TOMATO

Pests

Tomato fruit worm (Heliothis armigera)

Caterpillars feed on leaves and other vegetative parts in the initial stage. Later cause extensive fruit damage by entering through cut holes and burrows and feeding the internal content. Infestation is severe during October-March.

Control: Judicious use of synthetic pyrethroids like fenvalerate (50g a.i./ha) or deltamethrin (10g a.i./ha) controls the fruit borer.

Epilachna beetles (Epilachna vigintioctopunctata)

The yellowish grubs and adults feed voraciously on the leaves and tender parts of the plant, and completely skeletonizes the leaves leaving only a network of veins. The pest often causes serious defoliation when appeared in large number.

Control: Collection and destruction of infested leaves along with the grubs, adults and eggs reduces the pest incidence. Spraying malathion (2ml/litre of water) or carbaryl (2-4 g/litre of water) effectively controls the pest.

Jassids (Amrasca biguttula biguttula, Cestius phycitis)

Nymphs and adults of the pest suck sap from the lower surface of the leaves and infested leaves curl upward along the margins, turn yellowish and show burnt up patches. Fruit setting is also adversely affected. The pest is the natural vector of mycoplasmal disease like little leaf and viral disease like mosaic.

Control: Spray malathion (0.1%) or dichlorvos (0.05%) 20 days after transplanting.

Tabacco caterpiller (Spodoptera litura)

Caterpillars feed gregariously on tender leaves, shoots and fruits at night. The pest is confined to nursery beds and assumes cutworm habits. The adult moths are greyish brown coloured with white marking on upper wings.

Control: Spray nuvan (0.5 ml/ 2 litres of water). Avoid the use of highly toxic insecticides.

Whitefly (Bemisia tabaci)

Minute milky white flies and their nymphs suck cell sap from the leaves.  The affected leaves curl and dry up, and growth of the plant is stunted. White flies act as a vector of leaf curl virus causing severe yield loss.

Control: Soil application of carbofuran (24 kg/ha) before transplanting is recommended for the control of white flies. Alternately, 2-3 sprayings with monocrotophos (0.02%) or phosphamidon (0.02%) at fortnightly intervals starting with the appearance of the pest also effectively control the pest.

Mites (Tetranychus cucurbitae)

Nymphs and adults suck cell sap from the foliage and flower buds.  White patches appear on the affected leaves. The leaves later become mottled, curl, turn brown and fall. Different stages of mite are found in colonies covered by white-silky webs on lower surface of leaves. Low relative humidity favours mite multiplication.

Control: Proper irrigation and clean cultivation practices including cutting and burning of severely infested plant parts help to keep the pest population under control. Acaricides like dicofol (0.05%) and wettable sulphur (0.3%) gives effective control of mites.

Root-knot nematodes (Meloidogyne spp.)

The nematodes invade the roots of tomato forming characteristic galls on roots. The symptoms of aerial infection include stunted plant growth, chlorosis and tendency to wilt under moisture stress during hot, dry weather. When the nematode population is high, plants of a susceptible variety may die before reaching maturity.

Control: Complete elimination of nematodes from field is not possible. However, use of resistant varieties and crop rotation with non-host crops like marigold, maize, onion etc. reduces the nematode infestation. Application of neem oil cake (1-1.5 t/ha) 15 days after transplanting also helps to suppress the nematode population.

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Last updated: 10-06-2008