This document provides an introduction to phytopathology, including definitions, objectives, concepts of disease, components of disease, causes of diseases, classifications of diseases, symptoms, and control of plant diseases. Specifically, it defines phytopathology as the study of plant diseases. The objectives are described as etiology, pathogenesis, epidemiology, and control. Disease is defined as a physiological disorder or structural abnormality that reduces a plant's economic value. The components of disease that make up the disease triangle are a susceptible host, virulent pathogen, and favorable environment. Causes can be living (e.g. fungi, bacteria) or non-living (e.g. nutrient deficiencies). Diseases are classified based on extent
Effect of environment and nutrition on plant disease developmentparnavi kadam
BRIEF AND PRECISE POINTS ON PLANT DISEASE DEVELOPMENT. IT MOSTLY FOCUSES ON HOW THE FACTORS AFFECT THE MICROBES AND THEN THEIR MICROBIAL EFFECT ON DISEASE DEVELOPMENT.
Effect of environment and nutrition on plant disease developmentparnavi kadam
BRIEF AND PRECISE POINTS ON PLANT DISEASE DEVELOPMENT. IT MOSTLY FOCUSES ON HOW THE FACTORS AFFECT THE MICROBES AND THEN THEIR MICROBIAL EFFECT ON DISEASE DEVELOPMENT.
In this slide you will get all the important information of epidemiology.
For more information you can see my youtube channel
https://www.youtube.com/channel/UCUsmJMc2xvL3O3UkDh8knrA
In this slide you will get all the important information of epidemiology.
For more information you can see my youtube channel
https://www.youtube.com/channel/UCUsmJMc2xvL3O3UkDh8knrA
INOCULUM DYNAMICS, POPULATION BIOLOGY OF PATHOGENsunilsuriya1
**Inoculum Dynamics and Population Biology of Plant Pathogens:**
The study of inoculum dynamics and the population biology of plant pathogens is integral to understanding the patterns of disease spread, severity, and persistence in agricultural ecosystems. Here's a closer look at these concepts:
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**1. Inoculum Dynamics:**
- **Definition:** Inoculum refers to the source of pathogenic organisms that initiate disease. This can include spores, mycelium, seeds, or any other form of the pathogen that can infect a susceptible host.
- **Sources:** Inoculum can come from various sources, including infected plant debris, soil, seeds, insects, and other infected plant material. Understanding the sources and availability of inoculum is crucial for predicting disease outbreaks.
- **Seasonal Fluctuations:** Inoculum levels often fluctuate seasonally due to changes in environmental conditions. For instance, certain pathogens may produce more spores during periods of high humidity or temperature.
- **Survival and Dispersal:** Pathogens have evolved various strategies for survival and dispersal. Some pathogens can survive for extended periods in soil or on plant debris, while others rely on wind, water, insects, or human activity for dispersal to new host plants.
- **Quantification:** Methods for quantifying inoculum levels include spore trapping, soil sampling, and molecular techniques such as PCR (Polymerase Chain Reaction) assays.
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**2. Population Biology of Plant Pathogens:**
- **Population Growth:** Pathogens exhibit characteristic population growth patterns influenced by factors such as host availability, environmental conditions, and pathogen biology. The growth rate of a pathogen population depends on the rate of reproduction, dispersal, and host infection.
- **Epidemiological Patterns:** Pathogen populations often follow classic epidemiological patterns, including exponential growth, peak incidence, and decline. This is influenced by factors such as host susceptibility, pathogen virulence, and environmental suitability.
- **Host-Pathogen Interactions:** The dynamics of pathogen populations are shaped by interactions with host plants. Host resistance mechanisms, such as genetic resistance or induced systemic resistance, can reduce pathogen populations, while susceptible hosts can fuel pathogen growth.
- **Genetic Diversity:** Pathogen populations can exhibit genetic diversity, leading to differences in virulence, pathogenicity, and the ability to overcome host resistance. This genetic variability influences disease dynamics and the effectiveness of control measures.
- **Adaptation and Evolution:** Pathogens have the ability to adapt to changing environmental conditions and host defenses through natural selection. This can lead to the emergence of new strains or races with increased virulence or the ability to overcome resistant plant varieties.
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**Significance and Applications:**
- **Disease Prediction:**
This power-point presentation related to the importance, objectives & scope of plant pathology. This is a brief guide for the students looking for to choose the Plant Pathology as their field of study. I hope you will like it.
This pdf contains information about resistance breeding especially focused on the bachelor of agriculture student.
generally, resistance plant breeding pdf purpose is to provide the free notes for the student to enhance the knowledge to the upper level.
it is like a note pdf, which provides an easy way to read, learn, and understand the respective subject of resistance breeding, techniques and equipment as well as method.
especially for bachelor level students.
A detailed project on plant diseases,causes, symptoms and control measures with illustrations. The project explains in brief fungal and bacterial and and their control measures.Blast disease, citrus canker and leaf mosaic disease of tapioca are explained in detail. Non - infectious diseases are also mentioned.
"Bio - Warfare During Host Pathogen Interactions in Indigenous Crop Plants" b...Md. Kamaruzzaman
This is a analysis of some collected information of the subject of my M.S. theory semester. Course title was Plant Pathogenesis and Genetics of Plant Pathogens
Prayers and sacrifices to gods for control of plant diseases
The mid-1600s, a species or variety was reported to be more resistant to a disease than another related species or variety.
Selection of resistant plants as a control of plant diseases.
This is likely to have occurred not only because seeds from resistant and therefore healthier plants looked bigger and better than those from infected susceptible plants, but also because in severe disease out breaks, resistant plants were the only ones surviving and, therefore, their seeds were the only ones available for planting.
Similar to Introduction to phytopathology concepts, components and causes (20)
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
2. PHYTOPATHOLOGY
• Phytopathology is also known as plant pathology
• Pathology is a term made up of two gr. Words pathos= suffering;
logos= to study or discourse, thus plant pathology is the study of
suffering or diseases of plants
3. OBJECTIVES
• Etiology- causal organism, living or non living entity responsible for causing
diseases in plants
• Pathogenesis- disease development or host pathogen interaction
• Epidemiology- also called as epiphytotics in case of plant diseases.
• It is a wider term and includes plant, pathogen, environment, carryover of
pathogen to the next season and again spread and dispersal of disease
• Control –devising suitable methods to control, reduce or minimise the losses
due to pathogen
4. CONCEPT OF DISEASE
• According to Stakman and Harrar a disease can be defined as a
physiological disorder or structural abnormality that is deleterious to
the plant or any of its parts or products that reduces their economic
value
• Disease is any departure from normal health
• It is a malfunctioning or pathological process resulting in suffering
5. COMPONENTS OF DISEASE
• 3 components
• Susceptible host, virulent & aggressive pathogen , favourable
environment
• These 3 components constitute the disease triangle
• FOURTH FACTOR-TIME-an important factor of plant disease.
6. CAUSES OF DISEASES
• 1. animate or living caused by bacteria, fungi, algae,
nematodes, insects, virus and mycoplasmas
• 2. inanimate or non-living due to nutrition deficiency, deficiency
in nutrient contents of soil, excessive use of insecticide or plant
protecting chemicals
8. ON THE BASIS OF EXTENT TO WHICH
DISEASE ARE ASSOCIATED WITH PLANT
• 1. Localised disease- limited to a definite area
• 2. Systemic disease- spreads through the entire plant
9. ON THE BASIS OF MODE OF PRIMARY
INFECTION
1 soil borne
2 air- borne
3. Seed borne
10. ACCORDING TO THE TYPE OF HOST PLANT
Field crop
disease
Vegetable
disease
Fruit
disease
Forest
disease
Ornamental
plant
11. SYMPTOMS CAN BE BROADLY DIVIDED
INTO 3 CATEGORIES
symptoms
necrosis
hypertrophy
hyperplasia
13. HYPERTROPHY-ABNORMAL INCREASE IN
THE SIZE OF ORGAN
1. Elongated internodes
2. Galls and tumors
3. Witches broom
4. Curls
5. Floral abnormalities
14. HYPERPLASIA- ABNORMAL INCREASE IN
NUMBER OF CELLS DUE TO CELL DIVISION
1. Chlorosis
2. Reduction of individual organ
3. Floral abnormalities
15. CONTROL OF PLANT DISEASES
• Methods of plant disease control are generally classified on the basis
of nature of agent employed to control the disease:-
1regulatory 2 cultural 3 physical
4 chemical 5 biological
