KATTE DISEASE AND LEAF BLIGHT OF CARDAMOM . pptxVISHALI SELVAM
FOR DOWNLOAD CONTACT - eduvish24@gmail.com
KATTA DISEASES AND LEAF BLIGHT OF CARDAMOM
This presentation about “Katte/ Marble/ Mosaic”, is one of the major diseases in Cardamom that has resulted in a reduction in their production. The katte or mosaic disease in cardamom is caused by Cardamom Mosaic Virus (CdMV).Leaf blight of cardamom, popularly known as Chenthal was first reported from Vandanmedu village of Idukki district in Kerala.The disease mainly affects foliage and by destroying the effective photosynthetic aren, it adversely affects fruit set and capsule weight. Chenthal results in a yield reduction of 7-13% in Mysore type of cardamom.
Presentation on preventive measures of weed control.pptxSudha Neupane
Weeds have been known since the ancient times. Weed are unwanted plant that grow along with the main crop in the field. Weed are considered as cumbersome for successful agriculture production. Due to crop-weed competition the crop yield losses are generally high in agriculture production. So, in order to minimize such losses farmers are practicing several weed management strategies which includes prevention, eradication, control (mechanical, cultural, biological and chemical method). The cultural methods are expensive and time consuming so, farmer have to move towards other alternative methods of weed control Varga et.al (2000). Furthermore, due to rising labor cost and non-availability of labor for manual weeding during the critical period of weed control has contributed to use of herbicides. Herbicides not only timely and effectively controls the weed but also offer a great scope for minimizing the cost of production Varga et.al (2000). Control methods are applied after the emergence of weed on the field while prevention methods of weed control are adopted before sowing the crops. Generally, there are two objectives: 1. To prevent the entry and establishment of weed species in an area.2. To prevent the spread of weed or to limit the weed build up in a field.
These objectives are referred as prevention. And any method that are applied before sowing the crop to prevent there entry , establishment and spreads comes under the prevention category. Focusing on second objective of preventive measures of weed control we can say that some cultural methods such as crop rotation or crop diversification, stale seed bed, tillage system, cover crops ( used as green manures or dead mulches),soil solarization, irrigation and drainage systems and crop residues managements can be included under preventive methods of weed control. In practice, weed management strategies should integrate indirect (preventive) methods with direct (cultural and curative) methods. The first category includes any method used before a crop is sown, while the second includes any methods applied during a crop growing cycle. Methods in both categories can influence either weed density (i.e., the number of individuals per unit area) and/or weed development (biomass production and soil cover). However, while indirect methods aim mainly to reduce the numbers of plants emerging in a crop, direct methods also aim to increase crop competitive ability against weeds.The success of prevention depends on awareness of the problem, species, effort, Co-operation, area.
•Most effective where adopted against a single species on a large area on a cooperative basis.
In conclusion we can say that farmers have several preventive methods in their arsenal that they can put together to build up a good weed management strategy. Preventive weed control is permanent weed control and usually require community action. it. For this process, a collective or joint effort and commitment is required.
Doctoral seminar: Management of viral diseases in pulses and oilseedsHarshvardhan Gaikwad
PL.PATH-691 (Doctoral seminar), I presented on topic: Management of viral diseases in pulses and oilseeds. In which, I explained virus, history of virus, classification of plant virus, different viral diseases of pulses and oilseed crops, their management and three case studies. As we know that, virus always alters its genetic material and it is difficult and tedious to manage plant viral diseases.
KATTE DISEASE AND LEAF BLIGHT OF CARDAMOM . pptxVISHALI SELVAM
FOR DOWNLOAD CONTACT - eduvish24@gmail.com
KATTA DISEASES AND LEAF BLIGHT OF CARDAMOM
This presentation about “Katte/ Marble/ Mosaic”, is one of the major diseases in Cardamom that has resulted in a reduction in their production. The katte or mosaic disease in cardamom is caused by Cardamom Mosaic Virus (CdMV).Leaf blight of cardamom, popularly known as Chenthal was first reported from Vandanmedu village of Idukki district in Kerala.The disease mainly affects foliage and by destroying the effective photosynthetic aren, it adversely affects fruit set and capsule weight. Chenthal results in a yield reduction of 7-13% in Mysore type of cardamom.
Presentation on preventive measures of weed control.pptxSudha Neupane
Weeds have been known since the ancient times. Weed are unwanted plant that grow along with the main crop in the field. Weed are considered as cumbersome for successful agriculture production. Due to crop-weed competition the crop yield losses are generally high in agriculture production. So, in order to minimize such losses farmers are practicing several weed management strategies which includes prevention, eradication, control (mechanical, cultural, biological and chemical method). The cultural methods are expensive and time consuming so, farmer have to move towards other alternative methods of weed control Varga et.al (2000). Furthermore, due to rising labor cost and non-availability of labor for manual weeding during the critical period of weed control has contributed to use of herbicides. Herbicides not only timely and effectively controls the weed but also offer a great scope for minimizing the cost of production Varga et.al (2000). Control methods are applied after the emergence of weed on the field while prevention methods of weed control are adopted before sowing the crops. Generally, there are two objectives: 1. To prevent the entry and establishment of weed species in an area.2. To prevent the spread of weed or to limit the weed build up in a field.
These objectives are referred as prevention. And any method that are applied before sowing the crop to prevent there entry , establishment and spreads comes under the prevention category. Focusing on second objective of preventive measures of weed control we can say that some cultural methods such as crop rotation or crop diversification, stale seed bed, tillage system, cover crops ( used as green manures or dead mulches),soil solarization, irrigation and drainage systems and crop residues managements can be included under preventive methods of weed control. In practice, weed management strategies should integrate indirect (preventive) methods with direct (cultural and curative) methods. The first category includes any method used before a crop is sown, while the second includes any methods applied during a crop growing cycle. Methods in both categories can influence either weed density (i.e., the number of individuals per unit area) and/or weed development (biomass production and soil cover). However, while indirect methods aim mainly to reduce the numbers of plants emerging in a crop, direct methods also aim to increase crop competitive ability against weeds.The success of prevention depends on awareness of the problem, species, effort, Co-operation, area.
•Most effective where adopted against a single species on a large area on a cooperative basis.
In conclusion we can say that farmers have several preventive methods in their arsenal that they can put together to build up a good weed management strategy. Preventive weed control is permanent weed control and usually require community action. it. For this process, a collective or joint effort and commitment is required.
Doctoral seminar: Management of viral diseases in pulses and oilseedsHarshvardhan Gaikwad
PL.PATH-691 (Doctoral seminar), I presented on topic: Management of viral diseases in pulses and oilseeds. In which, I explained virus, history of virus, classification of plant virus, different viral diseases of pulses and oilseed crops, their management and three case studies. As we know that, virus always alters its genetic material and it is difficult and tedious to manage plant viral diseases.
Exclusion is one of the most important principles of plant disease management. It is the practice of preventing the introduction of pathogens into a region, farm, or planting. This can be done by a variety of methods, including:
* **Quarantine:** This is the practice of preventing the movement of plants, plant products, and other materials that may be infected with a pathogen from an area where the pathogen is present to an area where it is not present.
* **Inspection:** This is the process of checking plants and plant products for the presence of pathogens. Inspection can be done at ports of entry, on farms, and at other points along the transportation chain.
* **Certification:** This is the process of verifying that plants and plant products meet certain standards for freedom from pathogens. Certification is typically done by a government agency or a private organization.
* **Eradication:** This is the process of eliminating a pathogen from an area. Eradication is often used in conjunction with quarantine and inspection to prevent the spread of pathogens.
In addition to these methods, there are a number of other things that can be done to exclude pathogens from plant populations. These include:
* **Cleaning and disinfecting equipment:** Equipment that is used to handle plants, such as tools, machinery, and vehicles, can be a source of pathogens. Cleaning and disinfecting this equipment can help to prevent the spread of pathogens.
* **Using resistant cultivars:** Some cultivars of plants are resistant to certain pathogens. Planting these cultivars can help to reduce the risk of disease.
* **Good cultural practices:** Good cultural practices, such as crop rotation, sanitation, and weed control, can help to create an environment that is less favorable for the development of plant diseases.
Exclusion is an important part of an integrated approach to plant disease management. By using a combination of methods, it is possible to reduce the risk of plant diseases and protect crop yields.
Here are some additional examples of how exclusion can be used to manage plant diseases:
* **Growing plants in a greenhouse:** This can help to prevent the introduction of pathogens from the outside environment.
* **Using certified seed:** This ensures that the seed is free from pathogens.
* **Inspecting plants for pests and diseases before purchase:** This can help to prevent the introduction of pathogens into a new planting.
* **Quarantining new plants:** This can help to prevent the spread of pathogens from infected plants to healthy plants.
Exclusion is not always possible, but it is an important tool in the fight against plant diseases. By using exclusion methods, it is possible to reduce the risk of disease and protect crop yields.
Characteristics of pet/virus , plant disease , pest life cycle, regarding and repeating plant disease , selecting treatment methods, Control plant pest / virus .
Exclusion is one of the most important principles of plant disease management. It is the practice of preventing the introduction of pathogens into a region, farm, or planting. This can be done by a variety of methods, including:
* **Quarantine:** This is the practice of preventing the movement of plants, plant products, and other materials that may be infected with a pathogen from an area where the pathogen is present to an area where it is not present.
* **Inspection:** This is the process of checking plants and plant products for the presence of pathogens. Inspection can be done at ports of entry, on farms, and at other points along the transportation chain.
* **Certification:** This is the process of verifying that plants and plant products meet certain standards for freedom from pathogens. Certification is typically done by a government agency or a private organization.
* **Eradication:** This is the process of eliminating a pathogen from an area. Eradication is often used in conjunction with quarantine and inspection to prevent the spread of pathogens.
In addition to these methods, there are a number of other things that can be done to exclude pathogens from plant populations. These include:
* **Cleaning and disinfecting equipment:** Equipment that is used to handle plants, such as tools, machinery, and vehicles, can be a source of pathogens. Cleaning and disinfecting this equipment can help to prevent the spread of pathogens.
* **Using resistant cultivars:** Some cultivars of plants are resistant to certain pathogens. Planting these cultivars can help to reduce the risk of disease.
* **Good cultural practices:** Good cultural practices, such as crop rotation, sanitation, and weed control, can help to create an environment that is less favorable for the development of plant diseases.
Exclusion is an important part of an integrated approach to plant disease management. By using a combination of methods, it is possible to reduce the risk of plant diseases and protect crop yields.
Here are some additional examples of how exclusion can be used to manage plant diseases:
* **Growing plants in a greenhouse:** This can help to prevent the introduction of pathogens from the outside environment.
* **Using certified seed:** This ensures that the seed is free from pathogens.
* **Inspecting plants for pests and diseases before purchase:** This can help to prevent the introduction of pathogens into a new planting.
* **Quarantining new plants:** This can help to prevent the spread of pathogens from infected plants to healthy plants.
Exclusion is not always possible, but it is an important tool in the fight against plant diseases. By using exclusion methods, it is possible to reduce the risk of disease and protect crop yields.
Characteristics of pet/virus , plant disease , pest life cycle, regarding and repeating plant disease , selecting treatment methods, Control plant pest / virus .
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
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.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
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 .
1. SRI PARAMAKALYANI COLLEGE
( REACCREDITEDWITH B GRADE WITH A CGPA OF 2.71 IN THE II CYCLEBY NAAC
AFFILIATED TO MANONMANIAMSUNDARANAR UNIVERSITY, TIRUNELVELI)
ALWARKURICHI627 412
POST GRADUATE & RESEARCHCENTRE – DEPARTMENT OF MICROBIOLOGY
(GOVERNMENT AIDED)
II SEM – CORE – VIROLOGY
UNIT III – COMMON VIRAL DISEASES OF CROP PLANT
SUBMITTED TO SUBMITTED BY,
DR. C. MARIAPPAN , PH.D, S. SARAL BEEVI,
ASSISTANT PROFESSOR, REG NO: 20211232516123,
SRI PARAMAKALYANI COLLEGE, SRI PARAMAKALYANI COLLEGE,
ALWARKURCHI. ALWARKURCHI.
2. OUTLINE
- Plant virus
- Common plant viral diseases
- Pathogen
- Symptoms
-Treatment
- Prevention
- Control
3. PLANT VIRUS
• Plant viruses are viruses that affect plants. Like all other viruses, plant
viruses are obligate intracellular parasites that do not have the molecular
machinery to replicate without a host. Plant viruses can be pathogenic to
higher plants.
5. RICE TUNGRO DISEASE : RICE TUNGRO VIRUS (RTSV, RTBV)
• Rice tungro disease is caused by the combination of two viruses, which are
transmitted by leafhoppers. It causes leaf discoloration, stunted growth,
reduced tiller numbers and sterile or partly filled grains. Tungro infects
cultivated rice, some wild rice relatives and other grassy weeds commonly
found in rice paddies.
6. PATHOGEN
• Two morphologically unrelated viruses present in phloem cells. Rice tungro
bacilliform virus (RTBV) bacilliform capsid, circular ds DNA genome and
Rice tungro spherical virus (RTSV) isometric capsid ss RNA genome.
7. SYMPTOMS
• Infection occurs both in the nursery and main field.
• Plants are markedly stunted.
• Leaves show yellow to orange discoloration and interveinal chlorosis.
• Young leaves are sometimes mottled while rusty spots appear on older
leaves. Tillering is reduced with poor root system.
• Panicles not formed in very early infection, if formed, remain with few,
deformed and chaffy grains.
8. TREATMENT
• Light traps are to be set up to attract and control the leaf hopper vectors
as well as to monitor the population.
• In the early morning, the population of leafhopper alighting near the light
trap should be killed by spraying/dusting the insecticides. This should be
practiced every day.
9. • Spray Two rounds of any one of the following insecticides
• Thiamethoxam 25 WDG 100g/ha
• Imidacloprid 17.8 SL 100ml/ha
• at 15 and 30 days after transplanting. The vegetation on the bunds should
also be sprayed with the insecticides.
10. PREVENTIVE MEASURES
• Plant more resistant varieties if available.
• Plant early to avoid peaks populations of this insect.
• Remove weeds in and around the field.
• Control insecticides in order not to affect beneficial insects.
• Plow under infected plant residues or better burn them.
• Alternatively, destroy infected plants after harvest.
11. CONTROL
• Organic Control
• Light traps have successfully been used to attract and control the green
leafhopper vectors as well as to monitor the population. In the early
morning, the population of leafhopper alighting near the light trap should
be caught and disposed of, alternatively killed by spraying/dusting
insecticides. This should be practiced every day.
• Destroy infected plants and plow under infected plant residues or better
burn them.
12. • Chemical control
• Always consider an integrated approach with preventive measures together
with biological treatments if available. Spraying insecticides based on
buprofezin or pymetrozine at 15 and 30 days after transplanting can work
if done in a timely manner. However, the insects can move to surrounding
fields and spread tungro rapidly in very short times. Therefore, the
vegetation around the field should also be sprayed with the insecticides.
13. • Avoid products based on chlorpyriphos, lamda cyhalothrin or other
synthetic pyrethroid combinations, to which the leafhoppers have become
partly resistant.
• Spraying insecticides can suppress the populations of the green
leafhoppers which means it will reduce the speed of spreading the virus.
Some known insecticides can be used to control green leafhoppers.
14. RICE YELLOW MOTTLE DISEASE
• Rice yellow mottle virus is a plant pathogenic virus, belonging to the genus
Sobemovirus. The genome is a positive-sense single strand RNA of 4450
nucleotides in length and is not polyadenylated.
• Mottling usually consists of yellowish spots on plants, and is usually a sign of
disease or malnutrition.
15. PATHOGEN
• Rice yellow mottle virus (RYMV) caused by Solemoviridae is a major biotic
factor affecting rice production and continues to be an important pathogen
in SSA. To date, six pathogenic strains have been reported. RYMV infects
rice plants through wounds and rice feeding vectors.
16. SYMPTOMS
• Younger leaves are mottled with yellow to green spots.
• After infection (2 weeks) these spots elongate parallel
to the leaf veins.
• In the center of the yellow streaks, dark patches develop.
• Older leaves show yellow or orange discoloration. The
growth of the plants can be stunted and the yield is reduced.
17. TREATMENT
• Employ the use of large-scale synchronous planting combined with fallow
period to prevent the buildup of the virus and vector.
• plow under-infected crop residues, volunteer rice, infected ratoons,
alternate hosts of the virus, and the vector immediately after harvest to
reduce the primary inoculum in the field and prevent continuous survival of
the virus and the vector.
18. • Establish the crop before the increase in the vector population.
• Roguing and burning infected plants, especially when infection is still low.
• Regular weeding during the cropping season and even after harvest to
reduce sources of primary inoculum.
19. PREVENTIVE MEASURES
• Resistant and tolerant varieties are available.
• Using nursery sites which haven’t been infected previously or direct sowing
in the field can also help prevent the spread of the virus.
• Planting the crop as early as possible can avoid the peak period of insect
vectors of the virus. In addition, synchronising the planting in different fields
can prevent the virus from spreading to younger crops.
20. • Maintaining weeds to control other hosts of the virus and clearing bushes
around fields to control breeding sites for insect vectors can also prevent
RYMV spread.
• Sanitation procedures can reduce the spread of RYMV. CABI recommends
cleaning weeds from irrigation canals and around rice fields, especially
during the off season, to remove the virus and its insect vectors will remove
the virus and insect vectors.
21. • Cleaning of farm machinery can reduce spread prevent mechanical
spread. This also applies to cleaning any farm machinery after each use.
22. CONTROL
• RYMV will completely kill susceptible varieties; if detected, removing
infected plants and destroying them can prevent further spread. It has also
been reduce the application of fertiliser on infected plants.
• There are no chemical control methods to directly stop the spread of RYMV.
However, there are available insecticides to control vectors of the virus in
some countries; suitable chemicals vary depending on country specific
guidelines.
23. COMMON PLANT VIRAL DISEASES IN COTTON
• Leaf crumple
• Leaf curl
• Leaf mottle
• Leaf role
24. LEAF MOTTLE DISEASE
• A zinc deficiency disease is characterized by a partial chlorosis, reduced
size of leaves and fruits, and stunting
• A virus disease is characterized by chlorotic mottling, puckering, distortion,
and wrinkling of the leaves
25. PATHOGEN
• The leaf mottle viral disease was transmitted by grafting to other XL.l
plants and to X1730 A and Domains Sakel, identical symptoms appearing
on all 3.
26. SYMPTOMS
• The primary symptom of cotton leaf mottle virus is the
upward curling of leaves.
• Additionally, leaf veins can thicken and darken, and
outgrowths (enactions) may form on the undersides of
leaves, typically in the shape of leaves.
• Flowers may stay closed and then drop along with the bolls.
If plants are infected early in the season, their growth will be
stunted and yield will be reduced significantly.
27. TREATMENT
• Although there are virtually no antiviral compounds available to cure plants
with viral diseases.
• Efficient control measures can greatly mitigate or prevent disease from
occurring.
• Virus identification is a mandatory first step in the management of a
disease caused by a virus.
28. PREVENTIVE MEASURES
• Use certified disease-free seeds and ensure transplants are healthy.
• Control whitefly populations and protect seedlings in particular from them.
• Ensure a weed-free field and surroundings.
• Practice crop rotation by not planting cotton near alternative hosts.
• Plow under or burn all plant debris after harvest.
29. CONTROL
• Organic Control
• Whitefly populations can generally be controlled by natural enemies (e.g.
lacewings, bigeyed bugs, minute pirate bugs), so be careful not to kill them
with rampant spraying of chemical pesticides.
• Neem oil or petroleum-based oils can be used and should thoroughly cover
the plants, particularly the undersides of leaves.
30. • Recent research has also indicated the potential of using biocontrol agents
such as beneficial isolated bacterial strains (Bacillus, Pseudomonas and
Burkholderia) as a means of reducing the incidence of the virus.
• Chemical Control
• Always consider an integrated approach with preventive measures together
with biological treatments if available.
31. • There are no known methods for preventing or reducing cotton leaf curl
virus. Chemical control in the form of insecticides can be used to control the
whitefly population, such as imadacloprid or dinotefuran.
• Insecticides should be approached with caution however, because excessive
usage of insecticides has caused many whitefly species to become resistant
to them. To reduce the likelihood of this occurring, be sure to rotate between
insecticides.
33. TOMATO MOSAIC VIRAL DISEASE
• It is a kind of plant virus with worldwide distribution and has a wide range
of hosts, which can not only infect Solanaceae, Cruciferae, and other
vegetable crops, but also infect flowers and seedlings, etc.
34. PATHOGEN
• ToMV is a positive-sense, single-stranded RNA virus belonging to the
Virgaviridae family, Tobamovirus genus.
35. SYMPTOMS
• It Seen as a general mottling or mosaic appearance on foliage.
• Light and darker green mosaic leaf mottle, sometimes with distortion
of younger leaves; this is the most common reaction in summer in
glasshouses.
• In winter, with low light intensity, short days and temperatures not
above 20°C, plants are often severely stunted and leaves distorted
to ‘fern-leaf’ or tendril shape, but mottling may be slight.
36. • Plants are less vigorous, and fruit yield is reduced by 3 to 23%. Tomato
mosaic virus strains occur in Chenopodium murale , causing severe stunting,
distortion and necrosis , and in pear associated with a diffuse chlorotic leaf
spotting.
37. TREATMENT
• Remove diseased plants from the field as soon as virus symptoms are
noticed. This will reduce the spread of the virus by direct contact between
plants.
• Work in diseased areas last after working in unaffected parts of a field.
Wash clothing that comes into contact with ToMV-infected plants with hot
water and a detergent.
38. • Disinfect tools, stakes, and equipment before moving from diseased areas
to healthy areas. This can be done by:
• (1) heating or steaming at 150°C for 30 minutes.
• (2) soaking 10 minutes in 1% formaldehyde or 0.1% sodium hypochloride.
39. PREVENTIVE MEASURES
• Keep weeds controlled within and around the garden site, as these may be
alternate hosts for whiteflies.
• Reflective mulches (aluminum or silver-colored) can be used in the rows to
reduce whitefly feeding.
• Spot treat with least-toxic, natural pest control products, such as Safer
Soap, Bon-Neem, and diatomaceous earth, to reduce the number of
disease-carrying insects.
40. • Harvest-Guard row cover will help keep insect pests off vulnerable crops/
transplants and should be installed until bloom.
• Remove all perennial weeds, using least-toxic herbicides, within 100 yards
of your garden plot.
• The virus can be spread through human activity, tools, and equipment.
Frequently wash your hands and disinfect garden tools, stakes, ties, pots,
greenhouse benches, etc. (one part bleach to 4 parts water) to reduce the
risk of contamination.
41. • Avoid working in the garden during damp conditions (viruses are easily
spread when plants are wet).
• Avoid using tobacco around susceptible plants. Cigarettes and other
tobacco products may be infected and can spread the virus.
• Remove and destroy all infected plants (see Fall Garden Cleanup). Do not
compost
42. CONTROL
• Remove all infected plants and destroy them. Do not put them in the
compost pile, as the virus may persist in infected plant matter. Burn infected
plants or throw them out with the garbage.
• Monitor the rest of your plants closely, especially those that were located
near infected plants.
• Disinfect gardening tools after every use. Keep a bottle of a weak bleach
solution or other antiviral disinfectant to wipe your tools down with.
43. CUCUMBER MOSAIC VIRUS (CMV) DISEASE
• Cucumber mosaic virus (CMV) is one of the most common plant viruses,
causing yellow mottling, distorted leaves and stunted growth in a wide
range of garden plants, not just cucumbers.
44. PATHOGEN
• CMV is a linear positive-sense, single stranded RNA virus.
• It consist of three spherical particles each approximately 28 nm in
diameter. One particle containing RNA 1, another containing RNA 2, third
containing RNA 3.
• Each RNA molecule’ js enclosed within a protective protein coat.
45. SYMPTOMS
• Yellowish patches or green and yellow mottling on leave.
• Leaves curl downwards and are distorted and reduced in
size.
• Plants are stunted due to a shortening of the internodes
(lengths of stem between leaves.
• Reduction in yields and distorted fruit.
• In flowers white streaks known as ‘breaks’ appear.
46. TREATMENT
• Infected plants should be removed and destroyed to eliminate the plants as
potential reservoirs for the virus (which can subsequently be spread to other
nearby healthy plants).
• Infected plants can be burned (where allowed by local ordinance), deep
buried or hot composted.
• Killing infected plants with herbicides can also be an effective management
strategy.
47. PREVENTIVE MEASURES
• Use crop rotation.
• Eradicate weeds and volunteer tomato plants.
• Space plants to not touch, mulch plants, fertilize properly.
• Don’t wet tomato foliage with irrigation water, and keep the plants growing
vigorously.
• Trim off and dispose of infected lower branches and leaves.
48. CONTROL
• CULTURAL METHOD
• There is no perfect control for this virus.
• Removing weeds and diseased plants from fields can reduce the chance of
infection.
• Early planting of crops reduce aphids infestation.
49. • CHEMICAL METHOD
• Spray dimethoate:
• 2mlM/lit or Monocrotophos
• 1.5 mlM/lit to control insect vectors.
• Spray of mineral oil in plants to control aphids.
51. SUGARCANE MOSAIC VIRUS
• Sugarcane mosaic virus (SCMV) is a plant pathogenic virus of the family
Potyviridae.
• As a viral infection, mosaic disease cannot be controlled by fungicides or
other pesticides. In some cases infection leads to severe damage. In the
worst cases, the disease may kill the entire lawn as the turfgrass declines.
This is referred to as lethal viral necrosis (LVN).MV
52. PATHOGEN
• Sugarcane mosaic virus (Marmor sacchari) is present in abundance in the
chlorotic lesions of the affected leaves.
• It belongs to the potato virus Y group.
• It causes varying degrees of destruction of the
chlorophyll, and hence the chlorotic symptom.
53. • The virus particles are rods, measuring in the range of 650-770x 12-15
pm.
• Several strains of the virus, designated as A,B,C,D,E,F and H and a few sub-
strains have been differentiated, based on their physical properties and
virulence.
54. SYMPTOMS
• SCMV causes systemic infection of the sugarcane plant: the whole plant,
including roots, contains virus.
• However, the symptoms (mosaic and/or necrosis) are observed on the
leaves and sometimes th.e stems.
• The disease appears more prominently on the basal portion of the
younger foliage as chlorotic or yellowish stripes alternate with normal
green portion of the leaf.
55. • As infection becomes severe, yellow stripes appear on the leaf sheath and stalks.
• Elongated necrotic lesions are produced on the stalks and stem
splitting occurs.
• The necrotic lesions also develop on the internodes and the
entire plant becomes stunted and chlorotic.
• Sometimes the whole plant is stunted and chlorotic, easily
dentified from a distance.
56. TREATMENT
• To minimize spread of sugarcane mosaic virus all equipment used should be
sanitized.
• Fungicides and other pesticides have been shown to be ineffective when
dealing with viral disease.
• The best way to deal with a viral disease is through plant host resistance.
57. PREVENTIVE MEASURES
• Disease free cane should be used as setts.
• Diseased plants should be dug as & burnt.
• Low lying areas avoided for cultivation.
• A 2-3 years rotation should be followed.
• Ratooning should be avoided.
• Use of resistant varieties, eg. Isward 254 Isward 1-16 Isward 1-17, etc.,
58. CONTROL
• Altering the times of planting and harvesting so that they do not coincide
with high aphid vector populations can reduce losses.
• Eradicate SCMV by roguing infected plants have rarely been successful.
• Saccharum spontaneum L. and S. barberi (Jesweit) carry resistance to mosaic
and so varieties with this background must be preferred.
• The spontaneum canes from java posses a high degree of resistance to
mosaic.
59. • The use of resistant varieties is the most effective method of mosaic control.
• Planting mosaic-free seed cane is essential.
• Rogue out the diseased clumps periodically. Select setts from the healthy
fields as the virus is sett-bome Aerated Steam Therapy (AST) at 56°C for 3
hrs, for setts before planting is advised.