C.N.R. - Institute of Agro-environmental and Forest Biology, Viale Marconi 2, 05010 Porano, Terni, Italy.
J Biotechnol. 2012 Jun 30;159(4):251-64. doi: 10.1016/j.jbiotec.2011.08.020. Epub 2011 Aug 22.
Juglans nigra and Juglans regia are two highly economically important species for wood and fruit production that are susceptible to anthracnose caused by Gnomonia leptostyla. The identification of genotypes resistant to anthracnose could represent a valid alternative to agronomic and chemical management. In this study, we analyzed 72 walnut genotypes that showed a variety of resistance phenotypes in response to natural infection. According to the disease severity rating and microsatellite fingerprinting analysis, these genotypes were divided into three main groups: (40) J. nigra resistant, (1) J. nigra susceptible, and (31) J. regia susceptible. Data on leaf emergence rates and analysis of in vivo pathogenicity indicated that the incidence of anthracnose disease in the field might be partially conditioned by two key factors: the age and/or availability of susceptible leaves during the primary infection of fungus (avoidance by late flushing) and partial host resistance. NBS profiling approach, based on PCR amplification with an adapter primer for an adapter matching a restriction enzyme site and a degenerate primer targeting the conserved motifs present in the NBS domain of NBS-LRR genes, was applied. The results revealed the presence of a candidate marker that correlated to a reduction in anthracnose incidence in 72 walnut genotypes.
黑胡桃和欧洲胡桃是两种具有重要经济价值的树种，可用于木材和果实生产，但它们容易受到由围小丛壳菌引起的炭疽病的侵害。鉴定对炭疽病具有抗性的基因型可能是农业和化学管理的有效替代方法。在这项研究中，我们分析了 72 个胡桃基因型，这些基因型对自然感染表现出多种不同的抗性表型。根据疾病严重程度评分和微卫星指纹分析，这些基因型分为三个主要组：（40）黑胡桃抗性、（1）黑胡桃易感性和（31）欧洲胡桃易感性。叶片萌发率数据和体内致病性分析表明，田间炭疽病的发病率可能部分取决于两个关键因素：真菌初次感染时易感叶片的年龄和/或可用性（通过晚发避免）和部分宿主抗性。基于与接头引物匹配的限制酶位点的接头引物和针对 NBS-LRR 基因 NBS 结构域中保守基序的简并引物进行 PCR 扩增的 NBS 谱分析方法被应用。结果显示，候选标记的存在与 72 个胡桃基因型炭疽病发病率的降低相关。
