Inheritance of powdery mildew disease resistance and association of micromorphological characters with disease resistance in flowering dogwood
Flowering dogwood (Cornus florida L.) is an economically important ornamental tree which accounts for 30 million dollars in total sales of which 23.2 % is from Tennessee nurseries. Powdery mildew is one of the devastating diseases in nursery productions of flowering dogwoods across the southern U.S. Although effective fungicides for controlling dogwood powdery mildew have been identified, frequent applications are required season long. This has increased production costs and forced small nursery growers out of business. Host resistance is the best method for controlling this disease, but only a few cultivars have shown resistance to powdery mildew resistance. While efforts to breed for resistance are being taken, identification of inheritance of resistance from parents to progeny is important to facilitate breeding strategies. 'Cherokee Brave' and selections R 14 and M19 have exhibited resistance at multiple locations, but the resistance mechanism is not known. The objectives of this study are to better understand mechanism of powdery mildew resistance inheritance. Finding out the markers associated with the disease resistance and checking the association of micro morphological characters association with resistance. Results from this study suggested that the powdery mildew disease resistance is inherited quantitatively and more than one gene is responsible for the resistance. There are few markers possibly polymorphic to disease resistance. Pubescence is very strong and positively associated with the disease resistance where stomatal density has no correlation.
Agriculture|Plant sciences|Plant Pathology
"Inheritance of powdery mildew disease resistance and association of micromorphological characters with disease resistance in flowering dogwood"
ETD Collection for Tennessee State University.