English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Mefenoxam and fosetyl-Al are common fungicides used to supplement disease control of Pythium damping-off and root rot in forest nurseries of the western United States. However, it is unknown whether fungicide-resistant Pythium isolates are present or whether new fungicide and biological treatments might also provide supplemental disease control. Isolates of Pythium irregulare, P. sylvaticum, and P. ultimum from three forest nurseries were evaluated for in vitro sensitivity to mefenoxam and fosetyl-Al. A greenhouse study was also conducted to assess efficacy of fungicide and biological treatments in Douglas-fir (Pseudotsuga menziesii) seedlings inoculated with Pythium dissotocum, P. irregulare, and P. ‘vipa’. P. irregulare was approximately three times less sensitive to mefenoxam (0.20 μg/ml) than P. sylvaticum (0.06 μg/ml) and P. ultimum (0.06 μg/ml), and two resistant isolates of P. ultimum were identified (≥311 μg/ml). All three Pythium spp. were similarly sensitive to fosetyl-Al (1,256 to 1,508 μg/ml) and no resistant isolates were found. In the disease control efficacy trial, both fosetyl-Al and phosphorous acid consistently provided good protection against damping-off caused by P. dissotocum, P. irregulare, and P. ‘vipa’. Other treatments, including mefenoxam, also provided good or intermediate protection but efficacy depended upon which Pythium sp. was used. Growers should consider rotating mefenoxam use with other fungicide chemistries or biological treatments to prevent further development and spread of mefenoxam-resistant isolates.

plant disease

Sensitivity of <i>Pythium irregulare, P. sylvaticum</i>, and <i>P. ultimum</i> from Forest Nurseries to Mefenoxam and Fosetyl-Al, and Control of Pythium Damping-off

Sensitivity of Pythium irregulare, P. sylvaticum, and P. ultimum from Forest Nurseries to Mefenoxam and Fosetyl-Al, and Control of Pythium Damping-off