L 10 Non-sys. fungicides.pptjogggffrrddddd

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1. Groups of Fungicides -
Mercury, Copper, Sulphur
Heterocyclic nitrogen compounds,
Quinones and
Miscellaneous fungicides

2. I. Mercury fungicides
Used for treating seeds, rhizomes, corns, bulbs, etc.,
It has both fungicidal and bactericidal properties.
Extremely toxic in Nature.
Highly toxic to animals & human (persistence in food chain)
Sometimes phytotoxic
1. Inorganic
e.g. Mercuric chloride, Mercurouschloride
Burns (1914) –steeping of potato tubers for surface sterilization of
diseased plant materials to control R. solaniused

3. 2. Organic
MethoxyEthyl Mercuric chloride (MEMC) –
Agallol, Areton, Emisan, Wet Cerasan
Phenyl Mercury Acetate –Dry Cerasan
TolylMercury Acetate –AgrosanGN
Dosage
Dry seed treatment –0.25% (1% a.i.)
Wet seed treatment –0.2 –0.5 % (2.5 –6.0% a.i.)
Mechanism of action
Affects enzyme synthesis.
Organic forms are more toxic than inorganic (lipid soluble & highly
volatile) which easily pass into spore through membrane)

4. II. Copper fungicides
Prevost (1807) demonstrated efficacy of CuSO
4against wheat bunt
Toxic to bacteria also
Recommended along with antibiotics.
All Copper fungicides are inorganic compounds.
1. Bordeaux mixture
Prof. P. M. A. Millardet(1882) –downy mildew of grapevine
Used to control of downy mildew of grapevine, late blight of potato,
Kolerogaof arecanut, foliar diseases like anthracnose, leaf spots,
leaf blights, etc.
Also effective against some bacterial diseases (citrus canker).
Used as soil drenching to control nursery diseases like damping off
caused by Pythiumsp, Phytophthorasp., Rhizoctoniasp, and
Phytophthorawilt of betelvineand basal stem rot of coconut.
To control of coffee rust, Bordeaux mixture is used at 0.5% only

5. Method of Bordeaux mixture 1%
It is prepared with the following materials in the ratio of 1:1:100.
Copper sulphate(CuSO
4)- 1 kg
Quick Lime [Ca (OH)
2] - 1 kg
Water - 100 lit
Non-metallic vessels (earthen / cement / porcelain/ plastic vessel)
are used to prepare Bordeaux mixture.
One kg CuSO
4 of is taken, powdered and dissolved in 50 l. of water
One kg of good quality quick lime is taken and dissolved in another
50 lit of water in a separate vessel. Strain the lime solution to
remove stones and other undissolvedmaterials.
Then the copper sulphatesolution is slowly added to lime solution
with constant stirring of the mixture.

6. There is also another method, where simultaneous addition of the
above two solutions is made in a third container and mixed well.
The addition of lime is made to neutralize the copper sulphate
solution which is acidic in nature.
Copper sulphatesolution when sprayed without neutralizing the pH
will cause phytotoxicsymptoms on the plants. The resultant solution
(Bordeaux mixture) should be neutral and sky blue in colour.
If the mixture is acidic, it shows the existence or free copper in the
solution. Hence, it is essential to test the presence of free copper
before the Bordeaux mixture is used on the crops.

7. Chemistry of Bordeaux mixture
The chemistry or Bordeaux mixture is complex:
CuSO
4+Ca (OH)
2----------> Cu (OH)
2+ CaSO
4
It is a gelatinous precipitate of copper hydroxide and calcium
sulphate. Cupric hydroxide is the active principle, toxic to the fungi
Three important theories to explain the action of Bordeaux mixture
CuOHis brought into solution by atmospheric agencies more by
CO
2present in air.
Leaves on which Bordeaux mixture sprayed exert some chemical
action on the Bordeaux mixture and thus make CuOHsuitable.
Bordeaux mixture itself is inert till the fungus falls on it and soon
after the fungus comes in contact, it produces some chemical
which makes CuOHsoluble and copper enters the germ tube and
kills the fungi

8. Methods of testing neutrality
a. Field test: Polished Iron knife or sickle is immersed in the
prepared Bordeaux mixture for minutes. If reddish deposit is noticed
on the polished surface of the knife/sickle it means that the mixture
is in acidic pH.It indicates that the mixture has to be neutralized b
addition of lime. In such condition add lime solution and test for
neutrality by following the method.
b. Laboratory tests
Litmus paper: In the prepared Bordeaux mixture, dip a bit of blue
litmus paper. Blue colourshould not change, if it is neutral.
pH paper: Dip a bit of the wide range pH paper and watch for the
colourto the neutral pH in the paper.
Chemical test: Take 5 ml of 10% potassium ferrocyanidein a test
tube; add few drops of the prepared Bordeaux mixture to the above
solution. If red precipitate is seen it shows that the prepared mixture
is acidic. When the mixture is acidic add sufficient lime solution.

9. Precautions
•Good quality lime and copper sulphateshould be used.
•Metallic vessels should not be used for its preparation.
•Always copper sulphatesolution should be added to lime
solution. If lime solution is added to copper sulphate
solution there will be precipitate of free copper and the
resultant mixture will be least toxic.
•Bordeaux mixture should be prepared afresh every time and
sprayed immediately after preparation. To keep it
overnight add jaggeryat 1g/lit.
•Some adhesives like casein, resin, Teepol, Triton-AE and
vegetable oils can be added in regions of heavy rainfall.

10. Merits
•It can be prepared with locally available materials. It is an effective
fungicide and highly adhesive.
•Relatively cheaper fungicide.
•It has got good tenacity.
•It is non-poisonous and safe to handle. It is not phytotoxicto many plants.
•It controls both foliar diseases and soil borne diseases.
•As it contains copper it cures copper deficiency in plants.
•It has phytotoniceffect and prevents defoliation.
Demerits
•The process or preparation is laborious and cumber some.
•It has low keeping quality.
•It is phytotoxicto apple, plums, peaches, pear, rose, sorghum, rice
varieties like IR-8 and maize variety like Gangahybrid
•It leaves blemishes on the leaves after its spray which is unsightly in
appearance in ornamental plants.
•It is corrosive to iron and zinc.
•Since the coating of Bordeaux mixture on the leaf persists for sometimes
temporary retardation of photosynthesis has been reported.

11. 2. Bordeaux Paste10 % solution of Bordeaux mixture
Used to swab the wounded portions in stem bleeding of coconut
(Ceratocystisparadoxa), die-back and gummosis of citrus (Colletotrichum
gloeosporioides) and Dendrophthoeaffected mango and citrus trees.
Bordeaux paste is prepared with the same materials as in
Bordeaux mixture but here the ratio is 1:1:10.
Copper sulphate - 1 kg
Quick lime - 1 kg
Water - 10 lit
3. Burgundy mixture (Mason, 1887)
Alternative to Bordeaux mixture but less effective
CuSO
4+ Na
2CO
3+ water i.e., 1.8 kg: 1.8 kg: 225 lit.
The procedure for preparation of Burgundy mixture is same as that
of Bordeaux mixture
4. Cheshuntcompound (Bewley, 1921)
2 parts of CuSO
4+ 11 parts of (NH
4)
2CO
3
Dry powder used for soil drenching and spray.

12. 5. Chaubattiapaste
Wound dressing fungicide against stem diseases of apple,
peach, pear, plum, apricot, etc.
800 gm of Copper carbonate + 800 gm Red lead + 1 lit of raw
linseed oil or lanolin
6. Copper oxide
Seed and foliage protectant.
Available as Cuprocide, Perenox, Fungimar, Fungicopper.
7. Copper carbonate
Seed dresser –available as Cubredon45 % Cu
8. Copper hydroxide
Effective for the management of Citrus canker, bacterial
leaf blight, bacterial leaf streak, false smut, (fungicide &
bactericide); Available as Kocide.

13. 9. Copper oxychlorideor Fixed copper [(Cu
2Cl (OH)
3]
It contains 4-50% metallic copper.
Copper is fixed –less soluble in nature and less phytotoxic.
Foliage and soil fungicide (Damping off & leaf blight)
Dusts (Blimix4%)
Wettablepowder (Fytolan, Blitox, Blue copper, Fyromix)
Mode of action
General distribution of fungal cell metabolism and
breakdown of cell integrity.
It affects protein and enzyme synthesis.
Phytotoxicity
Bordeaux mixture causes russettingin apple
COC –phytotoxicto IR 8 rice, maize hybrid (Ganga)
Cu fungicides (0.2%) –toxic to rapeseed and mustard.

14. Sulphurfugicides
___________________________________
Inorganic Organic (Dithiocarbamates)
Elemental sulphur Lime sulphur Dialkyl Monoalkyl
Dust Wettablepowder Thiram Nabam
Ziram Zineb
Ferbam Maneb
Mancozeb
Vapam

15. III. Sulphurfugicides
Inorganic
Elemental sulphur(Fine grinding of mineral) e.g. Dust, WP
Dust -Efficacy increases with fineness of particles (47-75 µm)
WP-Sulphuris grinded with colloidal material
(casein, bentoniteclay)
Lime sulphur
Prepared by boiling lime + sulphur(10 kg of lime + 7 kg of sulphur
+ 250 lit of water –1 h heating). The resultant golden coloured
liquid (calcium polysulphide) is used.
It is more phytotoxicthan elemental sulphurbecause of greater
water solubility.

16. Mechanism of action (Elemental sulphur) –Marsh, 1929
Oxidisedsulphurtheory: Elemental sulphuroxidized to SO
2, which
is fungicidal in action.
H
2S theory: Elemental sulphuris reduced to H
2S, which is toxic to
fungal spores.
Direct action theory: It affects metabolic process and disturbs
hydrogenation and dehydrogenactionof fungal cell. It emits
vapour, which prevent germination and growth of fungal spores.
It inhibits respiration. Disrupts protein and chelateswith heavy
metals within fungal cell.
Phytotoxicity
Burning of foliage in cucurbits against powdery mildew
In apple fruit it causes sulphursun scald
It inhibits pollen germination and fruit set in apple.

17. Organic (Dithiocarbamates)
Tisdale (1931) –found fungicidal nature of dithiocarbamicacid.
Unstable in free state. When reacts with other metals / acid it is
highly fungitoxicand stable.
Diakyldithiocarbamate-E.g., Thiram, Ziram, Ferbam
Monoalkyldithiocarbamate–E.g., Nabam, Zineb, Maneb,
Mancozeb, Vapam
H S
N-C-S-H Dithiocarbamicacid (NH
2COOH –carbamicacid)
H
Diakyldithiocarbomates
R S
N -C -S -Na
R

18. a. Thiram(TMTD) –Tetra methyl thiurumdisulphide
First dithiocarbomateused. Available in WP, Dust.
It has antibacterialproperty also. White powder.
H
3C S S CH
3
N -C -S –S –C -N
H
3C CH
3
Trade Name: Arasan, Thiram, Thiride, Tersan, Hexathin, Thylate,
Fermide, Arasan(SF) –Slurry form.
Dose:Seed –2-4 g / kg (treated seeds repel rodents)
Spray –0.2 %
Soil –15 –25 kg/ha

19. b. Ziram(Zinc dimethyldithiocarbomate) –white powder
H
3C S S CH
3
N -C -S –Zn –S -C –N
H
3C CH
3
Trade Name:Cuman, Hexazin, Ziram, Zerlate
c. Ferbam (Ferric dimethyldithiocarbomate) –Black powder
H
3C S S CH
3
N -C -S –Fe –S -C -N
H
3C S CH
3
C = S
N
H
3C CH
3
Trade name:Coromet, Ferbam, Ferberk, Fermate, Fermocide
Mechanism of action
Strong chelating agent of metals, that are needed for the fungal cell.
Free radicals are toxic –interferes with enzyme activity

20. ii. Monoalkyldithiocarbamates
a. Nabam(Disodium ethylene bisdithiocarbomate)
First in this group. Unstable and water soluble –hence
phytotoxic. Used for soil drenching.
R S
N -C -S –Na Monoalkali
H
H S
H
2C -N -C -S -Na
H
2C -N -C -S –Na
H S (Nabam)
Trade Name:Chembam, DithaneD-14, DithaneA-40, Parzateliquid.

21. b. Zineb(Zinc Ethylene bisdithiocarbomate)
It provides Zinc (good for paddy, tomato). Compatible with all except
with lime. Phytotoxicto Zinc sensitive plants (Grapevine).
S (Trade Name:DithaneZ-78, Hexathane, Parzate)
H
2C -NH -C –S
Zn
H
2C -NH -C -S
S
c. Maneb (Manganese ethylene bis dithiocarbomate)
H S (Trade Name:DithaneM-22, Manzate)
H
2C -N -C –S
Mn
H
2C -N -C -S
H S
d. Mancozeb
Zinc (2%) + Maneb(78%) –DithaneM 45, IndofilM 45, Manzeb

22. e. Vapam(sodium methyl dithiocarbamate–SMDC) (Liquid)
H
3C -N -C -S -Na
H S
Fugicidal, nematicidaland herbicidal properties.
Sometimes insecticidal also.
When applied in soil it releases fumigant called methyl
isothiocyanate(H
3C-N=C=S).
Dose:Soil –1.5 –2.5 lit / 10Sq.m
Mechanism of action (Monoalkyl):
Free H at the N –split of H
2S –formation of isothiocyanategroup,
which show fungicidal activities.
In general it releases thiocarbaryl(-N=C=S) which inactivates SH
group of enzymes.
Dithiocarbamatesare inactive against powdery mildew (Erysiphales)

23. IV. Quinonefungicides
Highly toxic –excellent seed dresser –naturally present in
plants and animals, produced by oxidation of phenolics.
Not recommended for spraying, since it is degraded by sunlight.
i. Chloranil:Spergon(2,3,5,6 –tetrachloro1,4-benzoquinone)
Stable in acidic and unstable in alkaline pH.Decomposed in moisture
and light and gives chlorogenicacid.
Effective against ext. seed –borne diseases. Dose:2–4 g / kg of
seed.
ii. Dichlone:Phygon(2,3,-dichloro –1,4-Naphthoquinone)
Mechanism of action
Binding of quinonenuclear to SH, NH
2group in the fungal cell.
Disturbance in the electron transport system.
Cl
O
Cl
Cl Cl
OH
Chloranil
Cl
Cl
O
O
Dichlone

24. V. HeterocyclicnitrogenCompounds
Phthalamides–Captan, Captafol, Folpet.
Dicarboximides-Iprodione, Vinclozolin.
Captan(Kittleson, 1952) –Kittleson’skiller
Effective seed dresser against Pythium
Also used for soil drenching and foliar spray
Unstable at alkaline pH
Degrades slowly in sunlight when sprayed
Trade Name:Captan, 50WP, 75WP, Hexacap
Mode of action:S or Clis toxic in nature. Formation of H
2S, which
is lethal. It inhibits enzymes synthesis.
Captafol:It is meant for foliar spray.
Trade Name: Captaspor, Difolatan, foltaf
Folpet: Closely related to captanand sold as Phaltan, orthophaltan.
Effective against powdery mildews, rusts in addition to diseases
controlled by captan

25. Cl
3
C
CSN
C
O
O
Captan
(N-trichloromethyl-thio-4-cyclohexene –1,2 –
dicarboximide)
H
C
CSN
C
O
O
Cl
Cl
Captafol
(cis-N-(1, 1, 2, 2–tetrachloro ethyl thio) -4-
cyclohexene –1, 2 dicarboximide)
Cl
3
C
CSN
C
O
O
Folpet
It is an analogue of captanit has the constitution
of N –(trichloromethylthio) phthalimide.

26. Dicarboximides
Iprodione
Broad spectrum contact fungicide
Used as foliar spray, seed treatment and post-harvest dip.
Trade Name: Roveral, Glycophene
Vinclozolin
Effective against sclerotiaproducing fungi
Trade Name: Ornalin, Ronilan, VorlanVinclozolin
Act as antisporulantagainst Moniliniafructicola

27. VI. Aromatic compounds (Benzene fungicides)
Dinocap: Karathane, Arathane, Mildex, Crotothane
Good acaricideand mildewcide(Eradicantaction)
Substitute for sulphursensitive crops (cucurbits, apple varieties)
Spray (0.05-0.1%)
PentaChloroNitro Benzene (PCNB):Brassicol, Quintozene, PCNB
It prevents sporulation(antisporulant) and inhibits growth of soil fungi
(fungistatic); Nematicidalproperty
It is a good substitute for organomercurials.
Effective against club root, rots and not against Fusarium
Mode of action
Antimitotic–inhibits cell division and growth
Disrupts semi permeability of cell membrane and causes lysisof cell.

28. Dichloran/ DCNA (Dichloronitroaniline): Bortran, DCNA, Allisan
Effective against sclerotiaproducing fungi
Used as foliar spray and post harvest dip
Mode of action: Inhibition of protein synthesis.
Diazoben/ Fenaminosulf:Dexon
Effective against Damping off and root rot (Pythium, Phytophthora)
Seed and soil application,
Photolabile–hence not recommended for foliar spray.
Carcinogenic in action.
Mode of action: It inhibits respiration

29. Chlorothalonil: Bravo, Daconil, Kavach, Safeguard
Broad spectrum, multisite action fungicide.
Effective against leaf spots and blight.
Alternative to mancozeb
Mechanism:React with thiolgroup of enzymes
Biphenyl(Diphenyl)
Effective against post harvest rots in citrus.
Volatile in action –dipping or wrapping of fruits with
fungicide impregnated paper.

30. NO
2
Cl
Cl
ClCl
Cl
C
6H
13
NO
2
CH
O
O
2N
O C -CH = Ch –CH
3
CH
3
NH
2
ClCl
NO
2
Dinocap
It is a mixture of 2, 4-dinitro–6-octyl
phenyl crotonateand 2, 6-dinitro-4-
octyphenyl crotonate
PCNB
Pentachloronitrobenzeneor Quintozene
Dichloranor DCNA
(Dichloro nitroaniline)
(2, 6-dichloro-4, nitroaniline)

31. Cl
C N
Cl
Cl -C N
Cl
H
3C -N –CH
3
N = N –SO
3Na
Diazoben/ Fenaminosulf
(Sodium p-dimethylamino benzene
–diazosulphonate)
Chlorothalonil
(2,4,5,6-tetrachloro-isophthalonitrile)
Biphenyl or Diphenyl

32. VII. Organotincompounds (Antibacterial also)
TPTH/ Fentinhydroxide (Triphenyltin hydroxide):Du-Ter,
It is more safe than other organotincomps.
TPTA/ Fentinacetate (Triphenyltin acetate):Brestan
Compatible with lime sulphur& B.M and forms TPTH
It inhibits spore germination and kills germinated spores.
TPTC/ Fentinchloride (Triphenyltin chloride):Brestanol
VIII. Organophosphorous compound
Edifenphos(O-ethyl –S, S-diphenyldithiophosphate):Hinosan
Specific to Blast and Brown leaf spot.
Also controls sheath blight and sheath rot.
Mechanism: It inhibits chitin synthesis

33. Sn -OH
Sn –O –C –CH
3
O
Sn -Cl
E
5C
2–O –P –S
O
S
TPTH / Fentinhydroxide
(Triphenyltin hydroxide)
TPTA / Fentinacetate
(Triphenyltin acetate)
TPTC / Fentinchloride
(Triphenyltin chloride)
Edifenphos
(O-ethyl –S, S-diphenyl
dithiophosphate)

34. IX. Imidazolecompound
Prochloroz(Octave, Sportak)
Effective against ascomycetesand Deuteromycetes
Controls post harvest diseases of fruits and vegetables
Sterol biosynthesis inhibiting fungicides.
X. Nickel compounds
Nickel chloride (used at 170 g/67 of water) is effective in the control
of tea blister-blight. Nickel sulphateor nickel chloride as foliar spray
(0.3%) induced resistance against BLB disease of rice
XI. Miscellaneous compounds
Dodine(Cyperex): Excellent fungicide for apple scab
Glyodin(Glioxalidine, Glyodin): Fungistaticin action
Chinomethionate(Morestan25% WP)
Excellent protectantand eradicantof powdery mildew of fruits,
cucurbits and ornamentals.
More effective than Karathaneagainst powdery mildews and mites
Binapacryl: Effective against rice BLB and tea blister blight

35. Mineral oils
Light viscosity oils atomized into very fine droplets (50-100 µm in
dia) which provide very good control of Banana sigatokaleaf spot.
Fungistaticin action –Physically restricts the growth of the fungus
by obstructing gas exchange and by blocking stomatalopening.
High sugar pathogens (powdery mildew & rusts) are susceptible
to mineral oils

36. Thank you