Biological Control of Powdery Mildews of Greenhouse Ornamentals 1998
Project Leaders: Greg English-Loeb, David Gadoury, Andrew Norton
1. Determine the ability of Orthotydeus lambi to control mildew infection in rose and poinsettia growing in the greenhouse, and compare the level of protection obtained with that of a conventional fungicide program.
2. Evaluate growth rates and persistence of O. lambi population on these two crops.
Due to discouraging results with the poinsettia trial, efforts were concentrated on control of rose powdery mildew. The mycophagous mite Orthotydeus lambi occurs naturally on wild and cultivated roses in upstate New York, so mite establishment should be easier on roses than on poinsettias. To date, we have planted mature rose plants (cv 'Tropicana') in the greenhouse and established colonies of rose powdery mildew and O. lambi for use in the experiment. Because the dormant rose plants needed for this experiment were not available until six weeks ago (November 1), no further developments can be reported at this time.