Acetolysis modifications to process small pollen samples swabbed from live bees.

Understanding the resources bees use is essential because we depend greatly on their ecosystem services, and this information could help guide conservation efforts. One way to identify the flowers that bees visit is to collect pollen directly from the bee and then identify the pollen with plant taxa. However, the current method for processing such pollen samples, acetolysis, is designed for samples such as those collected across individuals (e.g., pollen trap), bee nests, or, at the very least, from pollen pellets collected from live bees or from the exhaustive removal of pollen from lethally collected individuals. Smaller samples, including those down to just a few pollen grains sampled from live bees, could facilitate additional opportunities for bee-pollen research, if they can be processed effectively. We present a revised acetolysis methodology designed specifically for processing small pollen samples, so that they can then be used for more accurate identification. Using pollen samples from cotton swabs directly applied to live bees in the field, we demonstrate the effectiveness of our methodology for processing small pollen samples, including samples too small to be visually detected. This methodology can permit nonlethal collections in the field from a greater number of bee species.

Identification of sex-specific markers based on gene expression in adult Colorado potato beetles.

The Colorado potato beetle, Leptinotarsa decemlineata, (Coleoptera: Chrysomelidae) is an economically important pest insect of potatoes. Understanding how the mechanisms driving its invasiveness vary between sexes will be critical for developing modern control methods. However, the currently available methods for sexing adult Colorado potato beetles are either inefficient or unsuitable for projects that require RNA as an input, like those measuring gene expression. Therefore, the development of simple molecular tools that are tailored to these studies is important. In this study, we used publicly available RNA-seq data to select 5 candidate genes for sex-specific markers in adult Colorado potato beetles. We confirmed that our 5 marker candidates exhibit a sex-specific expression pattern and can be used as PCR markers for sex determination. This method of sex detection will allow researchers to distinguish the sex of the individual with a simple PCR reaction using cDNA as the template and assign sex to RNA-seq samples post hoc.