Diseases of Black pepper

Details about major diseases of black pepper

1. COLLEGE OF AGRICULTURAL TECHNOLOGY (Affiliated to Tamil Nadu Agricultural University, Coimbatore-3) Kullapuram (Po), Via Vaigai Dam, Theni-625 562 DISEASES OF BLACK PEPPER Student: Course Teacher: Sruthi A B Dr. Parthasarathy S 2015021126 Asst. Prof. Plant Pathology.

2. List of diseases in black pepper 1. Foot rot /quick wilt disease 2. Pollu disease /anthracnose 3. Slow decline /slow wilt 4. Stunt disease 5. Phyllody disease 6. Basal wilt 7. Leaf rot and blight

3. 1. Foot rot / Quick wilt of pepper Significance: Quick wilt is one of the most destructive diseases of pepper prevalent in Kerala. The infection initiates with the onset of south-west monsoon. Affects all cultivable varieties and vines of all age group.

4. SYMPTOMS Collar: Formation of water soaked lesions, changing to wet slimy dark patches on the collar region and rotting. Foot rot, the fatal symptom, is seen at the collar region resulting in quick wilt. Roots: Root infection also initiates as water soaked dark patches on feeder, tertiary, secondary and primary roots resulting in root decaying and shredding of roots.

5. Stem: The infection on runner shoots and cuttings cause rotting of sprouts resulting in shoot rot. breaking of stem at the nodal regions branches turn dark brown due to rotting Leaves: Uniformly dark on young leaves or shows concentric zonation with grayish centre on mature leaves. Water soaked lesions and rapidly expands into large dark brown spots.

6. Spikes and Berries: withering and shriveling of berries and heavy spike shedding without any discoloration.

7. @ vikaspedia.in /agriculture

8. @ cpsskerala.in

9. Pathogen: Causal organism: Phytophthora capsici Leonian It i s a heterothallic   oomycete Phytophthora capsici  produces both a male and a female type  gametangia  called an  antheridium  (male) and an  oogonium  (female). The oospores, zoospore and chlamydospores surviving in soil germinate with the receipt of monsoon showers and initiate infection in roots and at collar region .

10. Systematic position: Phylum: Heterokontophyta Class: Oomycota Order: Peronosporales Family: Peronosporaceae Genus: Phytophthora Species : P. capsici

11. Sporangia Disease cycle www.wikipedia.org

12. Favourable condition: Heavy rainfall, more number of rainy days, high relative humidity of more than 90%, low temperature of 22-25 ºC and less sunshine hours are the favorable climatic conditions for the disease

13. Mode of spread: Primary spread: oospores Secondary spread: zoospores Secondary inoculum , Zoospore leads to sudden outbreak. Spread is through soil, water, root contacts, movement of people, slugs, snails, use of contaminated implements etc. Intercultural operations especially soil digging around the vine, nematode infestation, root mealy bug attack etc. predispose the infection.

14. Management: Phytosanitation . Drench such spots with 0.2% COC (2g/L) or 1% Bordeaux mixture to eradicate the inoculum from the soil. Plant disease free rooted cuttings. Allow penetration of sunlight. Proper pruning. Use biocontrol agents such as Trichoderma viride ,  Pseudomonas fluorescens and VAM inoculated cuttings

15. During the initial phase of infection, drench the vines with 0.2 % Potassium/Sodium Phosphonate . Spray with 0.1 to 0.15% Potassium/ Sodium Phosphonate which is compatible with biocontrol agents. Do not use copper fungicides if the garden is protected with biocontrol agents. Spray Ridomil MZ ( Metalaxyl + Mancozeb ) @ 2g / L.

16. 2. POLLU DISEASE / ANTHRACNOSE @ agritech.tnau.ac.in

17. Other names: In India, this is known as fungal ‘ pollu ’ disease. In Malaysia/Indonesia : black berry disease. Also referred to as "Berry spot" and "Berry split”.

18. Symptoms: Symptoms appear in leaves and stems. Circular or irregular grey spots appear in the leaves. The lesion or spot has a prominent yellow halo around it. These lesions may coalesce resulting in leaf blight and subsequent defoliation. @www.kisansuvidha.com @ agritech.tnau.ac.in

19. Concentric rings of acervuli appear on upper surface of the leaves. On the stem the infection appear at the tips spreads downwards and kill the entire vine. @www.kisansuvidha.com

20. On spikes, black discoloration appears on the attached portion of the stem, later leading to spike shedding which results in 100% yield loss. On the berries, sunken areas or lesions develop, the infected berries get mummified, later become hollow ( Pollu ). On developed berries, cracks develop on the pericarp or berries and radially split leading to dry weight loss. @ cpsskerala.in

21. Pathogen: Causal organism: Colletotrichum gloeosporioides and Colletotrichum necator   Mycelium septate , conidiophore bears conidia which are falcate, hyaline, unicellular with narrow ends. Acervuli and setae present.

22. Favourable condition: The infection is noticed during June at the time of spike emergence. Monsoon season.

23. Mode of spread: Primary spread: Ascospores from infected plant debris. Secondary spread: air borne conidia.

24. Management: Remove and destroy all fallen leaves and spikes. Irrigating vines during summer months. Adequate shade regulation is a must for managing this disease. P. fluorescens 20g/L of commercial formulation, once before flowering and then at berry formation stage. Spray COC 0.2% (2g/L) or Bordeaux mixture 1%. In the severely infected gardens, spray Carbendazim at 0.1%

25. 3. SLOW DECLINE @ cpsskerala.in

26. Symptoms: Foliar yellowing, die back of aerial stems, occasional tip burn, interveinal chlorosis and flaccidity of leaves. The affected plants dies within 2-5 years. @www.kisansuvidha.com

27. The root system of the affected vines shows the presence of root knots and root. With the onset of south west monsoon during May/June, some of the affected vines recover and put forth fresh foliage. The symptoms reappear in subsequent seasons after the cessation of the monsoon and the diseased vines gradually lose their vigour and productivity. @ researchgate.net

28. Pathogen: This disease is a fungal nematode chromista complex coupled with moisture stress and malnutrition. Pathogenecity of Meloidogyne incognita and Radopholus similis has been established. Association of Rhizoctonia sp ., Fusarium sp and Diplodia sp .

29. Meloidogyne incognita Radopholos similis @ en.wikipedia.org

30. Favourable conditions: Rainy seasons and loamy light soils favours the development of disease.

31. Mode of survival: Fungus survives in disease plant debris. Cysts and egg masses in infected plant debris and soil or collateral and other hosts like Solonaceous , Malvaceous and Leguminaceous plants act as sources of inoculums. Spread: Autonomous second stage juveniles that may also be water dispersed .

32. Management: Raise pepper cuttings in solarized nursery mixture. Use nematode free rooted cutting for planting. Apply green mulch of Eupatorium odoratum at the rate of 45tonnes /ha. Treat the vines with native isolates of Mycorrhizae / Trichoderma / Pseudomonas / Bacillus macerans / B. cerculans at the time of planting in the nursery as well as in the main field. Assure root mealy bug control if observed. .

33. 4. STUNT DISEASE Causal organism: Piper nigrum strain of Cucumber mosaic virus @ cpsskerala.in

34. 5. PHYLLODY DISEASE Causal organism: Phytoplasma @ vikaspedia.in /agriculture

35. 6. BASAL ROT Causal organism: Sclerotium rolfsii @ vikaspedia.in /agriculture