Plant Disease (2017) 101, 1139-1144
Lei-ming He, Kai-di Cui, Di-cheng Ma, Rui-ping Shen, Xue-ping Huang, Jian-gong Jiang, Wei Mu and Feng Liu (2017)
Activity, translocation, and persistence of isopyrazam for controlling cucumber powdery mildew
Plant Disease 101 (7), 1139-1144
Abstract: A cotyledon bioassay was conducted to assess the activity of isopyrazam against Podosphaera xanthii (Castagne) U. Braun and N. Shishkoff, causal agent of cucumber powdery mildew. Results showed that isopyrazam has protective and curative activity against P. xanthii, with EC50 values of 0.04 and 0.05 mg liter–1, respectively. These activities are higher than those for hexaconazole, difenoconazole, pyraclostrobin, kresoxim-methyl, and azoxystrobin, fungicides currently used against cucumber powdery mildew. Isopyrazam at 0.5 mg liter–1 damaged conidiophores. Results of inoculation tests in greenhouse pots indicate that isopyrazam demonstrates a level of systemic movement in cucumber plants, especially regarding translaminar and transverse translocation. Efficacy following translaminar and transverse translocations on cotyledons and leaves treated with 60 mg liter–1 was 94.40% and 88.96%, and 95.26% and 82.83%, respectively. In addition, isopyrazam at 60 mg liter–1 exhibited a long duration of efficacy against cucumber powdery mildew, almost 2 to 3 weeks longer than that of triazoles and strobilurins. Similar trends in residual durations were observed during 2014 and 2015 greenhouse trials. Isopyrazam at 30 and 60 a.i. g ha–1 provided efficacy ranging from 83.27 to 90.83% 20 days following treatment. In conclusion, isopyrazam has translaminar and transverse translocation in cucumber leaves, and long duration of activity against cucumber powdery mildew.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Research topic(s) for pests/diseases/weeds:
control - general
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Podosphaera xanthii | Cucumber (Cucumis sativus) |
