Tomato

Insect Management

Gram pod borer Heliothis armigera

Family Noctuidae
Order Lepidoptera

Adult

Polyphagous, attacks most of the cultivated crops, major pest of tomato, and widely distributed throughout the country.

Eggs

Larvae

• Moths are medium sized, stout, pale brown or with reddish brown tinge, fore wings are olive green to pale brown with a dark brown circular spot in the centre.
• Hind wings are pale-smoky-white with a broad dull blackish outer boarder.
• Eggs are yellowish white, ribbed, dome shaped, laid singly, generally on leaves and flowers, but some times on young fruits as well.
• Freshly hatched larvae are yellowish white. Full grown caterpillars are in varied colours, but generally apple green with whitish and dark grey or brown longitudinal lines, have on lower lateral part a broad white wavy line. Pupation is in soil.
• Life cycle is completed in 4-6 weeks.

Nature of damage

Circular holes on fruits

• Young larvae feed on tender foliage. while advanced stages attack the fruits.
• Larva bore circular holes and usually thrust only head inside the fruit to another and may destroy many fruits.
• External symptoms appear in the form of a bored hole.

Control

• For effective control of this pest an integrated package has to be adopted transplant two rows of marigold for every 16 rows of tomato, as a trap crop, as the female will be attracted to marigold flowers and lay eggs.
• To fecilitates synchronous flowering, plant 40 and 25 dats old seedlings of marigold and tomato, respectively, at a time.

Also monitor the pest through pheremone traps.

• Spray 5% neem seed kernel extract to kill early stages larvae Placement of 15-20 bird perches (T shaped) per ha helps in inviting insectivorous birds.
• Spray NPV @ 625 LE/ha during evening hours.
• Jaggery @ 1 kg, sandovit or Teepol(100 ml) are to be mixed with NPV on need basis spary 2 ml Endosulfan, Chlorpyriphos or Quinolphos per litre of water.

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Serpentine leaf miner Liriomyza trifolii

Family Agromyzidae
Order Diptera

• Pest introduced from U .S .A. in early ninetees.
• polyphagous, and very widely distributed throughOut India.

Adult is a tiny fly with thin, transparent wings, females have a prominent retractile ovipositor. Maggots are legless, pale yellow, body tapers anteriorly.

Nature of damage

Maggot mines into the leaf and feeds on the mesophyll of the leaves making serpentine mines. As the larva grows the diameter of the mine increases. Pupation is in soil and the entire life cycle is completed in about 15 days.

Control

• If infestations occur at the late stage of the crop, no chemical control may be needed.
• If early and severe, spray triazophos.

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Root-Knot Nematode Meloidogyne spp.

• Wide host range, widespread all over India, affects most of the vegetable crops, often tomato, brinjal, okra are worst affected.

Life cycle

• Root-knot nematodes are small, microscopic, males are slender and females swollen.
• Female lays about 500 eggs in a gelatinous matrix mostly outside root tissue.
• Eggs hatch in 4-7 days and the second stage larvae infect the plant by entering the roots.
• There they feed and moult to reach adulthood.
• The females become nearly spherical. Life cycle is completed in 4 to6 weeks.
• M.incognita and M.javanica are common species attacking vegetables.

Nature of damage

The most characteristic symptom on the root is production of root galls. Galls may occur singly or several galls may coalesce to form very massive galls. Above ground symptoms are reduced growth, chlorosis of foliage, susceptibility to wilting, and reduced fruit production.

Control

• Fallowing, deep summer ploughing and drying up infested soils reduce incidence.
• Nurseries are the main source of infection and spread. Ploughing the nursery area, uniformly spreading paddy husk 20 kg/m2 (about 15 cm thick), burning it and ploughing back facilitates production of nematode-free seedlings.
• Crop rotation with mustard is also usefu.l
• Application of chopped leaves of Pongamia or Crotalaria reduces disease severity.
• Nursery-bed treatment with Carbofuran 3 G at 65 g/m2 and in main field at 4 kg a.i/ ha are effective.
• Tomato varieties Nematox, SL-120, NTR-I, Nemared, Ronita, Anahu, Pelican are resistant.

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Tobacco caterpillar Spotoptera litura

Order Noctuidae
Family Lepidoptera

• Eggs are laid in clusters usually on ventral.
• Polyphagous in nature, major pest of tomato, distributed widely Moths are stout, pale to dark brown, fore wings greyish browns with wavy white markings, hind wings are opalescent, semi hyaline, white with dark brown marginal line.

Nature of damage

Freshly hatched larvae feed gregariously, scraping the leaves from ventral side, later disperse, feeding voraciously at night on the foliage. Larvae may also feed on fruits hollowing these out.

Control

Plant castor (50 / acre) as trap crop which attracts the egg laying moth. Collect and destroy egg masses and young larvae on skeletonised leaves both on trap crop castor and also tomato.

• Install pheromone traps (@ 4 / acre) to monitor the pest. Spray 5% NSKE to kill early stage larvae.
• Flood irrigation may be adopted to bring out hiding larvae.
• Grown up larvae can be managed with poison bait (10 kg bran + 1 kg jaggery + 1 It Monocrotophos or 1 kg Carbaryl + little water) distributed in the field near base of the plant.

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