Boso Susana, Gago Pilar, Santiago José-Luis, de la Fuente María, Martínez María-Carmen
The Biological Mission of Galicia (CSIC), Carballeira 8, Pontevedra 36080, Spain.
Plant Pathol J. 2019 Apr;35(2):125-136. doi: 10.5423/PPJ.OA.09.2018.0194. Epub 2019 Apr 1.
is very susceptible to downy mildew () A number of authors have suggested different genetic populations of this fungus exist in Europe, each showing a different degree of virulence. Work performed to date indicates this diversity to be the result of different factors. In areas where gene flow is greater and recombination more frequent, the diversity of appears to be wider. In vineyards isolated by geographic barriers, a race may become dominant and produce clonal epidemics driven by asexual reproduction. The aim of the present work was to identify the conditions that influence the genetic diversity of populations in the vineyards of northwestern Spain, where the climatic conditions for the growth of this fungus are very good. Vineyards situated in a closed, narrow valley of the interior, in more open valleys, and on the coast were sampled and the populations of detected were differentiated at the molecular level through the examination of microsatellite markers. The populations of represented in primary and secondary infections were investigated in the same way. The concentration of airborne sporangia in the vegetative cycle was also examined, as was the virulence of the different populations detected. The epidemiological characteristics of the fungus differed depending on the degree of isolation of the vineyard, the airborne spore concentration, and on whether the attack was primary or secondary. Strong isolation was associated with the appearance of dominant fungal races and, therefore, reduced populational diversity.
对霜霉病非常敏感。一些作者认为，这种真菌在欧洲存在不同的遗传群体，每个群体表现出不同程度的毒力。迄今为止开展的研究表明，这种多样性是由不同因素造成的。在基因流动较大且重组更频繁的地区，该真菌的多样性似乎更广泛。在被地理屏障隔离的葡萄园里，一个小种可能会占据主导地位，并通过无性繁殖引发克隆性流行。本研究的目的是确定影响西班牙西北部葡萄园里该真菌群体遗传多样性的条件，该地区的气候条件非常有利于这种真菌的生长。对位于内陆封闭狭窄山谷、更开阔山谷以及沿海地区的葡萄园进行了采样，并通过检测微卫星标记在分子水平上区分所检测到的该真菌群体。以同样的方式研究了初次感染和二次感染中该真菌的群体情况。还检测了营养生长周期中空气中孢子囊的浓度以及所检测到的不同该真菌群体的毒力。该真菌的流行病学特征因葡萄园的隔离程度、空气中孢子浓度以及感染是初次还是二次而有所不同。高度隔离与优势真菌小种的出现相关，因此群体多样性降低。
