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Tikka disease of Groundnut
ANJALI
MSC Microbiology 3rd sem
SGRRU

Content
 Introduction
 Causal Organism
 Symptoms
 Disease Cycle
 Favourable Condition
 Disease Management
 Conclusion
 Reference

Introduction
 Groundnut is the most important oilseed crop of india
 The total area under ground nut is about 8 million hectares
 Tikka disease is the major disease of groundnut In india
 It occurs in every state in India and in every ground of nutgrowing countries of the
world
 In Uttar Pradesh , the disease locally known as chitwa or haldai

Causal organism
 The causal organism of this disease are Cercospora personata and Cercospora
arachidicola
 The symptom caused by the two pathogen will differ
 This disease also called Leaf spot of Ground nut because it causes Leaf spot on the
leaves

Symptoms
 Symptoms appear when the plants are 1 or 2 months old
 Due to excessively spotting on the leaves , there is gradual weakening of the
foliage which results in defoliation
 Consequently , fewer and smaller nurs are formed
 According to sundarram (1965) severe intensity of infection leads upto 22%
reduction in yield

Symptoms
 C.arachidicola causes early spot and C.personata causes late spot
 First symptom of both leaf spots is the appearance of pale areas on the upper
surface of older leaves
 As the lesion develops the two species can ve distinguished

Early leaf spot symptoms
 Sub circular dark brown spots are produced on the upper leaflet surface
 Spots are of lighter shade of brown on the lower side of leaflets
 Yellow halo is seen around the brown spots

Late leaf spot symptoms
 Late leaf spots are nearly circular and darker than early leaf spots
 Yellow halo develops around each only in later stage of development
 Late leaf spots can be distinguished from those of early leaf spots
 Late Leaf spots are darker with no or light yellow halo

Causal organism
 The mycelium of C.arachidicola is inter and intracellular,brown, septate and without
haustoria.
 Conidiophores are yellow brown and as the conidium remains attached to
geniculation oj conidiophore.
 Conidiophore are 22-44 micron long and 3-5 microm broaf continuous or 1-2
septate.

Causal organism
 Cercospora personata produces an intercellular branched mycelium
 To absorb food from the host tissue, haustoria are developed.
 Lesions appear 2-4 weeks later.
 Conidiophore of C.personata are 25-54 micron long,5-8 mircon Broad continuous
or 1-2 septate.
 Conidia are terminal and each conidiophore bear each single conidium at the apex.
 It is potentially more damaging because it produces more spots, spreads faster and
causes earlier defoliation.

Dieseade cycle
 Perennation
 The disease perpertuates through conidia lying in the soul on diseased plant debris
and through conidia being carried in thr shell of groundnut.
 Primary Infection
 When the new crop of Groundnut starts growing,the viable conidia are brought to
the host surface by various agencies, germinate in favourable conditions and cause
primary Infection.
 Secondary infection
 The secondary infection on healthy plants in the same field or adjacent fields is
brought by conidia produced on primary infected leaves.

Cont.....
 The conidia are dispersed by air or other agencies , which bring them on the
healthy leaves
 Later , they germinate in favourable conditions and causes infection

Favourable factors
 Relative humidity is the most important factor for infection
 A period of three days of high humidity is essential for maximum infection
 Prolonged low temperature and dew also favour Severe infection

Unfavorable condition
 Application of potash slightly decrease disease incidence
 Leaf spot development is minimal when gypsum is applied as a source of calcium

Disease management
 As the disease is soil borne, proper crop rotation is needed
 Plant disease debris should be burnt to avoid soil infection
 Early planting, alteration in date of sowing and use of maturing varieties helps to
escape room the attack of disease
 Foliage spray with Bordeaux mixture , Dithane M-45(.2%), Benlate and Bavistin (0.1)
give good result

Conclusion
 Tikka disease is the common disease in ground nut caused by Cercospora
arachidicola and Cercospora personata
 In the diseased condition , many circular spots appear on the surface of leaf
 Conidia of the fungus present in soil or those present in the fruit shell is the source
of infection
 Use of fungicides controls the disease

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