Table 3. Counts and mean weight per site of Osmia cornifrons that tested positive (+) or negative (-) based on PCR screens for Ascosphaera (Asc), Aspergillus (Asp), Paenibacillus (Pae), and multiple microbes (mul).
| Site code | # inds tested | % - | % Asc+ | % Asp+ | % Pae+ | % mul+ | mean weight (mg) a | mean weight - (mg) | mean weight + (mg) |
|---|---|---|---|---|---|---|---|---|---|
| Females | |||||||||
| RNV | 10 | 60.0 | 10.0 | 30.0 | 0 | 0 | 52.7 | 49.4 | 57.7 |
| OHG | 33 | 30.3 | 51.5 | 48.5 | 12.1 | 39.4 | 49.2 | 45.9 | 50.6 |
| OWH | 28 | 82.1 | 10.7 | 7.1 | 0 | 0 | 59.5 | 58.3 | 64.7 |
| CCL | 16 | 75.0 | 18.8 | 12.5 | 0 | 6.3 | 41.0 | 43.6 | 33.2 |
| CIC | 18 | 50.0 | 22.2 | 38.9 | 0 | 11.1 | 48.5 | 54.7 | 42.3* |
| CCI | 2 | 50.0 | 50.0 | 0 | 0 | 0 | 37.3 | 34.0 | 40.5 |
| Mean | 17.8 | 57.9 | 27.2 | 22.8 | 2.0 | 56.8 | 48.0 | 47.7 | 48.1 |
| Males | |||||||||
| RNV | 28 | 28.6 | 57.1 | 42.9 | 3.6 | 28.6 | 30.3 | 31.8 | 29.7 |
| OHG | 66 | 15.2 | 62.1 | 72.7 | 7.6 | 54.5 | 35.2 | 35.4 | 35.2* |
| OWH | 42 | 54.8 | 33.3 | 19.0 | 0 | 7.1 | 36.5 | 37.1 | 35.9 |
| CCL | 30 | 50.0 | 20.0 | 43.3 | 0 | 13.3 | 32.3 | 35.9 | 28.6 |
| CIC | 20 | 50.0 | 25.0 | 40.0 | 0 | 15.0 | 33.9 | 37.6 | 30.2 |
| CCI | 7 | 28.6 | 71.4 | 14.3 | 0 | 14.3 | 23.5 | 26.3 | 22.4 |
| Mean | 32.1 | 37.9 | 44.8 | 38.7 | 1.9 | 22.1 | 32.0 | 34.0 | 30.3* |
| Dead larvae/adults | |||||||||
| RNV | 4 | 100 | 0 | 0 | 0 | 0 | NA | NA | NA |
| OHG | 9 | 33.3 | 55.6 | 55.6 | 0 | 44.4 | NA | NA | NA |
| OWH | 6 | 16.7 | 83.3 | 33.3 | 0 | 33.3 | NA | NA | NA |
| CCL | 4 | 100 | 0 | 0 | 0 | 0 | NA | NA | NA |
| CIC | 1 | 0 | 100 | 100 | 0 | 100 | NA | NA | NA |
| CCI | 2 | 0 | 100 | 50 | 100 | 100 | NA | NA | NA |
| Mean | 4.3 | 41.7 | 56.5 | 39.8 | 8.3 | 46.3 | NA | NA | NA |
a Mean values of the weight in milligrams (mg) of live bees that were then screened for the presence of microbes (mean weight), of only those bees testing negative (mean weight -), and of only those bees testing positive for one or more microorganism(s) (mean weight +).
* Mean weight of bees testing positive versus negative were significantly different based on a Welch's t-test at p < 0.05.