Fungal Disease of Tomato and Its Management
Authors:
Prof. Jiitendra E. Wayde, Assistance Professor (Genetics and Plant Breeding), H.H.S.S. Muralidhara Swamiji College of Agriculture, Malegaon, Nasik, Maharashtra, India.
Prof. Shilpa K. Udamale, Assistance Professor, (Dept. of Botany), H.H.S.S. Muralidhara Swamiji College of Agriculture, Malegaon, Nasik, Maharashtra India.
Dr. Manoj kumar Bahel, Assistance Professor (Genetic and Plant breeding) Lovely Professional University, Jalandhar, Punjab, India.

Introduction:

Fungal diseases can be a major problem of tomatoes. It is soil borne disease in plants. Fungi live and obtain their intake from infected host tissue. It is replicate by spores, small microscopic bodies, which are spread with water wind and other mechanical means to a new host.it is spores germinate and host specific infect to plant tissues causing rots, wilt, leaf spots it leads to defoliation and reduced to yield of tomato. Fungi is developed and spread in home garden and determine rainfall, humidity, free moisture and temperature.

Most common fungal disease is infecting for tomatoes grown in home garden in early blight, late blight, leaf spot, fusarium wilt all are produce distinct symptoms.

Early Blight (Alternaria solani):

Early blight can infect tomato foliage and fruit. On Early blight first appears as circular irregular black or brown spots on the older leaves of the plant. Early blight can infect the fruit through the calyx or stem attachment in the immature green or red stage and can produce distinct target-like lesions similar to foliar infection. Defoliation caused by early blight can reduce fruit yield and can leave the fruit open to sunscald injury.

Late Blight ( Phytophthora infestans) :

The disease will first appear as greasy grayish indefinite patches on older leaves and stems. These spots enlarge in moist weather and may produce white fuzzy growth on the underside of infected leaves. The fungus will also attack fruit early blight lesion on infected tomato leaf with distinct concentric rings. Early blight causing rot on petal end of infected tomato fruit.

Fusarium Wilt (Fusarium oxysporum):

Wilt diseases are caused by pathogens that invade the vascular system and disrupt water flow through the plant. Fusarium wilt is the major wilt disease of tomato. The first symptom is usually a yellowing of the lower leaves, which gradually wilt and die. Symptoms may first occur on only one side of the plant. The disease progresses up the stem until all of the foliage is killed and the plant dies. If stems or petioles from wilted areas of diseased plants are cut, a reddish-brown discoloration can be seen between the pith and the outer green part of the stem.

Southern Blight (Sclerotium rolfsii):

Southern blight can be a devastating disease of tomatoes. The southern blight fungus has a wide host range attacking more than 200 species of plants that include common weeds and crop plants.

The initial symptom of southern blight is a rapid wilting of the entire plant. A water-soaked lesion on the stem near the soil line rapidly expands, turns brown and girdles the stem. Sclerotia are first white, later becoming brown, and resemble mustard seeds.

Soil Rots

Soil rots are caused by several fungi which reside in soil and infect fruit in direct contact with the soil or are splashed into lower fruit near the soil. Warm, wet conditions and growth of tomatoes in poorly drained areas favor soil rot development. Ripe fruit is generally most vulnerable to soil rot development; however green fruit may also be affected.

Damping-off ( Pythium and Rhizoctonia ):

Wide host range, it is cause by pre- and post-emergence, damping-off, both favored by excess moisture P. aphanidermatum favored by high temperatures; P. ultimum by low temperatures.

Management of the disease:

Use Clean Seed: Treat seed with dilute Clorox or hot water

Seed borne fungal diseases is Septoria, Anthracnose, Early blight, Fusarium wilt.

Choose Resistant Varieties: Most are resistant to Fusarium wilt, Verticillium wilt, Root knot nematode, Partial resistance, Alternaria stem canker.

Use Pathogen Free Transplants: Transplant production conditions favorable for bacterial and fungal disease for Damping-off, Alternaria (early blight), White mold, Botrytis.

Use Pathogen Free Transplants: Scout regularly and destroy plants with symptoms is Minimize moisture “dry growing”, All fungal diseases of seedlings favored by excess moisture, Maintain warm conditions, Pythium damping-off, white mold, Botrytis favored by cool conditions, Use only municipal or well water avoid surface water unless it is treated to kill microorganisms, Pythium is a common water mold, Mancozeb applications help control early blight, White mold or Botrytis Fontelis or Scala (GH allowed) Choose the Best Site and Rotate, Site selection, Well drained, Good air movement, Sunny, Rotate out of the tomato, 3-4 years out of tomatoes if possible.

Use Best Cultural Practices: Avoid handling plants when they are wet, sanitize hands, boots and tools between fields, maintain reduced-stress growing conditions, well-drained soil, Appropriate fertilizer, Regular irrigation if needed, Improved organic matter content cover crops, compost, Clean and sanitize equipment between fields

Use Crop Protectants Program: Fungicide program depends on the Disease problems, Fungicide efficacy, Resistance management, Cost.


About Author / Additional Info:
I have completed M.Sc. in Agriculture (Genetic and Plant Breeding) from Lovely Professional University, Punjab