Post harvest diseases of Chilli

1. Symptoms and management of post harvest disease of chilli

2. Submitted by:Name : LimbachiyaMilind Reg. No. : 3010716024Sub.: Cr.Prot.8.2 :Management of Post Harvest Insect Pests and Dieses • Submitted to : • Dr. R.R.Waghunde Sir

3. Post Harvest Diseases ofChilli • Bacterial soft rot –Erwiniacarotovora subsp. Carotovora • Anthracnose – Colletotrichumcapsici • Alternaria rot – Alternariasolani • Gray mould – Botrytis cinerea • Late blight – Phytophthoracapsici

4. Bacterial soft rot – Erwiniacarotovorasubsp. carotovora Symptoms: • Dark venial tissue followed by leaf chlorosis and necrosis • Internal Dark brown discoloration • Stem cankers develop – breakage of branches • Wilting and drying • Fruit peduncle - highly susceptible & is frequently the initial point of infection • Both ripe and green fruits ma be affected

5. Initially, the lesions the fruits are light to dark- coloured , water soaked, and somewhat sunken • In later stages, bacterial ooze may be develop from affected areas, and secondary organisms follow, often invading the rotted tissue • Affected fruits hang from the plant like a water-filled bag

6. Identification of pathogen: • The bacterium is gram negative , rod shaped with 1-6 peritrichous flagella.

7. Management: Disease incidence could be reduced by • Early detection of symptoms • Disinfection of pruning tools • Avoidance of wounding plants • Remove plant debris- fallen , diseased leaves • Seed treatment- 1% sodium hypochlorite for 30 sec , then rinse with clean water • Avoid planting pepper crops following crops potato or cabbage • Rotate instead with crops of beans, corn and soyabean

8. Post harvest diseases management • Use chlorinated water to reduce populations of soft rot bacteria and to reduce the risk of infection during washing • Allow fruit to dry thoroughly • During packing and storage , the fruits should be kept clean and maintained in a cool, dry place

9. Anthracnose- Colletrichumcapsici Symptoms: • Ripe fruits turning red are affected • Small, black, circular spot appears on the fruit skin • Badly diseased fruits turn straw colour or pale white colour , lose their pungency

10. Identification of Pathogen • Diseased cut open fruits – lower surface of the skin is covered with minute, elevated sclerotia • Advanced stages – seeds covered by a mat of fungal hyphae , turn rusty in colour • Mycelium – septate and inter and intracellular • Acervuli and stroma on the stem are hemispherical • Conidia – in mass appear pinkish

11. Favourable condition: • Temp – 28° C., RH – 95% • High humid conditions when rain occurs after the fruits have started ripe Mode of spread: • Seed borne • Secondary spread is by air borne conidia & rain • Flies and other insects – responsible for dissemination of the spore from one fruits to another

12. Management: • Use diseases free seed • Seed treatment – thiram 2kg/ha or zineb 2.5 kg/ha • Three spraying with captan 0.2% 1st spraying just before flowering, 2nd at the time of fruit formation, 3rd fortnight interval after second spraying Biocontrol: • P.fluorescens, bacillus subtilis-effective (rajavel,2000) • P.fluorescensand T.viride (Muthuraj,1998) • Essential oil – Nigella sativa – antimicrobial activity

13. Gray mould - Botrytis cinerea Symptoms: • Brownish spots develop near the soil line or cotyledons • Water soaked lesions on leaves & steam darken and collapse

14. Water soaked spots that rapidly expand into large yellowish-green or grayish-brown, irregular lesions that are soft and spongy in texture • Velvet like fungus mycelium and spores are produced on the lesions surface under cool, humid conditions Identification of pathogen: • Botrytis cinerea- abundant hyaline conidia ( asexual spores) borne on grey, branching tree like conidiophores • It overwinter as sclerotia or intact mycelia, both of which germinate in spring to produce conidiophores • The conidia are dispersed by wind and rain water and cause new infections

15. Favourable condition and spread: • Fungus sporulation and infection , is favored by cool and wet weather • Tem. Of 17°-23° C. , RH – 90% • Excessive application of nitrogen makes plants such as young transplants more susceptible to gray mold • High canopy density creates conditions for extended leaf wetness at night and subsequent increased gray mold severity

16. Management: • Field sanitation – remove and burn decaying infected plant parts • Space seedling and transplants to allow for free flow of air through the crop • Treatment with hot air at 38° C for 48-72 hr or hot water at50°C to 53° C for 2-3 min

17. Alternaria rot - Alternariasolani Symptoms: • Brown lesions surrounded by a yellow halo develop on the fruits • Lesions enlarge and result in the formation of irregular sunken patches with a dark brown margins and light grey centre

18. Identification of pathogen: • Hyphae : septate, branched, light brown becoming darker with age • Conidia – single, muriform, braked and dark in colour • Source of infection – infected seeds and plant debris Management: • Fortnightly spraying of : BM 1.0% , Copperoxychloride 0.3%, Difolatan 0.3%, Mancozeb 0.2% • Reduction in the pathogenicity and development of these pathogen in inoculate peppers, • Treatment with hot air at 38° C for 48-2 hr • Hot water treatment at 50°-53° C for 2-3 min

19. Late blight - Phytophthoracapsici Symptoms: • Infected leaf tissue – wilted , light green or gray-green, later becoming tan to white and scalded in appearance • With moisture, leaf spots have a water soaked water

20. Fruits rot – irregular in shape and olive green or light green with water soaked border • Rot expand rapidly and fruits can be completely diseased and desiccated, causing the formation of “mummified” fruits • Infected seeds are brown and shriveled Identification of pathogen : • Produces microscopic, asexual spores called sporangia • Sporangia – spherical to pyriform, hyaline, papillate and have a long pedicel attached to the base of the spore • Pathogen grows well between 25°-30° C

21. Mode of spread : • Survives in the soil in host debris • Roots, stems, and mummified fruits left in the field after harvest, harbor the pathogen for months • Phytophthoracapsiciis also seed borne Management: • Rotation with non-susceptible crops will reduce the amount of Phytophthoracapsicisurviving in soil • Fresh, clean seeds should be planted in new potting mix to establish healthy transplants • Monitor seedlings as well as the field and remove diseased plants as soon as they occur