Cause Eola rasp leaf (also known as Peach yellow bud mosaic or the yellow bud mosaic strain of Tomato ringspot virus) is vectored by the dagger nematode. The disease has been found on 'Royal Ann' in the Willamette Valley, 'Rainer' in The Dalles and on 'Bing' in Hood River and The Dalles. Mahaleb or Mazzard rootstock can become infected. Peach and almond also show symptoms while apricot is not seriously damaged (but can still be a reservoir of this virus strain). Many weeds can also be hosts of the virus. Disease spread in the orchard has been slow. Trees become unproductive.
Symptoms Declining trees have a bare-limb appearance that starts in the lower portion of the tree and moves upward, year after year, as spurs twigs and small branches die. Many shoots on affected limbs have a rosetted appearance. Spur leaves are small with prominent, whitish secondary veins that branch off from the midrib at right angles. Enations (small epidermal outgrowths) develop on the underside of these leaves adjacent to the midrib. In contrast to rasp leaf disease, enations are smaller and fewer and caused less leaf distortion. Along with enations, Royal Ann leaves develop dense tomentose areas between twisted distorted veins. Unlike other strains of TomRSV, trunks may develop only scattered pockets of shallow pits in the vascular cambium area.
- Remove diseased trees.
- Pre-plant soil fumigation to manage dagger nematode vectors.
- Plant certified, virus-tested (and found to be free of all known viruses) nursery stock.
References Hadidi, A., Barba, M., Candresse, T., and Jelkmann, W. 2011. Virus and Virus-like Diseases of Pome and Stone Fruits. St. Paul, MN: APS Press.
Milbrath, J.A., and Reynolds, J.E., 1961. Tomato ringspot virus isolated from Eola rasp leaf of cherry in Oregon. Plant Disease Reptr. 45:520-521.
Ogawa, J.M., and English, H. 1991. Diseases of Temperate Zone Tree Fruit and Nut Crops. University of California.