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The pest
Damage
Fight
Protocol to
proceed

Helicoverpa armigera (Tomato fruitworm)

The pest

Tomato fruitworm larvae

Adults: nocturnal. The female is brown and the male greenish gray. The hind wings are whitish with a characteristic dark feature in the distal part. Adults are butterflies from 35 to 40 mm. wingspread. This specie may have 3-4 generations per year and it’s migratory.

Eggs: are laid isolated, preferably in the face of the terminal leaflets. White and spherical, are longitudinally grooved and measure 0.5 mm. of diameter. As they get older their color changes from white to dark brown.

Larvae: caterpillars, varying in color, with brownish or greenish yellow hues, show a dorsal dark green band along with other lighter bands and the presence of black hairs arising from the white circles. Their maximum length is about 30 to 40 mm, and it’s reached in about three weeks. Caterpillars migrate to young tomatoes, penetrating inside and consuming their interior. The time required for embryonic development varies with temperature, varying from 3 days between 25 and 35 º C up to 20 days at 13 ° C.

Pupae: larvae close to pupate stop feeding and begin to spin a cocoon buried in the ground. Pupate are fusiform, green after its formation but changing into slightly brown at the end of development. Its length ranges from 20 to 25 mm. When conditions are unfavourable there is a diapause stage.

Damage

It’s a polyphagous pest that has tomato and corn as principal hosts, followed by cotton, pepper, as well as legumes and ornamental plants, etc. It can complete the cycle on the natural vegetation. Larvae prefer feeding on the parts of the plant with high concentrations of nitrogen. On tomato, the fruits are the most affected part, but flowers, stems and leaves can also be damaged, resulting in optimal conditions for rot or attack of secondary pests. If larvae are big and the fruits are small one larva can attack some fruits per day.

Fight

Larva emerging from inside an infested tomato

DETECTION AND MONITORING:

Using a monitoring device by (card of Unitrap product) traps and pheromones with an insecticide, will allow to detect the presence of adults in each plot.

INSTRUCTIONS FOR MONITORING

Place 3 to 4 "Unitrap" traps per hectare or per monitored area. Place it over the crop for good ventilation, and put them up as the crop grows.
Place the pheromone into the basket and the insecticide into the receptacle of the trap. Always use protection gloves.
Traps are monitored 1 ve1 time per week , to collect and note down the number of insects captured and verify that traps are still in the correct position.
Attractants must be renewed every 6 weeks. .

While no catches are detected, there is no risk of damage . Once detected the first catches is advisable to make a visual estimation by direct sampling in the plants, observing the fruits, and other parts of the plant. Then it is recommended to contact with the technical staff of Pest Protection Service in the area, which will evaluate the situation on the ground and determine the measures to be taken in each case.

MASS TRAPING

To carry out the control of the pest, follow these instructions:

Place 8 to 10 "Unitrap" traps per hectare of crop, depending on the density of catches. Place them about 20 cm. over the crop, inside the plot, but also outside it, strengthening the areas with most catches, where the distance between traps will be of 25 meters.
Mass trapping will take place throughout all the development of the plant.
Mass trapping needs to be complemented with the phytosanitary treatments recommended by the technicians of Pest Protection Service.

PROTOCOL TO PROCEED

IN CASE OF ATTACK OR DETECTION OF TOMATO CROPS INFESTED BY TOMATO FRUITWORM

Do not make indiscriminate and aggressive treatments that may alter the biological balance of the crop area and its natural enemies.
Treat initially with certain Bacillus thuringiensis strains and with the specific products recommended by the technicians of Pest Protection Service.
Don’t abuse of specific products against this pest, as it would no longer be effective.
Inform and take benefit of Pest Protection Service technicians’ help, in order to make the most appropriate actions in your plots.
Note the predominant pest stage and the population level of each stage to which treatment is focused. If the use of phytosanitary is needed, with this information the most appropriated product will be choosing (ovicide, larvicide, adulticide).

PROPHYLACTIC MEASURES

Remove weeds and crop residues, as they can act as reservoirs of plague.
Do not abandon the crops at the end of the cycle. Do crop rotations. Remove and destroy the pruning.
In greenhouses, install a double door at the entrance, or a door plus a grid of equal density to the outer (minimum 10x20 yarn/cm2).
Do not remove the fruits or the affected parts of the plant without taking the appropriated actions to prevent pest dispersion. It’s advisable to destroy them.