Open AccessSensitivity of Fusarium oxysporum f. sp. niveum to Prothioconazole and Pydiflumetofen In Vitro and Efficacy for Fusarium Wilt Management in Watermelon
Author(s) -
Nathan Miller,
Jeffrey R. Standish,
Lina M. QuesadaOcampo
Publication year - 2020
Publication title -
plant health progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.565
H-Index - 9
ISSN - 1535-1025
DOI - 10.1094/php-08-19-0056-rs
Subject(s) - citrullus lanatus , fusarium wilt , fusarium oxysporum , biology , fungicide , horticulture , fusarium , agronomy
Field experiments were conducted in 2015 and 2016 to determine the effects of drench or drench-plus-foliar applications of prothioconazole and pydiflumetofen on Fusarium wilt (caused by Fusarium oxysporum f. sp. niveum; FON) of watermelon (Citrullus lanatus var. lanatus). In both years, all fungicide treatments reduced final disease incidence, final severity, and area under the disease progress curve, regardless of application rate or method. Yield data were collected in 2016, and both number and weight of marketable fruit were greatest in plots treated with pydiflumetofen as a drench-plus-foliar application at either application rate. Additional experiments were conducted to characterize sensitivity distributions of 48 isolates of FON from North Carolina to prothioconazole and pydiflumetofen. Mean prothioconazole EC 50 values ranged from 0.10 to 0.55 µg/ml, and mean pydiflumetofen EC 50 values ranged from 0.34 to 1.88 µg/ml. The results presented here validate pydiflumetofen as an effective management option for Fusarium wilt of watermelon, confirm previously observed efficacy of prothioconazole, and provide current evidence of pathogen sensitivity to these fungicides in North Carolina.