TOMATO DISEASES

 

 Tomato – 

Plant description: T omato (Lycopersicon esculentum L.; Family Solanaceae) is one of the most important protective food crops of India. It is grown in 0.458 M ha area with 7.277 M mt production and 15.9 mt / ha productivity. The plants typically grow to 1-3 meters in height and have a weak stem that often sprawls over the ground and vines over other plants. It is a perennial in its native habitat, although often grown outdoors in temperate climates as an annual. 

The plant is herbaceous, annual have a basal or terminal group of leaves. The leaves are generally alternate or alternate to opposed (that is, alternate at the base of the plant and opposed towards the inflorescence). The leaves can be herbaceous, leathery and are generally petiolate or subsessile, rarely sessile. The leaves have reticulated venation and lack a basal meristem. 

The flowers are hermaphrodites. The flowers can be solitary or grouped into terminal, cymose, or axillary inflorescences. The flowers are usually actinomorphic. The flowers have a differentiated perianth with a calyx and corolla (with five sepals and five petals, respectively) an androecium with five stamens and two carpels forming a gynoecium with a superior ovary. 

The stamens are epipetalous and are typically present in multiples of four or five, most commonly four or eight. They usually have a hypogynous disk. The major tomato producing states are Bihar, Karnataka, Uttar Pradesh, Orissa, Andhra Pradesh, Maharashtra, Madhya Pradesh and West Bengal. Tomatoes are rich source of vitamins A, C, potassium, minerals and fibers. Tomatoes are used in the preparation of soup, salad, pickles, ketchup, puree,

EARLY BLIGHT

is a common leaf spot caused by the fungus Alternaria solani. Dark brown spots with broad yellow haloes appear on the leaves, and concentric rings can be found in the spots under bright light. Stems and fruit can also be infected. It often progresses from the bottom of the plant upward. Cool humid weather or overhead irrigation encourage Early Blight, which is spread by splashing water and germinates on moist leaves.

 CONTROLS : Avoid getting water on the leaves whenever possible, change the locations where you plant your tomatoes, mulch well around each plant, and clear away all dead or infected plant material at the end of each season. Picking off infected leaves may slow the progression of the disease until the weather is more favorable

SPECK AND SPOT 

are bacterial diseases with similar symptoms, causing small black specks or patches on leaves, stems, and fruit. They can be distinguished from Early Blight by the water-soaked appearance of the spots, and the fact that the spots do not cross the larger veins. Like Early Blight, these bacterial diseases are spread by water, and they can overwinter in soil and on debris from the previous season. 

CONTROLS : Prevent and control these diseases as you would Early Blight, above. Bacterial spots stop spreading in dry, warm weather. Chemical controls are usually not needed.

LATE BLIGHT is caused by Phytophthora infestans, a fungal disease most famous for the Irish potato famine. It is just as serious in tomatoes, causing dark green to purple-brown water-soaked spots that grow quickly on leaves and stems. The underside of infected leaves will sometimes have whitish powdery spores. Fruit turns brown but stays firm. The fungus thrives during periods of high humidity and mild temperatures (60-78 ° F). Once it gets going, it can kill a plant very rapidly and spread to other tomatoes, peppers, or potatoes. 

CONTROLS: Avoid sprinkler irrigation, very dense planting, or other things which keep humidity high. Remove volunteer potatoes or tomatoes, and clean up debris at the end of the season. Mulching may help prevent initial infection.