Maximizing the hatchability of Locusta migratoria (Orthoptera: Acrididae) eggs under artificial hatching conditions

Locusta migratoria is a potential alternative food and animal feed additive in South Korea and has already been registered in the European Union. We investigated the optimal conditions to improve hatchability of L. migratoria eggs under varying hatching conditions for improved artificial rearing. The parameters such as temperature, photoperiod, illuminance, or relative humidity were altered, while the other factors were kept constant. Among the four different temperature treatments (25, 27, 30, and 33 degrees C), the 33 degrees C temperature showed the highest total hatching rate of 85.6% at days 8-12 after oviposition. For photoperiod, hatchability was the highest (81.2%) at 9 L/15D, followed by 80.0% at 12 L/12D, and 72.6% at 15 L/9D. Under illuminance conditions of 600, 1,800, and 3,500 lux, 3,500 lux displayed the highest total hatching rate of 76.1% at days 7-11 after oviposition. Among the relative humidity (RH) levels of 50%, 65%, and 80%, 65% RH provided the highest hatching rate of 86.4% at days 8-13 post-oviposition. In short, the most effective conditions for hatchability were 33 degrees C, 9 L/15D, 65% RH, and 3,500 lux. Under these conditions, the hatching rate increased significantly to 98.8%. Application of these conditions will contribute to improve hatchability, which will be necessary for industrialization of L. migratoria.