Constant and variable heat shock effects on Galleria mellonella L. (Lepidoptera: Pyralidae) mortality and biological traits in the context of climate change

Abstract

One of the most significant global challenges is the rising temperatures attributed to climate change and the increasing presence of pest insects. The changes in the biological characteristics of invasive and harmful insect species due to continuously rising temperatures endanger various ecosystems, especially agriculture. The effects of different heat shocks (constant and variable) on the life history traits and mortality rates of the greater wax moth Galleria mellonella L. (Lepidoptera: Pyralidae) were examined to better understand the lethality and physiological impacts of global warming. The research indicates that higher temperatures lead to a shorter life span and as the exposure to constant temperature increases, the mortality rate of insects rises. For G. mellonella subjected to constant heat shock, LTemp50,99 was determined as 42.645 and 45.137 °C. In constant heat shock, the larval spinning was prolonged, pupal time, pupal period, and adult emergence time were shortened. Under this heat shock, matured individuals’ weights remained largely unaltered besides longevity and fecundity of the adult population reducing. In variable heat shock, while the larval spinning and pupal period were unaffected, pupal time and adult emergence time were shortened. Additionally, adult’s weights maturing under variable heat shock was unaffected besides longevity significantly shortening and fecundity fluctuating. This study predominantly addresses the interplay between elevated temperatures and harmful insects, depending on the type of heat shock exposure, highlighting the consequences of climate change and global warming on physiological attributes and mortality patterns within G. mellonella.