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Tikka disease of groundnut

It explains in detail about the tikka disease of groundnut. Causal agent, mesures to control it is also mentioned.

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Tikka disease of groundnut

  1. 1. Tikka Disease of Groundnut Keshav Narayan Pai Msc I DOS in Botany
  2. 2. Content • Introduction • Causal Organism • Symptoms • Disease Cycle. • Favourable Condition. • Disease Management • Conclusion • Reference
  3. 3. 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 is locally known as chitwa or haldai.
  4. 4. Causal organism • The causal organism for the tikka disease of ground nut are Cercospora personata and Cercospora arachidicola. • The Symptoms caused by the two pathogens will differ. • This disease is also called Leaf spot of Ground nut because it causes leaf spots on the leaves.
  5. 5. • Symptoms appear when the plants are 1or 2 months old. • Due to excessive spotting on the leaves, there is gradual weakening of the foliage which results in defoliation. • Consequently, fewer and smaller nuts are formed . • According to Sundarram(1965) severe intensity of infection leads upto 22%reduction in yield.
  6. 6. Symptoms  According to Woodruff(1933) designated the disease caused by C.arachidicola as early spot and that caused by C.personata as late spot.  The first symptom of both the leaf spots is the appearance of pale areas on the upper surface of older leaves.  As the lesions develop the two species can be distinguished.
  7. 7. Early Leaf Spot Symptoms • Sub-circular dark brown spots are produced on the upper leaflet surface. • The spots are of lighter shade of brown on the lower side of the leaflets. • Yellow halo is seen around the brown spots.
  8. 8. spot on stem
  9. 9. Infected leaf
  10. 10.  Lateleafspotsarenearlycircularanddarkerthanearlyleaf spots.Yellowhalodevelopsaroundeachonlyinlaterstageof development.  Lateleafspotscanbedistinguishedfromthoseofearlyleaf spots.Lateleafspotsaredarkerwithnoorlightyellowhalo. Late leaf spot
  11. 11. • The mycelium of C.arachidicola is inter and intracellular, brown,septate and without haustoria. • Conidophores are yellowish brown and as the conidium remains attached to geniculation on conidiophore. • Conidiophores are 22-44 micron long and 3-5 micron broad continuous or 1-2 septate.
  12. 12.  Cercospora personata produces an intercellular branched mycelium.  To absorb food from the host tissue, haustoria are developed.  Lesions appears 2-4 weeks later.  Conidiophores of C. personata are 25-54 micron long, 5-8 micron broad continuous or 1-2 septate.  Conidia are terminal and each conidiophores bear each single conidium at the apex.  It is potentially more damaging because it produces more spots, spreads faster and causes earlier defoliation
  13. 13. Perennation  Thediseaseperpetuatesthroughconidialyinginthesoilon diseasedplantdebrisandthroughconidiabeing carriedinthe shellofgroundnut. PrimaryInfection  Whenthenewcropofgroundnutstartsgrowing,theviable conidiaarebroughttothehostsurfacebyvariousagencies, germinateinfavourableconditionsandcauseprimaryinfection.
  14. 14. Cont..... Secondary infection  The secondary infection on healthy plants in the same field or adjacent fields is brought by conidia produced on primary infected leaves.  The conidia are dispersed by air or other agencies , which bring them on the healthy leaves.  Later they germinate in favourable conditions and cause infection.
  15. 15. • 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.
  16. 16. • The application of potash slightly decreases disease incidence. • Leaf spot development is minimal when gypsum is applied as a source of calcium.
  17. 17. • As the disease is soil-borne, proper crop rotation is important. • Plant disease debris should be burnt to avoid soil borneinoculum. • Early planting,alternation in date of sowing and use of maturing varities helps to escape rom the attack of the disease. • Growing moderately resistant cultivars like ICGV 89104, ICGV 91114 (EM), ICGV 920920, ICGV 92093 (MM). • Foliage spray with Bordeaux Mixture (4:4:50),Dithane M-45 (0.2%), Benlate and Bavistin (0.1%) gives good results.
  18. 18. Disease Management • Cultural Method 1.Grow tolerant varieties can be grown wherever early leaf spot is severe. 2.Intercropping pearl millet or sorghum with groundnut (1 : 3) is useful in reducing the intensity of early leaf spot. 3.Crop rotation with non-host crops preferably cereals. • Mechanical Method 1.Deep burying of crop residues in the soil, and removal of volunteer groundnut plants are important measures to reduce the primary source of infection
  19. 19. Cont..  Biological Method Foliar application of aqueous neem leaf extract (2-5%) or 5% neem seed kernel extract at 2 weeks interval 3 times starting from 4 weeks after planting is good.  Chemical Method Spray carbendazim 0.1% or mancozeb 0.2% or chlorothalonil 0.2%.
  20. 20. Conclusion • Tikka Disease is a common disease in ground nut caused by Cercospora arachidicola and Cercospora personata. • In the diseased condition, many circulars spots appear on the surface of the leaf . • The 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.
  21. 21.  Mehrotra.R.S.(1980).PlantPathology.TataMc.GrawHillPub.CO.Ltd. Pg.no-455-465.  Rangaswamy,GandMahadevan,A(2002).Diseasesofcropplantsin India,PrenticeHallofindia,Pvt.Ltd.Pg.no-334-343.  www.flickr.pathology.Tikkadisease.Com
  22. 22. Than k You