Effect of nutritional stress and larval crowding on survival, development and reproductive output of Mediterranean flour moth, Ephestia kuehniella Zeller

Abstract

Eggs of the Mediterranean flour moth (MFM) are widely used for rearing biocontrol agents. Understanding how nutritional stress and larval crowding affect MFM fitness is essential to the development of an optimal production programme. Such knowledge could also help lead to novel management strategies because it is an important storage pest. The development, survival and reproductive output of MFM under five densities (50, 100, 200, 400 and 800 larvae reared on 50 g of diet) were examined. As larval density increased the larval developmental period significantly increased from 27.8 to 33.7 days, and the larval survival rate and resulting females' fecundity significantly decreased from 77.6 to 47.6% and 326.8 to 132.6 eggs, respectively (P<0.0001). There was no significant difference in fertility, survival, pupation and emergence rates between densities of 50, 100 and 200 larvae. Therefore, the optimal rearing density could be up to 200 larvae on 50 g of diet. © 2012 New Zealand Plant Protection Society (Inc.).