eChapters

Ralstonia solanacearum is a phytopathogenic bacterium belong ing to the b subdivision of the Proteobacteria (Yabuuchi et al., 1995) having a wide geographical distribution ranging from tropical, subtropical and warm temperate regions (Liu et al., 2009). It has broad host range and infects around 54 plant families and 450 plant species (Hayward, 1991; Wicker et al., 2007). 

Early attempts to study the diversity present in the R. solanacearum species complex resulted in separate race and biovar systems. R. solanacearum has been phenotypically classified into 5 races based on the host range at the plant species level and into five biovars based on the metabolic profiles related to the ability to reduce three disaccharides and three hexose alcohols (Wicker et al., 2007).

Microorganisms are diverse group of organisms differing in many ways and range from saprophytic to virulent one. Virulent are pathogenic and harmful to human and animals and can cause latent to per acute disease. Nowadays although treatment is available for most of the diseases, it is better to prevent the disease rather than going for treatment. Development of immunity is the aim of immunization and hence through knowledge of the host parasite interaction, epitope of the microorganisms responsible for the inducing protective immune responses is of pivotal importance.

Many microbes have ability to attach to various surfaces forming three dimensional extracellular matrix within which embedded the microbes grow and multiply forming thin layer structure called biofilm. Biofilms may form on living or non-living surfaces and can be prevalent in natural, industrial and hospital settings (Hall-Stoodley et al., 2004). Biofilm mainly consist of three components - bacteria, matrix and surface. Extracellular matrix generally composed of extracellular polymeric compounds such as extracellular polysaccharides, proteins, phospholipids, DNA, teichoic and nucleic acids, and other polymeric substances hydrated to 85 to 95% water and polysaccharides (Hall-Stoodley et al., 2004).

Production of Indole-3 Acetic acid (IAA) and mineral phosphate solubilization (MPS) are two predominant and direct mechanisms used by plant growth promoting rhizobacterial strains (PGPR). These traits are widespread among bacteria. Moreover, the role of IAA in plant-microbe interactions is diverse varying from pathogenesis to phytostimulation, to its role as a signaling molecule in microorganisms. With the advent of high performance analytics, molecular tools and recombinant methods, it has become feasible to investigate biochemical pathways of bacterial IAA synthesis at the genetic, biochemical and chemical levels. In the current study, we isolated several PGPRs from Western Ghats region, India.  Of all the efficient isolates, Serratia marcescens SM15 emerged as the most efficient PGPR isolate based on in vitro plant growth assays and ability to express PGPR traits.

Polyhydroxyalkanoates (PHAs) are diverse biopolyesters synthesized by many bacteria as carbon and energy reserved materials under unbalanced growth conditions. Sand-dunes have low nutrient contents especially nitrogen (N) and phosphorus (P) thus could harbor potential PHA accumulating bacteria. There is no report of isolation of PHA producing bacteria from the sand-dunes environment.  Sand samples of rhizosphere and non-rhizosphere regions of the coastal sand-dunes were processed on Nutrient Agar and TYG-Agar media for isolation of heterotrophic bacteria.

The diversity of the haloarchaea found within a crystallizer pond of a solar saltern located in Siridao and Ribandar, Goa, India was examined. Both cultured-based and culture independent methodology were employed which included  surface spreading of samples on different media containing 25% crude salt/NaCl, DNA extraction from sediment and water samples, amplification of 16S rRNA gene and DGGE.

Introduction

Mosquito-borne diseases such as malaria, filariasis, Japaneseencephalitis, chikungunya and dengue hemorrhagic fever cause extensive morbidity and take heavy toll of life in the developing nations particularly in the tropics. Every year about 300-500 million people are estimated to be affected by malaria alone (WHO report, 2000). In India around two million cases of malaria are being reported annually although real burden is many fold higher (Kumar et al. 2007). Similarly, lymphatic filariasis caused by Wuchereria bancrofti affects about 120 million people worldwide. India contributes about 40%  to  the total global burden of filariasis and accounts for about 50% of the people at risk of infection (ICMR bulletin, 2002). Anopheles stephensi is recognized as a major vector for urban malaria in India (Kumar 1997).

Introduction

Foraminifera or forams for short are the most abundant, diverse and widely distributed Protists in marine realm. They are found in all marine environments, from the inter-tidal to the deepest ocean trenches, and from the tropics to the poles (Todo et al., 2005). In some places, foraminifera are so abundant that the sediment on the bottom is mostly made up of their shells. For example, tourists from all over the world get attracted to the pink sands of Bermuda. These sands get their colour from the shells of Homotrema rubrum which has pink to red-colored shells. Living representatives of foraminifera provide ecological data and their mineralized tests are a geochemical record of palaeoclimatic conditions.

Introduction
 
Biodiversity a term to describe variability between organisms or populations of organisms, has different facets depending on the level of diversity considered (Species, population, ecosystem) or the organisms concerned (Barbault, 1992). Biodiversity can be exploited in many ways at scientific levels, the best known and the most ancient no doubt being in taxonomy and systematics, and more recently for studies of population biology, evolution and conservation of ecosystems, or for selection of materials for biotechnology.

The quest for drugs from the sea has yielded a remarkable di versity of natural products mostly from invertebrates such as sponges, tunicates, bryozoans etc. These molecules are either in late stages of clinical trials or have already entered the market. There has been an increased emphasis on marine microorganisms as sources of bioactive compounds over the past decade. Marine bacteria alone constitute 10% of the total living biomass carbon of the Earth’s biosphere and they have unique metabolic and physiological capabilities to ensure their survival in diverse habitats. In the marine environment, some microorganisms associate with living and non-living surfaces and the competition amongst these microbes for space and nutrients leads to the production of bioactive secondary metabolites.

The microbial community is a gold mine for gene(s) and pathway(s) that encode novel biocatalysts for biosynthetic or biodegradation processes, including degradation of pollutants, synthesis of biofuels and production of novel drugs. Sequencing of the microbial genome will also provide insights into the ecology of  microorganisms that are beneficial to, or threaten, crop production, and that ensure the quality and provision of ecosystem services. These unique genetic and biosynthetic capabilities of microorganisms have made them likely  candidates for solving particular difficult problems in the agriculture. For many years microbiologist and microbial  ecologists have tended to differentiate microorganisms as beneficial and harmful according to their function and how they affect soil quality, plant growth, and yield and plant health.

Duff and  Daly (2002) briefly describes the commonly found orchid diseases. These include the Bacterial soft rot caused by Erwinia carotovora, black leg or slow decline caused by Fusarium spp., petal blight caused by Curvularia eragrostidis [PseudocochlioBolus eragrostidis] and Alternaria alternata, top rot/shoot rot caused by Phytophthora parasitica, and stem rot caused by Sclerotium rolfsii [Athelia rolfsii].

India ranks 23^rd among world exporters of floriculture products and its share in the world exports are at around 0.38 per cent. It is estimated that fresh cut flowers of worth Rs. 100 crores are being exported annually from India. On the other hand the post harvest losses are estimated to be more than 30-35 per cent. The loss of quality in ornamentals may result from wilting or abscission of leaves and petals, yellowing of leaves and geotropic or phototropic bending of scapes and stems. Several factors prevailing during pre harvest, harvest and post-harvest stage affect the post harvest quality and longevity of cut flowers. Each step in the life span of post-harvest flower is associated with a number of coordinated biochemical, physiological, hormonal and structural changes that are strongly modulated by the fluctuations of environmental factors and stresses of biotic and abiotic origin.

Orchids are perennial ornamental crop, grows well in shady and humid places in wild habitat. The same growing conditions can be achieved by making special structures known as orchidaria or orchid houses.
Basics for Orchid House Cultivation
The following points should be considered during the construction of orchid houses:-
    ·    Topography of land.
    ·    Climate of region.
    ·    Type of soil and water.
    ·    Accessibility of area, transport and marketing facilities.
    ·    Proper drainage facilities.
    ·    Availability of good quality irrigation water.
    ·    A good infrastructure like availability of electricity.

Orchid Morphology

Most of the orchids are perennial herbs with simple leaves. Although the specialized flower structure confirms to a standard plan, the vegetative parts are shown great variation, a large number of them being epiphytes, or terrestrial and a few saprophytes are leafless in nature. Orchids can be divided into two groups - monopodial or sympodial depending upon their habit of growth. Monopodial orchids such as Vanda have a main stem which continues to grow year after. Sympodial orchids such as Cymbidium have a main stem, which terminates growth at the end of each season. A new shoot then grows from the base forming its own bulbous stem called pseudo-bulb, which eventually flowers. The pseudo-bulb or thickened stem is a very useful device for the storage of food and water and function like bulbs. In addition to the epiphytic orchids, there are also grounds orchids or terrestrial orchids, which grow like ordinary plants with their roots in soil. Most of the temperate zone orchids are terrestrial and tropical orchids are epiphytes.

Theophrastus gave the name “ORCHIDS” to the group of bizarre plants on the basis of the resemblance of paired underground tubers of these plants to masculine anatomy. This resemblance was also responsible for the mistaken belief that the orchids posses aphrodisiac properties and eating of underground tubers might “provoke venus” and they may be get male children. The appreciation of orchid beauty has a very long history in both the Western and Eastern cultures. Much of this is attributed to the diverse form and structure of orchids and the large number of species in the orchid family. Orchidaceae is amongst the most diverse family of the flowering plants consisting of 35,000 species under 880 genera (Kumar and Sheela, 2007, Fay and Chase, 2009). Orchids belong to the highest level of organization and are distinguished by the complicated biology of reproduction with long developmental cycle (Vakhrameeva et al., 1991, Sherif et al., 2012). They are beautiful and exotic perennial herbs grown in both north and south hemispheres. They exhibit an incredible range of diversity in size, shape and colour of flowers. Its flowers have lustrous, translucent petals rich in variegated colors and fragrances. Generally Orchids can grow at different elevations (Kumar and  Sheela, 2007).

Abstract
 
Nigeria has a very large domestic market, but consumers, farmers, processors and other agribusiness investors are often faced with challenges getting timely and relevant information. However, it has been found out that in Nigeria many people preferred receiving information over a mobile phone than a computer. The problems farmers encounter in exchanging information and that more than half of Nigeria’s population are mobile phone subscribers of which majority of them are farmers necessitate overview of Information and Communication Technologies (ICTs)  and agricultural development in Nigeria. Literatures were consulted, secondary data, and personal observations were tools used to compile the chapter contribution.

Abstract

With the evolution of Information and Communication Technology (ICT) in Agriculture as the major employer of Ugandans population with over 82% of the population, agricultural information is a key component in improving small-

Abstract

The contribution of agriculture to the Tanzania’s economic growth has not been fully realized due to the sector’s’poor performance. This is attributed to a combination of constraints, which are often aggravated by lack of access to timely, relevant and reliable agricultural information. The traditional approach of delivering agricultural information through extension services has been criticized widely as there are weak information flows amongst agricultural actors.

1. Introduction

For the last years, Peru’s GDP has been continuously growing, and in 2010 the agricultural sector has played a significant role in this process. According to the National System on Agricultural Innovation, the sector has an important contribution in economic and social aspects.Regarding the former, national agrarian production represents 8% of global GDP.
 
Statistics of the Ministry of Agriculture of Peru show that the agricultural sector includes 31% (3 million people approximately) of the country’s Economically Active Population (EAP), and 65% of the EAP in rural areas. The latest agrarian census indicates that almost 5.5 million hectares are used for agricultural activities, which accounts for 15% of the total surface.