Link to home

Distribution and titer of Little cherry virus 2 (LChV2) in Prunus avium in time and space.

Alice Wright: Washington State University

<div><em>Little cherry virus 2</em> (LChV2) is one of the causative agents of little cherry disease, which produces misshapen, unpalatable fruit in infected cherry (<em>Prunus avium</em>) trees, resulting in yield losses for growers. Since its emergence in 2010, this disease has been spreading rapidly in cherry orchards across the Pacific Northwest. A major issue hindering control of this disease is early detection and diagnosis, as the virus is not evenly distributed within a host and titer fluctuates seasonally. In this study, we aim to follow the titer and distribution of LChV2 in different tissues of a single plant across two years. To do so, RNA is being extracted from multiple tissues throughout the year of a 10-year-old <em>P. avium</em> cv. Lambert tree infected with the LC-5 isolate of LChV2. In late summer, titer was greatest in the midrib, being 1.5 to 5.6 times greater than the petiole, 510 times greater than the wood scrapings, and 10,000 times greater than the buds. In mid-fall the results were more variable. Titer in the midrib was 0.9 to 3.1 times greater than the petiole, 0.9 to 4.8 times greater than the wood scrapings, 4.7 to 99 times greater than the roots, and 18 to 38 times greater than the buds. Data collection will continue throughout the year to assess how titer and distribution vary seasonally. Knowing the distribution and titer of LChV2 will allow for better sampling of <em>P. avium </em>for LChV2 detection and reduce the occurrence of false negatives.</div>