Author: SHAILENDRA KUMAR
Capsicum, a cool season vegetable crop also known as sweet pepper, bell pepper or Shimla Mirch. It is rich source of Vitamin A (8493 IU), Vitamin C (283 mg) and minerals like Calcium (13.4 mg), Magnesium (14.9 mg) Phosphorus (28.3 mg) Potassium, (263.7 mg) per 100 g fresh weight. It is long duration crop under greenhouse which requires day temperature of 25-30 0C and night temperature of 18-200C with relative humidity of 50- 60%. So year round cultivation of capsicum under polyhouse is possible by manipulating the environmental conditions as temperature, humidity, light intensity, etc which makes an effect on yield, quality and market value of the produce but these environmental changes also favor several biotic and abiotic diseases. Hence the identification and management practices to control disease at right stage of the crop should be given importance. The major diseases, diagnosis symptoms and their management in capsicum are given below:
- Damping off
It issoil borne disease which is transmits from previous season crop or nursery during transplanting. The moist soil having poor drainage with 90-100% humidity, 200 C soil temperature is most suitable condition form damping off under green house. Damage to roots during transplanting because wilting later seedling died with damping off.
Diagnosis symptom : The disease affects stem just above the ground surface at collar region of seedling. Darkening, thinning of stem in the primary symptom, later the stem is collapse from collar region and seedling is fall down. Very few roots are observed in affected seedling and can be plug out easy.
- Crop rotation.
- Soil solarization/ Soil sterilization if crop rotation is not followed.
- Sterilize well decomposed manure or compost or neem cake or vermicompost additive with Trichoderma spp. Or Pseudomonas fluorescens should be use in green house at the rate of 10 gram/ml per liter of water.
- Transplanting of healthy disease free seedling.
- Uprooting of affected seedling.
- Drenching at the base of plant with Carbendazim 50 WP @ 1g/L or Metalaxyl MZ @ 2g/L or Copper oxychloride 50 WP @ 3g/L or Captan 75 WP @ 3g/L at about 25-50 ml/plant.
- Powdery Mildew
It is air borne disease which generally appears at initial stage of leaf development. The warm temperature, low light condition favors disease development under green house.
Diagnosis symptoms: Initially yellow tiny spot develops on upper surface of leaf. The spots necrotize and simultaneously whitish powdery growth appears at lower surface of leaves. The leaves fully covered with powdery mass, dry and fall down at later.
- Sanitation; collection and destruction of fallen leaves.
- Spray Pongamia /Neem oil (7ml/L) + Sulphur WDG-80 (2g/L) or Wettable sulphur (2g/L) or Hexaconazole 5 EC (0.5ml/L) or Dinocap 46 EC (1 ml/L) or Azoxystrobin 25 EC (0.5ml/L) at fortnight intervals.
- Cercospora Leaf spot
It is seed borne disease. Primary source of inoculums is infected seed or seedling or infect plant debris. Under green house disease spreads with air. The warm climate with wet condition favors disease development.
Diagnosis Symptom: The disease appears as tiny pale circular spot having reddish-brown margin, surround by yellow halo ring on leaf surface. The spot enlarges cover leaf surface, later covert into dark gray color resulting drooping of leaf.
Management: Spray of Chlorothalonil 75 WP @ 2.5g/L) or Mancozeb 75 WP @ 2.5g/L or Carbendazim 50 WP @ 1g/L.
- Phythopthera Blight
It is soil borne disease. The water splash carry pathogen into canopy leads to leaf, stem and fruit infection. High and continuous rainfall coupled with high humidity favors disease development.
Diagnosis Symptoms: Tiny oil like spot develops on leaf surface which later turn black in color and start rotten. The collar rot and brown discoloration also appear on stem with wilting that is extended toward base of plant.
- Affect plant part should be destroy immediately.
- Spray copper hydroxy chloride 77 WP (3g/L) or Bordeaux mixture (1%) or Metalaxyl MZ (2g/L) or Dimethomorph + Mancozeb (1 g + 2.5g/L) or Fosetyl aluminium (2g/L) or Azoxystrobin 25 EC (0.5ml/L).
- Leaf curl Complex
It is viral disease which is transmit by insects mainly aphid, thrips, whitefly and mites in green house. The disease can be carry with seedlings if infection occurs during nursery stage. The infected plant cannot recover after penetration of virus into plant system. Thus it causes great loss in green house.
Diagnosis Symptom: Reduction in size of leaves, shortening of veins, puckering, mottling of the leaves, stunting and bushy appearance of the plant is symptoms of viral infection. Conspicuous outgrowth and prominent veins are visible on lower side of the leaves. Downward rolling, narrowing and shortening of leaves due to mite infestation were observed.
- Use of disease tolerant varieties.
- Raise disease free nursery seedlings under insect proof nylon net.
- Root of seedling should be dipped in Imidacloprid 17.8 SL @ 4-5 ml per liter of water for one hour during transplanting.
- Roughing and burning of infected plant expeditiously.
- Periodical spray of Spiromesifen 22.9% SC @ 1 ml per liter of water with Wettable Sulpher @ 0.2%.
- One to two spray of Imidachoprid 17.8 SL @ 0.3 ml per liter water or Thiamethoxam 25 WG @ 0.4 gram per liter of water.
1. Protection cultivation of Capsicum, Technical bulletin no.22, IIHR, Bangalore.
2. Integrated Pest Management, Schedule for Vegetable, Technical bulletin no. 6, National Horticulture Mission, Department of agriculture and cooperation, Ministry of Agriculture.
3. AESM based IPM package No. 24, Chill/Capsicum, Department of Agriculture and Cooperation, Ministry of Agriculture, Government of India.
4. Katoch and Kapoor, Fungal disease of Capsicum and their management, popular kheti, Volume -2, Issue-2 (April-June), 2014.
5. Albajes, R., Lodovica Gullino, M., Van Lenteren, J. C and Elad, Y. Integrated Pest and disease management in green house crops, Kluwer Academic Publishers, New York, Boston, Dordrecht, London, Moscow. 2002.
6. Kumar, J. Biological control of soil borne pathogen under green house condition. Pp. 134-140. Proceedings of the 26th Training on "Disease and management of crop under protected cultivation" September, 04-24, 2012.
About Author / Additional Info:
I am Plant Pathologist. Currently providing my services in Agricultural Private Sector.