Application of high hydrostatic pressure has been proposed as an alternative quarantine process for the Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), one of the most important insects infesting mangoes, citrus fruits, and other fruits in Mexico and other Latin American countries. The present study was performed to determine the effect of high pressure treatments at 0 degrees C on the survivorship of eggs and larvae of this pest. The effect of time and pressure level at near-freezing temperatures on the egg hatch and survival of larvae is discussed. Eggs and larvae were pressurized at 25, 50, 75, 100, or 150 MPa for 0, 5, 10, or 20 min at 0 degrees C. Hatch was recorded for 1-, 2-, 3-, and 4-day-old pressurized eggs. For pressurized larvae (first, second, and third instars), percentage of survival was registered. Further, third instars were studied for their ability to pupate and develop to adulthood. The results showed that eggs had higher resistance than larvae to pressure. Larvae were not able to resist pressure treatments at 75 MPa for 20 min at 0 degrees C. Treatments at 150 MPa for 20 min at 0 degrees C were needed to destroy all eggs and larvae of A. ludens, indicating that this process might be useful as a quarantine method for infested fruits. However, more studies involving combination of high hydrostatic pressure at low temperature with precooling treatments are needed in order to decrease the pressure level to avoid fruit damage.

The Mexican fruit fly Anastrepha ludens Loew (Diptera: Tephritidae) is one of the most important insects infesting mangoes, citrus, and other fruits in Mexico and other Latin-American countries. Quarantine methods approved to destroy this insect decrease the shelf life of commodities. The objective of this study was to determine the effect of high-pressure processing using an initial temperature of 50 degrees C on the survivorship of eggs and larvae of the Mexican fruit fly. Eggs and larvae were pressurized at 25, 50, 75, 100, or 150 MPa for 0, 5, 10, or 20 min. The hatching ability of pressurized eggs of 1, 2, 3, and 4 days old and survivorship of the first, second, and third instars were registered. Further, the ability to pupate was studied in surviving third instars. The results showed that eggs were more resistant than larvae to the high-pressure processing. Treatments at 150 MPa at initial 50 degrees C for 10 min destroyed all eggs and larvae of A. ludens, indicating that this process might be useful as a quarantine method for infested mangoes or other fruits.

High-pressure processing (HPP) has been proposed as an alternative quarantine method against the Mexican fruit fly Anastrepha ludens Loew (Diptera: Tephritidae), which is one of the most important pests infesting mangoes, citrus, and other fruits in Mexico and other Latin-American countries. However, processing conditions used to destroy eggs and larvae also affect the shelf life of fruits. The objective of this study was to assess the biological viability of A. ludens eggs treated with HPP, establishing whether undestroyed eggs were able to develop larvae, pupae, and adults capable of reproduction. Eggs of 1, 2, 3, and 4 days old were pressurized at 50, 75, or 100 MPa for 0, 5, 10, or 20 min. The hatching ability of pressurized eggs; survivorship of third instars, pupae, and adults emerged; and their capability to produce viable eggs were examined. The results showed that the hatching capacity of eggs and the larval development were affected negatively by the treatment duration and level of pressure. Treatments with 100 MPa for 20 min inhibited the hatching capacity of eggs of 2, 3, or 4 days old by 100%, but the inhibition was of 99.8% for 1-day-old eggs. Most of the eggs that survived the treatments were able to produce adults that can reproduce. The percent of hatching of eggs of A. ludens oviposited for adults obtained from pressurized 1-day-old eggs treated with 100 MPa for 20 min was 64.81%. Thus, more efforts must be addressed to destroy eggs and larvae during HPP because surviving organisms can reach adult stage and reproduce.