Table 1.
Summary of pilot field study to evaluate stability of topically applied dsRNA on soybean plants using the QuantiGene assay.
| Treatment | Application rates (target) and timing | Spray rate (liters per hectare) | Carrier | Sampling | Residue level average concentration4 ng/g fw (min.–max.) |
|---|---|---|---|---|---|
| 1 (Control, 1 plot) | Untreated | 187 | Ultrapure water plus Silwet L-77 at 0.5% v/v | 12 whole plants; plus 1 kg grain at maturity | N/A |
| 2 (2 replicate plots) | 59.3 g ai/ha1 at three separate applications: V4/R1, V10/R3, and 7 days before harvest | 187 | 12 whole plants per plot collected and pooled for analysis at 0,3, and 7 DAT2; plus 1 kg grain at maturity | 0 DAT2: 4166 (4158-4174) 3 DAT2: 242 (235-249) 7 DAT2: 66.23 (56.01-76.44) Seeds: 0.19 (0.15-0.23) | |
| 3 (2 replicate plots) | 59.3 g ai/ha1 at two separate applications: V4/R1, and V10/R3 | 187 | 12 whole plants per plot collected and pooled for analysis at 0,3, and 7 DAT3; plus 1 kg grain at maturity | 0 DAT3: 1317 (1014-1619) 3 DAT3: 50.33 (50.17-50.49) 7 DAT3: 25.66 (25.47-25.85) Grain: Not Detected (< LOD) |
1For treatment 2 actual applied rates were 54.9–63.9 g ai/ha. For treatment 3 actual applied rates were 57.2–59.4 g ai/ha.
2Days after treatment (DAT) refers to time point following initial application at V4/R1.
3Days after treatment (DAT) refers to time point following second application at V10/R3.
4The average residue concentration was calculated at each sampling interval for two replicate plots for treatments 2 and 3. dsRNA concentrations for each replicate plot provided in parenthesis.
Assay’s LOD, 0.0015 ng/g fw; Assay’s LOQ, 0.0180 ng/g fw; fw, fresh weight; N/A, not applicable.