NEW PAPER OUT! Thermal tolerance of western corn rootworm: Critical thermal limits, knock-down resistance, and chill coma recovery

4th pub for 2022 just came out in Journal of Thermal Biology! This work is the first paper from USDA and contains ideas that I have been wanting for test for years. We measured how ramping rate, starting temperature, genetic line, and sex affected critical thermal limits. We then expanded these ideas to look at knock-down resistance and chill coma recovery. Overall, we found striking similarities between genetic line and sex across most of the physiological assays. But there were some surprising results. Our abstract sums up our results nicely…

Western corn rootworm, Diabrotica virgifera virgifera, is one of the most economically important crop pests in the world with estimates of damage and control approximating over $1 billion USD annually. Despite an abundance of research devoted to studying rootworm biology in the central Corn Belt of the United States, key aspects on their thermal ecology are still lacking. Here we address this knowledge gap by measuring critical thermal limits, knock-down resistance, and chill coma recovery. In doing so, we also address methodological questions surrounding measurements of thermal tolerance using a variety of dynamic and static assays. The average critical thermal maxima across all trials was 43.0 °C, while the average critical thermal minima was 2.5 °C. Critical thermal limits were relatively invariant across all treatments except at faster ramping rates. Knock-down resistance decreased with increasing temperature as survival dropped from 100% at 39 °C to 0% within 10 min at 44 °C. Recovery from chill coma increased by 1.62 min for each hour of exposure at 0 °C, while survival decreased by 50% after only 24 h. Combined, our results present the first composite picture of different thermal traits for western corn rootworm, which will be vital for predicting their survival and potential spread under future climate change scenarios.

You can find the full manuscript by [CLICKING HERE]. More rootworm thermal papers are on the way!