Downy Mildew - Plant Specific Mildews

Plant Specific Mildews

Hop Downy Mildew (caused by Pseudoperonospora humuli) is specific to hops (Humulus lupulus). The disease is the single most devastating disease in Western United States hopyards, since the microbe thrives in moist climates. Infected young hop bines become stunted with thickened clusters of pale curled leaves. These spikes have a silvery upper surface, while the undersides of leaves become blackened with spores. These dwarfed spikes are called "basal spikes". 'Lateral' or 'terminal' spikes occur further up the vine. An entire hop crop could be devastated in only a few days.

Similarly, cucurbit downy mildew (caused by Pseudoperonospora cubensis) is specific to cucurbits (e.g., cantaloupe (Cucumis melo), cucumber (Cucumis sativus), pumpkin, squash, watermelon (Citrullus lanatus) and other members of the Cucurbitaceae/gourd family). The disease is one of the most important diseases of cucurbits worldwide.

Read more about this topic:  Downy Mildew

Famous quotes containing the words plant and/or specific:

    “I please
    To plant some more dew-wet anemones
    That they may weep.”
    —Unknown. The Thousand and One Nights.

    AWP. Anthology of World Poetry, An. Mark Van Doren, ed. (Rev. and enl. Ed., 1936)

    “I recognize in [my readers] a specific form and individual property, which our predecessors called Pantagruelism, by means of which they never take anything the wrong way that they know to stem from good, honest and loyal hearts.”
    —François Rabelais (1494–1553)