Assessment of Powdery Mildew Control Measures During the 1997 Hop Growing Season

A. Reeves. Presented at the MBAA 111th Anniversary Convention, Minneapolis, Minnesota, September, 1998.

Abstract
Hop Powdery Mildew was discovered in Yakima Valley hop yards in June of 1997. Because growers of the valley were unprepared for such a virulent, disease, it proved to be quite devastating. By year's, end numerous acres were either cut down pre-harvest, realized a decrease in yield, or a loss of quality. Powdery Mildew is again present in hop yards in the Yakima Valley in 1998. Nearly all the varieties grown in Washington have shown some disease. Unlike last year, the growers are better prepared and informed, and have at their disposal a wide range of tools from which to fight the disease. Washington growers are diligently pursuing a practical means from which to control powdery mildew. Numerous cultural as well as chemical control measures are being employed in combination with ine another. Some of these control measures will no doubt prove to -e more effective than others. By year's end we will have compiled .in analysis of the responses of the mildew to each type of treatment.
Keywords: hops, powdery mildew, fungicides, control techniques  

Sintesis
El moho blanco polvoriento del lupulo fue descubierto en los campos de cultivo del valle de Yakima en Junio de 1997. Porque los agricultores del valle no estaban preparados contra una enfermedad virulenta as�, esta resulto ser bastante devastadora. Hasta fines del a�o muchos acres fueron ya sea cortados, precosechados, tuvieron reducciones de producci�n, o una perdida de calidad. Esta enfermedad esta nuevamente presente en los cultivos de lupulo en el valle de Yakima en 1998. Casi todas las variedades cultivadas en el estado de Washington tienen algun tipo de enfermedad. Al contrario del a�o pasado, los agricultores estan mejor preparados e informados, y tienen a su disposicion una gama mas amplia de herramientas con las cuales combatir la enfermedad. Los agricultores del estado de Washington estan diligentemente siguiendo una serie de vias practicas para controlar la enfermedad. Numerosos metodos de control culturales as� como quimicos estan siendo empleados en combinacion entre si. Algunos de estos metodos de control sin duda seran mas efectivos que otros. Hasta fines del a�o habremos compilado un an�lisis del moho a cada tipo de tratamiento.