Traoré Oumar, Pinel Agnès, Hébrard Eugénie, Dieudonné Gumedzoé Mawena Y, Fargette Denis, Traoré Alfred S, Konaté Gnissa
Institut de l' Environnement et de Recherches Agricoles (INERA) 01 BP 476 Ouagadougou 01, Burkina Faso.
Institut de Recherche pour le Développement, IRD, 64501, 34394 Montpellier cedex 5, France.
Plant Dis. 2006 Mar;90(3):259-263. doi: 10.1094/PD-90-0259.
Rice yellow mottle virus (RYMV) is the most important rice-infecting virus in Africa. Highly resistant rice (Oryza spp.) cultivars Gigante and Tog5681 were challenged with virus isolates from five countries of the west and central African Sudano-savannah zone in order to investigate the occurrence and prevalence of resistance-breaking (RB) isolates. High resistance was overcome by 38.6% of the isolates. RB isolates could be divided into three main pathogenic groups. Isolates of the first group (17.5%) and of the second group (16.4%) were able to break down the resistance of Gigante only and of Tog5681 only, respectively. Resistance in both cultivars was overcome simultaneously by isolates of the third group (4.7%). In each group, some isolates induced symptoms, whereas plant infection by others was evidenced only by serological tests. RB isolates occurred in all five countries with varying frequencies (19 to 57%). The wide geographical distribution and high frequencies of RB isolates represent a high risk for the durability of resistance to RYMV in the Sudano-savannah zone.
水稻黄斑驳病毒（RYMV）是非洲最重要的感染水稻的病毒。为了调查抗性突破（RB）分离株的发生情况和流行程度，用来自西非和中非苏丹 - 萨赫勒地区五个国家的病毒分离株对高抗水稻品种Gigante和Tog5681进行了挑战。38.6%的分离株克服了高抗性。RB分离株可分为三个主要致病组。第一组（17.5%）和第二组（16.4%）的分离株分别只能突破Gigante和Tog5681的抗性。第三组（4.7%）的分离株同时克服了两个品种的抗性。在每组中，一些分离株会引发症状，而其他一些分离株仅通过血清学检测证明植物受到感染。RB分离株在所有五个国家均有出现，频率各不相同（19%至57%）。RB分离株的广泛地理分布和高频率对苏丹 - 萨赫勒地区对RYMV抗性的持久性构成了高风险。
