Identification of an Emaravirus in a Common Oak (Quercus robur L.) Conservation Seed Orchard in Germany: Implications for Oak Health
Open Access
- 4 November 2020
- Vol. 11 (11), 1174
- https://doi.org/10.3390/f11111174
Abstract
We observed the health status of oak trees in a conservation seed orchard for over twenty years, focusing on characteristic virus-suspected symptoms. The orchard was established in 1992 in Kreuztal, North Rhine-Westphalia (Germany) with 1302 seedlings in 186 clusters. The number of seedlings showing chlorotic ringspots and mottle on leaves has fluctuated annually, but has increased from 3.3% to 12.1% in the last 20 years; the number of affected clusters has risen from 8% to 25.9%. A scientific breakthrough was the identification of a novel virus related to members of the genus Emaravirus in diseased oak by high-throughput sequencing (HTS). Screening of the oak seedlings in three consecutive years, using a newly established virus-specific diagnostic reverse transcription polymerase chain reaction (RT-PCR), confirmed the virus infection and revealed a close to 100% association between the observed leaf symptoms and the novel virus. As no other plant virus could be identified in the HTS-datasets, we assume the novel virus is primarily causing the symptoms. To reliably detect the novel virus in oaks, RT-PCR targeting the viral RNA3 or RNA4 should be applied in routine testing of symptomatic leaf tissue. It was obvious that most groups with virus-infected plants cluster, with only five out of the 42 affected groups being offside, not bordering on other affected groups of plants. There was no clear correlation between the detection of the virus and the overall vitality of the seedlings. There was no relation between seedling performance and presence or absence of viral infection. Forecasts on the future growth behavior of these virus-infected oak trees are therefore not possible.Keywords
This publication has 38 references indexed in Scilit:
- Disease Interactions in a Shared Host Plant: Effects of Pre-Existing Viral Infection on Cucurbit Plant Defense Responses and Resistance to Bacterial Wilt DiseasePLOS ONE, 2013
- A life history view of mutualistic viral symbioses: quantity or quality for cooperation?Current Opinion in Microbiology, 2013
- Growth and quality of young oaks (Quercus robur and Quercus petraea) grown in cluster plantings in central Europe: A weighted meta-analysisForest Ecology and Management, 2012
- Virus infection decreases the attractiveness of white clover plants for a non-vectoring herbivoreOecologia, 2012
- Impact of Erysiphe alphitoides on transpiration and photosynthesis in Quercus robur leavesEuropean Journal of Plant Pathology, 2009
- Forest management and silvicultural responses to projected climate change impacts on European broadleaved trees and forestsInternational Forestry Review, 2008
- MEGAN analysis of metagenomic dataGenome Research, 2007
- Mounding site preparation for forest restoration: Survival and short term growth response in Quercus robur L. seedlingsForest Ecology and Management, 2006
- Studies on virus infection of diseased Quercus robur (L) from forest stands in northern GermanyAnnals of Forest Science, 1996
- Infectious diseases in forest trees caused by viruses, mycoplasma-like organisms and primitive bacteriaCellular and Molecular Life Sciences, 1985