OCCURRENCE AND CONTROL OF BENZIMIDAZOLE AND DICARBOXIMIDE RESISTANT BOTRYTIS SPP. ON BULB CROPS IN WESTERN WASHINGTON AND OREGON

Gary A. Chastagner, K. Riley
In 1986, isolates of B. elliptica resistant to benomyl and iprodione were obtained from greenhouse-grown Asiatic lilies where applications of these fungicides failed to control disease development. To determine the prevalence of fungicide resistant Botrytis spp., samples were collected from field and greenhouse bulb crops in western Washington and the Willamette Valley of Oregon. Forty-three and 87.3% of the B. elliptica and 8.3 and 59.3% of the B. cinerea isolates obtained from fields and greenhouses, respectively, had multiple resistance to both benomyl and iprodione. Fourteen and 100% of the B. tulipae isolates obtained from field and greenhouse tulips, respectively, were resistant to benomyl; none were resistant to iprodione. Applications of anilazine, captafol, chlorothalonil, diniconazole, ferbam, mancozeb, triforine, zineb and a mixture of thiophane methyl and mancozeb effectively controlled resistant strains of B. elliptica on field-grown lilies.
Chastagner, Gary A. and Riley, K. (1990). OCCURRENCE AND CONTROL OF BENZIMIDAZOLE AND DICARBOXIMIDE RESISTANT BOTRYTIS SPP. ON BULB CROPS IN WESTERN WASHINGTON AND OREGON. Acta Hortic. 266, 437-446
DOI: 10.17660/ActaHortic.1990.266.59
https://doi.org/10.17660/ActaHortic.1990.266.59

Acta Horticulturae