Emergence of Southern Rice Black-Streaked Dwarf Virus in the Centuries-Old Chinese Yuanyang Agrosystem of Rice Landraces

Pascal Alonso (1) , Pierre Gladieux (1) , Oumaima Moubset (1) , Pei-Jung Shih (1, 2) , Pierre Mournet (3) , Julien Frouin (3) , Laurence Blondin (1) , Romain Ferdinand (1) , Emmanuel Fernandez (1) , Charlotte Julian (1) , Denis Filloux (1) , Henri Adreit (1) , Elisabeth Fournier (1) , Aurélie Ducasse (1) , Vladimir Grosbois (4) , Jean-Benoit J.-B. Morel (1) , Huichuan Huang (5) , Baihui Jin (5) , Xiahong He (5, 6) , Darren P. Martin (7) , Christian Vernière (1) , Philippe Roumagnac (1)

1 UMR BGPI - Biologie et Génétique des Interactions Plante-Parasite
2 National Chung Hsing University
3 UMR AGAP - Amélioration génétique et adaptation des plantes méditerranéennes et tropicales
4 UMR ASTRE - Animal, Santé, Territoires, Risques et Ecosystèmes
5 State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan
6 SWFU - Southwest Forestry University
7 Computational Biology Group, Institute of Infectious Diseases and Molecular Medicine

Southern rice black-streaked dwarf virus (SRBSDV), which causes severe disease symptoms in rice (Oriza sativa L.) has been emerging in the last decade throughout northern Vietnam, southern Japan and southern, central and eastern China. Here we attempt to quantify the prevalence of SRBSDV in the Honghe Hani rice terraces system (HHRTS)-a Chinese 1300-year-old traditional rice production system. We first confirm that genetically diverse rice varieties are still being cultivated in the HHRTS and categorize these varieties into three main genetic clusters, including the modern hybrid varieties group (MH), the Hongyang improved modern variety group (HY) and the traditional indica landraces group (TIL). We also show over a 2-year period that SRBSDV remains prevalent in the HHRTS (20.1% prevalence) and that both the TIL (17.9% prevalence) and the MH varieties (5.1% prevalence) were less affected by SRBSDV than were the HY varieties (30.2% prevalence). Collectively we suggest that SRBSDV isolates are freely moving within the HHRTS and that TIL, HY and MH rice genetic clusters are not being preferentially infected by particular SRBSDV lineages. Given that SRBSDV can cause 30-50% rice yield losses, our study emphasizes both the need to better monitor the disease in the HHRTS, and the need to start considering ways to reduce its burden on rice production.

Mots clés: Southern rice black-streaked dwarf virus; Honghe Hani rice terraces system; host genotyping; virus emergence

Mots clés: rice; virus prevalence

Domaines: Sciences agricoles

Pascal Alonso, Pierre Gladieux, Oumaima Moubset, Pei-Jung Shih, Pierre Mournet, et al.. Emergence of Southern Rice Black-Streaked Dwarf Virus in the Centuries-Old Chinese Yuanyang Agrosystem of Rice Landraces. Viruses, 2019, 11 (11), pp.1-13. ⟨10.3390/v11110985⟩. ⟨hal-02619099⟩