eChapters

INTRODUCTION

The origin of fish culture in India probably dates back to 2000 years. Possibly, fishery activity started when the human settlement moved away from the riverbanks to the hinterland. As the days went by, the Indian fish farmers practice their own indigenous technology as a common practice through natural resource management (National Commission on Agriculture, Gov. of India, 1976). The close and intimate observation of farmers through their age-old practices has developed the expertise of acquiring knowledge in aquatic ecosystem in particular. Admittedly, the multifarious knowledge and skill possessed by local people can substantially contribute to productive efforts and endeavors (Dasgupta, 1993).

INTRODUCTION

The enemies of plants have been harming the organized agriculture ever since man started depending on plants for food. Fossil evidence indicates that plants were affected by disease since 250 million years ago. Conditions of food shortage and famines have been created by these enemies of plants. Naturally, the man had been obvious of their presence and proposed explanations and methods of combating them according to the knowledge available at that time all over the world. It is not true that attention to plant diseases was first given in the western countries. In the ancient Indian literature many plant diseases and their remedies were mentioned.

INTRODUCTION

Assam is a heartland of indigenous groups. Since hundreds of years, many indigenous groups have been living in the state, maintaining their originalities in every sphere of life with difficulties. The tribal-indigenous groups constitute almost 12.4% of the total population of Assam. (Sentinelassam.com). Fishing is one of the major livelihood option of many indigenous fishers as the state is blessed with huge water resources with about 3.91 lakh hectare of water area in the form of rivers, beel, derelict water bodies and ponds and tanks. Besides swamps and low-lying areas, two major rivers and their tributaries have a high growth potential for fishing and could play a pivotal role in the socio-economic development and employment generation in the state. Indigenous fishers have developed a close and unique connection with the water resources and its environment in which they are depended for generation to generation for their livelihood. They have generated unique system of knowledge, innovation and skills relating to the uses and management of fishing activities. Over centuries, people have learnt how to get food and to survive in different environment. Farmers are very keen to observe the problems arising during fishing and seek solutions to adjust to their local environmental conditions. They continuously adapt and manage their fishing systems and in this way, they develop a rich storehouse of practical knowledge on their situation.

INTRODUCTION

Northeast India comprises the contiguous seven sister states.viz., Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland and Tripura and the Himalayan state of Sikkim. The Northeastern states of India are blessed with diversified fish fauna which assumes special interest due to the fact that the region is grained by two important drainages viz., Brahamaputra-Barak and Chindwin Irrawaddy. (Gurumayum and Choudhury, 2009). Riverine fisheries resources of Northeastern States comprise of 19,150 km of streams and rivers. Except the Brahmaputra and Barak Valleys in Assam and Imphal Valley in Manipur, the Northeast mainly comprises of Hills and Mountains which form 65% of its territory (Suguman, 1998).

INTRODUCTION

Fish is a dependable source of animal protein in developing countries like India. In recent years, with the rapid development of the aquaculture enterprises, the infectious diseases caused by fungus, bacteria, virus and parasites became more severe, resulting in huge economic losses. Due to certain unavoidable problems for diagnosing and treating diseases, losses are being born by the poor fish farmers of the country.

The issue is more relevant to rural area like north-east India, where soil and water are highly acidic due to the high content of ferrous ions and high rainfall and their management needs high inputs. The situation gets shoddier when the farmers do not get the access to water and soil laboratory to test their pond samples. It is very hard for the rural farmers to monitor their culture pond condition without any scientific tools and technical knowledge. Moreover, stresses due to over-crowding, wide temperature fluctuations, cold stress, global warming, microorganism, pesticides, insecticides, chemicals, contaminants etc.

INTRODUCTION

The medicinal values of plants are known since prehistoric times. Interestingly, 13000 BC old drawing on Lascaux caves in France suggests that humans were using plants for medicinal purposes. Ancient Egyptians chewed willow bark to relieve fever and headaches; and thousands of years later, scientists discovered that the bark contains salicylic acid- the active ingredient in aspirin. History reveals that in most of the countries natural products including plants, animals and minerals have been the basis of treatment of diseases both in human and veterinary medicines.
 
Plants as a source of medicine has been an ancient practice and is an important component of the health care system in India. The health management of people and domestic animals is based partially on the exploitation of natural resources, which needs proper documentation and research.

INTRODUCTION

The North Eastern Region of India comprises of eight states, viz., Assam, Arunachal Pradesh, Manipur, Meghalaya, Tripura, Nagaland, Mizoram and Sikkim. These north eastern states are home to myriad tribals and several ethnic groups. Most of the people of the north-eastern region of India belong to the Mongolian race and the food habit of the region is fairly similar with that of South-East Asian countries. Fermented foods form an intrinsic part of the diet of these people. Fermentation has been an age long traditional practice of preserving various food products in the region. These fermented products are used as condiments in the preparation of various traditional sauces, strews and dishes (Saisithi, 1994).

INTRODUCTION

In the emerging global knowledge economy, a country’s ability to build and mobilize knowledge capital is equally important for sustainable development like the physical and financial capital (World Bank, 1997). The basic component of any country’s knowledge capital is its indigenous technical knowledge (ITK). ITK is the social capital of the local people, their main asset to invest in the struggle for survival, to produce food, to provide for shelter or to achieve control of their own lives. It is the unique, traditional, local knowledge existing within and developed around specific condition of men and women indigenous to a particular geographical area (Ghosh and Sahoo, 2011). It helps to increase the sustainability of development efforts because of its integration process with mutual learning and adaptation, which in turn contributes to the empowerment of local communities.

INTRODUCTION

Fish are one of the main exploitable resources of the aquatic ecosystems that provide a cheap source of protein which help solving the problem nutritional security particularly NE region of the country. The rapid development of fishing technology in India during the recent years has paved the way for increased production availability of new synthetic materials, evolution of new designs of fishing crafts and gears and avoidance of ignorant harmful fishing techniques etc. It is to be taken into account that any developmental activity adopted should also be base rooted in the objective of uplifting the economy of the fishing communities. This implies that the improvisation of the existing tools and techniques and introduction of new ones to enhance fishing efficiency need a careful study of the traditional infra-technologies. Further selection of fishing methods and gear are influenced by various factors such as physiographic of the water body, nature of fish stock, characteristics of the material from which gear are fabricated and standard of living. Therefore, variation in application of fishing devices can be observed in different type of water bodies, which have characteristic of their own due to unique nature of the water resources of the region.

Introduction

North East India constitutes the states of Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Tripura and Sikkim which reflects ecological and cultural contrasts between the hills and the plains. It is one of the most biodiversity regions in the world, with more than a hundred and fifty tribes forming a melting pot of variegated cultural mosaic of people and races constitute a vital component in this region (Dutta and Dutta, 2005).
 
More than 70% people of the region are engaged in agriculture while rice is the staple food crop (Bhattacharjee and Ray, 2010). The farmers from different ethnic diversity of the region have developed their own systems of cultivation of various crops (Islam et al. 2004). These indigenous traditional knowledge systems are quite endemic to this region (Deka et al. 2006).

INTRODUCTION

Traditional knowledge is the knowledge, innovations and practices of indigenous and local communities around the world. Developed from experience gained over centuries and adapted to the local culture and environment, it is transmitted orally from generation to generation. It tends to be collectively owned and takes the form of stories, songs, folklore, proverbs, cultural values, beliefs, rituals, community laws, local language. Sometimes it is referred to as an oral tradition for it is practiced, sung, danced, painted, carved, chanted and performed down through millennia. Traditional knowledge is mainly of a practical nature, particularly in such fields as fisheries, health, horticulture, forestry and environmental management in general. Appreciation of the value of traditional knowledge is growing. This knowledge is valuable not only to those who depend on it in their daily lives, but to modern industry and farming as well. Many widely used products, such as plant-based medicines, health products and cosmetics, are derived from traditional knowledge. Other such valuable products include agricultural and non-wood forest products as well as handicraft. Traditional knowledge can make a significant contribution to sustainable development.

Cell culture has become one of the major tools used in the life sciences today. Viruses replicate only within the living cells. With the advent of cell culture technique, it has become easier to grow the viruses under in vitro condition (cell culture). Viruses are usually propagated in cell culture, embryonated hen’s egg, laboratory animals or natural hosts. In 1949, Enders, Weller and Robbins first reported that polio virus could be grown in cultured non-neural cells with the production of recognizable cytopathic changes. Although the cell culture technique has been evolved long back, it is only since the advent of antibiotics that cell culture became a matter of simple routine technique. Aseptic precautions are still essential, but the problems of contamination with bacteria, mycoplasma, fungi and yeasts can be checked by antibiotics and anti-fungal agents. The term in vitro literally means ‘in glass’ although today most cell culture is performed in or on plastic.

The cell is the unit of structure of all plants and animals. With increasing complexity of organization, masses of different cell types tend to become localized and to form recognizable patterns. An aggregation of cells forming a definite pattern is called tissue. A still higher level of organization, tissues aggregate to form organs. The animal cell is a highly organized structure. Plant cell is different from animal cell  by having a cellulose cell wall.  There are a number of well defined structures viz., nucleus, mitochondria, lysosomes, Golgi apparatus etc in the cell. Animal cells also have centrioles whereas plant cells contain plastids such as chloroplasts. The remainder of the cell is the cytoplasm.

The best environment for growing cells is similar to  the conditions what they experience in vivo. A number of various environmental factors affecting the tissues are :
 
    (1)    Temperature : In living matter, complicated chemical reactions are happened at comparatively low temperature.  In most of the mammalian and avian tissues the temperature  is 37^ºC to 38.5^ºC. If the temperature is enhanced to 45^ºC, cells are destroyed within  an hour but survive 12-24 hours at 42^ºC. It is applicable to most of the fibroblasts and epithelial  types of cells arising  from  mammalian tissues. Some of the mammalian cells ( human skin epithelial cells)  and amphibian cells  prefer lower temperature but fish tissue will not survive beyond 20^ºC.

Types of cells : Animal cells are usually defined by the tissue of their origin. On the basis of morphology, they can be divided into 5 types.

    1.    Epithelial cells : Epithelial tissues consist of a layer of cells which cover organs and line cavity. Example skin and the lining of alimentary canal. They grow well as single cell monolayer in culture.

    2.    Fibroblast cells : Connective tissue form the major structural component of animals. The tissue contains fibroblasts and most widely used cell in the laboratory. Fibroblasts are bound to the fibrous protein collagen in the connective tissue. They have excellent growth characteristics.

A finite growth capacity is a characteristic of all cells derived form the normal animal tissue. The cells pass through a series of age related changes before being incapable to divide further. The finite number of generations of growth is a characteristic of the cell type, age and species of origin and referred to as the “Hayflick limit”. The cells derived from embryonic tissue have a greater growth capacity than those derived from adult tissue.

A cell culture laboratory should allow the sterile handling of cultured cells with no or minimum level of contamination. The growth of bacteria and fungi is very high and no level of contamination can be allowed in animal cell culture. However, it is impractical to design a laboratory free from potentially contaminated microorganism. Further, it is possible to establish a laboratory with minimal risk of contamination. Several points should be taken into consideration while designing a new cell culture laboratory.

Once cells are obtained from a culture collection or isolated from animal tissue,, cells are put in the flask with growth medium. The cells are inoculated at a density of 104-105 cells/ml to get a concentration of 106 cells/ml or 105 cells/cm2 in a solid surface in 2-3 days because of nutrient limitation, accumulation of toxic metabolite or lacking of growth surface.

Cell culture medium : To grow cells in in vitro, environment should be as close as possible to in vivo condition. But a number of factors are important to grow cells in vitro namely substrate, temperature and medium. There is a number of ready made medium available commercially and made the cell culture work easier. Any successful medium consists of isotonic buffer solution containing inorganic salts, amino acids, vitamins, a energy source and various supplements. Usually serum or serum replacement is used as supplement.

Primary cells are often preferred to established cell lines as they better represent the cells in vivo in terms of activity and functions. On the other hand, there is significant difference between original culture and present culture and even between cultures of the same cells in different laboratories. The rate of growth increases and there is change in chromosome numbers of lines over the time. The differences in phenotypes can cause problems in comparison and interpretation of results. The advantage of cell lines are ease handling, grow continuously, large yield and readily available. Primary cell cultures compared to established cell line are more fastidious in their growth requirements because many cell lines are derived from tumour tissue and demonstrate reduced growth factor requirements.

Cell growth and cell passage : Different types of cells have different growth requirements but in all cases the surrounding medium must supply all the essential nutrients. The temperature, pH, osmolarity and humidity must be kept within limits. Again, toxic or inhibitory substances must not be allowed to accumulate. Serum, a source of macromolecular growth factors, is essential to the growth of many cell types. Anchorage dependent cells require nontoxic or biologically inert glass or plastic surface for attachment.

In may cases, it becomes necessary to send the cells from one laboratory to another laboratory within or outside the country. The ideal method is to fill the flask containing cells at log/exponential phase with growth medium, tightly close the cap, seal it with parafilm and tape and pack it properly with polythene containing tissue paper and cotton. The tissue paper and cotton is used to soak the medium in case of accidental breakage. The polythene containing tissue culture flask having the adherent cell sheet should again be packed with thick paper. Finally, it is to be kept in a wooden/metal box or container.

Vero (monkey, African green, kidney) 
Morphology: Fibroblast
Species:, African green monkey 
Tissue: Kidney

Properties: Virology, virus titration, virus replication, plaque assays, bacterial cytotoxicity

If the concentration of cells in suspension cell culture has reached to 7X10⁵ cells/ml, it is to be subcultured. Suspension cells are diluted to concentration of approximately 1X10⁵ cells/ml although it varies from cell line to cell line. So, to subculture into a 3 litre glass flask using 500 ml of suspension of cells, there is a need of 5X10⁷ cells. As the concentration of cells is 7X10⁵ cells/ml, there is a need of 71.4 ml of cells. Adherent cells are put in the culture flasks at a concentration of 5X10⁴ cells in a 25 cm² flask. For example, after trypsinization, the cells have been resuspended in 5 ml of medium and cell concentration is 1X10⁵ cells/ml or total number is 5X10⁵ cells. If one wants to put cells into two 25 cm² flasks each containing 5X10⁴ cells in 5 ml volume, there is a need of 1X10⁵ cells, which can be obtained from one ml of cell suspension (1X10⁵ cells/ml).

Small volume cultures are useful for experiments such as studying cell morphology, titration of viruses, plaque assay, pock assay, SNT and to compare the effect of agents on growth and metabolism. However, there are other application where there is a need of large number of cells such as extraction of DNA/RNA from cells, production of viruses for vaccine production and a number of products namely interferons, interleukins, hormones, enzymes, antibodies, glycoproteins etc. The large quantity of cells can be obtained by using a large number of flasks/bottles but it is tedius, labour intensive, expensive and there is a risk of contiamination. Although the unit processes are more cost effective and efficient, it needs some modification to overcome limiting factors such as oxygen depletion, shear damage and metabolic toxicity. There are a number of aberrations available to scale up cell culture described below.

There are a number of different cell lines derived from human and animals. With the dramatic increase in numbers of cell lines, the risk of intraspecies and interspecies cross contamination rises proportionally. It is particularly a major problem in laboratories where many different cell lines of human and animal origin are handled at a time. The purity of the primary cell or continuous cell lines and species of its origin should be checked on a regular basis to authenticate the cell line identity. In the absence of such monitoring, inter and intra species cell line contamination are likely to occur in the laboratory resulting in loss of investigator’s time effort and resources. The advantages of working with a well defined cell line free from contaminating organisms would appear obvious.

Early passage cell lines are relatively unstable and go through a period of adaptation to culture. However, between 5^th and 35^th generation (human diploid fibroblasts), the culture is fairly consistent although it varies from one cell to another cell. Finite cell lines should be preserved after adaptation but before senescence (getting older). Cells should be preserved to protect cell line instability, availability in case of contamination, incubator failure or accidental loss.

Cell culture contamination continues to be a major problem and a subject of great concern. Contamination may enter the cell culture system as physical, chemical or biological component of the environment and biological contamination represent the greatest threat as living organism metabolize and replicate. Replication increases the titre of the contaminant.
 
Physical contamination : Physical components of cell culture systems such as radiation, irradiation (UV light and fluorescent light), temperature extremes can cause reduced cell growth and cell death. To minimize the problems, incubators should be located where ambient temperature is relatively constant and no vibration (near centrifuge). Media and media components should not be stored in glass door refrigerators, next to radioisotopes, bench tops or outside the refrigerator or in the hood for prolonged period.

Enumeration of cells is essential to determine the multiplicity of infection, efficiency of plating and to obtain the specific number of cells for an experiment. The concentration of cells of a suspension can be counted using a haemocytometer. Each chamber is divided into a grid of nine large squares. Each large square is 1mmX1mm (area 1 mm²) and the depth is o.1 mm. The volume of each square is 0.1 mm³ or 10^-4 cm³. Since 1 cm³ is equal to 1 ml, the number of cells per ml of suspension can be obtained by multiply the average count per large square by 10⁴ and reciprocal of dilution factor. Dilution is made in such a way that one large square contain about 20-60 cells. The haemocytometer chambers should be filled by capillary action and cell clump are counted as one cell. A total count does not distinguish between living and dead cells. The number of viable cells can be determined by staining the cells with trypan blue or erythrosine B. In trypan blue staining cells appear as unstained whereas dead cells appear as blue.

Cell culture is the most convenient and widely used system for the isolation and propagation of many viruses. Either primary cell culture or established cell lines can be used to isolate the suspected viruses. One can normally get 10-100 virus particles per cell inoculated. Many details of the infection process are controllable to a high degree (including cell density, age, multiplicity of infection (M.O.I.), medium composition, cell type and length and temperature of incubation). Many cell types from different species can be susceptible to a particular virus and vice versa. For replication to occur, the cell type used must be permissive for a particular virus under study.

The most important property of a virus is its infectivity or ability to invade a cell and parasitize that cell to replicate itself. To measure infectivity, a titre is defined as the given number of infectious virus units/unit volume and an infectious unit is the smallest amount of virus that produces some recognizable effect in the host system. There are two basic types of infectivity assays (a) Quantal assays and (b) Quantitative assays.

Quantal assays do not measure the number of infectious virus particles present in the inoculum but denote a value for the virus titre where measurement is based on an all or none principle, CPE + or -, dead or alive etc. In the quantitative assays, the number of virus particles present in the suspension can be quantified.

The tentative diagnosis of viral diseases of livestock can be made by clinical symptoms alone. The clinical diagnosis is substantiated by the laboratory to obtain a precise, correct and prompt diagnosis. The success however depends on the collection of suitable materials in proper transport medium at a particular stage of disease condition and its dispatch to the laboratory in a manner that little or no alterations occurs in the specimen. This would facilitate the isolation and identification of the causative viral agents easily.

Bovine
 
1.    PPR    Eye, mouth, rectal swab in PBS on ice, 10 ml blood  in anti-coagulant at height of temperature, Prescapular lymph node, spleen, piece of intestine on ice, lung, liver, spleen, tonsil in 10% neutral formol saline solution.

Processing

On arrival in the laboratory, the specimens are processed immediately or refrigerated until processed. For inoculation into animal/cell culture/embryonated eggs (EE), swabs are shaken in fluid medium, faeces are dispersed in fluid medium and tissue specimens are homogenized in a high speed blender/pestle and mortar with the help of an abrasive like powdered glass or sand. Good quality hard sand should be properly washed in distilled water, treated with HCl, washed thoroughly, dried and sterilized before use. Generally the infective tissue is homogenized in a few ml of buffer usually having a pH of 7.2 to 7.3 to make about 10% tissue suspension. The suspension is centrifuged at about 1000g for 10-15 minutes to sediment the tissue debris and coarse materials.

Principle

The infectivity of a virus may be neutralized by specific antibody when they are mixed and incubated. In some cases, the addition of homologous or guinea pig complement to the mixture enhances neutralization, particularly when early antiserum is used. Serum must be inactivated by heating at 560C for 30 minutes to inactivate complement or to remove non-specific virus inhibitors. Serum-virus mixtures are inoculated into appropriate cell cultures, which are then incubated until the only virus controls develop cytopathic effects. Antibody by neutralizing the infectivity of the virus, protects the cells against virus destruction.

Early and accurate diagnosis of disease is of prime importance for both the successful treatment of the patient and in limiting the spread of disease in the community. It is in this context that immunodiagnostic methods are now being used extensively since they can be extremely sensitive and highly specific. Among the most successful methods are those utilizing labelled antibodies or antigens. Examples of these are immunofluorescence in which antibodies labelled with fluorescent dyes are utilized and radioimmunoassay in which antigens or antibodies are labeled with isotopes. Both of these procedures have proved to be of great value for particular purposes.

Precautions to be taken while working in the laboratory for personal safety and to prevent any hazards.
    1.    Be vaccinated against dangerous viruses viz., rabies and hepatitis B as persons can contract infection while working with these organisms.
    2.    Use eye protection viz., goggles, spectacles etc to avoid splashing microbes into the eyes. 
    3.    Do not rub eyes with contaminated hands or objects.
    4.    Do not eat or drink anything in the microbiology laboratory as it will contaminate the laboratory.

Introduction and History

Leguminosae/Fabaceae is a superfamily of dicotyledonous plants, which in species diversity is the third largest family of plants accounting for 5% of Earth’s plant biodiversity and make up for more than at least 1% of the total Earth plant biomass. Among these, legume grains and pulses having more than 20 to 30% lysine protein content are cultivated in 145 million ha of land in developing countries. This family is also characterized by presence of specialized tumor like structure formation (nodules) on roots (occasionally on stem as in Sesbania rostrata, Aeschynomene) that is inhabited by microsymbiont gram-negative bacteria (Rhizobium), engaged in fixing atmospheric nitrogen or symbiotic biological nitrogen fixation.

Introduction

Rhizobia and Frankia are soil bacteria that exhibit symbiosis with their particular hosts owing to their ability to understand the intricate signals excreted by the host roots. Rhizobia exhibit symbiosis with legumes and one species member of Ulmaceae family Parasponia andersonii while actinomycetes Frankia forms the group of nitrogen-fixing bacteria that live in symbiosis with a large spectrum of dicot plants distributed among eight families consisting of over 24 genera and around 200 species of angiosperms (Benson and Silvester, 1993) and are collectively responsible for 15% of the biologically fixed nitrogen in the world. This Frankia-woody tree or dicotyledonous plant interaction results in evolution of the actinorhizal plants and the symbiotic interaction is described between Frankia (actino) and plant roots (rhiza).

Introduction

Nitrogen-fixing cyanobacteria are the group of most primitive prokaryotes that have been observed in proterozoic era. Many Proterozoic oil deposits are attributed to the activity of Cyanobacteria, such as Gloeocapsomorpha. Small concentrically layered structures called pisolites are also the result of fossilized bacteria.

Introduction

Diazotrophs are phylogenetically diverse microbes spanning over various classes varying vastly on basis of physiological properties (Young, 1992), include various phototrophic microorganisms aerobic phototrophic Cyanobacteria (Vaishampayan et al, 2001), anaerobic purple-sulfur phototrophs like Chromatium, and green-sulfur phototrophs, e.g. Chlorobium, Rhodopseudomonas; chemolithotrophs Alcaligenes, Thiobacillus, Methanosarcina, Methanobacterium, Desulfovibrio or Azospirillum lipoferum and heterotrophic bacterial anaerobes (Clostridium), microaerophiles (Herbaspirillum), and aerobes (Azotobacter). Free-living aerobic nitrogen fixing bacterial genera found in soil include obligate aerobes as Azotobacter, Beijerinckia, Derxia, Achromobacter, Mycobacterium, Arthrobacter and Bacillus but the majority are microaerophilic (e.g. Azospirillum, Herbaspirillum) or facultative and obligate anaerobes (e.g. Klebsiella, Aerobacter, Desulfovibrios, Rhodospirillum, Clostridium, Erwinia).

Introduction

Increased population pressure, reduced length of fallow, deforestation and improper agricultural practices have led to widespread soil degradation in many parts of the developing world which has culminated in appearance of determinative manifestations of environmental damage in form of inadequate replenishment of soil nutrients and organic matter. Phosphorus is second major plant growth limiting nutrient and despite being in abundance in soil (organic and inorganic form), P deficiency is becoming critical in many soils throughout world as these soils have free available P concentration (generally) not higher than 10mM even at most soluble slight acidic pH (Arnou, 1953). Moreover, consistent P deficiency threatens to disturb the use efficiency of applying other nutrients. Hence to preserve the sustainability of agriculture it is foremost to rebuild soil fertility and maintain/improve the soil biodiversity to reap hiked current levels of productivity and farm income.

Introduction

Lithosphere, including the earth’s crust, is helpful in providing the base or medium for sustenance of most life processes and forms, interwoven in fine network interdependencies within themselves and the environment surrounding them i.e. ecosystems. Terrestrial ecosystem contains an important dynamic living matrix termed soil, which is critical for agricultural production and food security. Soil forms the medium for growth and maintenance of a variety of plant species while the plant roots in the soil represent a four dimensional region in space and time of profuse activity relative to the bulk soil, revolving around pH, nutrient, redox potential, and exudate gradients changing as distance from the root increases (Marschner, 1995). The soil region adhering the plant roots is being strongly influenced by the presence of these roots and is characterized by high rates of microbial population and activity and referred as rhizosphere (the soil adhering to plant roots).

Introduction

Vesicular arbuscular mycorrhizae are fungi that exhibit symbiosis with roots of higher plants. The term vesicular arbuscular is derived from characteristic structure i.e. ‘branched hyphae or arbuscles’ that are formed with in the root cortical cells and vesicles or ‘swollen lipid storing organs’ that occur with in or between them.

Introduction

India being a developing nation is trying to reach a balance in ever increasing population with marginal increase in crop production. There occurred a bigbang in crop production during the green revolution era however this also resulted in creation of infertile, barren lands with low chemical nutrient input responsive soils. Soil fertility is the major constraint among resource poor Indian farmers as lesser benefits are harnessed by use of newer agricultural protocols/tools/products viz improved varieties, productive technology from less fertile soils. There is dire need for looking for the alternative technologies of food or crop production to satiate the hunger of burgeoning Indian population. Today there is enormous emphasis on the conservation facets of soil fertility and crop productivity which are the instrumental philosophies in sustainable agriculture. Biofertilizers are the cost effective, ecofriendly and renewable resource of plant nutrients that could well supplement the use of already functional and popular chemical fertilizers for obtaining increase in crop yield without over hazardous impacts on various facets of soil chemistry, fertility and microbial diversity to attain sustainable agricultural system.

Introduction

Introduction of improved high yielding varieties of crop plants, use of modern agricultural practices coupled with essential control of pests of food and fiber crops have significantly contributed towards increasing the food production in green revolution era in India. Pesticide application forms the foremost limb in hiked agricultural food production and management practices. The production and post production management of crop yield requires increased use of pesticides.

Introduction

Soil forms the base of the lithosphere on earth and is a fundamental and irreplaceable versatile three dimensional dynamic system that supports majority of terrestrial plant and animal life on earth. This soil system contains mineral (sand, slit and clay forming basic soil structure) and organic matter as well as marginal air and water contents. The soil organic matter content of the soil system constitutes every fraction of matter in various stages of decomposition that once was associated with the body, body parts, exudates, tissues and cells of living organisms including plants, animals and microorganisms. It is the product of continuous cycling of the compounds synthesized by autotrophic plants among the three kingdoms viz microbes, plants and animals. The decomposition of the organic residues in soil is performed primarily by the resident soil microflora termed as microbial decomposers; though initially the larger and complex organic material is broken down, devoured upon, chewed, regurgitated and transformed into smaller bits by larger soil faunal forms (earthworms, beetles, springtails, and collembola, the macro (large) to mesofauna) on which soil microbial forms could act upon.

Introduction

Bioremediation can be defined as elimination, attenuation or transformation of polluting or contaminating substances by the use of biological processes, to minimize the risk to human health and the environment. Bioremediation of contaminated soil and water uses microbes (e.g. bacteria and fungi) to convert pollutants to harmless or more environmentally acceptable products and minimizes the risk to human health in a natural or managed process.

Climate change and variability are concerns of humankind. The recurrent drought and desertification threaten seriously the livelihood of over 1.2 billion people who depend on land for most of their needs. The global economy has adversely been influenced due to droughts and floods, cold and heat waves, forest fires, landslips and mudslips, icestorms, duststorms, hailstorms, thunder clouds associated with lightning and the sea level rise (Fig. 1). The year 1998 was the warmest and declared as the weather related disaster year, which caused hurricane havoc in Central America and floods in China, India and Bangladesh. Canada and New England in the U.S suffered heavily due to icestorm in January while Turkey, Argentina and Paraguay with floods in June 1998. In contrast, huge crop losses were noticed in Maharashtra (India) due to unseasonal and poor distribution of rainfall during 1997-98. The 1997/1998 El Nino event, the strongest of the last century affected 110 million people and costed the global economy nearly US$ 100 billion. A string of 16 consecutive months saw record high global mean temperature in 1997-98.

1. Introduction
 
The bryophytes are found everywhere in the world except in the sea. They grow on wet soil or rock, the trunk of trees, in lake, river and even in Antarctic island. The bryophytes are placed taxonomically between algae (Fig. 1) and pteridophytes (Fig. 2); there are about 24,000 species in the world. They are further divided into three phyla, Bryophyta (mosses 14,000 species, Fig. 3), Marchantiophyta (liverworts 6,000 species, Fig.4a,b) and Anthocerotophyta (hornworts 300 species, Fig. 5). They are considered to be the oldest terrestrial plants, although no strong scientific evidence for this has appeared in the literature. This hypothesis was mainly based on the resemblance of the present-day liverworts to the first land plant fossils, the spores of which date back to almost 500 million years. Among the bryophytes almost all liverworts possess beautiful cellular oil bodies (Fig. 6) which are peculiar, membrane-bound cell organelles which consist of ethereal terpenoids and aromatic oils suspended in carbohydrates- or protein-rich matrix, while the other two phyla do not. These oil bodies are very important biological markers for the taxonomy in the Marchantiophyta (Asakawa, 1982, 1995; Asakawa et al., 1979b, 2008c, 2012b, 2013a,b; Asakawa and Ludwiczuk, 2008a,b; Ludwiczuk and Asakawa, 2010).