TIKKA DISEASE OF GROUNDNUT.pdf

Tikka disease is a major fungal disease of groundnut caused by two species of Cercospora belongs to deuteromycetes , Cercospora arachidicola and C. personatum

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Leaf spot or Tikka disease
of Groundnut
Smt.Shubhangi Patil,
Department of Botany, Miraj Mahavidyalaya, Miraj
Mobile no.:8999578863
EMAIL ID: [email protected]

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Distribution
▪Tikkadiseaseisthemostprevalentanddestructive
diseaseofgroundnutsallovertheworld.Itinfects
groundnutinalltheareaswherethecropisgrown.
▪Tikkadiseaseofgroundnutcausesupto50%loss
globally(Tshilenge-Lukandaetal.,2012)andup
to70%loss(Mushrifetal.,2017)intheIndian
subcontinent.Thediseaseisfavoredbyhotand
wetconditions.

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Host: Groundnut (Arachis hypogaea L.)
Pathogens: Cercospora arachidicola Hor and
Cercosporidium personatum (Berk & Curt.) Deighton

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Symptomsappearintwostages;anearlyleafspotcausedby
Cercosporaarachidicolawhile,lateleafspotcausedby
Cercosporidiumpersonatum.Earlyleafspotbeginstodeveloponthe
uppersurfaceoflowerleaves.Thesearebrowntoreddishbrownin
coloralwayssurroundedbyyellowhalo.Initially,thespotsare
circularbut,latermorethanonespotcoalesceandbecomeirregular.
Earlyleafspotsareraisedontheuppersurface,whilesmoothatlower.
Lateleafspotsappearlateintheseason.Thesearedarkbrownto
blackcoloredandusuallydonothaveyellowhalo.Incontrasttothe
earlyspot,mostofthespores/conidiaarebornatthelowersurface,
givingaraisedappearance,whiletheuppersurfaceisnearlysmooth.
Symptoms

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Causal Organism
Early leaf spot is caused by Cercospora arachidicola while
late leaf spot is caused by Cercosporidium personatum
(Syn. Cercospora personata).
Conidiophores of Cercospora
Section of groundnut leaves passing through the
spots. a: host tissues, b: fungal stroma arising
from stomatal chamber, c: conidiphoreswith
knee-shaped bending, d: conidia

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❖Cercospora arachidicola cause
early leaf spot infection, which
includes symptoms like brown-
colouredround or oval spots.
Yellow halo also appears
around the spots in an irregular
fashion.
❖Cercospora personata cause
late leaf spot infection, which
includes symptoms like the
appearance of the large and
dark black-colouredspots on
the leaves, stems, seeds and
shells of the groundnut.

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A: infected leaf showing
characteristic spot.
B: spots surrounded by halo,
C: geniculate mycelium.
D: V.S. of spot showing
conidiophore and conidia.
E: apices of conidiophores
showing knee-shaped
bending.
F: conidia

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Disease Cycle of Tikka Disease
The disease cycle of tikka disease of groundnut is carried out by the
fungal spores of the Cercosporaspecies, i.e. Cercospora arachidicola
and Cercospora personata.

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Control measures
❖Management of early tikka disease of groundnut:
•Crop rotation
•Eradication of infected plants by burning or burying them in deep pits.
•Pruning can also be done with the help of pruning scissors by removing
the infected parts of the plant.
•The seeds of groundnut that are within the shells can be disinfected with
sulphuric acid, and those are without the shell can be treated for half an
hour with 0.5% of copper sulphate solution.
•Raw seeds after dressing with Agrosan GN can also reduce the chances of
infection.
❖Management of late tikka disease of groundnut:
The late infections of tikka disease can be only managed by the use of
effective fungicides like Bordeaux mixture as a spray.

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