ArticlePDF Available

Fungal Diseases of Chilli and their Management

Authors:

Abstract

Chilli (Capsicum annum L) is an excellent source of vitamin A, B and C besides its pungency and medicinal uses. It is vulnerable to various fungal, bacterial and viral diseases which hampered its production and productivity. The disease can affect the yields through reduction of photosynthetic area in early stages and infestation on reproductive parts and economic produce at later stages. The disease causes a reduction on photosynthate flow in the plant (equivalent to blocking of pipes). The present topics will detail about the important fungal diseases of chilli their symptoms, epidemiology and management practices.
AgriCos e-Newsletter
0000
Volume : 01 Issue : 03 July 2020 Article No: 16
www.agricosemagazine.com 47
Bijeeta Thangjam1, Wangkhem Tampakleima Chanu1 and Bandana Mayanglambam2
1 Ph.D Scholar, Department of Plant Pathology, College of Agriculture, CAU, Imphal, Manipur
2 Ph.D Scholar, Department of Plant Pathology, BCKV, Mohanpur, Nadia, West Bengal
SUMMARY
Chilli (Capsicum annum L) is an excellent source of vitamin A, B and C besides its pungency and
medicinal uses. It is vulnerable to various fungal, bacterial and viral diseases which hampered its production and
productivity. The disease can affect the yields through reduction of photosynthetic area in early stages and
infestation on reproductive parts and economic produce at later stages. The disease causes a reduction on
photosynthate flow in the plant (equivalent to blocking of pipes). The present topics will detail about the important
fungal diseases of chilli their symptoms, epidemiology and management practices.
INTRODUCTION
Chilli (Capsicum annum L.) is mainly cultivated for its vegetable green fruits and the dry chilli as the
spice of commerce. It is a rich source of Vitamin C, A and B. Chillies are cultivated mainly in tropical and sub-
tropical countries like India, Japan, Mexico, Turkey, United States of America and African countries. India is an
important cash crop, which is grown for both the domestic and export market. India is the largest producer of
chillies in the world (8.5 lakh tones) followed by China (4 lakh tonnes), Pakistan (3 lakh tonnes) and Mexico (3
lakh tonnes). India is well known as the land of spices the world over. Capsicum species are used as fresh or dried,
whole or ground, and alone or in combination with other flavouring agents. Capsicum annuum L. is used in sweet
bell peppers, paprika, pimento, and other red pepper products. The most notable feature of capsicum is its flavour
which is an excellent source of vitamin A and C besides its pungency and medicinal properties. The capsicum is
vulnerable to various bacterial, fungal and viral diseases, which are responsible for taking away a big chunk of
production. The major fungal diseases are discussed below.
Factors Influencing Disease Symptoms
Host-parasite relation: The intensity of the disease depends upon the susceptibility / resistance of the host to the
pathogen.
Environmental factors: can be grouped as Soil borne seed borne and Air borne
Soil borne: Soil pH, Structure, Texture Moisture, Organic matter, fertility, cultural operations, Irrigation.
Seed Borne: Seed Moisture, Storage environment
Air Borne: Temperature, RH, and Rainfall Wind.
1.Die Back/ Anthracnose:
Causal organism: Colletotrichum capsici
Symptoms: As the fungus causes necrosis of tender twigs from the tip backwards the disease is called die-back.
Infection usually begins when the crop is in flower. Flowers drop and dry up. There is profuse shedding of flowers.
The flower stalk shrivels and dries up. This drying up spreads from the flower stalks to the stem and subsequently
causes dieback of the branches and stem and the branches wither. Partia1ly affected plants bear fruits which are
few and of low quality.
Epidemiology: The pathogen overwinters in crop debris and infected seeds, fruits. The disease is favoured by
cloudy weather, heavy rains and dew
Management
Use of disease-free seeds is important in preventing the disease
Seed treatment with Thiram or Captan 4g/kg is found to be effective in eliminating the seed-borne inoculum.
Good control of the disease has been reported by three sprayings with Ziram 0.25% or wettable sulphur 0.2%
or copper oxychloride 0.25% or zineb 0.15%. The first spraying should be given just before flowering and the
second at the time of fruit formation. Third spraying may be given a fortnight after second spraying. Chilli
cultivar BG-1, Lorai and Perennial are found to be resistant against the disease
Fungal Diseases of Chilli and their Management
AgriCos e-Newsletter 01 (03) July 2020 Bijeeta et al.
www.agricosemagazine.com 48
2.Cercospora leaf spot :
Causal organism: Cercospora capsici
Symptoms: Leaf lesions typically are brown and circular with small to large light grey centres and dark brown
margins. The lesions may enlarge to 1cm or more in diameter and sometimes coalesce. Stem, petiole and pod
lesions also have light grey centres with dark borders, but they are typically elliptical. Severely infected leaves
drop off prematurely resulting in reduced yield.
Epidemiology: The fungus survives on seed and in crop residue. The conidia are disseminated by wind, rain or
intercultural operation tools. The fungus sporulates abundantly at 20-300C, but reduces at 100C and stop at 400C.
Management
Crop debris should be removed and burnt.
Seed should be collected from healthy plants.
Spray twice at 10-15 days interval with Mancozeb@0.25% or Chlorothalonil@0.1%., Captafol @03.% or
Triadimefon @0.1%.
3. Phytophthora Leaf Blight and Fruit Rot
Causal organism: Phytophthora capsici
Symptoms: All the plant parts are affected and the severity of the disease varies depending upon the climatic
conditions and locality. Fruit rot phase of the disease is highly destructive with water-soaked, dull green spots
appear on the fruit, gradually expanded and becomes mummified. Leaf lesions are dark green, water-soaked,
round or irregularly shaped area which expands rapidly.
Epidemiology: The pathogen survives in infected crop debris or the soil and association with other crops such as
cucurbits, brinjal and tomato. Oospore serves as a survival structure. Warm temperature in combination with high
humidity is favourable for disease development.
Management:
Cultural practices such as crop rotation, timely roughing of diseased plants, parts, avoid contact of fruits and
leaves to ground soil, use of disease-free seed, mulching with straw, earthling up of plants after transplanting
are recommended.
Biological control such as Pseudomonas cepacia, Bacillus polymixa and Streptomyces violaceoniger are
effective against the disease.
Application of fungicides such as a mixture of Metalaxyl-copper oxychloride, metalazyl-dithianon, Oxadixyl-
Chlorothalonil has been reported effective in the control of both fruit rot and anthracnose.
4. Fusarium Wilt:
Causal organism: Fusarium oxysporumf.sp.capsici
Symptoms : Fusarium wilt is characterized by wilting of the plant and upward and inward rolling of the leaves.
The leaves turn yellow and die. Generally appear as localized areas of the field where a high percentage of the
plants wilt and die, although scattered wilted plants may also occur. By the time above-ground symptoms are
evident; the vascular system of the plant is discoloured, particularly in the lower stem and roots.
Epidemiology: High temperature and wet soil conditions favour disease development and more severe in poorly
drained soils. The organism grows and sporulation best at 20 to 300C
and 5 to 8 pH.
Management
Use of wilt resistant varieties.
Drenching with 1% Bordeaux mixture or Blue copper 0.25% may give protection.
Seed treatment with 4g Trichodermaviride formulation or 2g Carbendazim per kg seed is effective.
Mix 2kg T.viride formulation with 50kg FYM, sprinkle water and cover with a thin polythene sheet. When
mycelia growth is visible on the heap after 15 days, apply the mixture in rows of chilli in an area of one acre.
5.Powdery Mildew:
The disease was first reported from Morocco in 1937.
AgriCos e-Newsletter 01 (03) July 2020 Bijeeta et al.
www.agricosemagazine.com 49
Causal organism: Leveillula taurica
Symptoms: First disease symptoms are noticed on the older leaves which progress to younger leaves. The infected
leaf is covered with white to grey powdery masses of the fungus where lower leaf surface also turn necrotic. The
heavy infection leads to leaf shedding resulting in heavy losses in yield.
Epidemiology: Cultivated and wild hosts such as Cynaracardunculus, Cicerarietinum, Lucerne, Oxalis cernaare
the source of the pathogen during offseason. The optimum and maximum temperature for disease development
is 200C. Temperature above 300C appears to be lethal for the fungus.
Shedding of foliage
Management
Spray with Wettablesulphur@0.25% or Dinocap@ 0.05%2-3 times at 10 -15 days interval.
Varieties such as B 15, R 7, Padasali, Tinwari, Golden Superior have been reported as moderately resistant.
6. Damping-Off
Causal organism: Pythium aphanidermatum
Symptoms: Symptoms appears as water-soaked lesions at the collar region, infected areas turn brown and rot
and plants shrivel and collapse as a result of softening of tissues. Disease of nursery beds and young seedlings
resulting in reduced seed germination and poor stand of seedlings.
Epidemiology: High soil moisture and relatively higher soil temperature favour the rapid development of the
disease. The disease is further aggravated in ill- aerated soils with poor drainage having thick stand of the
seedlings
Management:
Soil drenching with Copper oxychloride 0.25%
Avoid shade places for nursery establishment
Use the recommended seed rate
Avoid flooding type of irrigation and maintain the optimum moisture level in the nursery
Use Thiram or Captan @ 4g/ kg of seeds for seed rate.
CONCLUSION
The major fungal diseases of chilli are phytophthora leaf blight and fruit rot, anthracnose, cercospora
leaf spot, powdery mildew and damping off. Knowledge about the different symptoms and epidemiology will
help in the detection and diagnosis of different diseases. Leaf blight and fruit rot are highly destructive resulting
in complete failure of the crop. Timely application of control measures such as application of fungicides can
minimize the foliar diseases. Soil borne diseases can be reduced by crop rotation, soil solarization, growing
resistant varieties and also application of biocontrol agents.
REFERENCES
Agrios GN. Plant Pathology. 5th Ed. San Diego: Academic Press; 2005. p. 922.
Blazquez, C. H. (1976). A powdery mildew of chilli caused by Oidiopsi. sp. Phytopathology, 66(10), 1155-1157
Bosland PW, VotavaS EJ. Peppers: Vegetable and Spice Capsicums. England: CAB International; 2003. p. 233.
Dodd JC, Estrada A, Jeger MJ. Epidemiology of Colletotrichum Gloeosporioides in the Tropics. In: Bailey JA,
Jeger MJ, editors. Colletotrichum: Biology, Pathology and Control. Wallingford: CAB International;
1992. pp. 308325.
Madhavi, G. B., & Bhattiprolu, S. L. (2011). Integrated disease management of dry root rot of chilli incited by
Sclerotium rolfsii (Sacc.). International Journal of Plant, animal and environmental sciences, 1(2), 31-
37.
Than, P. P., Prihastuti, H., Phoulivong, S., Taylor, P. W., & Hyde, K. D. (2008). Chilli anthracnose disease caused
by Colletotrichum species. Journal of Zhejiang University Science B, 9(10), 764.
ResearchGate has not been able to resolve any citations for this publication.
Article
Full-text available
Chillies is an important commercial crop of Andhra Pradesh. Recently the crop is affected by dry root rot disease caused by Sclerotium rolfsii (Sacc.) under rainfed conditions. An attempt was made to manage the disease by holistic approach. In vitro evaluation of nine fungicides by poison food technique showed that tebuconazole and combination of carbendazim+mancozeb were effective in inhibiting the mycelial growth (94.1%) followed by difenconazole (93.3%). In vivo soil drenching with same fungicides proved effective in controlling the pathogen at 1000, 2000 and 3000 ppm. Integration of different treatments including seedling dip with carbendazim+mancozeb, addition of vermicompost, drenching with fungicide and application of Trichoderma harzianum (7%) were found to be effective in management of disease in comparison with individual treatments. Chilli (Capsicum annum L.) is mainly cultivated for its vegetable green fruits and for the dry chilli as the spice of commerce. It is a rich source of Vitamin C, A and B.In India it is an important cash crop, which is grown for the both domestic and export market.. India is the largest producer of chillies in the world (8.5 lakh tones) followed by China (4 lakh tonnes), Pakistan (3 lakh tonnes) and Mexico (3 lakh tonnes). Andhra Pradesh ranks first in India both in area and production with 2.04 lakh hectares producing 323 thousand tones (Anonymous, 2010). Chilli crop suffers with many fungal, bacterial and viral diseases resulting in huge yield losses. Among the fungal diseases, in recent years dry root rot of chilli caused by Sclerotium rolfsii is of major concern and causing the economic losses in chilli (Kalmesh and Gurjar 2001). In the year 2001 root rot of chilli caused by S. rolfsii was first time reported from Rajasthan near Jaipur chilli growing areas, where the sever mortality of chilli plants during March-April was observed (Kalmesh and Gurjar (2001). Survey of the disease over a period of time revealed that the it affects the yield severely whenever it occur at any stage of the crop. Inspite chemical measures like drenching copper oxy chloride @3 g/L is recommended based on the previous studies on Sclerotium spp., the new fungicides along with earlier proven fungicides need to be evaluated to find out the effective and economic fungitoxicants with which the disease can be controlled. Presently, greater emphasis should be placed on biological control of soil borne pathogens, in order to reduce the cost of cultivation, environmental hazards and to avoid the development of resistant strains. . Hence, a holistic approach is needed for the effective management of root rot disease.
Article
Full-text available
Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.
Peppers: Vegetable and Spice Capsicums. England: CAB International
  • P W Bosland
  • E J Votavas
Bosland PW, VotavaS EJ. Peppers: Vegetable and Spice Capsicums. England: CAB International; 2003. p. 233.
Epidemiology of Colletotrichum Gloeosporioides in the Tropics
  • J C Dodd
  • A Estrada
  • M J Jeger
Dodd JC, Estrada A, Jeger MJ. Epidemiology of Colletotrichum Gloeosporioides in the Tropics. In: Bailey JA, Jeger MJ, editors. Colletotrichum: Biology, Pathology and Control. Wallingford: CAB International; 1992. pp. 308-325.