Table 2.
Confirmation of R and S phenotypes to the herbicide Atlantis (active ingredients mesosulfuron + iodosulfuron).
| Comparison | ED50, g ha-1 (SE) | RI | t-value | P-value |
|---|---|---|---|---|
| Biomass | ||||
| Baseline | 717.2 (148.1) | 11.7 | 4.469 | <0.001∗∗∗ |
| R | 1302.2 (267.9) | 21.3 | 4.660 | <0.001∗∗∗ |
| S | 61.2 (9.1) | – | – | – |
| Survival | ||||
| Baseline | 1600.0 (327.4) | 12.4 | 7.460 | <0.001∗∗∗ |
| R | 2619.6 (333.3) | 20.3 | 4.485 | <0.001∗∗∗ |
| S | 129.1 (18.3) | – | – | – |
Aboveground dry-weight data (biomass) was analyzed using a three-parameter log-logistic regression model, while plant survival was analyzed using a binomial two-parameter model. The Resistance Index (RI) has been calculated for the Baseline and resistant (R) seed populations relative to the susceptible (S) seed population, as the fold-difference between the compared ED50 values. Significance (t- and P-values) shown are results of post hoc pairwise comparison of ED50 values for the Baseline and R populations relative to the ED50 of the S population using a Z-test (asterisks denote significance at: ∗∗∗P ≤ 0.001).