Fungal species that cause powdery mildew in greenhouse-grown cucumber and melon in Paraná State, Brazil
No hay miniatura disponible
Fecha
Título de la revista
ISSN de la revista
Título del volumen
Editor
Universidade Estadual de Maringá
Resumen
Descripción
The powdery mildew caused by Oidium spp. is an important disease for several crops of the Cucurbitaceae family. Although the teleomorphs, Podosphaera xanthii and Golovinomyces cichoracearum , currently have already been described as the ca usal agents of powdery mildew in Brazil, only P. xanthii is considered the main causal agent of powdery mildew fi eld epidemics. The objective of this work was to identify and determine the prevalence of the species causing powdery mildew in cucumber ( Cucumis sativus ) and melon ( Cucumis melo var. reticulatus ) grown in greenhouses in the St ate of Paraná in Brazil. The morphological traits of the conidial stages, such as th e presence of fibrosin bodies and a germinative tube, were used to identify the species. Leaves exhibiting high severity of powdery m ildew were collected from plants of 13 plastic greenh ouses during different seasons in 2003/ 2004 and in different regions of Paraná State. In all environments, a significant prevalence of P. xanthii (80-100%) was observed affecting parthenocarpic or ordinary cucumber and melon. Golovinomyces cichoracearum was observed in six greenhouses, with up to 20% of conidi a of this species on the samples.
Palabras clave
Agrociencias