This document discusses the identification and classification of plant viruses that can be transmitted through seeds. It provides background on how inadequate identification early on led to confusion, but the establishment of standardized criteria and rules by the ICTV has helped create order. Over 200 virus diseases are known to be seed-transmitted. The document lists the taxonomic positions of many seed-transmitted viruses and viroids according to the latest ICTV classification, organized by order, family, and genus. It also discusses the identification process for seed-transmitted viruses and how classification assessments are made.
This document discusses principles of disease control in agricultural microbiology. It outlines four main principles: 1) Avoidance/Exclusion to prevent import and spread of pathogens, 2) Eradiation to reduce pathogen amounts, 3) Protection to directly protect plants from infection, and 4) Resistant varieties that hinder pathogen development. Specific control methods are described under each principle, including quarantine, sanitation, crop rotation, biological and chemical controls, and genetic engineering to develop resistant varieties.
This document discusses the classification of phytoplasmas, which are wall-less bacteria that infect plants and are transmitted by insect vectors. It begins by describing early observations of phytoplasmas and their causal role in plant diseases. It then discusses various classification systems used over time, beginning with symptom-based classification and moving to methods based on serology, DNA hybridization, RFLP analysis of 16S rDNA, and sequencing of 16S rDNA and ribosomal protein genes. The latest classification system divides phytoplasmas into 18 major 16Sr groups and over 40 subgroups, providing an overview of the molecular tools that enabled increasingly precise classification of these obligate plant pathogens.
- Phytoalexins are antimicrobial compounds produced by plants after exposure to microorganisms or abiotic stress. They are chemically diverse and fall into classes like terpenoids and alkaloids.
- The concept of phytoalexins was formalized in 1941 after observing that bean tissue produced inhibitory compounds when exposed to a fungal pathogen. Phytoalexins restrict pathogen growth at infection sites.
- Induction of phytoalexins involves MAP kinase signaling cascades and transcription factors like WRKY33 regulating genes in biosynthesis pathways. Camalexin production in Arabidopsis in response to pathogens depends on WRKY33 phosphorylation by MPK3/MPK6.
Epidemiology, etiology and management of fusarium wilt of muskmelonNageshb11
This document summarizes research on Fusarium wilt of muskmelon caused by the fungus Fusarium oxysporum f. sp. melonis. It provides background on the epidemiology, etiology, and management of the disease. It also presents 4 case studies that examined the influence of environmental factors on disease development, evaluated biological control agents for managing the disease, and assessed integrated management approaches. The case studies found that temperature, soil moisture, and texture influence disease incidence and that the bacteria Streptomyces olivaceus and fungi Trichoderma viride and Aspergillus niger show potential for biological control of the pathogen.
The concept of gene for gene hypothesis was first developed by Flor in 1956 based on his studies of host pathogen interaction in flax, for rust caused by Melampsora lini. The gene for gene hypothesis states that for each gene controlling resistance in the host, there is corresponding gene controlling pathogenicity in the pathogen. The resistance of host is governed by dominant genes and virulence of pathogen by recessive genes. The genotype of host and pathogen determine the disease reaction. When genes in host and pathogen match for all loci, then only the host will show susceptible reaction. If some gene loci remain unmatched, the host will show resistant reaction. Now gene – for –gene relationship has been reported in several other crops like potato, sorghum, wheat, etc. The gene for gene hypothesis is also known as “Flor Hypothesis.”
Procedures in the diagnosis of plants diseasesAmmad Ahmad
This document provides an overview of basic procedures for diagnosing plant diseases. It discusses the main types of plant diseases which are infectious diseases caused by pathogens and non-infectious diseases caused by environmental factors. For infectious diseases, it describes the signs and symptoms of diseases caused by fungi, bacteria, parasitic plants, nematodes, viruses, and mollicutes. It also discusses procedures for identifying the causal pathogens and key signs and symptoms.
This document discusses types of plant disease epidemics. It defines an epidemic as a disease occurring year after year at a moderate to severe level or an increase in disease within a population. Epidemiology is the study of disease in populations. The main types of epidemics discussed are monocyclic, polycyclic, and polyetic. Monocyclic diseases have one infection cycle per season, while polycyclic diseases can have multiple cycles from secondary infections. Polyetic diseases take multiple years to produce inoculum and may not cause new infections every year. Examples of each type are provided.
This document discusses principles of disease control in agricultural microbiology. It outlines four main principles: 1) Avoidance/Exclusion to prevent import and spread of pathogens, 2) Eradiation to reduce pathogen amounts, 3) Protection to directly protect plants from infection, and 4) Resistant varieties that hinder pathogen development. Specific control methods are described under each principle, including quarantine, sanitation, crop rotation, biological and chemical controls, and genetic engineering to develop resistant varieties.
This document discusses the classification of phytoplasmas, which are wall-less bacteria that infect plants and are transmitted by insect vectors. It begins by describing early observations of phytoplasmas and their causal role in plant diseases. It then discusses various classification systems used over time, beginning with symptom-based classification and moving to methods based on serology, DNA hybridization, RFLP analysis of 16S rDNA, and sequencing of 16S rDNA and ribosomal protein genes. The latest classification system divides phytoplasmas into 18 major 16Sr groups and over 40 subgroups, providing an overview of the molecular tools that enabled increasingly precise classification of these obligate plant pathogens.
- Phytoalexins are antimicrobial compounds produced by plants after exposure to microorganisms or abiotic stress. They are chemically diverse and fall into classes like terpenoids and alkaloids.
- The concept of phytoalexins was formalized in 1941 after observing that bean tissue produced inhibitory compounds when exposed to a fungal pathogen. Phytoalexins restrict pathogen growth at infection sites.
- Induction of phytoalexins involves MAP kinase signaling cascades and transcription factors like WRKY33 regulating genes in biosynthesis pathways. Camalexin production in Arabidopsis in response to pathogens depends on WRKY33 phosphorylation by MPK3/MPK6.
Epidemiology, etiology and management of fusarium wilt of muskmelonNageshb11
This document summarizes research on Fusarium wilt of muskmelon caused by the fungus Fusarium oxysporum f. sp. melonis. It provides background on the epidemiology, etiology, and management of the disease. It also presents 4 case studies that examined the influence of environmental factors on disease development, evaluated biological control agents for managing the disease, and assessed integrated management approaches. The case studies found that temperature, soil moisture, and texture influence disease incidence and that the bacteria Streptomyces olivaceus and fungi Trichoderma viride and Aspergillus niger show potential for biological control of the pathogen.
The concept of gene for gene hypothesis was first developed by Flor in 1956 based on his studies of host pathogen interaction in flax, for rust caused by Melampsora lini. The gene for gene hypothesis states that for each gene controlling resistance in the host, there is corresponding gene controlling pathogenicity in the pathogen. The resistance of host is governed by dominant genes and virulence of pathogen by recessive genes. The genotype of host and pathogen determine the disease reaction. When genes in host and pathogen match for all loci, then only the host will show susceptible reaction. If some gene loci remain unmatched, the host will show resistant reaction. Now gene – for –gene relationship has been reported in several other crops like potato, sorghum, wheat, etc. The gene for gene hypothesis is also known as “Flor Hypothesis.”
Procedures in the diagnosis of plants diseasesAmmad Ahmad
This document provides an overview of basic procedures for diagnosing plant diseases. It discusses the main types of plant diseases which are infectious diseases caused by pathogens and non-infectious diseases caused by environmental factors. For infectious diseases, it describes the signs and symptoms of diseases caused by fungi, bacteria, parasitic plants, nematodes, viruses, and mollicutes. It also discusses procedures for identifying the causal pathogens and key signs and symptoms.
This document discusses types of plant disease epidemics. It defines an epidemic as a disease occurring year after year at a moderate to severe level or an increase in disease within a population. Epidemiology is the study of disease in populations. The main types of epidemics discussed are monocyclic, polycyclic, and polyetic. Monocyclic diseases have one infection cycle per season, while polycyclic diseases can have multiple cycles from secondary infections. Polyetic diseases take multiple years to produce inoculum and may not cause new infections every year. Examples of each type are provided.
This document discusses breeding for resistance to biotic stresses in plants. It defines biotic stress as damage caused by living organisms such as pathogens. Major causes of agricultural loss are discussed, including different types of pathogens and their characteristics. Methods for developing disease resistance in plants are then outlined, including hybridization, selection from germplasm and related species, mutation breeding, and biotechnological methods. Specific examples of varieties developed for resistance to important diseases in crops like rice, wheat, sugarcane, and cotton are also provided.
Endophytic microbes live within plant tissues without causing harm and can benefit plants through various mechanisms. This document discusses endophytic bacteria and fungi, their transmission within plants, and how they can promote plant growth, act as biocontrol agents, and increase stress tolerance in plants. Specifically, endophytes produce plant hormones, fix nitrogen, make nutrients more available, and induce systemic resistance to pathogens or tolerance to stresses like drought. Their interactions with plants demonstrate potential for agriculture and phytoremediation.
The document discusses the role of enzymes, toxins, and growth regulators in plant pathology and disease development. It defines plant pathology and describes how diseases develop through a complex process influenced by environmental factors and stress. The summary is:
1) Plant pathology studies plant diseases and their causes and controls. Disease develops through interactions between pathogens, hosts, and the environment.
2) Key stages of disease development include inoculation, penetration, infection, pathogen growth and reproduction, and dissemination. Disease occurs when conditions are suitable for the pathogen but not the host.
3) Factors like temperature, moisture, light, soil properties, and wind influence disease development by affecting the pathogen, host, or their interaction. Understanding
In a computer simulation of an epidemic, the computer is given data describing the various sub components of the epidemic and control practices at specific points in time (such as at weekly intervals).Computer simulation of epidemics is extremely useful as an educational exercise for students of plant pathology and also for farmers so that they can better understand and appreciate the effect of each epidemic sub component on the final size of their crop loss.Simulators serve as tools that can evaluate the importance of the size of each epidemic sub component at a particular point in time of the epidemic by projecting its effect on the final crop loss.Computer simulation are expert systems,that try to equal and suppress the logic and ability of an expert professional in solving problems.Systems are used in plant pathology frequently for diagnosis of plant diseases.Systems can advice growers in making decisions on disease management in respect of kind, amount and time of application of pesticides etc.Simulators can decompose disease progress so they are used now to develop forecaster.
This document summarizes plant disease management through plant quarantine. It defines plant quarantine as legal restrictions on agricultural commodity movement to prevent the establishment of plants, pests, and diseases in new areas. It provides details on the history and organization of plant quarantine in India, including relevant laws and quarantine stations at airports, seaports, and land frontiers. The document lists some examples of diseases controlled by plant quarantine in India and introduces some foreign diseases introduced to India with the year and originating country.
Yellow vein mosaic virus is a devastating disease of okra (Abelmoschus esculentus) in India. It was first reported in India in 1924 and causes up to 80% crop loss if plants are infected early. The causal agent is a begomovirus transmitted by the whitefly Bemisia tabaci. Infected plants show a yellow vein pattern and stunting, and fruits are small and deformed. Management strategies include removing infected plants, controlling weed hosts, crop rotation, resistant varieties, and insecticide sprays.
The document discusses a study on the effect of different carbon sources on the production of hydrolytic enzymes in Trichoderma sp strains T13 and T14 and their ability to act as mycoparasites. Key findings include:
- Chitin was found to induce maximum production of chitinase, protease and beta-glucanase enzymes.
- T. reesei was able to produce hydrolytic enzymes like chitinase, protease and beta-glucanase when grown in soil in the presence of various fungal pathogens like Fusarium moniliforme, Fusarium solani, Rhizoctonia solani, Sclerotium rolfsii
Biological control is the suppression of one organism by another. There are two modes of mechanisms namely direct and indirect. Here I focused on the direct mechanisms such as parasitism, predatism, antibiotic-mediated suppression, lytic enzymes and unregulated-waste products. with the help of these various direct mechanisms, the bio-control agents will compete the pathogen's activity.
Different techniques for detection of plant pathogens.Zohaib Hassan
Plant pathology is the study of plant diseases. Major plant pathogens include fungi, bacteria, nematodes, and viruses. Techniques used to detect pathogens include histopathological examination of infected tissues, culture growth on media, staining, microscopy, and analysis of biochemical properties. Symptoms caused by pathogens can provide clues to identification. Isolation and purification of the pathogen allows for reinoculation to fulfill Koch's postulates.
This document discusses various methods for controlling plant diseases. The major methods discussed are cultural control methods, biological control methods, and chemical control methods. Cultural control methods include avoiding contact between the pathogen and host plant through proper field selection, resistant varieties, and modifying cultural practices. Biological control uses other organisms like fungi, bacteria, and mycorrhizal fungi to control pathogens. Chemical control involves the use of fungicides, bactericides, and other chemical treatments to directly kill or inhibit pathogens.
This document summarizes induced plant resistance against pathogens. It discusses the historical background of induced resistance being first observed over 100 years ago. It describes different types of induced resistance including systemic acquired resistance (SAR) and induced systemic resistance (ISR). SAR is mediated by salicylic acid and involves pathogenesis-related proteins, while ISR is mediated by jasmonic acid and ethylene. Biological agents like PGPR bacteria and plant extracts can also induce resistance. Signal transduction pathways underlying these responses are triggered upon pathogen recognition. While induced resistance offers opportunities for crop protection, practical applications are currently limited to some plants.
This ppt illustrates and describes the two bacterial diseases included in the BSc Hons Program Syllabys Core Course III or DSC 3- Citrus canker and angular leaf spot of cotton
Principles of plant disease managementRanjan Kumar
This document discusses principles of plant disease management. It explains that a plant disease is caused by the impairment of a plant's normal physiological functioning due to irritation from pathogens. Disease management aims to prevent disease incidence, reduce pathogen inoculum, and minimize crop losses. It does this by eliminating interactions between susceptible hosts, virulent pathogens, and suitable environments. The key principles of disease management are avoidance, exclusion, eradication, protection, use of resistant varieties, and therapy. Each principle is described in detail with examples.
This document summarizes the key principles of plant infection:
1) Penetration is the entry of the pathogen into the host, which can occur directly through the plant surface, through wounds, or through natural openings like stomata, hydathodes, or lenticels.
2) Infection is the establishment of the pathogen within the host plant by procuring nutrients from host cells or tissues.
3) Invasion is the spread of the pathogen within the host, which can be intercellular or intracellular depending on the type of pathogen.
4) Dissemination refers to the spread of the pathogen from one plant to another, which can occur autonomously through soil, seeds, or plant parts,
Development of transgenic plants for abiotic stress resistancetara singh rawat
The document discusses various genes that have been used to engineer abiotic stress tolerance in plants. It describes genes involved in synthesizing osmoprotectants like glycinebetaine and trehalose, antioxidant genes like superoxide dismutase, transcription factor genes like DREB1A, early response genes like ERD15, and genes that maintain membrane integrity and ion homeostasis. Engineering these stress-responsive genes into crop plants through genetic engineering approaches can help improve abiotic stress tolerance and food security.
SURVIVAL AND DISPERSAL OF PHYTOPATHOGENIC BACTERIA.pdfOm Prakash
SURVIVAL OF PHYTOPATHOGENIC BACTERIA
Phytopathogenic bacteria have the ability to survive both for longer & shorter periods including soil, seed, diseased crop debris, weed host, and insect vectors.
DISPERSAL OF PLANT PATHOGENIC BACTERIA
To make a healthy plant diseased, the first requirement of a pathogen is to spread its inoculum (primary as well as secondary) from the source of survival to the susceptible parts of a healthy plant. The spread of a plant pathogen within the general area in which it is already established is called “dispersal” or “dissemination”.
Moving the inoculum only a few inches and transporting it for hundreds of miles both constitute its dispersal or dissemination. However, pathogen dispersal is not necessary only for the spread of diseases but also for the continuity of the life-cycle and evolution of the pathogen. Detailed knowledge of pathogen-dispersal is essential to find out effective control measures for diseases because the possibilities of preventing dispersal and thereby breaking the infection chain always exist.
This document describes three types of symptoms caused by a bacterial disease in plants: 1) Seedling blight causes water-soaked spots on cotyledons that collapse and die. 2) Blackarm causes dark brown to black lesions on stems, petioles, and fruiting branches that crack and are easily broken. 3) Angular leaf spot causes small, dark-green spots on leaves that become angular, brown, and blackish as they enlarge and appear on both sides of the leaf. The bacterium can survive for years in soil and seed and spreads primarily through seed and secondarily through water, wind, and insects. Resistant varieties should be grown to manage the disease.
Importance of epidemics in mono and poly cyclic diseases caused by various plant pathogens and the mathematical models for studying the strategy of those epidemics
In this PPT you will come to know about the different types of mosaic virus which is caused in BHENDU crop, its life cycle, epidemiology, and its management.
The document discusses plant disease epidemics and epidemiology. It defines an epidemic as a disease that spreads rapidly to many individuals within an area over a short time period. Epidemiology is the study of epidemics and the factors that influence them, including the interaction between hosts, pathogens, environments, and human activities. For an epidemic to occur, there needs to be a susceptible host, a virulent pathogen, and favorable environmental conditions over an extended period of time. The interaction of these components can be visualized using a disease triangle or tetrahedron model. Examples of historical epidemics that caused famines are discussed.
The document discusses seed treatment methods for controlling seedborne diseases. It finds that treating rice seeds with manual cleaning and a 15% brine solution significantly reduced rice seedborne diseases like brown spot and bacterial leaf blight. This improved yields by 12-15% and seed quality, with fewer unfilled grains and discolored seeds. Another study evaluated treatments for controlling safflower seed and soilborne diseases. It found that treating seeds with the fungus Trichoderma harzianum greatly reduced disease incidence and severity of pathogens like Fusarium, yielding the highest seed production. A third abstract discusses using non-thermal plasma as a novel seed treatment method, finding it a potential alternative to conventional hot water, chlorine or fungicide
1. Subcutaneous mycoses are chronic fungal or bacterial infections of the subcutaneous tissues that can spread through the lymphatics or form sinus tracts. They are caused by organisms found in soil and are most common in tropical regions.
2. Mycetoma, also known as Madura foot, is a common subcutaneous mycosis characterized by a slowly progressive granulomatous infection of the skin and subcutaneous tissues of the extremities. It is caused by fungi like Madurella mycetomatis or bacteria like Actinomyces.
3. Diagnosis involves identification of fungal or bacterial grains from infected lesions through microscopic examination of potassium hydroxide mounts, staining techniques,
This document discusses breeding for resistance to biotic stresses in plants. It defines biotic stress as damage caused by living organisms such as pathogens. Major causes of agricultural loss are discussed, including different types of pathogens and their characteristics. Methods for developing disease resistance in plants are then outlined, including hybridization, selection from germplasm and related species, mutation breeding, and biotechnological methods. Specific examples of varieties developed for resistance to important diseases in crops like rice, wheat, sugarcane, and cotton are also provided.
Endophytic microbes live within plant tissues without causing harm and can benefit plants through various mechanisms. This document discusses endophytic bacteria and fungi, their transmission within plants, and how they can promote plant growth, act as biocontrol agents, and increase stress tolerance in plants. Specifically, endophytes produce plant hormones, fix nitrogen, make nutrients more available, and induce systemic resistance to pathogens or tolerance to stresses like drought. Their interactions with plants demonstrate potential for agriculture and phytoremediation.
The document discusses the role of enzymes, toxins, and growth regulators in plant pathology and disease development. It defines plant pathology and describes how diseases develop through a complex process influenced by environmental factors and stress. The summary is:
1) Plant pathology studies plant diseases and their causes and controls. Disease develops through interactions between pathogens, hosts, and the environment.
2) Key stages of disease development include inoculation, penetration, infection, pathogen growth and reproduction, and dissemination. Disease occurs when conditions are suitable for the pathogen but not the host.
3) Factors like temperature, moisture, light, soil properties, and wind influence disease development by affecting the pathogen, host, or their interaction. Understanding
In a computer simulation of an epidemic, the computer is given data describing the various sub components of the epidemic and control practices at specific points in time (such as at weekly intervals).Computer simulation of epidemics is extremely useful as an educational exercise for students of plant pathology and also for farmers so that they can better understand and appreciate the effect of each epidemic sub component on the final size of their crop loss.Simulators serve as tools that can evaluate the importance of the size of each epidemic sub component at a particular point in time of the epidemic by projecting its effect on the final crop loss.Computer simulation are expert systems,that try to equal and suppress the logic and ability of an expert professional in solving problems.Systems are used in plant pathology frequently for diagnosis of plant diseases.Systems can advice growers in making decisions on disease management in respect of kind, amount and time of application of pesticides etc.Simulators can decompose disease progress so they are used now to develop forecaster.
This document summarizes plant disease management through plant quarantine. It defines plant quarantine as legal restrictions on agricultural commodity movement to prevent the establishment of plants, pests, and diseases in new areas. It provides details on the history and organization of plant quarantine in India, including relevant laws and quarantine stations at airports, seaports, and land frontiers. The document lists some examples of diseases controlled by plant quarantine in India and introduces some foreign diseases introduced to India with the year and originating country.
Yellow vein mosaic virus is a devastating disease of okra (Abelmoschus esculentus) in India. It was first reported in India in 1924 and causes up to 80% crop loss if plants are infected early. The causal agent is a begomovirus transmitted by the whitefly Bemisia tabaci. Infected plants show a yellow vein pattern and stunting, and fruits are small and deformed. Management strategies include removing infected plants, controlling weed hosts, crop rotation, resistant varieties, and insecticide sprays.
The document discusses a study on the effect of different carbon sources on the production of hydrolytic enzymes in Trichoderma sp strains T13 and T14 and their ability to act as mycoparasites. Key findings include:
- Chitin was found to induce maximum production of chitinase, protease and beta-glucanase enzymes.
- T. reesei was able to produce hydrolytic enzymes like chitinase, protease and beta-glucanase when grown in soil in the presence of various fungal pathogens like Fusarium moniliforme, Fusarium solani, Rhizoctonia solani, Sclerotium rolfsii
Biological control is the suppression of one organism by another. There are two modes of mechanisms namely direct and indirect. Here I focused on the direct mechanisms such as parasitism, predatism, antibiotic-mediated suppression, lytic enzymes and unregulated-waste products. with the help of these various direct mechanisms, the bio-control agents will compete the pathogen's activity.
Different techniques for detection of plant pathogens.Zohaib Hassan
Plant pathology is the study of plant diseases. Major plant pathogens include fungi, bacteria, nematodes, and viruses. Techniques used to detect pathogens include histopathological examination of infected tissues, culture growth on media, staining, microscopy, and analysis of biochemical properties. Symptoms caused by pathogens can provide clues to identification. Isolation and purification of the pathogen allows for reinoculation to fulfill Koch's postulates.
This document discusses various methods for controlling plant diseases. The major methods discussed are cultural control methods, biological control methods, and chemical control methods. Cultural control methods include avoiding contact between the pathogen and host plant through proper field selection, resistant varieties, and modifying cultural practices. Biological control uses other organisms like fungi, bacteria, and mycorrhizal fungi to control pathogens. Chemical control involves the use of fungicides, bactericides, and other chemical treatments to directly kill or inhibit pathogens.
This document summarizes induced plant resistance against pathogens. It discusses the historical background of induced resistance being first observed over 100 years ago. It describes different types of induced resistance including systemic acquired resistance (SAR) and induced systemic resistance (ISR). SAR is mediated by salicylic acid and involves pathogenesis-related proteins, while ISR is mediated by jasmonic acid and ethylene. Biological agents like PGPR bacteria and plant extracts can also induce resistance. Signal transduction pathways underlying these responses are triggered upon pathogen recognition. While induced resistance offers opportunities for crop protection, practical applications are currently limited to some plants.
This ppt illustrates and describes the two bacterial diseases included in the BSc Hons Program Syllabys Core Course III or DSC 3- Citrus canker and angular leaf spot of cotton
Principles of plant disease managementRanjan Kumar
This document discusses principles of plant disease management. It explains that a plant disease is caused by the impairment of a plant's normal physiological functioning due to irritation from pathogens. Disease management aims to prevent disease incidence, reduce pathogen inoculum, and minimize crop losses. It does this by eliminating interactions between susceptible hosts, virulent pathogens, and suitable environments. The key principles of disease management are avoidance, exclusion, eradication, protection, use of resistant varieties, and therapy. Each principle is described in detail with examples.
This document summarizes the key principles of plant infection:
1) Penetration is the entry of the pathogen into the host, which can occur directly through the plant surface, through wounds, or through natural openings like stomata, hydathodes, or lenticels.
2) Infection is the establishment of the pathogen within the host plant by procuring nutrients from host cells or tissues.
3) Invasion is the spread of the pathogen within the host, which can be intercellular or intracellular depending on the type of pathogen.
4) Dissemination refers to the spread of the pathogen from one plant to another, which can occur autonomously through soil, seeds, or plant parts,
Development of transgenic plants for abiotic stress resistancetara singh rawat
The document discusses various genes that have been used to engineer abiotic stress tolerance in plants. It describes genes involved in synthesizing osmoprotectants like glycinebetaine and trehalose, antioxidant genes like superoxide dismutase, transcription factor genes like DREB1A, early response genes like ERD15, and genes that maintain membrane integrity and ion homeostasis. Engineering these stress-responsive genes into crop plants through genetic engineering approaches can help improve abiotic stress tolerance and food security.
SURVIVAL AND DISPERSAL OF PHYTOPATHOGENIC BACTERIA.pdfOm Prakash
SURVIVAL OF PHYTOPATHOGENIC BACTERIA
Phytopathogenic bacteria have the ability to survive both for longer & shorter periods including soil, seed, diseased crop debris, weed host, and insect vectors.
DISPERSAL OF PLANT PATHOGENIC BACTERIA
To make a healthy plant diseased, the first requirement of a pathogen is to spread its inoculum (primary as well as secondary) from the source of survival to the susceptible parts of a healthy plant. The spread of a plant pathogen within the general area in which it is already established is called “dispersal” or “dissemination”.
Moving the inoculum only a few inches and transporting it for hundreds of miles both constitute its dispersal or dissemination. However, pathogen dispersal is not necessary only for the spread of diseases but also for the continuity of the life-cycle and evolution of the pathogen. Detailed knowledge of pathogen-dispersal is essential to find out effective control measures for diseases because the possibilities of preventing dispersal and thereby breaking the infection chain always exist.
This document describes three types of symptoms caused by a bacterial disease in plants: 1) Seedling blight causes water-soaked spots on cotyledons that collapse and die. 2) Blackarm causes dark brown to black lesions on stems, petioles, and fruiting branches that crack and are easily broken. 3) Angular leaf spot causes small, dark-green spots on leaves that become angular, brown, and blackish as they enlarge and appear on both sides of the leaf. The bacterium can survive for years in soil and seed and spreads primarily through seed and secondarily through water, wind, and insects. Resistant varieties should be grown to manage the disease.
Importance of epidemics in mono and poly cyclic diseases caused by various plant pathogens and the mathematical models for studying the strategy of those epidemics
In this PPT you will come to know about the different types of mosaic virus which is caused in BHENDU crop, its life cycle, epidemiology, and its management.
The document discusses plant disease epidemics and epidemiology. It defines an epidemic as a disease that spreads rapidly to many individuals within an area over a short time period. Epidemiology is the study of epidemics and the factors that influence them, including the interaction between hosts, pathogens, environments, and human activities. For an epidemic to occur, there needs to be a susceptible host, a virulent pathogen, and favorable environmental conditions over an extended period of time. The interaction of these components can be visualized using a disease triangle or tetrahedron model. Examples of historical epidemics that caused famines are discussed.
The document discusses seed treatment methods for controlling seedborne diseases. It finds that treating rice seeds with manual cleaning and a 15% brine solution significantly reduced rice seedborne diseases like brown spot and bacterial leaf blight. This improved yields by 12-15% and seed quality, with fewer unfilled grains and discolored seeds. Another study evaluated treatments for controlling safflower seed and soilborne diseases. It found that treating seeds with the fungus Trichoderma harzianum greatly reduced disease incidence and severity of pathogens like Fusarium, yielding the highest seed production. A third abstract discusses using non-thermal plasma as a novel seed treatment method, finding it a potential alternative to conventional hot water, chlorine or fungicide
1. Subcutaneous mycoses are chronic fungal or bacterial infections of the subcutaneous tissues that can spread through the lymphatics or form sinus tracts. They are caused by organisms found in soil and are most common in tropical regions.
2. Mycetoma, also known as Madura foot, is a common subcutaneous mycosis characterized by a slowly progressive granulomatous infection of the skin and subcutaneous tissues of the extremities. It is caused by fungi like Madurella mycetomatis or bacteria like Actinomyces.
3. Diagnosis involves identification of fungal or bacterial grains from infected lesions through microscopic examination of potassium hydroxide mounts, staining techniques,
Classification of Fungi. Superficial Mycoses & Systemic Mycoses. Dermatophyte...Eneutron
This document discusses medical fungi that can cause superficial and systemic mycoses. It covers the general characteristics of fungi including their morphology, classification, and modes of infection. Specific types of mycoses are described such as dermatophytoses caused by fungi like Trichophyton that infect the skin, hair, and nails. Deeper mycoses like sporotrichosis that infect subcutaneous tissue via minor trauma are also outlined. The document provides details on laboratory diagnostics and culturing of different fungi as well as antifungal therapies.
Seed can harbor pathogens and soil contains organisms that attack seeds and seedlings. Treating seed with pesticides can improve stand quality, increase yields, and increase return on investment. It involves applying a pesticide to seeds to reduce disease organisms, insects, or other pests that attack seeds or seedlings during storage and after planting. Common seeds treated are corn, small grains, cotton, forage grasses, sorghum, soybeans and vegetables. Seed treatment involves properly applying precisely measured pesticide quantities to seeds using equipment that mixes the pesticide and gently coats the seeds uniformly.
Significance of seed borne diseases on crop production in bangladeshMd. Kamaruzzaman
This document discusses the significance of seed borne diseases on crop production in Bangladesh. It outlines several objectives related to understanding seed borne pathogens, annual crop losses, seed infection and management. It then provides definitions of seed and seed borne disease. The document lists examples of common seed borne diseases and their pathogens for various crops. It discusses the role of unhealthy seeds in issues like germination failure and introduces new diseases. Finally, it provides data on losses for several crops and pathogens due to factors like reduced germination and yields.
Organic matter provides numerous chemical, physical, and biological benefits to soil. Chemically, it acts as a reservoir of nutrients, contributes to the soil's cation exchange capacity, and forms chelates that make nutrients more available to plants. Physically, organic matter improves soil structure, increases the soil's water holding capacity, and prevents erosion. Biologically, it supports soil microorganisms that drive nutrient cycling and helps maintain overall soil quality.
This document provides information on 11 fungicides: Hexachlorobenzene, Carbendazim, Carboxin, Titraconazole, Validamycin, Epoxiconazole, Uniconazole, Pencycuron, Phosphite, Natamycin. It summarizes their chemical names, properties, uses, and mechanisms of action for controlling fungal infections in plants and foods.
The document discusses plant disease forecasting. It provides information on:
1. The principles of disease forecasting are based on the nature of the pathogen, environmental effects on pathogen development, host response to infection, and grower activities.
2. Models for disease prediction include empirical, simulation, and general circulation models, but these models have limitations due to uncertainty and non-linear relationships.
3. Disease forecasts are used for strategic decision making like crop selection and tactical decisions around disease management measures. Successful forecasting requires reliability, simplicity, importance of the disease, and usefulness.
Control of plant diseases can be achieved through various methods:
1. Breeding resistant plant varieties, using chemicals and altering the environment for protection, and implementing quarantine and regulatory measures to control the spread of diseases.
2. The amount of disease is determined by the interaction between the host, pathogen, and environment, known as the disease triangle. Control strategies aim to reduce one or more components of this interaction.
3. Common control methods include using resistant plant varieties, biological controls like antagonistic microorganisms, cultural practices that manipulate the environment, legislative controls on movement of plants/materials, and application of pesticides and fungicides.
Biological Control for Pest Disease Managementgreenjeans76
This document discusses biological control for plant disease management. It begins with introducing biological control products and their effectiveness, noting that understanding options and effectiveness is key to disease management. It then reviews factors that influence the effectiveness of biological control, finding that disease pressure, aerial vs soilborne diseases, and annual vs perennial crops do not significantly impact efficacy. Fungal and bacterial biocontrol agents and pathogens also show no difference in efficacy. The document dives deeper into analyzing specific products like Trichoderma spp., their active ingredients, uses, mechanisms of suppression, and evaluations. It finds products like RootShield with T. harzianum generally work well but may be affected by dry conditions and lack registration.
This document discusses subcutaneous mycoses, including mycetoma, sporotrichosis, and botryomycosis. It provides details on the causative agents, pathogenesis, clinical presentation, laboratory diagnosis, and treatment of each condition. Mycetoma is characterized by tumor-like lesions with draining sinuses and grains discharged from the skin. The causative organisms of mycetoma and actinomycetoma can be identified by examining the grains. Sporotrichosis typically presents as a chancre and lymphangitis following skin inoculation by Sporothrix schenckii. Botryomycosis is a chronic infection characterized by grape-like clusters of bacteria in subcutaneous tissue.
This document discusses plant pests, diseases, and disorders. It provides examples of common plant pests like mites, scale, aphids, and moths. It also discusses the four main types of plant pathogens - fungi, bacteria, viruses, and nematodes. Finally, it outlines methods for identifying, treating, and preventing plant pests and diseases, including cultural, physical, biological, and chemical controls.
This document provides a summary of soil microorganisms and their functions in 3 sentences or less:
Soil is teeming with life including bacteria, fungi, protists, and animals that carry out essential functions like decomposing organic matter, fixing nitrogen, and forming symbiotic relationships with plant roots. There can be thousands of species of microbes like bacteria and fungi, and dozens of species of larger organisms like earthworms, mites and nematodes in a single handful of healthy soil. These diverse soil microorganisms interact and carry out critical processes in the soil ecosystem that support plant growth and agricultural production.
This document provides an introduction to soil biology for students. It defines key terms like soil and dirt, and explains the five factors that influence soil formation: climate, organisms, relief, parental material, and time. It describes the different layers that make up a soil profile. The document also discusses the microbes, fungi, and animals that live in soil and their roles in decomposition and nutrient cycling. Students will learn about these topics over three weeks, including a 1.5 hour test and 2 hour practical.
This document discusses seed borne diseases and their management. It notes that seed borne pathogens can cause significant losses through reduced germination, seedling mortality, and yield losses. Some key seed borne diseases mentioned include late blight of potato, brown spot of rice, and downy mildew of pearl millet. The document then outlines methods for detecting seed borne pathogens, including visual examination, growing tests, and molecular methods. It discusses management approaches like seed selection, quarantine, hot water treatment, chemical seed treatments, and biological seed treatments using microbes like Trichoderma and Pseudomonas.
Subcutaneous mycoses are fungal infections that grow on soil or decaying vegetation. They must be introduced into subcutaneous tissue to cause disease. Lesions generally spread slowly from the area of implantation via lymphatics, except in cases of sporotrichosis where spread may be faster. Sporothrix schenckii is a dimorphic fungus that lives on plants or wood and causes sporotrichosis, a chronic granulomatous infection. Diagnosis involves culturing samples from lesions on Sabouraud's medium, where clusters of conidia indicate S. schenckii. Treatment includes oral antifungals like potassium iodide, amphotericin B, or ketocon
Este documento estudia el biocontrol de Fusarium spp. en el cultivo de tomate con Trichoderma spp. Se seleccionaron tres cepas de Trichoderma spp. nativas y se probaron varias concentraciones en cultivos duales con Fusarium spp., observándose control efectivo. En plantas de tomate, los tratamientos con las cepas LC2 y C-TY1 mostraron mayor peso seco y germinación. En el campo, el tratamiento C-TM4 tuvo menor mortalidad de plantas y mayor producción de frutos. Los resultados indican que
Power point presentation plant diseasesroshni17890
This document discusses several common plant diseases, their causes, symptoms, and prevention methods. It describes diseases that affect coconut (bud rot and root wilt caused by bacteria), paddy (blight disease caused by bacteria), rubber (decay disease caused by fungus), pepper (quick wilt caused by fungus), and plantain (bunchy top disease caused by a banana bunchy top virus spread by aphids). The concluding paragraphs emphasize that plant disease management aims to reduce economic and aesthetic damage by applying our growing scientific understanding of pathogen-host interactions and developing control measures tailored to specific diseases.
This document provides an introduction to the course PPATH 503: Epidemiology and Forecasting of plant disease. It defines key epidemiological concepts such as epidemic, epidemiology, monocyclic and polycyclic pathogens. It discusses how host, pathogen and environmental factors influence disease development. It also examines the history of epidemiology from ancient times to modern developments. Disease progress curves and mathematical modeling of epidemics are introduced.
IDENTIFICATION, DISTRIBUTION AND VECTOR BIOLOGY OF BROME MOSAIC VIRUS OF WHEA...Suresh Srivatsavai
This document describes a thesis submitted by Venkata Suresh Kumar Srivatsavai to Auburn University in partial fulfillment of the requirements for a Master of Science degree. The thesis investigated the identification, distribution, and vector biology of Brome mosaic virus (BMV) in wheat in Alabama. Wheat leaves were collected from different counties and tested for BMV using ELISA. BMV was found to be present throughout many counties in Alabama. Weeds and soil samples were also collected and tested, with Evening Primrose found to carry BMV. Flea beetles were shown to acquire and transmit BMV between wheat plants, suggesting they may be a vector.
This document provides information about plant virus taxonomy and classification. It discusses that taxonomy is the science of naming and classifying organisms, including plants, animals and microorganisms. Plant viruses are classified into six major groups based on their genome type, including single-stranded or double-stranded DNA or RNA. The majority of plant viruses fall into the positive sense single-stranded RNA group. Various characteristics such as morphology, genome properties, biological properties, and serological properties are used to further classify viruses into families, genera, and species. The International Committee on Taxonomy of Viruses (ICTV) develops and maintains the official taxonomy of plant viruses.
Virus_Classification of plant virus in virusReddykumarAv
Virus classification is the process of naming viruses and placing them into a taxonomic system similar to the classification systems used for cellular organisms. Viruses are classified by phenotypic characteristics, such as morphology, nucleic acid type, mode of replication, host organisms, and the type of disease
Virology is the study of viruses and virus-like agents, including their taxonomy, disease-producing properties, culture, and genetics. Viruses are non-cellular biological entities that consist of DNA or RNA genomes enclosed in a protein coat. They can only reproduce within living cells. Influenza is caused by RNA viruses of the Orthomyxoviridae family. There are three main types of influenza viruses - A, B, and C. Influenza A is further classified into subtypes based on surface proteins and can infect both humans and animals. Influenza causes respiratory illness with symptoms like fever, cough and sore throat. It spreads through respiratory droplets and the best prevention is an annual flu vaccine.
The document discusses two main schemes for classifying viruses: the International Committee on Taxonomy of Viruses (ICTV) system and the Baltimore classification system. The ICTV system is charged with developing and maintaining a universal virus taxonomy based on phenotypic characteristics. It establishes taxonomic ranks down to the species level. The Baltimore classification system groups viruses into seven categories based on their nucleic acid type and replication method.
This document provides an overview of mycoviruses. It discusses their history, taxonomy, structure, and classification. Key points include:
- Mycoviruses are viruses that infect fungi and were first observed in the 1940s associated with mushroom disease.
- They have diverse genomes that can be dsRNA, ssRNA, or DNA. Major families include Totiviridae, Partitiviridae, Chrysoviridae, and Megabirnaviridae.
- Mycovirus particles range in size from 30-80nm and have structures adapted to their genome organization, such as spherical or multilayered capsids.
- Mycoviruses can reduce fungal virulence, be
This document provides an overview of viruses and their classification. It discusses that viruses consist of nucleic acid in a protein coat and can only reproduce within living host cells. Viruses vary in size and shape. The document then covers the discovery of viruses and their distinctive properties compared to living cells. It discusses the nomenclature and classification of viruses, including how they are classified based on their genome, structure, and hosts. Classification systems discussed include the LHT and Baltimore systems.
1. The document provides an overview of pests that affect horticulture in Belize and their identification. It discusses the major groups of pests including viruses, bacteria, fungi, nematodes, insects, mites, molluscs, and weeds.
2. Symptoms and impacts of each pest group are outlined. Specific pests of concern in Belize are then described along with their symptoms and diagnostic characteristics.
3. Biological control methods for organic pest management are covered, including conservation of natural enemies like predators and parasitoids, and use of biopesticides like Bacillus thuringiensis and fungi.
This document provides a review of Potato virus Y (PVY). It discusses that PVY is a positive single-stranded RNA virus that infects potato and other solanaceous crops. The virus has a worldwide distribution and consists of three main strains (PVYO, PVYN, PVYC). PVY is transmitted by aphids in a non-persistent manner and can also be transmitted through grafting and sap inoculation. The virus causes significant losses in potato crops and is an important pathogen.
Coronaviruses are a family of viruses that cause disease in animals. Seven, including the new virus, have made the jump to humans, but most just cause cold-like symptoms.
Two other coronaviruses – Middle East respiratory syndrome (Mers) and severe acute respiratory syndrome (Sars) – are much more severe,
Molecular Plant Pathology - 2011 - SCHOLTHOF - Top 10 plant viruses in molecu...Abithadevi2
This document presents the results of a survey conducted by Molecular Plant Pathology to determine the top 10 most important plant viruses as voted on by plant virologists associated with the journal. The top 10 viruses were: 1) Tobacco mosaic virus, 2) Tomato spotted wilt virus, 3) Tomato yellow leaf curl virus, 4) Cucumber mosaic virus, 5) Potato virus Y, 6) Cauliflower mosaic virus, 7) African cassava mosaic virus, 8) Plum pox virus, 9) Brome mosaic virus, and 10) Potato virus X. The article provides a brief overview of each virus in the top 10 and their scientific and economic significance. It also mentions several other important viruses that just
The document summarizes the history of plant virology, beginning with Adolf Mayer's discovery in 1886 that sap from tobacco mosaic disease plants could transmit the disease. It then discusses the contributions of other scientists such as Ivanovsky, Beijerinck, Stanley, and Frankel who helped identify viruses as filterable agents and determine their protein and nucleic acid composition. The document also covers the economic importance of several major plant viruses including tobacco mosaic virus, potato leaf roll virus, cucumber mosaic virus, and banana bunchy top virus which can cause significant crop yield losses and damage industries.
Viruses are found wherever there is life and have probably existed since living cells first evolved. There are millions of different types of viruses, although only about 5,000 types have been described in detail. There are more than 219 virus species that are known to be able to infect humans. The document then provides a history of early developments in virology including discoveries by Louis Pasteur, Robert Koch, Edward Jenner, Dmitry Ivanovsky, Martinus Beijerinck, and others. It discusses the structure, composition and classification of viruses.
This document discusses various systems for classifying viruses. It begins by describing common properties used to classify viruses such as morphology, genome type, replication strategy, and host organisms. It then summarizes five major classification systems: Baltimore classification (based on mRNA synthesis strategy), Holmes classification (based on host organism), LHT classification (based on physical/chemical properties), Casjens and Kings classification (based on nucleic acid and structure), and ICTV classification (the current standard system maintained by the International Committee on Taxonomy of Viruses). The document also discusses classification based on nucleic acid type, number of genome strands, capsid structure, presence of an envelope, and host organism.
This study investigated the spontaneous induction of prophages in two species of Bradyrhizobium bacteria that form symbiotic relationships with soybeans. Bradyrhizobium elkanii USDA 76 and Bradyrhizobium diazoefficiens USDA 122 were cultured with and without chemical inducers. For USDA 76, viral abundances were considerably higher than bacterial abundances at all time points in the control treatment, indicating spontaneous prophage induction. However, inducer treatments resulted in lower viral abundances, suggesting the chemicals negatively impacted induction. In contrast, USDA 122 generally had more bacteria than viruses and low virus-to-bacteria ratios, regardless of treatment.
This document provides an overview of viruses, viroids, and prions. It discusses the general characteristics of viruses, including their small size, obligate intracellular parasitism, and nucleic acid genomes. It also describes virus classification systems, particularly the Baltimore classification system, which categorizes viruses based on their nucleic acid and replication strategy. Viroids are introduced as small, circular, single-stranded RNA plant pathogens that do not encode proteins. Prions are described as infectious protein particles that cause fatal neurodegenerative diseases in humans and cattle and contain no nucleic acids.
This document discusses viruses, including their structure, classification, and discovery. It notes that viruses consist of nucleic acid and a protein coat, and are able to multiply only within host cells. It describes some of the early discoveries of viruses in the late 19th century. It also summarizes different classification systems for viruses, including those based on nucleic acid type, structure, and genome, such as the Baltimore classification system. The document provides an overview of viruses with relevant details on their composition, life cycles, and taxonomic organization.
This document provides an introduction to viral classification. It discusses the early haphazard naming of viruses and several historical systems used for classification, including those based on disease association (Holmes), biological properties (ICTV), and replication strategy (Baltimore). The current ICTV system organizes viruses into orders, families, subfamilies, genera and species based on factors like virion structure, genome properties, proteins, and replication cycle. Proper classification allows viruses to be systematically named and organized into a taxonomic system.
Unraveling Virus Complexes in Plants/ CIAT APR 2015CIAT
This document summarizes the work of Wilmer J. Cuellar on unraveling virus complexes in plants. It discusses that viruses occur in complex communities and interact in various ways. Historically, plant viruses were described based on symptoms alone, but it is now understood that single strains grown in pure culture do not reflect reality. Viruses often occur as mixed infections in nature, and can have varying impacts depending on the plant variety infected. The document outlines research on complex virus infections in cassava and sweet potato. It emphasizes the importance of early identification and surveillance of potential virus threats. Improving diagnostic tools is key to evaluating cleaning protocols and detecting early infections. Understanding virus diversity and interactions is important for disease management.
The chemistry of the actinide and transactinide elements (set vol.1 6)Springer
Actinium is the first member of the actinide series of elements according to its electronic configuration. Actinium closely resembles lanthanum chemically. The three most important isotopes of actinium are 227Ac, 228Ac, and 225Ac. 227Ac is a naturally occurring isotope in the uranium-actinium decay series with a half-life of 21.772 years. 228Ac is in the thorium decay series with a half-life of 6.15 hours. 225Ac is produced from 233U with applications in medicine.
Transition metal catalyzed enantioselective allylic substitution in organic s...Springer
This document provides an overview of computational studies of palladium-mediated allylic substitution reactions. It discusses the history and development of quantum mechanical and molecular mechanical methods used to study the structures and reactivity of allyl palladium complexes. In particular, density functional theory methods like B3LYP have been widely used to study reaction mechanisms and factors controlling selectivity. Continuum solvation models have also been important for properly accounting for reactions in solvent.
1) Ranchers in Idaho observed lambs born with cyclopia (one eye) due to ewes grazing on corn lily plants. Cyclopamine was identified as the compound responsible and was later found to inhibit the Hedgehog signaling pathway.
2) Nakiterpiosin and nakiterpiosinone were isolated from cyanobacterial sponges and shown to inhibit cancer cell growth. Their unique C-nor-D-homosteroid skeleton presented synthetic challenges.
3) The authors developed a convergent synthesis of nakiterpiosin involving a carbonylative Stille coupling and a photo-Nazarov cyclization. Model studies led them to propose a revised structure for n
This document reviews solid-state NMR techniques that have been used to determine the molecular structures of amyloid fibrils. It discusses five categories of NMR techniques: 1) homonuclear dipolar recoupling and polarization transfer via J-coupling, 2) heteronuclear dipolar recoupling, 3) correlation spectroscopy, 4) recoupling of chemical shift anisotropy, and 5) tensor correlation methods. Specific techniques described include rotational resonance, dipolar dephasing, constant-time dipolar dephasing, REDOR, and fpRFDR-CT. These techniques have provided insights into the hydrogen-bond registry, spatial organization, and backbone torsion angles of amyloid fibrils.
This document discusses principles of ionization and ion dissociation in mass spectrometry. It covers topics like ionization energy, processes that occur during electron ionization like formation of molecular ions and fragment ions, and ionization by energetic electrons. It also discusses concepts like vertical transitions, where electronic transitions occur much faster than nuclear motions. The document provides background information on fundamental gas phase ion chemistry concepts in mass spectrometry.
Higher oxidation state organopalladium and platinumSpringer
This document discusses the role of higher oxidation state platinum species in platinum-mediated C-H bond activation and functionalization. It summarizes that the original Shilov system, which converts alkanes to alcohols and chloroalkanes under mild conditions, involves oxidation of an alkyl-platinum(II) intermediate to an alkyl-platinum(IV) species by platinum(IV). This "umpolung" of the C-Pt bond facilitates nucleophilic attack and product formation rather than simple protonolysis back to alkane. Subsequent work has validated this mechanism and also demonstrated that platinum(IV) can be replaced by other oxidants, as long as they rapidly oxidize the
Principles and applications of esr spectroscopySpringer
- Electron spin resonance (ESR) spectroscopy is used to study paramagnetic substances, particularly transition metal complexes and free radicals, by applying a magnetic field and measuring absorption of microwave radiation.
- ESR spectra provide information about electronic structure such as g-factors and hyperfine couplings by measuring resonance fields. Pulse techniques also allow measurement of dynamic properties like relaxation.
- Paramagnetic species have unpaired electrons that create a magnetic moment. ESR detects transition between spin energy levels induced by microwave absorption under an applied magnetic field.
This document discusses crystal structures of inorganic oxoacid salts from the perspective of periodic graph theory and cation arrays. It analyzes 569 crystal structures of simple salts with the formulas My(LO3)z and My(XO4)z, where M are metal cations, L are nonmetal triangular anions, and X are nonmetal tetrahedral anions. The document finds that in about three-fourths of the structures, the cation arrays are topologically equivalent to binary compounds like NaCl, NiAs, and FeB. It proposes representing these oxoacid salts as a quasi-binary model My[L/X]z, where the cation arrays determine the crystal structure topology while the oxygens play a
Field flow fractionation in biopolymer analysisSpringer
This document summarizes a study that uses flow field-flow fractionation (FlFFF) to measure initial protein fouling on ultrafiltration membranes. FlFFF is used to determine the amount of sample recovered from membranes and insights into how retention times relate to the distance of the sample layer from the membrane wall. It was observed that compositionally similar membranes from different companies exhibited different sample recoveries. Increasing amounts of bovine serum albumin were adsorbed when the average distance of the sample layer was less than 11 mm. This information can help establish guidelines for flow rates to minimize fouling during ultrafiltration processes.
1) The document discusses phonons, which are quantized lattice vibrations in crystals that carry thermal energy. It describes modeling crystal vibrations using a harmonic lattice approach.
2) Normal modes of the lattice vibrations can be described as a set of independent harmonic oscillators. Quantum mechanically, these normal modes are quantized as phonons with discrete energy levels.
3) Phonons can be thought of as quasiparticles that carry momentum and energy in the crystal lattice. Their propagation is described using a phonon field approach rather than independent normal modes.
This chapter discusses 3D electroelastic problems and applied electroelastic problems. For 3D problems, it presents the potential function method for solving problems involving a penny-shaped crack and elliptic inclusions. It derives the governing equations and introduces potential functions to obtain the general static and dynamic solutions. For applied problems, it discusses simple electroelastic problems, laminated piezoelectric plates using classical and higher-order theories, and piezoelectric composite shells. It also presents a unified first-order approximate theory for electro-magneto-elastic thin plates.
Tensor algebra and tensor analysis for engineersSpringer
This document discusses vector and tensor analysis in Euclidean space. It defines vector- and tensor-valued functions and their derivatives. It also discusses coordinate systems, tangent vectors, and coordinate transformations. The key points are:
1. Vector- and tensor-valued functions can be differentiated using limits, with the derivatives being the vector or tensor equivalent of the rate of change.
2. Coordinate systems map vectors to real numbers and define tangent vectors along coordinate lines.
3. Under a change of coordinates, components of vectors and tensors transform according to the Jacobian of the coordinate transformation to maintain geometric meaning.
This document provides a summary of carbon nanofibers:
1) Carbon nanofibers are sp2-based linear filaments with diameters of around 100 nm that differ from continuous carbon fibers which have diameters of several micrometers.
2) Carbon nanofibers can be produced via catalytic chemical vapor deposition or via electrospinning and thermal treatment of organic polymers.
3) Carbon nanofibers exhibit properties like high specific area, flexibility, and strength due to their nanoscale diameters, making them suitable for applications like energy storage electrodes, composite fillers, and bone scaffolds.
Shock wave compression of condensed matterSpringer
This document provides an introduction and overview of shock wave physics in condensed matter. It discusses the assumptions made in treating one-dimensional plane shock waves in fluids and solids. It briefly outlines the history of the field in the United States, noting that accurate measurements of phase transitions from shock experiments established shock physics as a discipline and allowed development of a pressure calibration scale for static high pressure work. It describes some of the practical applications of shock wave experiments for providing high-pressure thermodynamic data, understanding explosive detonations, calibrating pressure scales, and enabling studies of materials under extreme conditions.
Polarization bremsstrahlung on atoms, plasmas, nanostructures and solidsSpringer
This document discusses the quantum electrodynamics approach to describing bremsstrahlung, or braking radiation, of a fast charged particle colliding with an atom. It derives expressions for the amplitude of bremsstrahlung on a one-electron atom within the first Born approximation. The amplitude has static and polarization terms. The static term corresponds to radiation from the incident particle in the nuclear field, reproducing previous results. The polarization term accounts for radiation from the atomic electron and contains resonant denominators corresponding to intermediate atomic states. The full treatment allows various limits to be taken, such as removing the nucleus or atomic electron, reproducing known results from quantum electrodynamics.
Nanostructured materials for magnetoelectronicsSpringer
This document discusses experimental approaches to studying magnetization and spin dynamics in magnetic systems with high spatial and temporal resolution.
It describes using time-resolved X-ray photoemission electron microscopy (TR-XPEEM) to image the temporal evolution of magnetization in magnetic thin films with picosecond time resolution. Results are presented showing the changing domain structure in a Permalloy thin film following excitation with a magnetic field pulse. Different rotation mechanisms are observed depending on the initial orientation of the magnetization with respect to the applied field.
A novel pump-probe magneto-optical Kerr effect technique using higher harmonic generation is also discussed for addressing spin dynamics in magnetic systems with femtosecond time resolution and element selectivity.
This document discusses nanomaterials for biosensors and implantable biodevices. It describes how nanostructured thin films have enabled the development of more sensitive electrochemical biosensors by improving the detection of specific molecules. Two common techniques for creating nanostructured thin films are described - Langmuir-Blodgett films and layer-by-layer films. These techniques allow for the precise control of film thickness at the nanoscale and have been used to immobilize biomolecules like enzymes to create biosensors. Recent research is also exploring how these nanostructured films and biomolecules can be used to create implantable biosensors for real-time monitoring inside the body.
Modern theory of magnetism in metals and alloysSpringer
This document provides an introduction to magnetism in solids. It discusses how magnetic moments originate from electron spin and orbital angular momentum at the atomic level. In solids, electron localization determines whether magnetic properties are described by localized atomic moments or collective behavior of delocalized electrons. The key concepts of metals and insulators are introduced. The document then presents the basic Hamiltonian used to describe magnetism in solids, including terms for kinetic energy, electron-electron interactions, spin-orbit coupling, and the Zeeman effect. It also discusses how atomic orbitals can be used as a basis set to represent the Hamiltonian and describes the symmetry properties of s, p, and d orbitals in cubic crystals.
This chapter introduces and classifies various types of damage that can occur in structures. Damage can be caused by forces, deformations, aggressive environments, or temperatures. It can occur suddenly or over time. The chapter discusses different damage mechanisms including corrosion, excessive deformation, plastic instability, wear, and fracture. It also introduces concepts that will be covered in more detail later such as damage mechanics, fracture mechanics, and the influence of microstructure on damage and fracture. The chapter aims to provide an overview of damage types before exploring specific mechanisms and analyses in later chapters.
This document summarizes research on identifying spin-wave eigen-modes in a circular spin-valve nano-pillar using Magnetic Resonance Force Microscopy (MRFM). Key findings include:
1) Distinct spin-wave spectra are observed depending on whether the nano-pillar is excited by a uniform in-plane radio-frequency magnetic field or by a radio-frequency current perpendicular to the layers, indicating different excitation mechanisms.
2) Micromagnetic simulations show the azimuthal index φ is the discriminating parameter, with only φ=0 modes excited by the uniform field and only φ=+1 modes excited by the orthogonal current-induced Oersted field.
3) Three indices are used to label resonance
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slackshyamraj55
Discover the seamless integration of RPA (Robotic Process Automation), COMPOSER, and APM with AWS IDP enhanced with Slack notifications. Explore how these technologies converge to streamline workflows, optimize performance, and ensure secure access, all while leveraging the power of AWS IDP and real-time communication via Slack notifications.
GraphRAG for Life Science to increase LLM accuracyTomaz Bratanic
GraphRAG for life science domain, where you retriever information from biomedical knowledge graphs using LLMs to increase the accuracy and performance of generated answers
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
Fueling AI with Great Data with Airbyte WebinarZilliz
This talk will focus on how to collect data from a variety of sources, leveraging this data for RAG and other GenAI use cases, and finally charting your course to productionalization.
Trusted Execution Environment for Decentralized Process MiningLucaBarbaro3
Presentation of the paper "Trusted Execution Environment for Decentralized Process Mining" given during the CAiSE 2024 Conference in Cyprus on June 7, 2024.
Skybuffer AI: Advanced Conversational and Generative AI Solution on SAP Busin...Tatiana Kojar
Skybuffer AI, built on the robust SAP Business Technology Platform (SAP BTP), is the latest and most advanced version of our AI development, reaffirming our commitment to delivering top-tier AI solutions. Skybuffer AI harnesses all the innovative capabilities of the SAP BTP in the AI domain, from Conversational AI to cutting-edge Generative AI and Retrieval-Augmented Generation (RAG). It also helps SAP customers safeguard their investments into SAP Conversational AI and ensure a seamless, one-click transition to SAP Business AI.
With Skybuffer AI, various AI models can be integrated into a single communication channel such as Microsoft Teams. This integration empowers business users with insights drawn from SAP backend systems, enterprise documents, and the expansive knowledge of Generative AI. And the best part of it is that it is all managed through our intuitive no-code Action Server interface, requiring no extensive coding knowledge and making the advanced AI accessible to more users.
Skybuffer SAM4U tool for SAP license adoptionTatiana Kojar
Manage and optimize your license adoption and consumption with SAM4U, an SAP free customer software asset management tool.
SAM4U, an SAP complimentary software asset management tool for customers, delivers a detailed and well-structured overview of license inventory and usage with a user-friendly interface. We offer a hosted, cost-effective, and performance-optimized SAM4U setup in the Skybuffer Cloud environment. You retain ownership of the system and data, while we manage the ABAP 7.58 infrastructure, ensuring fixed Total Cost of Ownership (TCO) and exceptional services through the SAP Fiori interface.
Nunit vs XUnit vs MSTest Differences Between These Unit Testing Frameworks.pdfflufftailshop
When it comes to unit testing in the .NET ecosystem, developers have a wide range of options available. Among the most popular choices are NUnit, XUnit, and MSTest. These unit testing frameworks provide essential tools and features to help ensure the quality and reliability of code. However, understanding the differences between these frameworks is crucial for selecting the most suitable one for your projects.
Digital Marketing Trends in 2024 | Guide for Staying AheadWask
https://www.wask.co/ebooks/digital-marketing-trends-in-2024
Feeling lost in the digital marketing whirlwind of 2024? Technology is changing, consumer habits are evolving, and staying ahead of the curve feels like a never-ending pursuit. This e-book is your compass. Dive into actionable insights to handle the complexities of modern marketing. From hyper-personalization to the power of user-generated content, learn how to build long-term relationships with your audience and unlock the secrets to success in the ever-shifting digital landscape.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
We will explore the capabilities of AI in understanding XML markup languages and autonomously creating structured XML content. Additionally, we will examine the capacity of AI to enrich plain text with appropriate XML markup. Practical examples and methodological guidelines will be provided to elucidate how AI can be effectively prompted to interpret and generate accurate XML markup.
Further emphasis will be placed on the role of AI in developing XSLT, or schemas such as XSD and Schematron. We will address the techniques and strategies adopted to create prompts for generating code, explaining code, or refactoring the code, and the results achieved.
The discussion will extend to how AI can be used to transform XML content. In particular, the focus will be on the use of AI XPath extension functions in XSLT, Schematron, Schematron Quick Fixes, or for XML content refactoring.
The presentation aims to deliver a comprehensive overview of AI usage in XML development, providing attendees with the necessary knowledge to make informed decisions. Whether you’re at the early stages of adopting AI or considering integrating it in advanced XML development, this presentation will cover all levels of expertise.
By highlighting the potential advantages and challenges of integrating AI with XML development tools and languages, the presentation seeks to inspire thoughtful conversation around the future of XML development. We’ll not only delve into the technical aspects of AI-powered XML development but also discuss practical implications and possible future directions.
Taking AI to the Next Level in Manufacturing.pdfssuserfac0301
Read Taking AI to the Next Level in Manufacturing to gain insights on AI adoption in the manufacturing industry, such as:
1. How quickly AI is being implemented in manufacturing.
2. Which barriers stand in the way of AI adoption.
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2. 56 2 Identification and Taxonomic Groups
2.1 Identification
In order to detect and identify a seed-transmitted
virus, it is imperative to understand the
characteristics of seed-transmitted viruses for
comparison with the available information on
previously described viruses. Diagnosis of a
virus disease is never unequivocal unless the
virus is isolated, studied outside its host and
demonstrated by Koch’s postulates. By following
the ‘ten commandments of the plant viruses’
proposed by Bos (Bos 1976a), a reasonable
diagnosis of the viral disease could be made.
The diagnosis begins with particulars of the
diseased plant and then deals with the virus
itself, indicating a gradual shift from clinical
observations to etiological diagnosis.
The pragmatic approach depends on the fact
that each virus has a definite host range that is
often confined to a wide or limited number of
host plants. The natural hosts of the virus are
first identified and a comparison is then made
with previously isolated species or their close
relatives, and their properties are also compared
with those of the unknown virus. Based on the
morphology of the virus involved, they can easily
be differentiated by their shape and size. Serology
and nucleic acid hybridisation tests are being
widely used for the identification of different
plant viruses and their strains. At present the
virus identification is being done in scientific
laboratories through specialised techniques. Dif-
ferent steps involve are seed morphology, indi-
cator hosts, transmission, electron microscopy,
serology, molecular methods, etc., which can help
in detection and identification of seed-transmitted
viruses. The total list of conventional viruses,
cryptic viruses and viroids which are seed trans-
mitted and reported from different parts of the
world is presented in Table 1.2.
2.2 Classification of Viruses
In the early period of plant virus research work,
inadequate identification has lead to lot of con-
fusion due to lack of an internationally accepted
classification of plant viruses. Looking into this
problem, Bos (1964) suggested the use of stan-
dardised vernacular names while listing out the
viruses from legume crops. Subsequent schemes
of nomenclature (Gibbs and Harrison (1976);
Matthews (1979, 1982); Fauquet et al. (2005);
King et al. (2011) and grouping Harrison et al.
(1971); Francki (1981)) of viruses and the recent
CMI/AAB descriptions have contributed greatly
to the knowledge of plant viruses. During 1996,
Brunt and his associates’ compiled publication
is one of the most important sources of descrip-
tions of viruses of tropical plants. Information on
the identification of virus diseases in the form
of Virus Information Data Exchange (VIDE) is
published by Boswell and Gibbs 1986 and Gibbs
1989. A system called ‘DELTA’ which is specif-
ically designed to handle all forms of taxonomic
information has been used to store the informa-
tion in computers (Brunt et al. 1996).
The taxonomic approach assesses the group
to which a virus belongs by determining some
of its group-specific characteristics such as the
shape and size of its particles. Then, more spe-
cific tests including host range are used to check
whether the unknown virus is an already de-
scribed member of the likely group or not. This
approach requires some understanding in virus
classification. Modern taxonomic classification is
also taken into the consideration of molecular
characterisation of viruses which has become
reliable and authentic (Van Regenmortal et al.
2000; Fauquet et al. 2005; King et al. 2011). The
ICTV 9th report of 2009 which was published by
King et al. (2011) has 6 orders, 87 families, 19
subfamilies, 349 genera and 2,284 species.
Based on a set of characteristics, more than
975 plant viruses have been described and clas-
sified by International Committee on Taxonomy
of Viruses (ICTV) into 34 well-defined groups
and a few less well-defined groups or subgroups
(Hamilton et al. 1981; Brown 1989; Martelli
1992; Brunt et al. 1996; Fauquet et al. 2005; Van
Regenmortel et al. 2005; King et al. 2011).
In the Table 1.2, available information
on seed-transmitted virus diseases of fruits,
vegetable and ornamental crops, including in
collateral hosts, was listed along with percentage
of seed transmission. In Table 2.1 taxonomic
position of seed-transmitted plant viruses is
8. 62 2 Identification and Taxonomic Groups
Table 2.1 (continued)
S. no Species (virus/viroid) Order Family Genus
213 Melon rugose mosaic Tymovirales Tymoviridae Tymovirus
214 Potato Andean latent Tymovirales Tymoviridae Tymovirus
215 Turnip yellow mosaic Tymovirales Tymoviridae Tymovirus
216 Sunflower rugose mosaic – Luteoviridae Umbravirus
217 Cherry necrotic rusty mottle Tymovirales Betaflexiviridae Unassigned
218 Potato virus T Tymovirales Betaflexiviridae Unassigned
219 Strawberry latent ring spot Picornavirales Secoviridae Unassigned
220 High plains virus – – Unassigned
221 Urdbean leaf crinkle (Syn.)
Black gram leaf crinkle (Syn.)
bean urd leaf crinkle virus
– – Unassigned
222 Barley mottle mosaic – – Unassigned
223 Brinjal ring mosaic – – Unassigned
224 Brinjal severe mosaic – – Unassigned
225 Carrot motley leaf – – Unassigned
226 Cherry ring spot – – Unassigned
227 Cineraria mosaic – – Unassigned
228 Mung bean isometric yellow
mosaic
– – Unassigned
229 Parsley latent – – Unassigned
230 Peanut marginal chlorosis – – Unassigned
231 Soybean mild mosaic – – Unassigned
presented by taking the information from Fauquet
et al. (2005) and King et al. (2011) classification
tables. The seed-transmitted viruses are confined
to 34 virus groups, which are in Table 2.2. To
have more clarity, the information on a particle
morphology and genome and vector is also
provided.
Among these plant virus groups, 231 well-
characterised seed-transmitted viruses are
distributed in 24 virus groups including Al-
famovirus, Bromovirus, Capillovirus, Carlavirus,
Carmovirus, Caulimovirus, Comovirus, Cryp-
tovirus, Cucumovirus, Enamovirus, Fabavirus,
Furovirus, Hordeivirus, Ilarvirus, Necrovirus,
Nepovirus, Potexvirus, Potyvirus, Sobe-
movirus, Tobamovirus, Tobravirus, Tombusvirus,
Tospovirus and Tymovirus groups. Greater
number of seed-transmitted viruses are found
in Potyvirus (35), Nepovirus(28), Cryptovirus
(28), Ilarvirus (14), Tobamovirus (7), Po-
texvirus (7), Comovirus (6), Carlavirus (5),
Carmovirus (5), Cucumovirus (5), Sobemovirus
(5), Furovirus (4), Bromovirus (3) and Tymovirus
(3) groups (Tables 2.1 and 2.2). On the other
hand, in some groups such as Alfamovirus,
Capillovirus, Caulimovirus, Enamovirus,
Fabavirus, Hordeivirus, Necrovirus, Tobravirus,
Tombusvirus and Tospovirus groups, the seed-
transmitted viruses recorded were very few. No
seed transmission was noticed in Closterovirus,
Dianthovirus, Geminivirus, Luteovirus, Parsnip
yellow fleck virus, Reovirus, Rhabdovirus,
Tenuivirus and Waikavirus groups.
2.3 Variability in Certain
Seed-Transmitted Viruses
From the above discussed aspects on plant virus
taxonomy, it is clear that the viruses resembling
each other in genome properties and virion mor-
phology are grouped into genera and given genus
names. The phylogenic analysis of some of the
viruses indicates that recently described viruses
are established based on molecular studies as
strains of the earlier described viruses. More
11. References 65
examples one can find are in potyvirus group.
Viruses like Blackeye cowpea mosaic and Peanut
stripe virus are nothing but strains of the Bean
common mosaic virus with little variation. Vari-
ability in viruses is noticed in almost all described
virus groups. The molecular structure of viruses
has the capacity of transferring its characters to
its duplicates produced in the host cells.
(a) Hybridisation: This is one of the means by
which new virus strains are formed. If two
strains of virus are inoculated into the same
host plant, one or more new virus strains
may be recovered with properties (virulence,
symptomatology, etc.) different from those of
either of the original strains introduced into
the host. These new strains are probably hy-
brids (RNA or DNA recombinants). Albersio
et al. (1975) reported variability in Squash
mosaic virus (SqMV) by hybridisation be-
tween two strains of virus. They had crossed
strain 1 H and II A of SqMV in pumpkin
(Cucurbita pepo) and cantaloupe (Cucumis
melo) plants and observed the interaction
between them.
(b) Mutations: The evolution of new strains of
viruses may also be due to mutation. These
may be a heritable change in the genetic
material (RNA or DNA). The production of
mutants differing in virulence has also been
reported in several viruses, especially TMV,
although they seem to vary mostly in the
type of symptoms and severity of disease they
produce rather than in their ability to infect
different host plant varieties.
The previous reports when the advanced iden-
tification techniques were not available have re-
ported very negligible (<1%) percentage of seed
transmission in certain virus–host combinations,
which the later research workers have disproved.
Without any discrimination based on the avail-
able literature all the seed-transmitted viruses,
Cryptoviruses and viroid diseases were reported
in the Tables 1.2, 2.1 and 2.2.
In the earlier days, when the computer
knowledge was not available, the students,
research workers and others used to depend
on Review of Plant Pathology, review articles
and other abstract journals for locating subject
literature for use in their research work. Since
1990, lot of databases and websites are available
which are quite useful for day-to-day plant
virus research work, where even the poor
library facilities existed and such problems were
solved by certain international organisations. For
example, the ‘Crop Protection Compendium’
(CPC), which was available on CD-ROM,
was published by CAB International, which
is being updated annually on http://www.
cabicompendium.org/cpc. Another valuable
information source for viruses is of AAB
descriptions on plant viruses and can be accessed
on http://www.dpvweb.net. Even the descriptions
and lists from VIDE Database of the International
Committee on Taxonomy of Viruses are available
on http://www.ncbi.nlm.nih.gov/ICTVdb/index.
htm. ‘The Plant Pathology Internet Guide Book’
(http://www.pk.uni-bonn.de/ppigb/ppigb.htm) is
another source of information for many virology
topics. Because of the availability of databases
of plant viruses on internet, it has become much
easier for the virus research workers to know the
latest progress that is happening in any corners of
the world (http://www.virology.net).
References
Albersio J, Lima A, Nelson MR (1975) Squash mosaic
virus variability: nonreciprocal cross-protection be-
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Bos L (1964) Tentative list of viruses reported from nat-
urally infected leguminous plants. Neth J Plant Pathol
70:161–174
Bos L (1976a) Problems and prospects in plant virus
identification. EPPO Bull 6:63–90
Bos L (1976b) Research on plant virus diseases in the
developing countries: possible ways for improvement.
FAO Plant Prot Bull 24(4):109–118
Boswell K, Gibbs A (1986) The VIDE data bank
for plant viruses. In: Jones RAC, Torrance L
(eds) Developments and applications in virus test-
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Brown F (1989) The classification and nomenclature of
viruses. Summary of results of meetings of Interna-
tional Committee on Taxonomy of Viruses. Edmonton,
Canada 1987. Intervirology 30:181–186
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Brunt AA, Crabtree K, Dallwitz MJ, Gibbs AJ, Watson
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