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In 1985, Sir Alec Jeffreys developed restriction fragment length polymorphism (RFLP), which quickly became the standard technique for DNA testing throughout the 1980s. RFLP provided the world with the first form of genetic testing based on DNA, the body’s genetic material.

Definition : RFLP analysis is a difference in homologus DNA sequences that can be detected by the presence of fragments of different lengths after digestion of the samples in question with specific restriction endonucleases (RE).

A restriction fragment length polymorphism , or RFLP, (commonly pronounced “rif lip”), is a variation in the DNA sequence of a genome that can be detected by breaking the DNA into pieces with restriction enzymes and analyzing the size of the resulting fragments by gel electrophoresis. It is the sequence that makes DNA from different sources different, and RFLP analysis is a technique that can identify some differences in sequence (when they occur in a restriction site). Though DNA sequencing techniques can characterize DNA very thoroughly, RFLP analysis was developed first and was cheap enough to see wide application. Analysis of RFLP variation was an important tool in genome mapping, localization of genetic disease genes, determination of risk for a disease, genetic fingerprinting, and paternity testing.

Nine cyanobacterial strains viz., Anabaena variabilis, A. fertilissima, Nostoc muscorum, N. punctiforme, N. linckia, N. commune, Spirulina platensis, Westiellopsis prolifica and Hapalosiphon sp. were cultured in the laboratory. The growth curve for each culture was studied by growing them in Erlenmeyer flask using BG-11 growth medium. They were examined to determine the early stationary phases of their life-cycle, which are believed to be the most appropriate period for the production of secondary metabolites by an organism. After 23-25 days of incubation period, each culture was harvested and spent medium was collected by filtration of the biomass. Hexane, ethyl acetate, dichloromethane and methanol were used as the solvents for obtaining the extracts from biomass and spent medium of each culture which were then investigated against five pathogenic bacteria viz., Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Salmonella typhi. Antibacterial activity of different cyanobacterial sp. has been shown in various tables.

What are Retrotransposons?

The presence of mobile elements, capable of moving from one region of the genome to another, has been known and thoroughly studied since the 1950’s. These elements are capable of exciding and inserting themselves from one region of the chromatin to another, through their peculiar terminal repeat regions. This process is mediated by enzymes encoded by the transposon itself.

Retrotransposons are a class of mobile elements, widespread in plant genomes, where they account for a significant part of noncoding DNA. Barley, for example, contains thousands of copies of the Bare-1 element, dispersed throughout the euchromatic regions of chromosomes and exhibiting sequence identity higher than 95% to each other.

Unlike other classes of mobile elements, retrotransposons insert into the genome via an RNA intermediate, synthesized by their own reverse transcriptase, without the loss of the parental copy. Unique sequence properties show that retrotransposons of the Ty1-copia group are close to retroviruses, and their mode of integration in the host genome is also very similar.

The number and exact point of insertion of retrotransposons may differ from one individual to another and this can be exploited to characterize individuals, varieties or species, depending on how recent the transpositional event is. Furthermore, insertion of a retrotransposon is an irreversible event, a characteristic that can be helpful when tracing an ancestry.

Cyanobacteria have been identified as one of the most promising groups of organisms from which novel and biochemically active natural products are isolated. Cyanobacteria such as Microcystis, Anabaena, Nostoc and Oscillatoria produce a great variety of secondary metabolites. The only group comparable to cyanobacteria is actinomycetes, which has yielded a tremendous number of secondary metabolites. The rate of discovery from traditional microbial drug producer like actinomycetes, which is in the focus of pharmaceutical research for decades, is decreasing and it is the time to turn to cyanobacteria and exploit their potential. Recently, there has been an increasing interest in cyanobacteria as a potential source of new drugs (Glombitza and Koch, 1989; Schwartz et al., 1990). This is of paramount importance to fight increasingly resistant pathogens and newly emergent diseases (Hayashi et al., 1994).

Cyanobacteria are photosynthetic microorganisms that have flourished on earth for more than 3 billion years with some genera showing only minor morphological changes since that time (Hagmann and Juttner, 1996). The medicinal and nutrient qualities of cyanobacteria were first appreciated as early as 1500 BC, when Nostoc species were used to treat gout, fistula and several forms of cancer (Pietra, 1990; Bladon, 2002; Liu and Chen, 2003).

The excessive and imbalanced use of nitrogenous fertilizers in the last few decades to meet the challenges of growing food demand of Worlds population has led to serious consequences of soil and water pollution, leaching of toxic nitrate into ground water and volatilization of nitrogen oxides into the environment. Therefore, judicious management of nitrogen in the environment is very much essential in the development of more productive and sustainable agriculture. Rapid declining of non-renewable energy sources viz. petroleum products, natural gas as well as energy crisis in the recent days, release of several pollutants during production of fertilizer N has also necessitated the development of alternative and/or supplemental technologies to obtain the fertilizer N for crop production.

Abstract

The rhizomicrobiome plays a vital role in maintaining plant health and is highly influenced by the root exudates of the host plant. Plants select a subset of microbes at different stages of their development, and determine the microbiome community composition in its immediate vicinity presumably for specific functions. The rhizomicrobiome is composed of diversified microbial community with specific functions and is highly influenced by the plant type, soil type and environmental conditions. The rhizomicrobiome communities apart from promoting plant growth also elicit induced systemic tolerance to salinity and drought in stressed plants. Bacterial communities producing 1-aminocyclopropane-1-carboxylate (ACC) deaminase modulate stress ethylene in plants and alleviate the effects of abiotic stress and increases plant adaptability to stressed environment.

Rhizosphere

The term Rhizosphere was introduced by the German scientist, Hiltner in 1904. It is region of the soil, which is subjected to the influence of plant roots. It is the unique environment under the influence of plant roots. The roots of plants are not only involved in the uptake of mineral nutrients and water for plant growth, but they also release a wide range of organic compounds in the surrounding soil.

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.

To a soil microorganism, the rhizosphere is like a lush oasis in the desert. In comparison to near-starvation conditions of the bulk soil, the rhizosphere is the place where nutrients are plentiful and microorganisms flourish. The term rhizosphere was first used by Hiltner in 1904 to describe the zone of soil under the influence of roots. The rhizosphere can extend more than 5 mm from the root and is the area of increased microbial activity due to exudation of low molecular weight compounds from root cells. The rhizoplane is the surface of plant root and any strongly adhering soil particles. The microbial populations that colonize the interior of the root and from intimate associations with the root are considered endophytes.

11.1 Principles and Framework for Risk Assessment
11.1.1 Introduction
Risk assessment is an indispensable scientific tool in evaluating the safety and potential impacts of genetically modified (GM) crops on human health, animal welfare, and the environment. It provides a structured, evidence-based framework for identifying hazards, characterizing risks, and proposing mitigation strategies before the approval and commercialization of GMOs. In the context of biotechnology and regulatory biosafety, risk assessment ensures that GM crops meet both national and international standards for biosafety and sustainability.
11.1.2 Definition of Risk Assessment
Risk assessment is defined as the systematic process of identifying, evaluating, and characterizing the potential adverse effects arising from exposure to a GMO or its products, under specified conditions of use.
Risk = Hazard × Exposure
Where hazard is the potential to cause harm, and exposure is the likelihood of encountering the hazard.
11.1.3 Objectives of Risk Assessment in GM Crops
• To evaluate the safety of GM crops for human and animal consumption.
• To assess the potential environmental impacts, including effects on biodiversity, gene flow, and ecosystem interactions.
• To ensure that regulatory decisions are science-based, transparent, and precautionary.

Abstract

Anaerobes are a diverse groups of microorganisms which do not require oxygen or energy for respiration/metabolism and are one of the important components of nitrogen cycle. They are capable of using various other organic and even inorganic materials as electron acceptors during respiration. Anaerobic based wastewater treatment is a biological approach where microorganisms degrade organic contaminants (i.e. rich in carbon and nitrogen) in the absence of oxygen. In this chapter, the role of anaerobes in wastewater treatment has been discussed as it offers an alternative, cheap and eco friendly treatment technology among different biological treatment methods. Anaerobic biological treatment of wastewater is well developed, understood, and frequently used in anaerobic digesters to treat complex organic carbon and nitrogen compounds such as primary and secondary wastewater sludge. The anaerobic sludge contains diverse groups of anaerobic microorganisms that work together in association via a multistage processe consisting of the following biochemical reactions like hydrolysis, acidification, acetogenesis, and methanogenesis thereby converting the organic matter to biogas. The composition of biogas includes 70% methane (CH₄) and 30% carbon dioxide (CO₂) in addition to traces of other gases (e.g., H₂ and H₂S). The methane produced as a by-product can be used as an energy source. The potentiality of anaerobes in anaerobic based bioreactors for its maximum efficiency can be implemented in a variety of ways. The chapter discusses about the working principle, performance, treatment potential, and cost implication in the application of anaerobic treatment technology. The main bioprocess parameters such as pH, temperature, mixing, organic loading rate (OLR), and hydraulic retention time (HRT) have also been discussed in brief. Anaerobic treatment offers several benefits over aerobic treatment, including lower energy requirements, less chemicals, low capital, operation, and maintenance costs, and less sludge production. Hence, it saves money and the environment and overall simplifies the whole process.

Abstract

Of the various rhizosphere associated bacteria, Azospirillum species are probably the most studied and appear to have significant potential for commercial application. During the last 35 years of studies of Azospirillum–plant interaction, over 20 proposals were suggested for the mechanism of action by which Azospirillum  enhances plant growth, yield and nutrient uptake. Besides, fixing the nitrogen with associative symbiosis, they impart a number of beneficial effects on plants such as phytohormone production, siderophore production, enzyme production, proliferation of root system, enhanced water and mineral uptake, mobilization of minerals, mitigation of environmental stressors of plants, and moderate biocontrol potential. The following plant responses to Azospirillum inoculation in agriculture crops were often reported: increase the germination percentage and height of the seedlings, increase the total number and length of adventitious roots and root hairs, increase the hydraulic conductivity of the root system, increase in the height of the shoot and dry matter production and yield of the crop plants. The effect of Azospirillum inoculation on the total yield increases of field grown plants generally ranged from 10 to 30 per cent. This article reviews the recent researches on role of Azospirillum in plant growth promotion.

ABSTRACT

Plasmids are circular, double-stranded DNA molecules which replicate autonomously from the chromosome of the host organism. Plasmids are found in many bacterial species and often confer upon the host cell phenotypic characteristics such as resistance to antibiotics, resistance to heavy metals, ability to produce particular protiens, conjugative (mating) ability and ability to degrade xenobiotc compounds. One of these degradative plasmids may encode a complete catabolic pathway (such as toluene to pyruvate, formate and acetaldehyde) or partial degradative steps, such as octane to octanol. In this later case, the remainder of the pathway may be encoded by chromosomal genes, by genes of other plasmid present in the host, or by other microorganisms. Many degradative plasmids possess a broad host range, especially among the gram-negative bacterial species.

There are different mechanisms which may be involved in the evolution of aromatic pathways in general and in the process of adaptation of microorganisms to xenobiotic substrates in particular. Gene transfer, the occurrence of plasmids in bacteria in the natural environment is an important pool of genetic information residing on plasmid vehicles may flow among indigenous microorganisms. Since many examples of self-transmissible plasmids that carry genes for degradation of aromatic or other xenobiotic compounds are known, and their role in spreading these genes to other microorganisms is well characterized. Early, studies of TOL, NAH, and SAL plasmids revealed strong homologies among these plasmids in regions both inside and outside the catabolic gene clusters. Plasmids, pJP4, pAC25, and PSS50, catabolic plasmids carrying genes for chloroaromatic degradation, have strongly homologous plasmid backbone that determine replication and transfer function. Furthermore, the chlorobenzoate plasmid p51 was also shown to be homologous to pJP4 outside regions of the catabolic genes. These observations suggest that a few common self-transmissible ancestor replicons (includes origin of replication and replication gene) may have been involved in acquisition and spread of different catabolic genes. DNA

Abstract

Agriculture is one of the most important factors contributing to the economic growth of India. Out of the 329 million hectares of India’s geographical area, about 114 million hectares are under cultivation. There are 17 essential elements required for proper plant growth. Of the mineral elements, the primary macronutrients (nitrogen, phosphorous, and potassium) are needed in the greatest quantities and are most likely to be in short supply in agricultural soils. Secondary macronutrients are needed in smaller quantities, and are typically found in sufficient quantities in agricultural soil, and therefore do not often limit crop growth. Micronutrients, or trace nutrients, are needed in very small amounts and can be toxic to plants in excess. Silicon (Si) and sodium (Na) are sometimes considered essential plant nutrients, due to their ubiquitous presence in soils.

The economy of India thrives on agriculture, the most practiced occupation in the country. Agricultural fertilizers are essential to enhance proper growth of plants and crop yield. Recently, farmers have been using chemical fertilizers for quicker and better yield. But these fertilizers endanger ecosystems, soil, plants, human and animal lives. In contrast, naturally grown biofertilizers not only give a better yield, but are also harmless to humans. This chapter aims to study the biofertilizers play a key role for enhancing economic development of sustainable agriculture (EDSA) in comparison to chemical fertilizers. Biofertilizers improve the crop yields, plant resistance, soil health, profit to farmers, and the benefit to cost ratio of biofertilizers were higher than chemical fertilizer, proved that the biofertilizers would lead to better sustainable economic development for the farmers and their country.

Role of Bioinputs explains how biological inputs contribute to soil health, plant performance, ecological interactions, and long-term agricultural sustainability. It introduces the conceptual framework and classification of bioinputs before examining their effects on soil microbial populations, enzyme activities, organic carbon, nutrient availability, soil structure, rhizosphere activity, and soil-fertility indicators. The chapter further explores plant–microbe interactions and plant–faunal relationships involving earthworms, beneficial nematodes, arthropods, microarthropods, protozoa, and the soil food web. By linking biological processes with physiological and agronomic outcomes, the chapter presents bioinputs as important components of resilient, ecologically balanced, and sustainable farming systems. across sustainable and natural farming systems.

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.

1. Introduction
The world’s ecosystem is facing significant challenges because of risingpopulations, more urbanization, and industrialization (Juwarkar et al.,2014). Significant environmental contamination has been caused by moderncivilizations, industrialization, population increase, intensive agriculturalpractices, human activities, and technological advancement (Lalevic et al.,2016).

Nano-bioinoculants are revolutionizing modern agriculture, empowering farmers with an innovative and environment-friendly approach to crop cultivation. This chapter delves into the fascinating world of these tiny technological breakthroughs that work seamlessly with nature to significantly enhance crop yields in a sustainable manner. Their remarkable ability to deliver essential nutrients directly to plants, fortify crops against drought and diseases, and minimize the reliance on harmful chemicals will be highlighted. By presenting real-world success stories, we will illustrate how farmers are harnessing these advancements to produce healthier food while conserving valuable resources. Nevertheless, the path to widespread adoption is not without its challenges; which will be confronted for critical issues such as costs, regulatory hurdles, and the transition of these solutions from laboratories to agricultural fields. Looking ahead, we will envision a future where nano-bioinoculants synergize with other cutting-edge farming technologies, paving the way for truly sustainable food systems that can meet the demands of our growing population.

1. Introduction
Oil spills are defined as the unintentional release of liquid petroleum hydrocarbons into the environment, predominantly impacting marine ecosystems. This form of pollution, often caused by human activities, can also occur onterrestrial landscapes. Spills typically result from the discharge of crude oilfrom sources such as tankers, offshore platforms, drilling rigs, and wells, aswell as from refined petroleum products like gasoline and diesel (Smith etal., 2019). While such incidents are primarily accidental, they may arise fromvarious circumstances, including inadequate storage or poor maintenance,leading tocontainerleaks. Historically, one of the earliest documented oil spillsoccurred in 1907 in Batum, a region then part of the Russian Empire (moderndayBatumi, Georgia). This incident, involving a collision between an oil-ladenship and another vessel in the Black Sea, marked the beginning of recorded oilspill events, though historical records from that time remain limited (Johnsonet al., 2021). The consequences of oil spills are profound, affecting both theenvironment and the economy. On the ocean’s surface, oil disrupts aquaticecosystems by blocking sunlight penetration and depleting dissolved oxygenlevels, which are vital for marine life. Crude oil compromises the insulating andwaterproofing properties of fur and feathers, leading to hypothermia and deathin oil-coated birds and marine mammals. Additionally, ingesting oil can causeseveretoxicity, while damage to habitats and reproductive systems often delaysthe long-term recovery of affected species. Coastal vegetation, particularly inecosystems such as saltwater marshes and mangroves, is also highly vulnerable