ECONEX SPODOPTERA EXIGUA 2 MG 40 DAYS

Sexual pheromone diffuser of the species Spodoptera exigua to attract males, with a duration of 40 days in normal field conditions.

Diffuser of natural rubber in capsule-shape. It is packaged individually in an aluminium sachet with labelled instructions. Once taken out of the sachet, the diffuser does not need any activation operation. Simply place it directly in the trap

Spodoptera exigua is a polyphagous insect which attacks several crops and random plants.  It is present in high numbers in parts of southern Spain. 

It is a migratory species and therefore has several flights.  It spends the winter in the southern Iberian peninsula or North Africa and often travels to the north when summer is approaching.

It is found across Africa, southern Europe, Asia, Japan, Australia, the United States and Canada.

MORPHOLOGY AND BIOLOGY

Egg: They are usually found in small groups (10-250 eggs), coated with white flakes and are called ooplacas or plastones. Each egg can range in colour from white to yellowish-brown when just laid, to dark brown before hatching.  They also have vertical striations and are dome-shaped.  Average egg size ranges from 0.35 to 0.37mm.

Larva: It is of variable colour, usually green but can also be brown depending on its food and whether they are grouped (darker) or isolated. In the early stages the larvae are white with a black head.

The larvae of the last stages have an ochre-coloured head with a whitish reticulated body.  They have lines and spots along the body.  It has 3 pairs of legs, 5 pairs of thoracic legs and 5 false abdominal legs.  They typically pass through five stages. Newly-hatched its size is 1 mm and it can reach 30 to 40 mm when fully developed.

Pupa: Initially green in colour, later turning brown. It has four hooks on its underside which hold the adult once it has emerged from the chrysalis. The average size of the pupae is 20 mm.

Adult: It has a wing span of 2.5 to 3 cm.  The front wings are earthy brown or grey.  It has two characteristic orange orbicular and renal spots which stand out from the rest of the body.  The rear wings are white with darker lines.  The edges of the wings are blackish.

SOURCE: Agricultural Council of Andalusia (Spain)

DETECTION AND MONITORING

For detection and monitoring 1 trap should be set per hectare placed at crop level. Traps can be placed on a hanger for this purpose and should be set in spring.

MASS TRAPPING

Mostly the males of this species are captured, in order to reduce the mating, so that non-copulated females will have unviable eggs. This reduces the pest population.

To carry out mass trapping the number of traps per area should be increased depending on the location and homogeneity of the crops. One trap can control an area of between 500 and 1,000 m². This entails a trap density of 10 to 20 traps per hectare.

NECESSARY MATERIAL

An ECONEX POLILLERO or EOSTRAP^® trap, and a pheromone diffuser ECONEX SPODOPTERA EXIGUA as attractant.

PERIOD OF USE

To achieve good control of the Spodoptera exigua, it is advisable to combine the two methods: detection and monitoring and mass trapping. In spring you can place 1 to 2 traps per hectare to detect the pest and observe the level of their populations.

Through established thresholds of tolerance in each area, the control measures are later defined, in this case mass trapping. The threshold of tolerance for Spodoptera exigua is very low and varies according to the area. Generally it is around 3 captures per trap and per week. Moment in which we recommend to set traps all over the crop for mass trapping.

DAMAGES

DIRECT DAMAGE:  The larvae in the first stages show gregarious behaviour. They gnaw at the parenchyma of the underside of the leaves, leaving the epidermis.  In the following larval stages they distance and isolate themselves, devouring the leaves completely, which causes severe defoliation.  They can also gnaw at the stems and perforate the galleries.  In severe attacks fruit damage can be observed.

INDIRECT DAMAGES: The wounds caused by this plague facilitate the entry of other pathogens (fungi, bacteria, etc.)

FACTORS THAT INFLUENCE THE NUMBER OF TRAPS REQUIRED

Pest population, adjoining crops, level of control required, etc.

An important factor is crop size. In small and irregular sized crops a greater number of traps will be needed. Another important factor is the distance between crops with the same pest. In such cases the crop boundaries should be reinforced, so a trap density of about 20 traps per hectare may be needed.  More traps may be needed in the case of mass trappings.

RESULTS

If technicians or farmers use the traps and pheromones as described here and when the first generation of adults emerges, then the effectiveness of this control system is very good, with a very low level of damage. When large crop areas are covered, more than 95% of the pest is often controlled.

A factor limiting this system is where there are small farms surrounded by other plots with a high level of infestation of this pest.   Apart from some important basic rules in controlling Spodoptera exigua effectively, each farmer/technician should find his/her own system of achieving this and he/she may experiment with this system, even establishing his/her own tolerance thresholds.

STORAGE OF THE DIFFUSERS

The diffusers must be kept in their original container and in a refrigerator at 4^oC, or in the freezer at -18^oC, in which case they will remain valid for 2 and 4 years respectively.