Table 1.
Effects of DAPG and other phloroglucinol derivatives on the release of Plasmopara viticola zoospores
| Compound | Dose (μg/ml) | Relative percent of released zoospores (% ±SE)a and their behaviors | |
|---|---|---|---|
| Zoospores | Behaviors or fate of released zoospores | ||
| PG | 50 | 98 ± 3 | Normal swimming |
| 100 | 62 ± 7 | Normal swimming | |
| 150 | 52 ± 9 | Swam at lower than normal speed | |
| 200 | 39 ± 10 | Swam at lower speed and 30% zoospores encysted | |
| MAPG | 15 | 98 ± 3 | Almost normal speed of swimming |
| 25 | 52 ± 9 | Swam at lower than normal speed | |
| 50 | 15 ± 4 | 53% of released zoospores encysted or burst | |
| 100 | 0 ± 0 | – | |
| DAPG | 5 | 98 ± 1 | Swam slowly in tight circle or jerky and 32% encysted |
| 10 | 70 ± 8 | Few zoospores (2%) were motile and others encysted and burst | |
| 15 | 3 ± 1 | All encysted and burst | |
| 25 | 0 ± 0 | – | |
| TAPG | 1 | 95 ± 5 | Swam very slow with turning and 40% zoospores encysted |
| 5 | 69 ± 6 | Few (20%) swam with low speed and others encysted or burst | |
| 10 | 31 ± 7 | Few (4–5%) swam with very slowly and others encysted and burst | |
| 15 | 15 ± 3 | All zoospores encysted and burst | |
| 25 | 0 ± 0 | – | |
| DPPG | 0.5 | 94 ± 4 | Normal swimming |
| 1.0 | 81 ± 7 | Only 40% swam in slower speed and rests encysted, few (10%) burst | |
| 1.5 | 46 ± 9 | Very few (8%) swam, and others encysted and/or burst (50%) | |
| 2.0 | 26 ± 5 | Only 1–2% swam and others encysted and burst | |
| 3.0 | 0 ± 0 | – | |
PG phloroglucinol, MAPG monoacetylphloroglucinol, DAPG diacetylphloroglucinol, TAPG triacetylphloroglucinol, DPPG dipropylphloroglucinol
aData presented here are average value ± SE of at least three replications in each dose of compound