Powdery mildew of cucurbitsis an annual problem in Iowa and in some years has the potential to ruin the crop.Control can be difficult when weather is favorable for disease development and has traditionally relied on the application of fungicides. Fortunately, the introduction of powdery mildew resistant squash cultivars has provided a more efficient approach to managing this disease and producing a high-quality crop. This trial was initiated in 2005 and continued in 2006 to provide powdery mildew resistant (PMR) cultivar information to squash growers to guide cultivar selection.