21. And check for diseases and insects, such as powdery mildew , whiteflies and aphids. 22. A powdery mildew disease of hops has sometimes been erroneously called blue mold. 23. _Powdery mildew : This is a powdery white substance on foliage and stems. 24. The loose bunches help to prevent Bunch rot, Powdery mildew and Downy mildew. 25. It is used to control almost all fungal diseases of plants except powdery mildews . 26. The main goal, however, has been disease resistance, especially to powdery mildew , not hardiness. 27. The prime fungicide used to control powdery mildew is myclobutanil. 28. Uncontrolled powdery mildew rots the grapes from the inside out. 29. To limit powdery mildew resistance, growers alternate treatments by employing multiple modes of action. 30. Pots crowded together can trap air and humidity, providing ideal conditions for powdery mildew .
