The document discusses various plant diseases including late blight of potato, late blight of tomato, downy mildew of cucurbits, downy mildew of grapes, and their symptoms, causes, and management. It introduces Tiger fungicide as a new active ingredient and mode of action to control these diseases. Tiger effectively controls diseases at different stages of the pathogen's lifecycle and prevents resistance development when used in combination with contact fungicides. Proper application timing and correct doses of Tiger provide long-lasting protection of crops from diseases.
8. One of the most devastating disease in human history
Caused great Irish famine during 1845 – 47
1.0 million people died and similar no. of people migrated from Ireland to USA & Europe
Till today it is basis of research for chemical companies to discover new
chemical
Late Blight - PotatoLate Blight - Potato
9. Small water-soaked lesions appear on the leaf margins - grow into large
purplish black necrotic lesions and cover the leaf
On the lower surface of the leaf, whitish downy growth below the lesion
Late Blight - PotatoLate Blight - Potato
10. Lower leaves are affected first and then the infection spreads to healthy
leaves
Late Blight - PotatoLate Blight - Potato
11. Late blight also appears on the stem and
the affected stem becomes weak &
collapses above the lesion causing death
of the plant.
Defoliated plants in the infected areas
render a patchy look of the field.
Late Blight - PotatoLate Blight - Potato
12. Excessive humidity above 80% & temperature of around 15-20 C,
wind and rain splashes.
High soil moisture, dew drops & dip in night temperature facilitate disease
spread.
Late Blight - PotatoLate Blight - Potato
16. Late Blight of TomatoLate Blight of Tomato
Lesions start as irregular, greenish, water-soaked spots on leaves, petioles,
and/or stems
17. lesions first appear on the leaves
Late Blight of TomatoLate Blight of Tomato
18. Close-up of leaf with late blight, whitish fungal growth is characteristic of late
blight. Look for it early-morning while relative humidity is high.
Late Blight of TomatoLate Blight of Tomato
19. Late blight infected tomato leaf. Note
the brown, shriveled, dried area.
Late blight infected tomato plant with
dead, brown leaves and stem.
Late Blight of TomatoLate Blight of Tomato
20. Stems and fruit show evidence of late blight
Late Blight of TomatoLate Blight of Tomato
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21.
22. Early lesions of downy mildew usually appear water-soaked on the underside
of leaves.
Downy Mildew in CucurbitsDowny Mildew in Cucurbits
23. Cucurbits – Downy MildewCucurbits – Downy Mildew
downy mildew lesions usually do not enlarge beyond major veins, giving
spots an angular appearance.
24. Downy Mildew in CucurbitsDowny Mildew in Cucurbits
Downy Mildew
Yellow spots on the upper surface of the leaves are early symptoms of downy
mildew.
25. Dark purplish gray spores of the
downy mildew fungus only
develop on lower surfaces of
leaves and are easily distinguished
from white spores of fungus.
These spores are diagnostic but
unfortunately are not always
present
Downy Mildew in CucurbitsDowny Mildew in Cucurbits
26. Lower surface of pumpkin leaf affected by downy mildew lacking the
pathogen’s characteristic purplish gray sporulation.
Diagnostic spores may form when an affected leaf is placed with damp paper
towel in a closed paper for 12-24 hours.
Downy Mildew in CucurbitsDowny Mildew in Cucurbits
28. Leaf tissue affected by downy mildew can change quickly from yellow to
brown as it is killed.
Downy Mildew in CucurbitsDowny Mildew in Cucurbits
29. Downy Mildew
These are not diagnostic as similar spots can occur with other diseases,
notably powdery mildew
Downy Mildew in CucurbitsDowny Mildew in Cucurbits
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30.
31. What is downy mildew ?
Downy mildew - GrapesDowny mildew - Grapes
32. Downy mildew - GrapesDowny mildew - Grapes
Lesions are yellowish and oily on the upper surface of leaf with a whitish
downy growth on the corresponding lower surface.
33. Downy mildew - GrapesDowny mildew - Grapes
Primary infection from the oospores and dormant mycelia of the host tissues.
Secondary spread by the sporagia and zoospores.
34. Downy mildew - GrapesDowny mildew - Grapes
The infected portion of leaves turns brown and can not support the growing
bunch
35. Downy mildew - GrapesDowny mildew - Grapes
Mildew growth may cover the entire leaf blade which turns brown and
withers.
36. Downy mildew - GrapesDowny mildew - Grapes
Young berries are highly susceptible becomes grayish covered with a downy
felt of fungus.
40. Active Ingredient : Dimethomorph (DMM)
Chemical Group - Cinnamic Acid derivative
Formulation: 50% WP
Highly effective against Oomycetes
Long duration control
Tiger - Introduction
41. # 4 great benefits of Tiger!!
Cell wall lysis
Effective against different
stages of fungal lifecycle
Translaminar Action
Antisporulant
Packs Doses
42. DMM disintegrates cell wall to kill the
pathogen. This mode of action is unique
MEANS BETTER EFFICACY
1
Tiger – Cell wall Lysis
43. Tiger : Acts at different stages in life cycle
NO SCAPE FOR DOWNY MILDEW !
2
45. Good uptake into sprayed leaves
translaminar from upper to lower leaf surface
and within the leaf towards the tip and margins
Treated
leaf
Redistributi
on of radio-
active
labeled
Dimethomor
ph in the
plant
3 DAT 7 DAT
Locally
systemic
Redistribution of Tiger in Grapevine
47. Doses
CROP Diseases Dose per acre
Potato Late blight 200g Tiger + 600 g Mancozeb
or
200g Tiger + 600 g COC
CROP Diseases Dose per acre
Tomato Late blight 200g Tiger + 600 g Mancozeb
or
200g Tiger + 600 g COC
48. CROP Diseases Recommendation Dose per acre
Grapes Downy
Mildew
at 4 - 5 Leaf stage
at 5 - 7 Leaf stage
at 7 - 10 Leaf
stage
200g Tiger + 500 g
Mancozeb/COC
225g Tiger + 600 g
Mancozeb/COC
250g Tiger + 800 g
Mancozeb/COC
Doses
CROP Diseases Recommendation Dose per acre
Cucurbits Downy
Mildew
At initial disease
stages
200g Tiger +
600 g Mancozeb
Or
200g DMM +
600 g COC
50. Selection for ResistanceSelection for Resistance
Initial Population Resistant Population
Survivor Population
Reproduction
The development of Practical Resistance is a step-wise process
Naturally
occurring resistant
individual
51. Fungicide Alternation / +ves of mixtures
Prevents repeated selection for resistant individuals
A B
Fungicide B indiscriminately controls Fungicide A - resistant
individuals and vice-versa
Alternation must be with fungicides having
different MOA’s!!!
53. Why should I mix Tiger with Mancozeb or COC ?
Tiger is a systemic fungicide and should always be used in combination with
contact fungicides, Mancozeb or COC as part of resistance management
strategy.The combination of systemic and contact activity on the Late Blight
pathogen prevents it from developing resistance.
What if it rains after application of Tiger?
Tiger enters inside the leaf within 2 hours after application due to its
translaminar activity and continues to protect your crop from inside.
Will Tiger have any adverse effect on growth of the
plant ?No. Tiger is absolutely safe for the plant, it helps in retaining green
foliage by effectively controlling the disease.
FAQs
54. When should I use Tiger?
Tiger should be used before or coinciding with disease onset, as preventive
treatment against Late Blight of Potato. Benefit from using tiger are maximized
when it is applied in the early spray rounds (e.g. in place of first spray of
Metalaxyl/Curzate)
How long does Tiger continue to protect after it is applied ?
The duration of effectiveness depends on weather conditions prevailing but
when used with contact fungicides, Tiger actively protects up to 10 days under
moderate disease conditions, or 5 - 7 days under severe conditions. Use of
Tiger at recommended doses and through coverage is important for superior
control of Late Blight on Potato.
Can Tiger also contain all other diseases of Potato ?
No. Tiger works only on Late Blight.
FAQs
55. Does Tiger exhibit curative action ?
Tiger has a special advantage of being a strong anti sporulant,
which arrests the spread of disease after infection.
However, As you are aware, right timing of application is the first
defense against Late Blight an hence Tiger should be applied either
preventive or as early curative i.e in initial stages of infection.
Can Tiger also protect newly emerging foliages ?
Yes. Tiger enters inside the plant by diffusion process and
protects the new foliage emerging soon after application. How
ever, under the disease favoring weather conditions and high
disease pressure the potato crop requires frequent rounds of
Tiger sprays at shorter intervals.
FAQs
56. Is Tiger superior than existing systemic fungicides used in the
control of Late Blight in Potato ?
In the management of Late Blight, it is important to rotate chemicals with
different modes of action thereby not allowing the disease to become “ resistant”
to a frequently used product / mode of action.
The Indian potato grower, after a long wait, is finally getting a better choice in the
form of Tiger .
a) because it contains a totally new active ie Tiger , and
b) It’s mode of killing the pathogen is unique (cell wall Lysis) and “ different” from
existing systemic fungicides.
The combined impact of both above points is a brand new tool for effectively
controlling lateblight.
Can it be mixed with any other fungicide or insecticide
commonly used in Potato ?
Tiger is compatible with commonly used contact fungicides like Metiram,
Mancozeb and COC. Likewise, it can be mixed with commonly used
insecticides. It is always prudent to do a small test by mixing the 2 different
chemicals to check for compatibility prior to spraying
FAQs
57. What is MRL (ppm) and PHI ( days ) ?
PHI-16 Days (P),26 Days(G) MRL-0.5 ppm
HI
LO
Desirable to grower
Not desirable
LO
HI
MRL
PHI MRL
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