eChapters

Abstract

In nature the roots of most of the plants are infected by fungi to form mycorrhizal associations, which play a central role in nutrient capture from the soil. These fungi are found in almost every terrestrial ecosystem; even in pioneer zones or very saline environments, and are reported to represent the second largest biomass component of many terrestrial ecosystems. Mycorrhizal associations are found in a broad range of habitats ranging from aquatic to deserts and alpine altitudes. In natural ecosystems mixed population of mycorrhizal fungi co-exist, with certain fungi becoming dominant in a particular patch and subsequently being replaced as environmental conditions change. Once this equilibrium is disturbed, the population dynamics is disrupted and a biomass may develop towards a few or even for one dominant fungus. Different species of mycorrhizae respond differently in response to the environmental conditions. In the present paper, all major types of mycorrhizal associations in different ecosystems are discussed.

Abstract

Different algal taxa involved in the formation of lichen/s are presented. To-date 43 algal genera, comprising members of Cyanophyta, Chlorophyta and one genus each of families Phaeophyceae (brown algae) and Xanthophyceae (yellow-green algae) are recorded, based on personal observations coupled with literature. The various algal taxa forming different lichens belonging to various families is presented. The taxa Trebouxia de Puymaly and Trentepohlia Born. amongst green algae; Scytonema Ag. and Nostoc Vauch. Among blue-green algae are dominant genera involved in the formation of lichens. The yellow and brown algae are only of rare occurrence.

Abstract

Soil is the natural growth media for living plants and microbes, and rhizosphere is niche for a group of soil microorganisms inhabiting around the plant root zone. The warmed and humid agro-climatic conditions of the area aggravate A. flavus contamination and aflatoxin production in maize grains from field to storage. In this article aflatoxin contamination in maize, antagonistic activity of rhizosphere microbes against toxigenic A. flavus, through fungi, antagonistic activity of rhizosphere bacteria against toxigenic A. flavus, bacterization of stored maize seeds for aflatoxin control and inhibition of aflatoxin production in stored maize seed with rhizobacteria has been discussed in detail.

Abstract

Many airborne fungal spores are important as allergens, human and plant pathogens, in the bio-deterioration of stored materials like paper, leather, textile, paintings, historical monuments and spoilage of food stuffs. Surveys have been conducted to elucidate the magnitude of the problem. Indoor environment also plays an important role in the precipitation of allergic symptoms caused by fungal spores. The present review briefly highlights some of the qualitative investigations carried out on indoor environments like bakery, building, cold storage, cow shed, dormitory, educational institutions, garbage disposal plant, ware house, hospital, library, food grain godown, leather godown, house dust, poultry house, chick hatcheries, plastic industries and textile industries.

Abstract

Microorganisms are potential tool for the production of large amount of potent and effective health care, food products and biofertilising agents. Recently, the marine microorganisms are considered as good sources of such products which may possess novel properties. There is a high scope for the exploration of marine microbes in order to search new product of economic importance from marine resources. Mangrove habitat is also part of marine habitat with the plant community having unique adaptation in their morpho- physiological and reproductive behavior. The high level of organic content in mangrove rhizosphre also leads to the colonization of degradative microorganisms and make them responsible for the creation of diverse and potential microbial community. Hence, mangroves are also considered as untapped resources of microbial metabolites and products. Several microorganisms including bacteria, fungi, algae, cyanobacteria, lichens are documented from mangrove habitats. These inhabitant microbes are the good source of secondary metabolites, therapeutic enzymes, food protective agents and mineral solubilisers. However, information on these aspects is very meager and thus the present review is an attempt to compile informations on the sources, properties and application of important microbes from mangrove ecosystems.

ABSTRACT

Microbes are integral part of the terrestrial ecosystem. Their function ranges from nutrients mineralization, stress alleviation to bioremediation in soils .There is a great possibility of using microbial inoculants as a biological tool for sustainable forestry and agriculture. This review gives an overview on the benefits of microbial technology and their contribution in development of green technology.

Keywords: Green technology, Microbes, AMF, PGPRs, Microbial consortium, Carbon sequestration.

ABSTRACT

Decomposition of litter is a dynamic process. It regulates cycling of nutrients in ecosystem. The productivity of an ecosystem depends on the turnover of carbon and other nutrients. Microbes play an important role in releasing of minerals locked up in organic complexes. The release of nutrients, however, is regulated by various climatic factors. The microbial succession at different stages of degradation of litter is controlled by the litter quality and species composition and biological activity. The present paper reviews the status of litter production, decomposition, species diversity and Biological activities as affected by the climatic and edaphic factors in tropical ecosystem.

Keywords : Litter decomposition, microbes, species diversity, biological activities, edaphic factors, tropical ecosystem.

Abstract

Trichoderma species play a vital role in the management of plant diseases in association with different commercial bioformutlations of the fungus. Its role as a successful pollution free environment and friendly mechanism of action has been highly exploited. The diversity of species based on location, type of agri-land and association with different fauna  and flora has been instrumental in large upsurge of biological methods of Plant disease management. Pollution of agri-land soils with chemicals, heavy metals and development of resistance to diseases has become an emerging problem coupled with the high costs of Infrastructure. Thus, the interest in alternative biologically based systems is the need for bioremediation, bioecology and biocontrol with Trichoderma.

Abstract

Nematodes are non-segmented worms typically 50 µm in diameter and 1 mm in length. Those few species responsible for plant diseases have received a lot of attention, but far less is known about the majority of the nematode community that plays beneficial roles in soil. Nematode diversity tends to be greatest in ecosystems with the least disturbance. Species of Aphelenchoides, Ditylenchus spp, Helicotylenchus, Meloidogyne spp., Pratylenchus, Scutellonema  and Rotylenchulus are obnoxious plant parasitic nematode beside Heterodera and Globodera. Soil temperature, soil structure, soil pH, soil moisture and soil texture play major role in movement of nematode, infestation and completion of life cycle under abiotic and biotic stresses.

Abstract

Elaboration of mycotoxins by several moulds in different agricultural commodities has been reported to be widespread. The mycotoxins are reported to cause variety of health hazards in different animals including Chicks, cow, horse, rat, Mouse, pig, rabbit, dog, including man. More than 150 species of moulds are reported to elaborate chemically and biologically diverse toxic metabolites. These mycotoxins  are known to induce variety of diseases commonly known as mycotoxicoses.The fungi which elaborate mycotoxins are diverse belonging to different groups of fungi.Mycotoxigenicity of these moulds not only differ among different genera but also among different species.  Some fungi such as Aspergillus flavus, A. terreus, Penicillium griseofulvum, P.expansum, P.nordicum, P.verrucosum, Fusarium acuminatum, F.culmorum, F. graminearum, F.moniliforme, F.oxysporum, F.solani, F. tricinctum and Cheatomium globosum are known to produce more  one  type of mycotoxin which differ in their chemical structure and biological activity.

ABSTRACT

The present paper describes application of synergistic action of microalgae viz., Spirulina platensis, Chlorella vulgaris, and Oscillatoria princeps coupled with state-of-the-art microbial biotechnology (that involved strains of Bacillus subtilis, Nitrobacter winogradskyi, Aspergillus flavus, and A. niger) developed by Biotechnology Resource Centre (BRC), Mumbai for treatment of secondary liquid effluents from a gelatine manufacturing industry. The growth of mixed cultures of selected microbial and algal species was measured respectively in terms of Colony Forming Units (CFUs) and Optical density (O.D.) of the culture. The results were indicative of efficient degradation potential of the proteinaceous liquid effluents. Moreover their BOD and COD loads reduced by 30.75 % and 84.10 % respectively after the treatment. Furthermore, the bio-safety of algal biomass cultured in selected effluents as feed supplement was tested on Swiss albino mice (Mus musculus). Mice in treated group didn’t exhibit any observable adverse effect on their growth or on their reproductive performance. In fine, the liquid effluents of gelatine manufacturing industries were polished along with production of probiotic food supplement.

ABSTRACT

Pesticide degradation is the breaking down of toxic pesticides into a non-toxic compounds and, in some cases, down to the original elements from which they were derived. The most common type of degradation is carried out in the soil by microorganisms, especially the fungi and bacteria. Microbial degradation depends not only on the presence of microbes with the appropriate degradative enzymes, but also on a wide range of environmental parameters. Pesticides which are rapidly degraded are called non-persistent while those which resist degradation are termed as recalcitrant (persistent). Microorganisms are able to degrade a large variety of compounds, including pesticides under laboratory conditions. However, methods have yet to be developed to decontaminate the environment from pesticide residues. Continuous efforts are required in this direction, and at present several PGPR capable of degrading pesticides have been isolated from the natural environment. Catabolic genes responsible for the degradation of several xenobiotics, including pesticides, have been identified, isolated, and cloned into various other organisms such as Streptomyces, algae, fungi, etc. In addition, recombinant DNA studies have made it possible to develop DNA probes that are being used to identify microbes from diverse environmental communities with a unique ability to degrade pesticides. Bioremediation treatment still requires more intense research through specific microbial degradation of broad range of organic pollutants. This review describes recent advances in biodegradation of pesticides by addressing the microbes involved in pesticide degradation.

Abstract

Mycorrhizal symbiosis is a highly evolved mutually beneficial relationship found between Arbuscular Mycorrhizal Fungi (AMF) and vascular plants. Knowledge of taxonomic and functional diversity of AM fungi is important in understanding the biology and ecology of such a widespread mycorrhizal symbiosis. Classification and identification of AM fungi remains in the formative stages of growth, with all the attendant turmoil. Since Glomus is known to be an important AM genera for providing multifacet benefit to several economically important plants. Hence, in this review article an attempt has been made to describe 120 Glomus species along with the line diagram of 63 Glomus species for their proper identification that can be used as an identification manual for mycorrhizal researchers.

ABSTRACT

Microorganisms play a key role for the proper running of the ecosystem. They help in nitrogen fixation, which is unique and most necessary property found only in this group. They help in decompositions, mineralization, nutrient cycling, phosphate solubilization, soil aggregate formation, symbioses, parasitism and many other important works. A great emphasis has been given by many scientists to conserve the microbial diversity. Developing human civilization has a great negative impact not only on the above ground biodiversity but also on the belowground biodiversity. This article is an overview, what important and crucial role nitrogen fixers play for maintaining soil and plant health. Nitrogen fixer not only fixes atmospheric nitrogen but also produces growth promoting hormones which are very important for plant growth. 

ABSTRACT

Biodiversity is often understood in terms of wide variety of plants, animals and micro-organisms existing on the earth. So far, about 1.75 million species have been identified, mostly small creatures such as insects. According to scientific estimates, there are actually about 13 million species, although range from 3 million to 100 millions. The present article deals with the importance and threats of biodiversity as well as tries to highlights the role of government and non-government sectors in conservation of biodiversity. The initial part of the article indicates the concept of evolution and biodiversity, wherein we have tried to identify the present scenario. We find that a wide range of microbial, plant and animal species are sources of various biological products for human use and welfare. These species are getting lost or extinct due to lack of conservation over a period of long time. Therefore, an effort has been made to highlight the conservation acts and important rules and regulations for protecting and conserving the bio-resources.

Abstract

Since the first oil well drilled successfully in 1859, crude oil has been a serious problem around world, including Indonesia. As a source of all petroleum products, crude oil is very complex component and divided into aliphatic, aromatic, resin and asphaltene. Petroleum products have been used for daily life and created large amounts of pollutants in environment and ecosystems around the globe. The pollutants should be treated by certain method; among them, bioremediation has several advantages to resolve the problem. In 2003, Ministry of Environmental (MoE) – Republic Indonesia was endorsed with a new regulation about biological treatment or bioremediation for crude oil contaminated soil (MoE regulation No. 128/2003). The most important to be noted in bioremediation process is the presence of microbes with certain metabolite capabilities. The degradation rate also can be improved and sustained by ensuring the adequate required factors. This article describes the removal of crude oil by utilization of microbial potentials, factors affecting biodegradation, and how they are applied in Indonesia.

Abstract

Sustainable landscape and forest management are of utmost concern in alleviating climate change. Fungal mutualism is one of the most significant positive biotic interactions responsible for forest structure and longevity. Coastal sand dunes imitate xeric habitats, while mangroves and river floodplains are often marshy. In spite of such extremities, mycorrhizal fungi are prominent component in coastal vegetation. Studies so far revealed that mycorrhizal association in herbaceous plant species is responsible for dune formation, stabilization and serve as potential inoculum in coastal habitats. Mycorrhizal association facilitates plant species to exploit larger volume of soil, supply nutrients (organic nitrogen, phosphorus and minerals), aggregates soil, provides tolerance to salinity stress, relieves from water stress and protects roots from pathogens. Human interference has severe impacts on plant-mycorrhizal mutualism in coastal habitats. Cultivation of exotic tree species and their uncontrolled exploitation further impoverish the habitats. Protection of native herbaceous flora, cultivation of native tree species and introduction of selected indigenous keystone species in disturbed habitats with mycorrhizal mutualism is an appropriate measure of rehabilitation.

Abstract

Alleviating plant salt stress and remediating saline soils are of great economic interest. Beneficial microbes such as arbuscular mycorrhizal (AM) fungi, plant growth promoting rhizobacteria (PGPR), etc. are associated with many plant species including trees. These beneficial microbes can cope up with salinity and help the plants to survive in such soils. Diversity status of beneficial microbes from the samples collected from different salt affected areas was investigated by many researchers. They screened and identified the efficient PGPR isolates isolated from saline areas for plant growth hormone (IAA) production and phosphate solubilization. The significance and highlights of the recent research as well as the past understanding of beneficial microbes and their role in reclamation of saline areas is discussed in this paper.

Abstract

Mine spoils pose adverse conditions for soil microbes and plant growth, due to its low organic content and other essential nutrients, unfavourable soil chemistry and poor soil texture. Poor microbial population inhibits nutrient transformation, consequently the establishment of the plants and ultimately affects the process of ecological succession. A synergy among different groups of beneficial microbes accompanied by plantation of suitable tree species on mined over area has proved to be effective for speedy and efficient revitalization of the mined affected lands. Inoculation of plantation with efficient strains of native microbes accelerates the soil redevelopment and helps to establish nutrients cycle readily which attracts native flora thereby the pace of natural regeneration is increased. It is therefore imperative to consider the application of effective microflora in restoration of mined lands along with the plantation.

Abstract
 
Opencast mining destroys the original land ecosystem and microbial community due to mining and stockpiling of mine rejects on adjoining land, which is a matter of great environmental concern. Mining creates formation of wastelands, formation of gullies, ravines, overburdens, reduced water infiltration and increased runoff. Reclamation of mined out areas is often difficult due to its chemical, physical and biological traits. Absence of topsoil is the most common feature of the mine spoils dumps. Arbuscular mycorrhizal fungi (AMF), the synonym of VAM fungi, are important microbes of soil that form symbiotic association with most of the terrestrial plants on the earth. Observations led to use of legume microsymbionts as biological substitutes for fertilizers. AMF diversity increases with species diversity of plants as the potential number of association increases. Dominant arbuscular mycorrhizal fungi can prevent the invasion of non-mycorrhizal plants on land where they have established symbiosis and promote their mycorrhizal host.