of starch (25 to 35%) mainly processed for starch and sago. Cassava is an industrial crop of Tamil Nadu occupies 32.97% of the area and 45.98% of the production in India. (Edison et al 2006). In Tamil Nadu major traditional tapioca growing districts are Salem, Namakkal, Erode, Cuddalore, Dharmapuri and Kaniyakumari mostly as rainfed. Among the districts Salem District stands first in area (27000 ha) and with the production of 10.475 lakh MT(Anonymous, 2006).

Introduction

India now emerged as the world’s second largest producer of fruits, vegetables and tea holding a share of 10 percent. The production base of horticultural crops has been expending since independence (Chadha, 2009). But as a controversy to the previous statement there is a clear indication about the declining farm sector performance-in addition to its deleterious economic ramifications often causing large scale rural distress which often ends up in farmer suicides (Sundaresan, 2009). This distress conveys much on the economic rationale ruling the agri and rural domain for its incompatibility in the changing market environment. The identified major problems faced by farmers in the present scenario were non-availability of information about marketing services including availability of crop specific markets, existing demand of a commodity and daily market price for their produce which can be broadly categorized under lack of market-led extension services.

Introduction

Indian agriculture contributes to 25 per cent of the National Gross Domestic Product. As per Census of India, 2001, India’s total population was 1,028.6 million and the percentage of decadal growth of population during 1991- 2001 was 21.34 per cent. Thus, the main challenge is to produce enough food for increasing population.

Many new agricultural technologies and improved practices are being developed in agricultural research stations. Effective communication of these agricultural innovations to millions of farmers in rural area is essential to bring about accelerated agricultural development. The impact of demographic pressure on reducing farm size further on the one hand and the need for longer or optimum sized farms to take more advantage of modern technology on the other hand would bring into sharper focus the growing contradiction in the farming sector.

Introduction

Soil, water and vegetation are three basic natural resources. The survival of God’s creation depends upon them and nature has provided them as assets to human beings. The management of natural resources to meet people’s requirements has been practised since the pre-Vedic era. Farmers were ranked high in the social system and village management was in their hands. Over-exploitation of natural resources by growing population resulted in various severe problems. Destruction of vegetation has resulted in land degradation, denudation, soil erosion, landslides, floods, drought and unbalanced ecosystems. A balanced ecosystem is an urgent need.

There is an increasing realization throughout the world, about the state of our environment, caused by over-exploitation of natural resources for economic development. Resource exploitation in the developing world has largely been geared to meet the very basic needs of food, fodder, fuelwood and shelter of a large section of deprived societies. On the other hand, developed parts of the world have largely concerned themselves in trying to maintain and accelerate the already very high levels of resource consumption that they have achieved for a much smaller segment of the world’s population, based on an early initiative taken and advantage gained through industrialization. Natural resource base has often viewed as limitless by the industrialized world either due to a myopic view of the future or because of their immense faith in technology being able to substitute for the natural resource capital. This faith in technological quick-fixes for world’s problems linked with over-consumption is still prevalent.